Posted: April 24th, 2025

i need a rough draft.

Final paper grading rubric is used as a guide for improving your draft 1.  Not all categories of the rubric will be used for this draft.  The grade shown will not be included in the calculation of your lab grade and is used as a guide.  Your final grade for these sections could be higher or lower based on your review and corrections.  Review the Paper section of the lab syllabus.

Practice upload two days before closing of the assignment will add two points to the final paper grade.

Rubric

Lab Final Paper 23Lab Final Paper 23CriteriaRatingsPtsThis criterion is linked to a Learning OutcomeTitle PageFormatted correctly with all required contents.3 to >2.0 ptsProficient2 to >0.0 ptsNeeds ImprovementNeeds careful review of required contents. Some contents missing or formatting issues0 ptsUnsatisfactoryTitle page missing3 pts
This criterion is linked to a Learning OutcomeTitleConcisely explains major theme of the project. Title is original.3 to >2.0 ptsProficient2 to >0.0 ptsNeeds ImprovementNeeds careful review of category statement. Some contents missing or needs improvement of how it is stated.0 ptsUnsatisfactoryTitle missing3 pts
This criterion is linked to a Learning OutcomeAbstractOne paragraph. No more than 250 words.
Concisely states the objectives, methods, results and conclusions.10 to >7.0 ptsProficient7 to >0.0 ptsNeeds improvementNeeds careful review of category statement. Some contents missing or needs improvement of how it is stated.0 ptsUnsatisfactoryAbstract missing10 pts
This criterion is linked to a Learning OutcomeIntroductionThree paragraphs.

1. General background information about the topic that links to the specific objective(s) of the experiment. Citations in APA format.

2. Specific information about the enzyme tested.
Accurately presents the specific objective(s) of the experiment. Provides a very brief summary of the methods(s) used. Citations in APA format.

3. States null and alternative hypotheses. States a specific prediction for each plant tested.15 to >13.0 ptsProficient13 to >0.0 ptsNeeds ImprovementNeeds careful review of category statement. Some contents missing or needs improvement of how it is stated.0 ptsUnsatisfactoryIntroduction missing15 pts
This criterion is linked to a Learning OutcomeMaterials and MethodsGives enough details to allow for replication of each required protocol. Clearly states the positive control and experimental groups for each plant tested. Clearly states results of standardization experiments and any adjustments to mixing tables.

Links the four parts of the experiment so that the reader can see the purpose of each.

Correct use of citations in APA format.

Effectively organizes this section with subheadings for each protocol.15 to >13.0 ptsProficient13 to >0.0 ptsNeeds ImprovementNeeds careful review of category statement. Some contents missing or needs improvement of how it is stated.0 ptsUnsatisfactoryMaterials and Methods missing15 pts
This criterion is linked to a Learning OutcomeResultsAll required graphs are presented.
Microsoft Excel is used to create graphs
Each graph opens with a quantitative summary of major trends.
Each graph has all required components.
Graphs are presented in the same order as the protocols in the Materials and Methods section.
Appendix section placed after Literature Cited section
All tables of raw data are presented in the same order as the graphs and have all required components.25 to >20.0 ptsProficient20 to >0.0 ptsNeeds ImprovementNeeds careful review of category statement. Some contents missing or needs improvement of how it is stated or presented.0 ptsUnsatisfactoryResults and Appendix sections missing25 pts
This criterion is linked to a Learning OutcomeDiscussionTwo paragraphs

Interprets results. Supports conclusions using quantitative results as evidence. Relates quantitative results to structural changes to peroxidase. Citations in APA format.

Compares results to hypotheses stated in the Introduction. States whether hypotheses were accepted or rejected and why. Compares results to findings of other scientists (primary sources).15 to >13.0 ptsProficient13 to >0.0 ptsNeeds ImprovementNeeds careful review of category statement. Some contents missing or needs improvement of how it is stated.0 ptsUnsatisfactoryDiscussion missing15 pts
This criterion is linked to a Learning OutcomeLiterature CitedCitations follow APA format and are cited in the body of the paper. Required number of primary and tertiary sources.4 to >2.0 ptsProficient2 to >0.0 ptsNeeds ImprovementNeeds careful review of category statement. Some sources missing . Formatting issues.0 ptsUnsatisfactoryNo citations provided4 pts
This criterion is linked to a Learning OutcomeGeneralPaper is written in scientific style, direct and to the point. Chemical formulas accurate and formatted correctly.
Spelling and grammar are correct.
Sentence structure is accurate.
Correct use of active and passive voice.10 to >7.0 ptsProficient7 to >0.0 ptsNeeds ImprovementNeeds careful review of category statement. Some contents missing or needs improvement of how it is stated.0 ptsUnsatisfactoryNo paper submitted10 pts
Total Points: 100

Scientific African

10

(2020) e00608

Contents lists available at ScienceDirect

Scientific African

journal homepage: www.elsevier.com/locate/sciaf

Peroxidase from waste cabbage ( Brassica oleracea capitata L .)

exhibits the potential to biodegrade phenol and synthetic

dyes from wastewater

Enoch B. Joel a , ∗, Simon G. Mafulul a , Hadiza E. Adamu

a , Lazarus J. Goje

b ,
Habibu Tijjani c , Adedoyin Igunnu

d , Sylvia O. Malomo

d

a Department of Biochemistry, Faculty of Basic Medical Sciences, College of Health Sciences, University of Jos, Jos, Nigeria
b Department of Biochemistry, Faculty Science, Gombe State University, Gombe, Nigeria
c Department of Biochemistry, Bauchi State University, Gadau, Nigeria
d Department of Biochemistry, Faculty of Life Sciences, University of Ilorin, Ilorin, Nigeria

a r t i c l e i n f o

Article history:

Received 28 July 2020

Revised 1 October 2020

Accepted 2

3

October 2020

Keywords:

Waste cabbage

Brassica oleracea

Peroxidase

Biodegradation

Phenol

Azo dyes

a b s t r a c t

Peroxidases are well known for their ability to biodegrade some recalcitrant organic pollu-

tants like phenol and their derivatives resulting in a reduction in their toxicity. The present

study was designed to extract, characterize, and evaluate the potential of partially purified

peroxidase from discarded and decaying waste cabbage leaves in the biodegradation of

phenol and some common synthetic azo dyes. This was done by first partially purifying the

crude extract of waste cabbage peroxidase (WCP) using ammonium sulfate precipitation,

dialysis, and gel filtration chromatography. Thereafter, the experimental determination of

protein concentration, peroxidase activity, and biodegradation of phenol and azo dyes was

done spectrophotometrically. The results showed a purification fold of 87.6

5

with a 34.92%

yield. The partially purified peroxidase had its optimum activity at temperature 30 °C, pH

5.5 while showing broad substrate preference with ABTS been the substrate. The stability

studies also showed that WCP was stable over a wide range of pH (4.0–7.0) and 41% of

its original activity was retained at 80 °C indicating that it is a thermostable enzyme. The

kinetic data

of WCP showed K m

values of 1.24, 17.89, and 19.2

4

mM and V max values of

1111.11, 909.09, and 588.24 mM /minutes for ABTS, guaiacol, and o-dianisidine

respectively.

Three metal ions, Hg

2

+ , Cu 2 + , Ni 2 + , organic solvent (acetone), EDTA, and urea inhibited

peroxidase activity; whereas Mn 2 + and Zn 2 + showed slight activation. The partially puri-

fied WCP exhibited high efficiency for the biodegradation of synthetic azo dyes and phenol

at the lab-scale. After 48 h incubation, the waste cabbage peroxidase efficiently catalyzed

the decolorization of tested azo dyes at varying degrees; azo blue 5, azo purple, azo yellow

6, and citrus red 2, with a percentage decolorization of 85.1, 69.1, 46.2 and 42.9%, respec-

tively. The waste cabbage peroxidase also shows up to 91.1% efficiency for degradation of

phenol in aqueous solution after 60 min. Findings from this study provide promising evi-

dence on the possibility of utilizing/recycling a readily abundant waste cabbage to useful

bioproducts like peroxidase enzyme with the ability to biodegrade azo dyes and phenol at

a small scale in the laboratory. Moreover, the findings from this study increase the prospect

of waste cabbage peroxidase for the treatment of industrial effluents containing dyes and

∗ Corresponding author.

E-mail address: banbilbwaj@unijos.edu.ng (E.B. Joel).

https://doi.org/10.1016/j.sciaf.2020.e00608

2468-2276/© 2020 The Authors. Published by Elsevier B.V. on behalf of African Institute of Mathematical Sciences / Next Einstein Initiative. This is an

open access article under the CC BY license ( http://creativecommons.org/licenses/by/4.0/ )

https://doi.org/10.1016/j.sciaf.2020.e00608

http://www.ScienceDirect.com

http://www.elsevier.com/locate/sciaf

http://crossmark.crossref.org/dialog/?doi=10.1016/j.sciaf.2020.e00608&domain=pdf

mailto:banbilbwaj@unijos.edu.ng

https://doi.org/10.1016/j.sciaf.2020.e00608

http://creativecommons.org/licenses/by/4.0/

Jaylin Wares

E.B. Joel, S.G. Mafulul, H.E. Adamu et al. Scientific African 10 (2020) e00608

phenolic pollutants. The approach of transforming waste from one source into a useful bio-

catalyst that can potentially be exploited to treat waste pollutants from a different source

offers a chain of green technology.

© 2020 The Authors. Published by Elsevier B.V. on behalf of African Institute of

Mathematical Sciences / Next Einstein Initiative.

This is an open access article under the CC BY license

( http://creativecommons.org/licenses/by/4.0/ )

Introduction

One of the major environmental challenges, facing the world today is pollution, which is the contamination of soil, wa-

ter, and air by toxic chemicals [1–4] Phenol and azo dyes are hazardous pollutants released from industrial effluents such as

textile, leather, food, and cosmetic, petroleum/petrochemical pose a threat to the environmental safety [5] . In Nigeria, azo

dye residues, phenol, and other phenolic derivatives arising anthropogenic practices such as industrial activities, petroleum

and petroleum derivatives (such as gasoline, diesel, and kerosene spills), extensive use of pesticides/herbicides in modern

agriculture, and extensive use of synthetic azo dyes as a colorant in the food and textile industries constitute an impor-

tant environmental concern to human health [3 , 6] . Due to the poor wastewater treatment system in Nigeria, this effluent

containing harmful organic pollutants are usually discharged untreated or partially treated in the mainstream of water re-

sources or land sites [7–10] . And even at low concentrations, the azo dye residues and phenolic pollutants can persist in the

environment for long which becomes noxious to terrestrial and aquatic life and in turn, affects human health [2 , 11] . There-

fore, the treatment of industrial effluents containing reactive azo dyes and other phenolic pollutants has become necessary

before they can be discharged into the ecosystem [11] . Numerous other physicochemical methodologies have been utilized

in the post-treatment of azo dyes and other phenolic derivatives from industrial effluents, which include coagulation, ad-

sorption, degradation by ozonation reaction, precipitation, chemical degradation, and irradiation [2 , 12] . However, existing

physicochemical methods are usually expensive and commercially unattractive, time-consuming procedures, not capable of

treating a variety of pollutants, and sometimes generate some byproducts that are more harmful than the parent pollutant

thus creating disposal problems [2 , 13–15] . Biological treatment methods of waste pollutants such as microbial and enzyme-

mediated biodegradation provide a cost-effective, eco-friendly alternative to existing physicochemical technologies applied

to treat different kinds of azo dye residues and phenolic pollutants [

14

, 15] .

The ability of the microorganism to degrade different azo dyes, phenol, and other aromatic pollutants has been widely at-

tributed to their unique ability to secrete and utilize intracellular oxidoreductive enzymes such as peroxidases [

6

, 10] . Hence,

the direct use of extracted peroxidase for biodegradation of poisonous organic pollutants may be a better option because

enzymes are easy to work with and can degrade a wide range of pollutants generating non-toxic products [

9

, 16] . Oxidore-

ductive enzymes especially peroxidases Peroxidases are unique biocatalyst with the potential ability to react with a broad

range of organic environmental pollutants (such as azo dyes and phenolic compounds) in the presence of H 2 O 2 , thereby

remove them by precipitation or the cleavage of the aromatic ring structure, transforming them into other nontoxic byprod-

ucts [17–20] . Peroxidases (E.C. 1.11.1.7) are ubiquitous enzymes widely distributed in plants, animals, and micro-organisms

[21 , 22] . They are heme-containing enzymes that utilize hydrogen peroxide as an oxidant to catalyze the oxidation reaction of

broad electron donor substrates (e.g. phenols, aromatic amines, indoles, and sulfonates) [23–25] . Peroxidases have attracted

industrial attention due to its multiple applications which include bioremediation of wastewater such as decolorization of

dyes as effluents of textile industries [26] , and removal of carcinogenic phenolic pollutants from industrial effluents [2

7

, 28] .

Peroxidases are also applicable in clinical diagnosis and laboratory experiments such as enzyme-linked immunoassay (ELISA)

kits [29 , 30] , preparation of biosensor [31 , 32] treatment of cancer [33] , synthesis of aromatic chemicals and polymeric mate-

rials, and removal of peroxides from foodstuffs in food industries [30 , 34 , 35] .

Peroxidases have been identified as one of the suitable enzymes for the treatment of phenolic contaminants and related

compounds [36] . However, most of the studies carried out using purified HRP usually imposed a high cost [36] . This has

necessitated the search for alternative peroxidases from other cheap and local sources with the capability for biodegradation

of phenolic pollutants from traditional and industrial effluents in developing countries like Nigeria. Although several other

works on the use of peroxidases in this regard have been reported and several attempts have been made to search for local

sources of peroxidases as an alternative to the commercially available peroxidases like horseradish peroxidase [25] , artichoke

peroxidase [37] , and Schizophyllum fungal peroxidase [38] . Given this peroxidase activity has been investigated in a range of

vegetables and fruits such as water Spinach [39] , Broccoli [40] , moringa leaves [41] , oranges [42] , papaya [43] , and cabbage

[44 , 45] . However, the current global system aimed at minimizing competition with fresh foodstuffs like vegetables and fruits

due to growing malnutrition and food insecurity. Hence, rather than resorting to fresh vegetables and fruits for isolation of

peroxidase, exploring waste vegetables and fruits as a source of peroxidase would be a better op

tion.

Cabbage ( Brassica oleracea var. capitata ) is a well-known vegetable that has been widely studied for nutritional value and

bioactive substances [46] . It is one of the major vegetable food crops cultivated on the Jos plateau, Nigeria because of the

near temperate climate. It is extensively consumed in this area and across the globe as a food [47 , 48] . It is usually grown

2

http://creativecommons.org/licenses/by/4.0/

Jaylin Wares

Jaylin Wares

E.B. Joel, S.G. Mafulul, H.E. Adamu et al. Scientific African 10 (2020) e00608

and harvested in large quantities to supply other parts of the country. Most often the supply for perishable vegetables like

cabbage usually exceeds its demand, which leads to large amounts being rotten and wasted due to poor storage systems.

Furthermore, over 60 percent of the global total food losses and wastages are from fruits and vegetables and this is common

in developing countries like Nigeria due to poor market chain and storage facilities [49] . Due to poor waste management

strategies, the vegetable and fruit wastes are incriminated for a high quantity of pollution and constitute a source of envi-

ronmental nuisance in the municipal of developing countries like Nigeria [50] . Though Government policies are being put in

place for adequate storage facilities to prevent these spoilages and wastages but yet to be fully implemented. Hence, consid-

ering other possible ways for the utilization of these wastes for the production of valuable products like peroxidase enzyme

has become necessary. Peroxidase from fresh cabbage leaves has been characterized and tested for decolorization some syn-

thetic dyes [44 , 45 , 51] in an attempt to search for a cost-effective alternative to the commercially available peroxidases such

as horseradish peroxidase [25] , artichoke peroxidase [37] , and Schizophyllum fungal peroxidase [38] . Even though, isolation

of peroxidase from cabbage and their application for decolorization dyes are known. However, fresh cabbage may not be a

viable source because all effort s have to be made to minimize competition with food consumption.

It has been reported many fruit and vegetable wastes contain several exogenous enzymes many other re-usable products

of high value with different industrial applications, with adequate technology, such agro-waste residual matter can be con-

verted into cost-effective commercial products [52 , 53] . And in Nigeria cabbage and other vegetables usually rot/decay and

become waste in the market due to lack of storage facilities. Therefore, exploring the utilizing of such agro-waste residual

matter as a potential source for extraction re-usable substances of high value (particularly enzymes like peroxidases) could

be a more cost-effective source for value-added peroxidase enzymes and would have the potential for industrial application

such as wastewater treatment. Considering the waste cabbage as a source of peroxidase could be more viable because it

is not in competition with food consumption and is a way of recycling agro-waste pollution that constitutes a municipal

environmental nuisance. This study attempts to explore the discarded decaying waste cabbage as a better alternative to

fresh cabbage as a potential cost-effective source of peroxidase. Therefore; this work was design to isolate, characterized

the biochemical properties of waste cabbage peroxidase, and testes its potential ability to biodegrade azo dyes and phenol

from aqueous solution. This kind of study will provide evidence for exploration of agro-based waste as a source of useful

products like peroxidase enzyme that can be applied for actual and large-scale treatment of industrial effluents containing

azo dyes and phenolic pollutants. This approach offers a chain of green technology since waste from one source is being

transformed into a useful biocatalyst for waste treatment from another source [36] .

Materials and methods

Materials and reagents

The decaying waste cabbage ( Brassica oleracea var. capitata ) was collected from Farin Gada vegetable Market, Jos, Plateau

State, Nigeria. Ammonium sulfate, Ciocalteu reagent, bovine serum albumin, ethylene diamine tetraacetic acid (EDTA), ace-

tone, urea, substrates O-dianisidine, guaiacol and 2, 2 ′ -Azino-bis (3-Ethylbenzthiazoline-6-Sulfonic Acid) [ABTS], Sephadex

G-75, azo citrus red 2, azo purple, azo yellow 6, and azo blue 5, and phenol were procured from Sigma Aldrich. All these

and other chemicals used in this study were of analytical grade and obtained from commercial sources.

Extraction of waste cabbage peroxidase

Extraction of crude peroxidase from waste cabbage

Peroxidase was extracted from waste cabbage leaves using the method of [54] with slight modifications. Waste cabbage

leaves were weight (50 g) and homogenized with 200 ml of 0.1 M Tris-HCl buffer, pH 7.5 for 10 min. The homogenate was

filtered with a clean cheesecloth arranged in two layers and the filtrate was subjected to centrifugation using a refrigerated

centrifuge (4 °C) at 10,0 0 0 rpm for

15

min. The supernatant was carefully collected and filtered into a clean tube through

Whatman No. 1 filter paper and the clearer filtrate was used as crude homogeneous waste cabbage peroxidase (WCP).

Thermal treatment of crude extract of waste cabbage peroxidase

The extracted crude waste cabbage peroxidase was incubated at 65 °C for 5 min using a water bath and cooled on ice

for 25 min to selectively inactivate any contaminating traces of catalase moieties in the crude homogeneous sample.

Peroxidase assay and protein determination

The total protein concentration was determined by the Lowry method [55] using Folin’s Ciocalteu phenol reagent with

graded concentrations of bovine serum albumin (BSA) as the standard. The straight-line equation of the plot of the net

absorbance values at λ= 595 nm versus the concentrations of BSA was used to determine the protein concentration of the

unknown sample(s).

Peroxidase activity was assayed via time course spectrophotometric, rate determination using ABTS as substrate according

to the method of [56] with minor modifications. An aliquot of 2.7 ml of 0.1 M Tris-HCl buffer solution (pH 7.5) 100 μl

of crude enzyme extract and 100 μl of a substrate (3.0 mM ABTS) were pipetted into clean cuvettes. The reaction was

3

Jaylin Wares

Jaylin Wares

E.B. Joel, S.G. Mafulul, H.E. Adamu et al. Scientific African 10 (2020) e00608

initiated by the addition of 100 μl 3% of hydrogen peroxide and the increase in the absorbance was monitored using UV–VIS

spectrophotometer (model-CHEBIOS s.r.l., Rome, Italy), as the amount of ABTS •+ radical produced at the 20-second interval

for 3 min (as a function of peroxidase activity) at 3

16

nm ( Ɛ416 nm = 36 mM

−1 cm

−1 ). The absorbance values shown were

zeroed with those obtained in reactions that did not include the partially purified WCP.

The corresponding change in absorbance values was used to calculate peroxidase activities ( Table 1 legend for conver-

sions formula). Peroxidase activity is, therefore, defined as the amount of ABTS substrate converted to ABTS •+ radical (prod-

uct) per minute.

Partial purification of crude peroxidase from waste cabbage

Ammonium sulfate precipitation of crude waste cabbage peroxidase and dialysis

The principle of ammonium sulfate precipitation is that at higher salt concentrations, protein solubility usually decreases,

leading to precipitation which is termed salting-out. Graded concentrations of ammonium sulfate salt that correspond to 40-

90% was added to the crude WCP and subjected to stirring for complete precipitation and allowed to stay for about 4 h in

the fridge. The resulting precipitate was collected by centrifugation at 40 0 0 rpm for 15 min at 4 °C and pellets were re-

dissolved in a small amount of extraction buffer- 0.1 M Tris-HCl buffer solution (pH 7.5). Each of the individual percentage

saturation was then analyzed successively and the concentration with the highest activity was subjected to further purifica-

tion.

Dialysis through a semi-permeable membrane dialysis tubule is usually carried out after salting out to separate the

protein enzyme from salt and other small molecules. The re-suspended pellets obtained from 75% saturation was poured in

a dialysis tubule sealed securely and dialyzed against 0.1 M Tris-HCl buffer solution (pH 7.5) by constant magnetic stirring

for

12

h with 4 h interval for change of the extraction buffer. The dialyzed WCP was used for further purification.

Gel filtration chromatography

The dialyzed WCP was subjected to further purification by gel filtration chromatography using Sephadex-G-75 as a col-

umn. The glass column having an inner diameter of 1.5 cm was packed with a column of 15 cm height. The 2 ml of dialyzed

peroxidase was loaded on the column and eluted with phosphate buffer at pH 7. Fractions of purified enzyme were collected

at a flow rate of 1 ml per tube and the peroxidase activity with protein concentrations were determined as described ear-

lier in section 2.3 . The fractions with significant activities were pooled together and used as the purified WCP for a further

experiment involving biochemical characterization of WCP properties and potential application in biodegradation of phenol

and azo dyes.

Biochemical characterization of partially purified waste cabbage peroxidase properties

Determination of the effect of pH on waste cabbage peroxidase activity and stability

To determine the optimum pH of WCP, peroxidase activity was assayed for at different pH values. The Reaction mixture

contained 3% of H 2 O 2 , 0.1 M buffers of varying pH (2–9), enzyme, and 3 mM ABTS carried out for 3 min (change in ab-

sorbance measured at 20-second intervals). To achieve this, different buffers of uniform concentration (0.1 M) were prepared

and used as assay buffers and these include a glycine-HCl buffer (pH 2.0 to 5.0), phosphate buffer (pH 6 to 7), and Tris-HCl

(pH 8.0 to 10). To determine the pH stability the residual peroxidase activity was assayed after 24 hours incubation at room

temperature in a series of assay buffers with varying pH varying from 2.0 to 9.0. Thereafter peroxidase activity was assayed

as

usual ( see Section 2.3 ).

Determination of the effect of temperature on waste cabbage peroxidase activity and stability

To determine the optimum temperature of WCP, peroxidase activity was assayed at varying temperatures (10 to 90 °C) in

a reaction mixture containing 3% of H 2 O 2 , 0.1 M Phosphate buffer solution (pH 6.0), enzyme, and 3 mM ABTS carried out

for 3 min (change in absorbance measured at 20-second intervals). The temperature was regulated by using a water bath.

The thermal stability of the waste cabbage peroxidase was determined by incubating the enzyme without the substrate at

50 °C, 60 °C, 70 °C, and 80 °C for 1 hour and then cooled on ice for 5 min. After cooling peroxidase activity was assayed as

usual ( see Section 2.3 ).

Kinetic constants/substrate specificity of waste cabbage leaves peroxidase

To determine the kinetic parameters (K m

and V max ) of the WCP, peroxidase activity was assayed at varying concentrations

(1.0–10 mM) of three well-known peroxidase substrates (ABTS/guaiacol/O-dianisidine) with a suitable amount of purified

enzyme, and 0.1 M Phosphate buffer (pH 6.0). Reactions were initiated by the addition of 3% of H 2 O 2 and absorbance

at 416 nm was monitored for 3 min (at 20-second intervals) and converted to peroxidase activities ( Table 1 legend for

conversions formula). The reciprocal of peroxidase activity and substrate concentrations were plotted (Lineweaver-Burk plot)

and the kinetic parameters of the partially purified peroxidase for the three substrates were calculated from the equation of

the straight line of the Lineweaver-Burk plots as follows:

1 / V=

Y=

( KM / Vmax ) ×

M ×

(1 / [S])+

X+

(1 / Vmax )

C

( Lineweaver − Burk equation ∗)
( Equation of straight line )

4

Jaylin Wares

Jaylin Wares

Jaylin Wares

Jaylin Wares

E.B. Joel, S.G. Mafulul, H.E. Adamu et al. Scientific African 10 (2020) e00608

Where: K m

= Michaelis Menten constant for a particular substrate, V = Enzyme activity (Initial rate of reaction),

V max = Maximum velocity (maximum rate of reaction) obtained for a particular substrate concentration, pH and tempera-

ture, and [S] = concentration of substrate.

Determination of the effect of chemicals and metal ions on waste cabbage peroxidase activity

The effect of divalent metal ion, EDTA, acetone, and urea on peroxidase activity was determined by pre-incubating the

enzyme with either divalent metal ion (Mg 2 + , Fe 2 + , Zn

2 + , Co 2 + , Ni 2 + ), EDTA, acetone, or urea to a final concentration of

5 mM for 30 min at room temperature. Thereafter peroxidase activity was assayed for as usual (see Section 2.3 ). The perox-

idase activity in the absence of divalent metal ion, EDTA, acetone, and urea were taken as the control

experiments.

Application waste cabbage peroxidase in biodegradation of phenol and synthetic dyes

Waste cabbage peroxidase mediated decolorization of synthetic dyes

The four tested synthetic azo dyes were selected for this study based on the availability at the time of purchase. The

aqueous solution of each azo dye was prepared to a uniform concentration of 5 mM. To determine the maximum wavelength

for each dye, the prepared solution of each dye was scanned using a UV/Visible Spectrophotometer (200–850 nm range).

Thereafter, the initial absorbance was obtained for different dyes (azo citrus red 2, azo purple, azo yellow 6, and azo blue 5)

after the addition of buffer to each of the dye solutions.

The influence of WCP on the decolorization of azo dyes was investigated at the optimum reaction condition of the charac-

terized WCP and maximum wavelength for each dye. The reaction mixture consisted of a fixed concentration of dye, partially

purified enzyme, 100 mM phosphate buffer, pH 5.5, and 3% H 2 O 2 . The reaction mixtures were incubated at 30 °C, and the

final absorbance readings were taken at varying time intervals (30 min, 1, 24, and 48 h). The percentage of decolorization

was thus calculated as follows:

Percentage Decolorization =

A i −A f

A i

∗ 100

Where A i = initial absorbance before

decolorization.

A f = final absorbance after incubation.

Note that all reactions with partially purified WCP were carried out at optimum conditions of the enzyme obtained from

the biochemical characterization to guarantee the high efficiency of dye decolorization.

Waste cabbage peroxidase mediated biodegradation of synthetic phenol

The effectiveness of the purified WCP biodegradation/removal phenol was tested. Phenol concentrations were quantified

at the initial and final stages using the 4-aminoantipyrene (4-AAP) method. The standard curve for pure phenol samples

without any enzyme was prepared. Experiments were carried out in 75 ml beakers. Varying volumes of partially purified

waste cabbage peroxidase and a particularly fixed concentration of H 2 O 2 and phenol (10 mg/L) were added into the phos-

phate buffer (pH 6.0). The mixture was shaken vigorously and allow to stand for 60 min at room temperature. Thereafter,

4.0 ml of 0.25 M sodium bicarbonate and 0.9 ml of 20.8 mM 4-aminoantipyrene were added and shaken vigorously, then

0.9 ml of 83.4 mM potassium ferricyanide was added, mixed by shaking again and allowed to stand for 9 min. Absorbance

was measured at 510 nm using an ultraviolet-visible (UV–VIS) spectrophotometer and converted to concentration using the

calibration curve. The efficiency of phenol removal (% removal) was thus calculated as follows:

% Phenol removal = ( C initial − C final ) / C initial ∗ 100

Where C initial = initial concentration (mg/L) and C final = final phenol concentration (mg/L).

Data/Statistical analysis

All data were analyzed using Microsoft Office (Excel) and values represent the means of results from three replicate

experiments.

Results

Purification of waste cabbage peroxidase

Peroxidase from waste cabbage leaves was purified to homogeneity by ammonium sulfate salting out, dialysis, and gel

filtration chromatography. The result of ammonium sulfate precipitation showed maximum peroxidase activity at 75% pre-

cipitation. The elution profile of the waste cabbage peroxidase purification scheme is as shown in Fig. 1 . The results obtained

for the degree of purity of WCP at each purification step are summarized in Table 1 . The proteins were eluted and five major

peaks (F4, F5, F6, F7and F-8) and three minor peaks (F1, F2, and F3) which indicate the presence of more than one protein.

It was found that only three major peak fractions in the same region contain peroxidase activity and the three active peaks

were pooled and used as purified WCP for biochemical characterization WCP and its effectiveness in the biodegradation of

5

Jaylin Wares

Jaylin Wares

E.B. Joel, S.G. Mafulul, H.E. Adamu et al. Scientific African 10 (2020) e00608

Fig. 1. Gel filtration chromatographic elution profile of waste cabbage peroxidase purification on the Sephadex G-75 column. The dialyzed fraction was

loaded on the Sephadex G-75 column pre-equilibrated with elution buffer 100 mM Tris-HCl buffer, pH 7.5. The protein elution profile was monitored at

280 nm.

Table 1

Summary of purification steps the degree of purity recorded for waste cabbage peroxidase.

Purification step Total enzyme Activity (U) Total Protein (mg) Specific activity (Umg −1 ) Recovery (%) Purification fold

Crude extraction 764.66 438.34 1.74 100.00 1.00

(NH 4 ) 2 SO 4 Precipitation 432.00 63.81 6.77 56.50 3.88

Dialysis 329.00 9.76 33.71 43.03 19.32

Gel filtration (Sephadex G-75) 267.00 1.75 152.89 34.92 87.65

phenol and azo dyes. This study recorded 87.62 with a high 34.92% as purification fold and purification yield respectively

for the purified waste cabbage peroxidase.

The above parameters were calculated as follows;

Peroxidase Activity ( U / ml ) =

�A / min × V × Df

36 × v × d

Where; �A/min. = Change in absorbance per minute, V = Total reaction volume (3 ml), Df = dilution factor, v = Volume

of enzyme source (0.1 ml), d = Lightpath (1 cm), 36 mM

−1 .cm

−1 = is micromolar extinction coefficient of ABTS at 416 nm.

Specific activity (U/mg): measure of enzyme’s purity = Enzyme activity (U/ml) /Total protein (mg/ml)

The percentage yield of a step = Total units of purified enzymes/Total units of crude enzymes

Purification fold (Measure of how effective the step is.) = specific activity purified enzyme/ specific activity crude en-

zymes.

Biochemical characterization of partially purified waste cabbage peroxidase

Effect of pH on activity and stability of waste cabbage peroxidase

The results of pH on peroxidase activity showed that the partially purified waste cabbage peroxidase exhibited high

activity between pH 3.5–6.5 reaching optimal at around pH 5.5 ( Fig. 2 ). To determine the pH stability of WCP, the residual

activity was carried out with ABTS as substrate, after 24 h incubation at room temperature in a series of buffers of varying

pH values ranging from pH 2.0 to 9.0. The result of the pH stability experiment suggests that the partially purified peroxide

was stable over a broad range of pH (4.0 −7.0) ( Fig. 2 ).

Effect of varying temperature on the activity of waste cabbage peroxidase

The partially purified peroxidase from waste cabbage showed an optimum temperature of 30 °C ( Fig. 3 ). A rapid and

progressive increase in peroxidase activity with an increase in temperature, and reaches a peak at a temperature of 30 °C.

The sharp decline in peroxidase activity with as the temperature progresses beyond 30 °C with a near or total loss of activity

at a temperature of 60–90 °C.

6

Jaylin Wares

E.B. Joel, S.G. Mafulul, H.E. Adamu et al. Scientific African 10 (2020) e00608

Fig. 2. The effect of varying pH on the activities of waste cabbage peroxidase. The change in A416 was converted to peroxidase activity (see Table 1 legend)

and expressed as relative activity (percentage) taking optimum activity as 100%.

Fig. 3. The effect of varying temperature on the activity of waste cabbage peroxidase.

Thermal stability of waste cabbage peroxidase

The thermal stability of waste cabbage peroxidase is as shown in Fig. 4 . After incubation at 50, 60, 70, and 80 °C for 3 h,

the results showed that waste cabbage leave peroxidase was highly stable at the tested temperatures ( Fig. 4 ) with up to 41%

original activity retained at 80 °C after 3 h incubation.

Substrate specificity and kinetics studies of waste cabbage peroxidase

To determine the substrate preference and kinetics of WC, peroxidase activity was assayed for at varying concentrations

(1.0–10 mM) of three tested substrates (O-dianisidine, guaiacol). Figs. 5 , 6 , and 7 showed the Lineweaver-Burk plot using

ABTS, guaiacol, and O-dianisidine respectively. Findings from this study showed that the maximum velocity (V max ) of ABTS

by waste cabbage peroxidase was highest followed by guaiacol and O-dianisidine with the least ( Table 2 ). On the other hand,

Km values follow the reverse order O-dianisidine > guaiacol > ABTS. This trend of Km values suggests that the affinity of the

partially purified enzyme towards the tested substrates follows this trend; ABTS > guaiacol > O -dianisidine.

7

E.B. Joel, S.G. Mafulul, H.E. Adamu et al. Scientific African 10 (2020) e00608

Fig. 4. Thermal stability of waste cabbage peroxidase. Peroxidase activity was expressed as residual activity (percentage) taking WCP activity without the

pre-incubation for 1 hour as 100% (control).

Fig. 5. Analysis of the effects of ABTS on the activities of waste cabbage peroxidase. (A) . A plot of enzyme activity versus ABTS concentrations. (B) .

Lineweaver-Burk plot of ABTS hydrolyzes catalyzed by waste cabbage peroxidase. The reciprocal of peroxidase activity and substrate concentrations were

calculated (Lineweaver-Burk plot).
8

E.B. Joel, S.G. Mafulul, H.E. Adamu et al. Scientific African 10 (2020) e00608

Fig. 6. Analysis of the effects of Guaiacol on the activities of waste cabbage peroxidase. (A) . A plot of enzyme activity versus Guaiacol concentrations.

(B) . Lineweaver-Burk plot of Guaiacol hydrolyzes catalyzed by waste cabbage peroxidase. The reciprocal of peroxidase activity and substrate concentrations

were calculated (Lineweaver-Burk plot).

Table 2

Kinetic parameters of waste cabbage peroxidase.

The K m and V max values were calculated from the

equation of the straight line of the Lineweaver-Burk

plots ( Figs. 5 , 6 , and 7 ) (see section 2.9 for the

translated formulae and equation).

Substrate Kinetic Parameters

K m (mM) V max (mM/min.)

O-dianisidine 19.24 588.24

Guaiacol 17.82 909.09

ABTS 1.24 1111.

11

Effects of metal ions, organic solvent (acetone), and chemicals (EDTA and urea) on waste cabbage peroxidase

To determine the effects of metal ions, acetone, EDTA, and urea on peroxidase activity, the WCP was pre-incubating with

an individual divalent metal ion, EDTA, acetone, and urea a final concentration of 5 mM for 30 min at 30 °C; the perox-

idase activity in the absence of metal ion, EDTA and acetone was taken as the control. Table 3 showed the effect of the

divalent metal ions (Hg 2 + , Zn

2 + , Cu

2 + , Mn

2 + , Ni 2 + ), acetone, and chemicals (EDTA and urea) in cabbage waste peroxidase.

The result suggests that the tested three metal ions, Hg 2 + , Cu

2 + , Ni 2 + and, organic solvent and chemicals exerted an in-

9

E.B. Joel, S.G. Mafulul, H.E. Adamu et al. Scientific African 10 (2020) e00608

Fig. 7. Analysis of the effects of O-dianisidine on the activities of waste cabbage peroxidase. (A) . A plot of enzyme activity versus O-dianisidine concen-

trations. (B) . Lineweaver-Burk plot of O-dianisidine hydrolyzes catalyzed by waste cabbage peroxidase. The reciprocal of peroxidase activity and substrate

concentrations were calculated (Lineweaver-Burk plot).

Table 3

Effects of metal ions, organic solvent (acetone), and chemicals (EDTA and urea)

on waste cabbage peroxidase. Residual peroxidase activities (%) were calculated

as = [(peroxidase activity in the presence of metal ion, EDTA, acetone, urea /the

peroxidase activity in the absence of metal ion, EDTA, acetone, urea)] ∗100.

Reagents (5 mM) Peroxidase activity (mmole/min.) Residual activity

(%)

Control (none) 2.755 100

Hg 2 + 2.02 73.3

Mn 2 + 3.175 115.2

Zn 2 + 2.835 102.9

Cu 2 + 1.515 55.0

Ni 2 + 2.23 80.9

EDTA 2.65 96.2

acetone 1.76 63.9

Urea 1.51 54.8

10

E.B. Joel, S.G. Mafulul, H.E. Adamu et al. Scientific African 10 (2020) e00608

Fig. 8. Percentage decolorization of various synthetic dyes by waste cabbage leaves peroxidase.

Table 4

Effect of waste cabbage peroxidase on the degradation of phenol. The phenol concentrations were estimated using the equation of

the straight line of the calibration curve for phenol ( Fig. 9 ). See section 2.11.2 for the calculation for percentage phenol degradation.

Initial phenol conc.

(mg/L)

Partially purified cabbage

peroxidase (mL)

Final Phenol

conc. (mg/L)

Residual Phenol conc.

(%)

% Phenol degradation

or removal

10 0 9.9 100.0 1.2

10 1 6.2 62.6 38.2

10 2 4.0 40.4 60.1

10 4 1.5 15.4 84.8

10 8 0.9 14.4 91.1

hibitory effect. The peroxidase activity was slightly enhanced by Mn

2 + and Zn

2 + with residual activity of 115.2% and 102.9%

respectively.

Application waste cabbage leaves peroxidase in biodegradation of phenol and synthetic dyes

Waste cabbage peroxidase mediated decolorization of synthetic dyes

The results showed that the absorbance peaks of the tested dyes were recorded at the following wavelengths alone azo

Yellow 6 (534 nm), azo Citrus Red 2 (525 nm), azo Purple (268 nm), and azo Blue 5 (648 nm). To investigate the abil-

ity of partially purified waste cabbage leaves peroxidase to decolorize different types of hazardous dyes, citrus red, azo

purple, azo yellow, and azo blue after 30 min, 1 hour, 24 h, and 48 h. The results showed that the waste cabbage perox-

idase was able to decolorize all the tested dyes at varying degrees ( Fig. 8 ). The result suggests that the partially purified

waste cabbage peroxidase was very efficient in the decolorization of azo dyes. It was observed that the% decolorization

of all the tested azo dyes increased with an increase in the incubation period. The extent of decolorization achieved with

different classes of dyes followed this trend, azo blue 5 (85.1) > azo purple (69.1) > azo yellow 6 (46.2) > azo citrus red

2 (42.9).

Waste cabbage peroxidase mediated phenol degradation

The calibration curve of the phenol standard ( Fig. 9 ) was used to quantify the residual phenol concentration after treat-

ment with WCP. The sharp increase in phenol conversion as the volume of the partially purified waste cabbage peroxidase

was increased ( Table 4 ). The optimum reaction conditions for waste cabbage leaves peroxidase were used to guarantee the

high efficiency of phenol degradation.

The result suggests that the partially purified waste cabbage leaves peroxidase was very efficient in the degradation of

phenol with over 60% phenol degradation observed after treatment with ≥ 2 ml of waste cabbage peroxidase.

11

E.B. Joel, S.G. Mafulul, H.E. Adamu et al. Scientific African 10 (2020) e00608

Fig. 9. Calibration curve of phenol standard. The plot of the corresponding absorbance values against the concentrations of phenol (calibration curve) was

used to extrapolate the residual phenol concentration after treatment with WCP.

Discussion

Peroxidase from waste cabbage was extracted, partially purified, characterized biochemical properties, and its potential

to biodegrade phenol and synthetic azo dyes from aqueous solution evaluated. Previously studies revealed that peroxidases

from different sources have variable optimum temperature and pH. The 30 °C optimum temperature for waste cabbage leaves

peroxidase reported in this work agrees with the previous report of Abbas [57] for fresh cabbage leaves peroxidase, Broccoli

( Brassica oleracea l. Var. Italica ) Stems peroxidase [40] , Jatropha curcas leaves peroxidase [58] which all displayed optimum

activity at 30 °C. [59] , also reported an optimum temperature range around 25- 40 °C for garlic ( Allium sativum ). Peroxidases

purified from other sources, however, have relatively higher optimum temperatures such as Calotropis Procera leaves peroxi-

dase [60] and M. oleifera leaves peroxidase [41] . Results for thermal stability profiles suggest that waste cabbage peroxidase

is a thermostable enzyme up to 80 °C, with 41% original activity retained after 3 h incubation. Thermal stability decreases as

the temperature increases. The residual peroxidase activity reported for date palm leaves ( Phoenix dactylifera L.) peroxidase

was higher than the observed 15% for this study at 80 °C after 60 min incubation period [61] . Previous findings have shown

that the inactivation of peroxidases at higher temperatures is likely to be a result of the unfolding of the tertiary structure

enzyme [61] .

The optimum pH and stability of WCP were comparable to that of peroxidase of date palm leaves ( Phoenix dactylifera L.)

[61] . Previous other studies also suggest that most peroxidases isolated from different sources exhibit optimum activity

in the pH range of 4.5- 6.5 [62–64] . Findings from this study showed a sharp decrease in extreme acidic and alkaline

pH peroxidase activity and stability. The pH usually affects the ionic state of the side chain of the enzyme’s amino acids.

Therefore, the effect at pH on the peroxidase activity and stability could be due to changes in the ionic state of amino acids

side chain at the active site which invariably affects heme-binding at low pH. Also, a decrease in activity and stability at

high and low pH values could be as a result of ionic changes in the heme group [61 , 65] .

The inhibitory effects of the tested metal ions (Hg 2 + , Cu

2 + , Ni 2 + ) and chemicals follow a similar trend with earlier reports

of [66] and [67] for Calotropis procera leaves peroxidase and Moringa oleifera leaves peroxidase respectively. EDTA is a well-

known chelating agent. This inhibitory effect exerted by EDTA could be by chelating iron (ii) atom (Fe 2 + ) at the active center

of the enzyme [68] . The inhibitory effect of Hg 2+ and other metal ions such as Cu

2 + , Ni 2 + may be as a result of binding to

SH groups present in the actives side of the enzyme thereby causing irreversible inactivation [69] . The activation of partially

purified peroxidase activity by Mn

2 + and Zn

2 + is in agreement with the previous reports of Al-Senaidy and Ismael [70] for

date palm leaves ( Phoenix dactylifera L .) peroxidase. Also, this enzyme is fairly stable in the presence of an organic solvent,

acetone, which further widens the applicability of waste cabbage leaves peroxidase for the treatment against a variety of

organic pollutants present in industrial and crude oil spilled wastewaters.

The kinetic data revealed that waste cabbage leaves peroxidase obeyed first-order reaction kinetics. The high turnover

rate and low K m

value of the partially purified waste cabbage leaves peroxidase towards ABTS follows a similar trend with

the substrate specificity result of this study that ABTS is the best substrate followed by guaiacol then O-dianisidine. Lower

Km values suggest that the enzyme has a high apparent affinity toward a substrate [61] . Although the K m

values were

higher than the ones reported for spring cabbage peroxidase [71] , for date palm leaves ( Phoenix dactylifera L .) peroxidase

12

Jaylin Wares

E.B. Joel, S.G. Mafulul, H.E. Adamu et al. Scientific African 10 (2020) e00608

[61] and Moringa oleifera leaves peroxidase [41] . However, high K m

values were reported for peroxidases from Calotropis

procera leaves [66] , Zea mays L waste [72] , garlic Allium sativum [73] wheat ( Triticum aestivum ssp. vulgare) [74] .

Phenol, substituted-phenol derivatives in azo dyes constitute hazardous compounds found in wastewaters of a wide va-

riety of industries [75] . Peroxidases have been reported to decrease environmental pollution via oxidation degradation phe-

nols, cresols and chlorinated phenols, and synthetic textile azo-dyes present in industrial effluent [18 , 76] . Enzymatic treat-

ment of phenolic pollutants is usually by the transformation of total phenol concentration into less biodegradable polymeric

compounds that could be removed by coagulation [77] . Findings from this study have shown significant potential and ca-

pacity of waste cabbage peroxidase for biodegradation of phenol from aqueous solution at the laboratory scale. The high

efficiency of this enzyme in phenol removal observed in this study is under optimum reaction conditions for the enzyme

obtained from the characterization studies. The reduction in phenol concentration with an increase in the volume of the

partially purified WCP indicates that it is caused by peroxidase oxidation of phenol. [78] , also reported on the role of perox-

idase as an enzymatic method for the removal of phenol from industrial effluent. However, the% removal of phenol by waste

cabbage leaves peroxidase was slightly lower than the one’s reports by [79] for horseradish ( cochlearia armoracia l) peroxi-

dase and [80] for immobilized turnip peroxidase. The slightly higher% removal of phenol in the previous reports compared

to this could be due to immobilization, presence of polyethylene glycol, or longer reaction period.

The rate of dye decolorization by waste cabbage leaves peroxidase varies due to the nature of the tested dyes. The high

efficiency of decolorization azo dyes as seen in this study was also reported by [81] for peroxidase partially purified from

garlic . After 4 h of incubation with Momordica charantia peroxidase, 23% decolorization of tannery effluent dyes was also

reported by [82 , 83] , reported 90% decolorization of naphthol blue after 5minutes by horseradish peroxidase. Husain et al.

[19] , also reported 85% decolorization of textile effluent dyes fenugreek peroxidase after 5 h of incubation. Therefore, the

variations in the time course of removal of these dyes as reported by various researchers might be due to the structural

barrier and electron localization among the dyes and the level of purification and concentration of peroxidase used for

decolorization.

The future research perspectives of this work

This study successfully demonstrated the possibility of recycling decaying waste cabbage contributing to an environ-

mental nuisance as a cost-effective source of a valuable enzyme, peroxidase that could potentially be explored for the

biodegradative treatment of toxic dye and phenolic pollutants present in industrial effluents such as oil spilled contaminated

water and soil in the Niger Delta of Nigeria. Nevertheless, to exploit the WCP for large-scale practical industrial application,

further research may focus on the following:

i Advanced purification of WCP, immobilization, and optimization of degradation reaction conditions to better understand

the factors affecting the performance of this enzyme in biodegradation of dyes and phenolic pollutants.

ii Analysis of degraded products of azo dyes and phenol by TLC, HPLC, FTIR, and GC–MS to ascertain the possible mecha-

nism of WCP mediated biodegradation.

iii Employ WCP for biodegradation of dyes and phenols from actual industrial effluent as well as the assessment of toxicity

of the degraded products and chemical oxygen demand (COD) and biological oxygen demand (BOD), and total oxygen

capacity (TOC) during treatment to understand the applicability of the developed process.

Conclusion

The present study demonstrated the prospect of transforming a heap agro-based waste in the agro market that consti-

tutes a source of environmental nuisance into a valuable product like peroxidase enzyme that could be deployed for biore-

mediation of industrial effluent. This study successfully extracted and partially purified peroxidase from a readily abundant

waste cabbage. Characterization of biochemical properties that the partially purified enzyme had its optimum activity at

temperature 30 °C, pH 5.5 while showing broad substrate preference. The WCP was stable over a wide range of pH (4.0 −7.0)

and its ability to retained 41% of its original activity at 80 °C indicates that it is a thermostable enzyme. The kinetic data

of WCP showed K m

values of 1.24, 17.89, and 19.24 mM and Vax values of 1111.11, 909.09, and 588.24 mM /minutes for

ABTS, guaiacol, and o-dianisidine respectively. Three metal ions, Hg 2 + , Cu

2 + , Ni 2 + , organic solvent (acetone), EDTA, and urea

inhibited peroxidase activity; whereas Mn

2 + and Zn

2 + showed slight activation. The partially purified WCP exhibited high

efficiency for the biodegradation of the tested synthetic azo dyes and phenol at the lab-scale. After 48 h of incubation, the

waste cabbage peroxidase efficiently catalyzed the decolorization of the different dyes such as azo blue 5, azo purple, azo

Yellow 6, and citrus red 2, with a percentage decolorization of 85.1, 69.1, 46.2 and 42.9%, respectively. The waste cabbage

peroxidase also shows up to 91.1% efficiency for degradation of phenol in aqueous solution after 60 min of reactions. The

significant increase in the% degradation of tested azo dyes and phenol from aqueous solution with an increasing volume of

the WCP suggests that this enzyme was responsible for the observed changes. Findings from this study provide promising

evidence on the possibility of utilizing waste cabbage as a good source peroxidase with the ability to biodegrade azo dyes

and phenol at a small scale in the laboratory. This study, therefore, increases the possibility of recycling waste cabbage and

other agro-waste for isolation of peroxidase as well as other bioproducts that can be useful for the treatment of industrial

effluents containing dye and phenolic pollutants.

13

E.B. Joel, S.G. Mafulul, H.E. Adamu et al. Scientific African 10 (2020) e00608

Declaration of Competing Interest

The authors declare that they have no known competing financial interests or personal relationships that could have

appeared to influence the work reported in this paper.

Funding

This research was not supported by any funding source.

References

[1] C.H. Chen, C.F. Chang, C.H. Ho, T.L. Tsai, S.M. Liu, Biodegradation of crystal violet by a Shewanella sp. NTOU1, Chemosphere 72 (2008) 1712–1720,
doi: 10.1016/j.chemosphere.2008.04.069 .

[2] M. Islam, M. Mostafa, Textile dyeing effluents and environment concerns – a review, J. Environ. Sci. Nat. Resour. 11 (2019) 131–144, doi: 10.3329/jesnr.
v11i1-2.43380 .

[3] B. Viswanath, B. Rajesh, A. Janardhan, A.P. Kumar, G. Narasimha, Fungal laccases and their applications in bioremediation, Enzyme Res. 2014 (2014),
doi: 10.1155/2014/163242 .

[4] B. Viswanath, M. Chandra, K. Kumar, B. Reddy, Production and purification of laccase from Stereum ostrea and its ability to decolorize textile dyes, Dyn.

Biochem. Process Biotechnol. Mol. Biol. 2 (2008) 19–25 http://scholar.google.com/scholar?hl=en&btnG=Search&q=intitle:Production+and+Purification+
of+Laccase+from+Stereum+ostrea+and+its+Ability+to+Decolorize+Textile+Dyes#0 .

[5] S.J. Allen, B. Koumanova, Decolourisation of water/wastewater using adsorption, J. Univ. Chem. Technol. Metall. 40 (2005) 175–192 – References – Sci-
entific Research Publishing, (n.d.). https://www.scirp.org/(S(351jmbntvnsjt1aadkposzje))/reference/ReferencesPapers.aspx?ReferenceID=1325646 . (ac-

cessed September 28, 2020) .
[6] R.S. Peixoto, A.B. Vermelho, A.S. Rosado, Petroleum-degrading enzymes: bioremediation and new prospects, Enzyme Res. 2011 (2011), doi: 10.4061/

2011/475193 .

[7] E. Bazrafshan, F.K. Mostafapour, H. Faridi, M.A. Zazouli, Application of Moringa peregrina seed extract as a natural coagulant for phenol removal from
aqueous solutions, African J. Biotechnol. 11 (2012) 16758–16766, doi: 10.5897/AJB12.1779 .

[8] T. Chiong , S. Lau , E. Khor , M. Danquah , Enzymatic approach to phenol removal from wastewater using peroxidases, OA Biotechnol 10 (2014) 1–6 .
[9] P. Kolhe, S. Ingle, N. Wagh, Degradation of phenol containing wastewater by advance catalysis system – a review, Annu. Res. Rev. Biol. 8 (2015) 1–15,

doi: 10.9734/arrb/2015/19936 .
[10] M.M. Sahasrabudhe, R.G. Saratale, G.D. Saratale, G.R. Pathade, Decolorization and detoxification of sulfonated toxic diazo dye C.I. direct red 81 by

enterococcus faecalis YZ 66, J. Environ. Health Sci. Eng. 12 (2014) 1–13, doi: 10.1186/s40201- 014- 0151- 1 .

[11] S. Nouren, H.N. Bhatti, Mechanistic Study of Degradation of Basic Violet 3 By Citrus Limon Peroxidase and Phytotoxicity Assessment of Its Degradation
Products, Elsevier B.V., 2015, doi: 10.1016/j.bej.2014.11.021 .

[12] E. Miland , M.R. Smyth , C.Ó. Fágáin , Phenol removal by modified peroxidases, J. Chem. Technol. Biotechnol. 67 (1996) 227–236 .
[13] P. Ramachandran, R. Sundharam, J. Palaniyappan, A.P. Munusamy, Potential process implicated in bioremediation of textile effluents: a review, Pelagia

Res. Libr. Adv. Appl. Sci. Res. 4 (2013) 131–145 www.pelagiaresearchlibrary.com .
[14] G. Parshetti, G. Saratale, A. Telke, S. Govindwar, Biodegradation of hazardous triphenylmethane dye methyl violet by Rhizobium radiobacter (MTCC

8161), J. Basic Microbiol. 49 (2009) 36–42, doi: 10.1002/jobm.200800200 .
[15] G.D. Saratale, R.G. Saratale, J.S. Chang, S.P. Govindwar, Fixed-bed decolorization of Reactive Blue 172 by Proteus vulgaris NCIM-2027 immobilized on

Luffa cylindrica sponge, Int. Biodeterior. Biodegrad. 65 (2011) 494–503, doi: 10.1016/j.ibiod.2011.01.012 .

[16] M. Pletsch, B.S. De Araujo, B.V. Charlwood, Novel biotechnological approaches in environmental remediation research, Biotechnol. Adv. 17 (1999) 679–
687, doi: 10.1016/S0734-9750(99)0 0 028-2 .

[17] P. Verma, D. Madamwar, Production of ligninolytic enzymes for dye decolorization by cocultivation of white-rot fungi pleurotus ostreatus and phane-
rochaete chrysosporium under solid-state fermentation, in: Applied Biochemistry and Biotechnology: Part A, Enzyme Engineering and Biotechnology,

Springer, 2002, pp. 109–118, doi: 10.1385/ABAB:102- 103:1- 6:109 .
[18] N. Bansal, S.S. Kanwar, Peroxidase(s) in environment protection, Sci. World J. 2013 (2013), doi: 10.1155/2013/714639 .

[19] Q. Husain, Z. Karim, Z.Z. Banday, Decolorization of textile effluent by soluble fenugreek (trigonella foenum-graecum L) seeds peroxidase, Water. Air.

Soil Pollut. 212 (2010) 319–328, doi: 10.1007/s11270-010-0345-9 .
[20] E. Miranda-Mandujano, G. Moeller-Chávez, O. Villegas-Rosas, G. Buitrón, M.A. Garzón-Zúñiga, Decolourization of direct blue 2 by peroxidases obtained

from an industrial soybean waste, Water SA 44 (2018) 204–210, doi: 10.4314/wsa.v44i2.06 .
[21] A. Brill , Peroxidase and Catalase. In: florkin and Stotz, Editors, (3rd ed.), Comp. Biochem. 14 (1971) 447–479 .

[22] M.A. Zia, M. Kousar, I. Ahmed, H.M. Nasir Iqbal, R.Z. Abbas, Comparative study of peroxidase purification from apple and orange seeds, Afr. J. Biotechnol.
10 (2011) 6300–6303, doi: 10.5897/AJB10.2675 .

[23] N.C. Veitch, A.T. Smith, Horseradish peroxidase, Adv. Inorg. Chem. 51 (20 0 0) 107–162, doi: 10.1016/S0898-8838(0 0)510 02-2 .

[24] W. Adam, M. Lazarus, C.R. Saha-Möller, O. Weichold, U. Hoch, D. Häring, P. Schreier, Biotransformations with peroxidases., Adv. Biochem. Eng. Biotech-
nol. 63 (1999) 73–108 http://www.ncbi.nlm.nih.gov/pubmed/9933982 . (accessed April 25, 2019) .

[25] N.C. Veitch, Horseradish peroxidase: a modern view of a classic enzyme., Phytochemistry 65 (2004) 249–259 http://www.ncbi.nlm.nih.gov/pubmed/
14751298 . (accessed April 25, 2019) .

[26] U.U. Jadhav, V.V. Dawkar, A .A . Telke, S.P. Govindwar, Decolorization of Direct Blue GLL with enhanced lignin peroxidase enzyme production in Coma-
monas sp UVS, J. Chem. Technol. Biotechnol. 84 (2009) 126–132, doi: 10.1002/jctb.2017 .

[27] S. Dalal, M.N. Gupta, Treatment of phenolic wastewater by horseradish peroxidase immobilized by bioaffinity layering, Chemosphere 67 (2007) 741–

747, doi: 10.1016/J.CHEMOSPHERE.2006.10.043 .
[28] Y.C. Lai, S.C. Lin, Application of immobilized horseradish peroxidase for the removal of p-chlorophenol from aqueous solution, Process Biochem. (2005)

http://agris.fao.org/agris-search/search.do?recordID=US201301045463 . (accessed April 25, 2019) .
[29] A.M. Azevedo, V.C. Martins, D.M.F. Prazeres, V. Vojinovi ́c, J.M.S. Cabral, L.P. Fonseca, Horseradish peroxidase: a valuable tool in biotechnology, Biotech-

nol. Annu. Rev. 9 (2003) 199–247, doi: 10.1016/S1387- 2656(03)09003- 3 .
[30] M. Saud Al-Bagmi, M. Shahnawaz Khan, M. Alhasan Ismael, A.M. Al-Senaidy, A. Ben Bacha, F. Mabood Husain, S.F. Alamery, An efficient methodology

for the purification of date palm peroxidase: stability comparison with horseradish peroxidase (HRP), Saudi J. Biol. Sci. 26 (2019) 301–307, doi: 10.1016/

J.SJBS.2018.04.002 .
[31] M.A. Alonso Lomillo, J.G. Ruiz, F.J.M. Pascual, Biosensor based on platinum chips for glucose determination, Anal. Chim. Acta 547 (2005) 209–214,

doi: 10.1016/J.ACA.2005.05.037 .
[32] S. Xu, H. Qi, S. Zhou, X. Zhang, C. Zhang, M.A. Alonso Lomillo, J.G. Ruiz, F.J.M. Pascual, Mediatorless amperometric bienzyme glucose biosensor

based on horseradish peroxidase and glucose oxidase cross-linked to multiwall carbon nanotubes, Microchim. Acta 181 (2014) 535–541, doi: 10.1007/
s00604- 014- 1175- z .

14

https://doi.org/10.1016/j.chemosphere.2008.04.069

https://doi.org/10.3329/jesnr.v11i1-2.43380

https://doi.org/10.1155/2014/163242

http://scholar.google.com/scholar?hl=en&btnG=Search&q=intitle:Production+and+Purification+of+Laccase+from+Stereum+ostrea+and+its+Ability+to+Decolorize+Textile+Dyes#0

https://www.scirp.org/(S(351jmbntvnsjt1aadkposzje))/reference/ReferencesPapers.aspx?ReferenceID=1325646

https://doi.org/10.4061/2011/475193

https://doi.org/10.5897/AJB12.1779

http://refhub.elsevier.com/S2468-2276(20)30345-8/sbref0008

http://refhub.elsevier.com/S2468-2276(20)30345-8/sbref0008

http://refhub.elsevier.com/S2468-2276(20)30345-8/sbref0008

http://refhub.elsevier.com/S2468-2276(20)30345-8/sbref0008

http://refhub.elsevier.com/S2468-2276(20)30345-8/sbref0008

https://doi.org/10.9734/arrb/2015/19936

https://doi.org/10.1186/s40201-014-0151-1

https://doi.org/10.1016/j.bej.2014.11.021

http://refhub.elsevier.com/S2468-2276(20)30345-8/sbref0012

http://refhub.elsevier.com/S2468-2276(20)30345-8/sbref0012

http://refhub.elsevier.com/S2468-2276(20)30345-8/sbref0012

http://refhub.elsevier.com/S2468-2276(20)30345-8/sbref0012

http://www.pelagiaresearchlibrary.com

https://doi.org/10.1002/jobm.200800200

https://doi.org/10.1016/j.ibiod.2011.01.012

https://doi.org/10.1016/S0734-9750(99)00028-2

https://doi.org/10.1385/ABAB:102-103:1-6:109

https://doi.org/10.1155/2013/714639

https://doi.org/10.1007/s11270-010-0345-9

https://doi.org/10.4314/wsa.v44i2.06

http://refhub.elsevier.com/S2468-2276(20)30345-8/sbref0021

http://refhub.elsevier.com/S2468-2276(20)30345-8/sbref0021

https://doi.org/10.5897/AJB10.2675

https://doi.org/10.1016/S0898-8838(00)51002-2

http://www.ncbi.nlm.nih.gov/pubmed/9933982

http://www.ncbi.nlm.nih.gov/pubmed/14751298

https://doi.org/10.1002/jctb.2017

https://doi.org/10.1016/J.CHEMOSPHERE.2006.10.043

http://agris.fao.org/agris-search/search.do?recordID=US201301045463

https://doi.org/10.1016/S1387-2656(03)09003-3

https://doi.org/10.1016/J.SJBS.2018.04.002

https://doi.org/10.1016/J.ACA.2005.05.037

https://doi.org/10.1007/s00604-014-1175-z

E.B. Joel, S.G. Mafulul, H.E. Adamu et al. Scientific African 10 (2020) e00608

[33] Y.-.M. Jeong, M.H. Oh, S.Y. Kim, H. Li, H.-.Y. Yun, K.J. Baek, N.S. Kwon, W.Y. Kim, D.-.S. Kim, Indole-3-acetic acid/horseradish peroxidase induces apopto-
sis in TCCSUP human urinary bladder carcinoma cells, Pharmazie 65 (2010) 122–126 http://www.ncbi.nlm.nih.gov/pubmed/20225657 . (accessed April

25, 2019) .
[34] M. Hamid, Khalil-ur-Rehman, Potential applications of peroxidases, Food Chem. 115 (2009) 1177–1186, doi: 10.1016/j.foodchem.2009.02.035 .

[35] C. Regalado, B.E. García-Almendárez, M.A. Duarte-Vázquez, Biotechnological applications of peroxidases, Phytochem. Rev. 3 (2004) 243–256, doi: 10.
1023/B:PHYT.0 0 0 0 047797.81958.69 .

[36] T. Chiong, S.Y. Lau, E.H. Khor, M.K. Danquah, Peroxidase extraction from jicama skin peels for phenol removal, IOP Conf. Ser. Earth Environ. Sci. 36

(2016), doi: 10.1088/1755-1315/36/1/012048 .
[37] A. Cardinali, D. Di Venere, L. Sergio, V. Linsalata, Characterization and partial purification of peroxidase from artichoke leaves, Acta Hortic. (2005)

445–452, doi: 10.17660/ActaHortic.2005.681.62 .
[38] X. Cheng, R. Jia, P. Li, S. Tu, Q. Zhu, W. Tang, X. Li, Purification of a new manganese peroxidase of the white-rot fungus Schizophyllum sp. F17, and

decolorization of azo dyes by the enzyme, Enzyme Microb. Technol. 41 (2007) 258–264, doi: 10.1016/j.enzmictec.2007.01.020 .
[39] B. Rusdi, D. Mulyanti, M. Rodiyah, Characterization of peroxidase enzyme from water spinach (Ipomoea Aquatica Forssk.) fraction, Proc. Chem. 13

(2014) 170–176, doi: 10.1016/j.proche.2014.12.022 .
[40] Q. Ahmad , A. Mehmood , Z. Saeed , M. Fayyaz , Purification and characterization of peroxidase from broccoli (Brassica oleracea l. Var . Italica), Stems 15

(2019) 38–45 .

[41] S. Khatun , R.K. Ashraduzzaman , F. Pervin , N. Absar , A. Rosma , Purification and characterization of peroxidase from moringa oleifera l. leaves, Biore-
sources 7 (2012) 3237–3251 .

[42] E. Clemente, Peroxidase from oranges (Citrus sinenses (L.) Osbeck, Eur. Food Res. Technol. 215 (2002) 164–168, doi: 10.10 07/s0 0217-0 02-0516-z .
[43] V.P. Pandey, S. Singh, R. Singh, U.N. Dwivedi, Purification and characterization of peroxidase from papaya (Carica papaya) fruit, Appl. Biochem. Biotech-

nol. 167 (2012) 367–376, doi: 10.1007/s12010- 012- 9672- 1 .
[44] P.P. Kharatmol , A.B. Pandit , Extraction, partial purification and characterization of acidic peroxidase from cabbage leaves (Brasicca olearacea var. capi-

tata), J. Biochem. Technol. 4 (2012) 531–540 .

[45] A. adnan Abbas , Extraction ، purification and characterization of peroxidase from cabbage, Iraqi J. Sci. 56 (2015) 2282–2291 .
[46] F.S. Hanschen, M. Kaufmann, F. Kupke, T. Hackl, L.W. Kroh, S. Rohn, M. Schreiner, Brassica vegetables as sources of epithionitriles: novel secondary

products formed during cooking, Food Chem. 245 (2018) 564–569, doi: 10.1016/j.foodchem.2017.10.124 .
[47] D.J. Shea, E. Itabashi, S. Takada, E. Fukai, T. Kakizaki, R. Fujimoto, K. Okazaki, The role of FLOWERING LOCUS C in vernalization of Brassica: the

importance of vernalization research in the face of climate change, Crop Pasture Sci. 69 (2018) 30, doi: 10.1071/CP16468 .
[48] B. Diyansah, L.Q. Aini, T. Hadiastono, The effect of PGPR (Plant Growth Promoting Rhizobacteria) pseudomonas fluorescens and bacillus subtilis on

leaf mustard plant (Brassica juncea L.) infected by TuMV (Turnip Mosaic Virus), J. Trop. Plant Prot. 1 (2017) 30–38 https://jtpp.ub.ac.id/index.php/jtpp/

article/view/102 . (accessed April 25, 2019) .
[49] FAOGlobal Food Losses and Food Waste – Extent, Causes and Prevention., 2011 Rome http://www.fao.org/3/a-i2697e .

[50] S.N. Misi, C.F. Forster, Semi-continuous anaerobic co-digestion of agro-wastes, Environ. Technol. 23 (2002) 445–451, doi: 10.1080/09593332508618405 .
[51] K.O. Omeje, C.C. Victor, S.O.O. Eze, A.L. Ezugwu, F.C. Chilaka, I.N.E. Onwurah, P.O. Ukoha, Decolorization of synthetic dyes using partially purified

peroxidase from green cabbage (Brassica oleracea), Songklanakarin J. Sci. Technol. 41 (2019) 783–787, doi: 10.14456/sjst-psu.2019.100 .
[52] M. Wadhwa, M.P.S. Bakshi, H.P.S. Makkar, Wastes to worth: value added products from fruit and vegetable wastes, CAB Rev. Perspect. Agric. Vet. Sci.

Nutr. Nat. Resour. 10 (2015), doi: 10.1079/PAVSNNR201510043 .

[53] T.H. Arvanitoyannis , I.S. Varzakas , Vegetable waste management: treatment methods and potential uses of treated waste, Manag. Treat. Methods Treat.
Waste (2002) 703–756 .

[54] Z. Geng, K.J. Rao, A.S. Bassi, M. Gijzen, N. Krishnamoorthy, Investigation of biocatalytic properties of soybean seed hull peroxidase, Catal. Today. 64
(2001) 233–238, doi: 10.1016/S0920-5861(0 0)0 0527-7 .

[55] H. Lowry., The Folin by Oliver, Anal. Biochem. 217 (1994) 220–230, doi: 10.1016/0304-3894(92)87011-4 .
[56] J. Łobarzewski, M. Brzyska, A. Wójcik, B. Kolarz, The influence of metal ions on the soluble and immobilized cytoplasmic cabbage peroxidase activity

and its kinetics, J. Mol. Catal. 59 (1990) 373–383, doi: 10.1016/0304-5102(90)85109-U .

[57] A. adnan Abbas , Extraction ، purification and characterization of peroxidase from cabbage, Iraqi J. Sci. 56 (2015) 2282–2291 .
[58] P. Duan, F. Cai, Y. Luo, Y. Chen, S. Zou, Long-term chemiluminescence signal is produced in the course of luminol oxidation catalyzed by enhancer-

independent peroxidase purified from Jatropha curcas leaves, Luminescence 30 (2015) 818–822, doi: 10.1002/bio.2825 .
[59] S.M. Marzouki, F. Limam, M.I. Smaali, R. Ulber, M.N. Marzouki, A new thermostable peroxidase from garlic allium sativum: purification, biochemical

properties, immobilization, and use in H 2 O 2 detection in milk, Appl. Biochem. Biotechnol. 127 (2005) 201–214 http://www.ncbi.nlm.nih.gov/pubmed/
16377850 . (accessed April 25, 2019) .

[60] S.G. Mafulul, E.B. Joel, L.A. Barde, J.L. Lenka, A .A . Ameh, M.G. Phililus, J. Chiang, Extraction, partial purification and characterization of peroxidase from

calotropis procera leaves, J. Adv. Biol. Biotechnol. India 18 (2018) 1–10, doi: 10.9734/JABB/2018/41709 .
[61] A .M. Al-Senaidy, M.A . Ismael, Purification and characterization of membrane-bound peroxidase from date palm leaves (Phoenix dactylifera L.), Saudi J.

Biol. Sci. 18 (2011) 293–298, doi: 10.1016/j.sjbs.2011.04.005 .
[62] J.C. Leon, I. Alpeeva, T. Chubar, I.Y. Galaev, E. Csoregi, I.Y. Sakharov, Purification and substrate specificity of peroxidase from sweet potato tubers, Plant

Sci. 163 (2002) 1011–1019, doi: 10.1016/S0168- 9452(02)00275- 3 .
[63] S.S. Deepa, C. Arumughan, Purification and characterization of soluble peroxidase from oil palm (Elaeis guineensis Jacq.) leaf, Phytochemistry 61 (2002)

503–511, doi: 10.1016/S0 031-9422(02)0 0167-X .
[64] I.Y. Sakharov, M.K. Vesga Blanco, I.V. Sakharova, Substrate specificity of African oil palm tree peroxidase, Biochemistry 67 (2002) 1043–1047, doi: 10.

1023/A:1020534321683 .

[65] J.B. Adams, Regeneration and the kinetics of peroxidase inactivation, Food Chem. 60 (1997) 201–206, doi: 10.1016/S0308- 8146(96)00320- 2 .
[66] S. Mafulul, E. Joel, L. Barde, J. Lenka, A. Ameh, M. Phililus, Extraction, partial purification and characterization of peroxidase from calotropis procera

leaves, J. Adv. Biol. Biotechnol. 18 (2018) 1–10, doi: 10.9734/jabb/2018/41709 .
[67] S. Khatun , R.K. Ashraduzzaman , F. Pervin , N. Absar , A. Rosma , Purification and characterization of peroxidase from moringa oleifera l. leaves, Biore-

sources 7 (2012) 3237–3251 .
[68] R. De ̧ bowska, A. Podstolski, Properties of diphenolase from Vanilla planifolia (Andr.) shoot primordia cultured in vitro, J. Agric. Food Chem. 49 (2001)

3432–3437, doi: 10.1021/jf001180z .

[69] B.L. Vallee, D.D. Ulmer, Biochemical effects of mercury, cadmium, and lead, Annu. Rev. Biochem. 41 (1972) 91–128, doi: 10.1146/annurev.bi.41.070172.
0 0 0515 .

[70] A .M. Al-Senaidy, M.A . Ismael, Purification and characterization of membrane-bound peroxidase from date palm leaves (Phoenix dactylifera L.), Saudi J.
Biol. Sci. 18 (2011) 293–298, doi: 10.1016/j.sjbs.2011.04.005 .

[71] A. Belcarz, G. Ginalska, B. Kowalewska, P. Kulesza, Spring cabbage peroxidases – Potential tool in biocatalysis and bioelectrocatalysis, Phytochemistry
69 (2008) 627–636, doi: 10.1016/J.PHYTOCHEM.2007.08.018 .

[72] S. Lakshmi, G.M. Shashidhara, G.M. Madhu, R. Muthappa, H.K. Vivek, M.N. Nagendra Prasad, Characterization of peroxidase enzyme and detoxification

of phenols using peroxidase enzyme obtained from Zea mays L waste, Appl. Water Sci. 8 (2018) 1–7, doi: 10.1007/s13201- 018- 0820- 9 .
[73] L. Banci, Structural properties of peroxidases, J. Biotechnol. 53 (1997) 253–263, doi: 10.1016/S0168-1656(97)01677-5 .

[74] S. Altın, H. Tohma, İ. Gülçin, E. Köksal, Purification, characterization, and inhibition sensitivity of peroxidase from wheat (Triticum aestivum ssp.
vulgare), Int. J. Food Prop. 20 (2017) 1949–1959, doi: 10.1080/10942912.2016.1225308 .

[75] M. Hamid, Khalil-ur-Rehman, Potential applications of peroxidases, Food Chem. 115 (2009) 1177–1186, doi: 10.1016/j.foodchem.2009.02.035 .

15

http://www.ncbi.nlm.nih.gov/pubmed/20225657

https://doi.org/10.1016/j.foodchem.2009.02.035

https://doi.org/10.1023/B:PHYT.0000047797.81958.69

https://doi.org/10.1088/1755-1315/36/1/012048

https://doi.org/10.17660/ActaHortic.2005.681.62

https://doi.org/10.1016/j.enzmictec.2007.01.020

https://doi.org/10.1016/j.proche.2014.12.022

http://refhub.elsevier.com/S2468-2276(20)30345-8/sbref0040

http://refhub.elsevier.com/S2468-2276(20)30345-8/sbref0040

http://refhub.elsevier.com/S2468-2276(20)30345-8/sbref0040

http://refhub.elsevier.com/S2468-2276(20)30345-8/sbref0040

http://refhub.elsevier.com/S2468-2276(20)30345-8/sbref0040

http://refhub.elsevier.com/S2468-2276(20)30345-8/sbref0041

http://refhub.elsevier.com/S2468-2276(20)30345-8/sbref0041

http://refhub.elsevier.com/S2468-2276(20)30345-8/sbref0041

http://refhub.elsevier.com/S2468-2276(20)30345-8/sbref0041

http://refhub.elsevier.com/S2468-2276(20)30345-8/sbref0041

http://refhub.elsevier.com/S2468-2276(20)30345-8/sbref0041

https://doi.org/10.1007/s00217-002-0516-z

https://doi.org/10.1007/s12010-012-9672-1

http://refhub.elsevier.com/S2468-2276(20)30345-8/sbref0045

http://refhub.elsevier.com/S2468-2276(20)30345-8/sbref0045

http://refhub.elsevier.com/S2468-2276(20)30345-8/sbref0045

http://refhub.elsevier.com/S2468-2276(20)30345-8/sbref0046

http://refhub.elsevier.com/S2468-2276(20)30345-8/sbref0046

https://doi.org/10.1016/j.foodchem.2017.10.124

https://doi.org/10.1071/CP16468

https://jtpp.ub.ac.id/index.php/jtpp/article/view/102

http://www.fao.org/3/a-i2697e

https://doi.org/10.1080/09593332508618405

https://doi.org/10.14456/sjst-psu.2019.100

https://doi.org/10.1079/PAVSNNR201510043

http://refhub.elsevier.com/S2468-2276(20)30345-8/sbref0054

http://refhub.elsevier.com/S2468-2276(20)30345-8/sbref0054

http://refhub.elsevier.com/S2468-2276(20)30345-8/sbref0054

https://doi.org/10.1016/S0920-5861(00)00527-7

https://doi.org/10.1016/0304-3894(92)87011-4

https://doi.org/10.1016/0304-5102(90)85109-U

http://refhub.elsevier.com/S2468-2276(20)30345-8/sbref0058

http://refhub.elsevier.com/S2468-2276(20)30345-8/sbref0058

https://doi.org/10.1002/bio.2825

http://www.ncbi.nlm.nih.gov/pubmed/16377850

https://doi.org/10.9734/JABB/2018/41709

https://doi.org/10.1016/j.sjbs.2011.04.005

https://doi.org/10.1016/S0168-9452(02)00275-3

https://doi.org/10.1016/S0031-9422(02)00167-X

https://doi.org/10.1023/A:1020534321683

https://doi.org/10.1016/S0308-8146(96)00320-2

https://doi.org/10.9734/jabb/2018/41709

http://refhub.elsevier.com/S2468-2276(20)30345-8/sbref0068

http://refhub.elsevier.com/S2468-2276(20)30345-8/sbref0068

http://refhub.elsevier.com/S2468-2276(20)30345-8/sbref0068

http://refhub.elsevier.com/S2468-2276(20)30345-8/sbref0068

http://refhub.elsevier.com/S2468-2276(20)30345-8/sbref0068

http://refhub.elsevier.com/S2468-2276(20)30345-8/sbref0068

https://doi.org/10.1021/jf001180z

https://doi.org/10.1146/annurev.bi.41.070172.000515

https://doi.org/10.1016/j.sjbs.2011.04.005

https://doi.org/10.1016/J.PHYTOCHEM.2007.08.018

https://doi.org/10.1007/s13201-018-0820-9

https://doi.org/10.1016/S0168-1656(97)01677-5

https://doi.org/10.1080/10942912.2016.1225308

https://doi.org/10.1016/j.foodchem.2009.02.035

E.B. Joel, S.G. Mafulul, H.E. Adamu et al. Scientific African 10 (2020) e00608

[76] S.T. Ong, P.S. Keng, W.N. Lee, S.T. Ha, Y.T. Hung, Dye waste treatment, Water (Basel) 3 (2011) 157–176, doi: 10.3390/w3010157 .
[77] M. Wagner, J.A. Nicell, Peroxidase-catalyzed removal of phenols from a petroleum refinery wastewater, Water Sci. Technol. 43 (2001) 253–260, doi: 10.

2166/wst.20 01.0 097 .
[78] N.S.J. Singh, An enzymatic method for removal of phenol from an enzymatic method for removal of phenol from, Prep. Biochem. Biotechnol. 32 (2002)

127–133, doi: 10.1081/PB-120 0 04125 .
[79] M. Stanisavljevi ́c, L. Nedi ́c, Removal of phenol from industrial wastewaters by horseradish-Cochlearia armoracia l -peroxidase, Facta Univ. Work 2

(2004) 345–349 http://scindeks.ceon.rs/article.aspx?artid=0354-804X0404345S .

[80] F. Quintanilla-Guerrero, M.A. Duarte-Vázquez, B.E. García-Almendarez, R. Tinoco, R. Vazquez-Duhalt, C. Regalado, Polyethylene glycol improves phenol
removal by immobilized turnip peroxidase, Bioresour. Technol. 99 (2008) 8605–8611, doi: 10.1016/j.biortech.2008.04.031 .

[81] A.C. Osuji, S.O.O. Eze, E.E. Osayi, F.C. Chilaka, Biobleaching of industrial important dyes with peroxidase partially purified from garlic, Sci. World J. 2014
(2014) 183163, doi: 10.1155/2014/183163 .

[82] G.V.S. Subramaniam, B. Ramesh, K. Kavitha, K. Vasu., Beetle (A ulacophora foveicollis) in bitter gourd, Recent Res. Sci. Technol. 2 (2010) 49–53 https:
//www.researchgate.net/publication/215732606 _ Bitter _ Gourd _ Momordica _ charantia _ Peroxidase _ in _ Decolorization _ of _ Dyes _ from _ Tannery _ Effluent .

[83] S. Onder, M. Celebi, M. Altikatoglu, A. Hatipoglu, H. Kuzu, Decolorization of naphthol blue black using the horseradish peroxidase, Appl. Biochem.
Biotechnol. 163 (2011) 433–443, doi: 10.1007/s12010-010- 9051- 8 .

16

https://doi.org/10.3390/w3010157

https://doi.org/10.2166/wst.2001.0097

https://doi.org/10.1081/PB-120004125

http://scindeks.ceon.rs/article.aspx?artid=0354-804X0404345S

https://doi.org/10.1016/j.biortech.2008.04.031

https://doi.org/10.1155/2014/183163

https://www.researchgate.net/publication/215732606_Bitter_Gourd_Momordica_charantia_Peroxidase_in_Decolorization_of_Dyes_from_Tannery_Effluent

https://doi.org/10.1007/s12010-010-9051-8

  • Peroxidase from waste cabbage (Brassica oleracea capitata L.) exhibits the potential to biodegrade phenol and synthetic dyes from wastewater
  • Introduction

    Materials and methods

    Materials and reagents

    Extraction of waste cabbage peroxidase

    Extraction of crude peroxidase from waste cabbage

    Thermal treatment of crude extract of waste cabbage peroxidase

    Peroxidase assay and protein determination

    Partial purification of crude peroxidase from waste cabbage

    Ammonium sulfate precipitation of crude waste cabbage peroxidase and dialysis

    Gel filtration chromatography

    Biochemical characterization of partially purified waste cabbage peroxidase properties

    Determination of the effect of pH on waste cabbage peroxidase activity and stability

    Determination of the effect of temperature on waste cabbage peroxidase activity and stability

    Kinetic constants/substrate specificity of waste cabbage leaves peroxidase

    Determination of the effect of chemicals and metal ions on waste cabbage peroxidase activity

    Application waste cabbage peroxidase in biodegradation of phenol and synthetic dyes

    Waste cabbage peroxidase mediated decolorization of synthetic dyes

    Waste cabbage peroxidase mediated biodegradation of synthetic phenol

    Data/Statistical analysis

    Results

    Purification of waste cabbage peroxidase

    Biochemical characterization of partially purified waste cabbage peroxidase

    Effect of pH on activity and stability of waste cabbage peroxidase

    Effect of varying temperature on the activity of waste cabbage peroxidase

    Thermal stability of waste cabbage peroxidase

    Substrate specificity and kinetics studies of waste cabbage peroxidase

    Effects of metal ions, organic solvent (acetone), and chemicals (EDTA and urea) on waste cabbage peroxidase

    Application waste cabbage leaves peroxidase in biodegradation of phenol and synthetic dyes

    Waste cabbage peroxidase mediated decolorization of synthetic dyes

    Waste cabbage peroxidase mediated phenol degradation

    Discussion

    The future research perspectives of this work

    Conclusion

    Declaration of Competing Interest

    Funding

    References

669 © IWA Publishing 2012 Water Science & Technology | 65.4 | 2012

Obtention of plant peroxidase and its potential

for the decolorization of the reactive dye Remazol

Turquoise G 133%

Maria Cristina Silva, Juliana Arriel Torres, Angelita Duarte Corrêa,

Allana Maria Bernardes Junqueira, Maria Teresa Pessoa Amorim

and Custódio Donizete dos Santos

ABSTRACT

Peroxidases can be used in the decolorization process. There is a growing interest for new sources of

this enzyme and for obtaining economically viable processes. In this work, a low-cost vegetable

peroxidase extraction process is proposed; the resulting enzyme is characterized to determine its

optimum pH, temperature, and stability conditions, and it is then applied in the decolorization of

reactive dye Remazol Turquoise G 133%. The turnip peroxidase (TP) was utilized as an enzymatic

source. This enzyme exhibited maximum activity at pH 7.0, and it was active in the temperature

range of 30 to 50 WC, which favors its use in industrial processes. Acetone was the most efficient

solvent to induce precipitation. The removal of Remazol Turquoise G 133% was 56.0% complete after

50 min, while 41.0% of the same dye was removed with the commercial horseradish peroxidase

enzyme in 50 min. TP presents potential as a viable alternative in the decolorization of textile

wastewaters.

doi: 10.2166/wst.2012.892

Maria Cristina Silva
Juliana Arriel Torres (corresponding author)
Angelita Duarte Corrêa
Allana Maria Bernardes Junqueira
Custódio Donizete dos Santos
Department of Chemistry,
Federal University of Lavras,
37200-000, Lavras, MG,
Brazil
E-mail: julianaarriel@hotmail.com

Maria Teresa Pessoa Amorim
Department of Textile Engineering,
University of Minho,
4800-058 Guimarães,
Portugal

Key words | decolorization, environmental biocatalysis, peroxidase, textile dyes, turnip

INTRODUCTION

The textile industry plays an important role in most
countries, being one of the traditional industrial segments.

However, textile processes consume large quantities of
water, chemical products and synthetic dyes, and they gener-
ate large volumes of wastewater that contain a high organic
load.

In general, it is believed that approximately 20% of the
dye load is lost in the dyeing residues during textile proces-
sing, which represents one of the great environmental

problems faced by the sector (Guarantini & Zanoni ).
Considering that more than 700 thousand tons of dyes and
pigments are produced annually in the world and that

Brazil is responsible for the consumption of about 2.6%
(Zanoni & Carneiro ), the harmful effect of the
liberation of dyes in the environment becomes quite
significant.

When not treated appropriately, and when discharged
in natural waters, the wastewaters originating from the dye
industry or processes involving the dyeing of textile fibers

can modify the ecosystem, reducing the transparency of
the water and the penetration of solar radiation, which

can reduce photosynthetic activity and the solubility of
gases.

In general, the textile industry uses treatment systems
based on physico-chemical and biological systems, which

in many cases are incompatible with the characteristics of
the wastewater generated, mainly with respect to the
removal of the color. From this point of view, the study of

new treatment alternatives is essential.
The peroxidases (donor H2O2 oxidoreductase, E.C.

1.11.1.7) are enzymes that catalyze the reduction of hydro-

gen peroxide or another organic peroxide when an
electron donor is oxidized. The reaction occurs in multiple
stages, as shown below:

PeroxidaseþH2O2 ! Compound IþH2O (1)

Compound Iþ AH2 ! Compound IIþA� (2)

mailto:julianaarriel@hotmail.com

670 M. C. Silva et al. | Obtention of peroxidase and its potential for decolorization Water Science & Technology | 65.4 | 2012

Compound IIþAH2 ! PeroxidaseþAH þH2O (3)

In the first stage of the catalytic process, the reaction of
the active site with hydrogen peroxide occurs. The hydrogen

peroxide is reduced, producing water and compound I, a
reactive intermediate that has a higher oxidation state than
the native enzyme. In the second stage of the reaction, com-

pound I oxidizes a substrate molecule (AH2), generating a
substrate radical and compound II. Finally, a second sub-
strate molecule reduces compound II, returning the
enzyme to its initial form (Hiner et al. ).

This class of enzymes is widely distributed in the plant
and animal kingdoms, and it is found in microorganisms,
plants and mammals (Veitch ).

Peroxidase has been used in biotechnology and several
other areas of science for the establishment of clinical diag-
noses, in the evaluation of pathological processes, in food

quality analysis, in the construction of biosensors for quali-
tative and quantitative analysis of pharmaceutical and
cosmetic formulas and in paper and cellulose manufactur-

ing. In the environment, the water pollution index can be
evaluated through tests using peroxidases. Furthermore,
these enzymes can be used in the decolorization process
to decrease textile industry pollutant residues (Maciel et al.
, ).

Besides the use in decolorization processes, peroxidases
can be used for the removal of phenolic compounds by oxi-

dizing them to phenoxy radicals, which then react to create
less soluble hydrophobic polymeric products (Li et al. ).
horseradish peroxidase has been utilized for the removal of

halogenated phenols (Meizler et al. ) and pentachloro-
phenol (Li et al. ). Other peroxidases, such as
peroxidases from Allium sativum, Ipomoea batatas, Rapha-
nus sativus, Sorghum bicolor and soybean peroxidase have

also been applied to phenol removal (Al-Ansari et al. ;
Diao et al. ).

The limitation on the use on plant peroxidases is the low

yield and high production cost compared with bacterial or
fungal enzymes. However, the production cost of these
enzymes can be reduced by optimizing the extraction con-

ditions and by using plant material with high enzymatic
activity that can be directly applied with the same efficiency
as the purified enzyme (Dec & Bollag ).

The peroxidases occur in the soluble and bonded form,
associated with the cell walls of plant cells and probably
associated with certain organelles (Khan & Robinson
). The soluble fraction can be extracted with water or

with a low ionic strength buffer, the ionically bonded

fraction with a high ionic strength buffer containing NaCl

or CaCl2, and the covalently bonded form using cellulolytic
or pectinolytic enzymes (Vámos-Vigyázó ).

The use of additives is advisable in the extraction of

plant enzymes. The chemical compounds that are usually
used include buffers, whose function is the protection of
the enzymes from acids liberated from the vacuoles after
the rupture of the cell and the desorption of the enzyme

bonded to the cell wall; PEG and PVP (polyvinylpolypyrro-
lidone), which protect against inactivation by phenols and
their oxidation products and EDTA as a chelator (Doonan

).
The most commonly used commercial peroxidase source

is horseradish (horseradish peroxidase), which is usually cul-

tivated and harvested in cold climate countries (Maciel et al.
). Several reports in the literature point to the use of
horseradish peroxidase in the degradation of several dyes:
(1) Mohan et al. () obtained 79% degradation of

acid black dye with the horseradish peroxidase immobilized
in acrylamide gel, and 67% with the free enzyme; (2)
Ferreira-Leitao et al. () studied the degradation of

methylene blue dye by horseradish peroxidase. In this work,
only 4.7% of the dye remained in solution, for a 1:10 pro-
portion of dye/H2O2; and (3) Bhunia et al. () showed

that horseradish peroxidase can be effective in the degra-
dation and precipitation of important industrial azo dyes.

Due to the widespread use of peroxidases, mainly as an

environmental biocatalyst, there is a growing interest in new
sources of this enzyme.

In this context, the objectives of this work included
obtaining a new vegetable source rich in peroxidase; the

determination of the optimum pH, temperature and stability
conditions of this enzyme, which are important parameters
to evaluate the potential application of the enzyme in indus-

trial processes; the evaluation of its potential in the
degradation of the reactive dye Remazol Turquoise G
133%; and a comparison with the degradation potential of

the commercial horseradish peroxidase enzyme.

METHODS

Vegetables, commercial enzyme and dye

The following vegetables were used to obtain the peroxi-
dase: turnip (Brassica campestre ssp. rapifera), radish

(Raphanus sativus), zucchini squash (Curcubita pepo),
gilo (Solanum gilo Raddi) and sweet potato (Ipomoea

671 M. C. Silva et al. | Obtention of peroxidase and its potential for decolorization Water Science & Technology | 65.4 | 2012

potatoes (L.) Lam.). The fruits of the squash and gilo, the

roots of the turnip and radish, the tuber of the sweet
potato, and the leaves and the peels of all the vegetables
were used.

The horseradish peroxidase enzyme (HPR II) was
acquired from Sigma Aldrich and used in aqueous solution
(30 mg of the commercial enzyme in 20 mL of 0.05 mol L�1

phosphate buffer, pH 6.5). After the preparation, the

enzyme was stored at an average temperature of 4 WC.

Statistical analysis

The variance analysis of the results, when applicable, was
made using SISVAR software (Ferreira ) and, when sig-

nificant, the Scott–Knott test, to 5% of probability, was
applied for comparison of the averages.

Obtention of the raw enzymatic extract

The fruits, roots and tubers of the vegetables were properly
washed in running water and distilled water. Soon after-

wards, 25 g of the peeled vegetable tissue was cut up and
homogenized in a blender with 100 mL of 0.05 mol L�1

phosphate buffer (pH 6.5) for 30 s. The homogenate was fil-

tered through organza cloth and centrifuged at 10,000g for
15 min, at 4 WC. The supernatant solution was stored at
4 WC and used as the enzymatic source of the peroxidase

(Fatibello-Filho & Vieira ). The peels and leaves of the
vegetables were washed in running water and distilled, cut
into small uniform pieces, and subjected to the same extrac-
tion procedure described previously.

The experimental design used was completely random-
ized with 15 treatments and three repetitions of three
vegetables.

Determination of the enzymatic activity

The activity was determined according to Khan & Robinson
(), using the following reaction medium: 1.5 mL guaia-
col (Vetec; 97%) 1% (v/v), 0.4 mL of H2O2 (Vetec, PA,

0.3% (v/v)), 0.1 mL enzyme (maintained in an ice bath)
and 1.2 mL of 0.05 mol L�1 phosphate buffer (pH 6.5).
The reaction was incubated for 5 min at 30 WC in a
Spectrovision spectrophotometer that was coupled to a

thermostatic bath.
One unit of peroxidase activity represents the oxidation

of 1 μmol of guaiacol in 1 min in the assay conditions, and

it was calculated using data relative to the linear portion
of the curve.

Influence of additives on the enzymatic activity

The additives NaCl (0.2 mol L�1), KCl (0.2 mol L�1), PEG
4000 (polyethylene glycol, 2% (p/v)), PVP (insoluble polyvi-

nylpyrrolidone, 2% (p/v)) and EDTA (10 mmol L�1) were
added separately into the extrator solution to evaluate
their influence on the enzymatic activity (Holschuh ).
The control was the activity in the absence of any additives.

The experimental design we adopted was completely
randomized with five treatments and three repetitions.

Influence of pH on enzymatic activity and
thermal stability

The optimum pH was determined by varying the pH of the
buffer solutions from 2.0 to 9.0 in intervals of one pH unit.
The buffers used were citrate buffer (0.1 mol L�1, pH 2.0
to 6.0) and Tris-HCl buffer (0.1 mol L�1, pH 7.0 to 9.0).

The experimental design that was adopted was comple-
tely randomized with eight treatments and three repetitions.

The thermal stability of the peroxidase was evaluated by

incubating the enzyme for 1, 2 and 4 h, and by varying the
temperature from 30 to 90 WC at intervals of 10 WC. After
the thermal treatment, the samples were cooled in an ice

bath, and the residual activity was determined. As a control,
the raw enzymatic extract activity without thermal treat-
ment was determined. Three repetitions for each treatment

were carried out.

Precipitation of proteins

Precipitation by acetone

Cold acetone was added to the raw enzymatic extract until it

reached a concentration of 65% (v/v). After incubating for
12 to 14 h, at �18 WC, the homogenate was centrifuged at
11,000g for 15 min at 4 WC. The supernatant was discarded.

The precipitate containing the peroxidase was submitted to
the removal of the acetone by evaporation in an ice bath
for 3 h. The precipitate was re-suspended in 10 mL of

sodium phosphate buffer (pH 6.5), and the resulting suspen-
sion was used for the determination of the enzymatic
activity. The procedure was repeated three times.

Precipitation by ammonium sulfate

The precipitation by ammonium sulfate was performed

according to literature precedent (Zeraik et al. ), with
some modifications. In the first stage, solid ammonium

Table 1 | Peroxidase activity of raw extracts from different plant tissues

Sample
Plant
tissues

Activity
(U mL�1)*

Activity (U g �1

plant tissue)

Zucchini squash
(Curcubita pepo)

Fruit 0.223 c 0.892
Peel 1.253 g 5.012
Leaves 0.845 e 3.380

Sweet potato (Ipomoea
potatoes (L.) Lam.)

Tuber 0.105 b 0.420
Peel 0.812 e 3.248
Leaves 0.316 d 1.264

Gilo (Solanum gilo
Raddi)

Fruit 0.275 d 1.100
Peel 0.159 c 0.636
Leaves 0.189 c 0.756

Turnip (Brassica
campestre ssp. rapifera)

Root 1.080 f 4.320
Peel 1.487 h 5.948
Leaves 0.024 a 0.096

Radish (Armoracia
rusticana)

Root 0.225 c 0.900
Peel 1.039 f 4.156

*Averages followed by the same letter in column do not differ among themselves by

Scott–Knott test at 5% probability.

672 M. C. Silva et al. | Obtention of peroxidase and its potential for decolorization Water Science & Technology | 65.4 | 2012

sulfate was added to the extract, so as to obtain a 40% satur-

ation. At this point, a clarification of the extract solution is
observed, originating from the precipitation of the cyto-
plasmic and nuclear materials and/or proteins present.

That solution was maintained at 4 WC for 20 h and centri-
fuged at 8,000g for 10 min, at 4 WC. The precipitate was
discarded, and more solid ammonium sulfate was added to
the supernatant to reach an 85% saturation. The solution

was maintained at 4 WC for an additional 20 h. The super-
natant was separated from the precipitate by centrifugation
at 8,000g for 10 min at 4 WC, and at this stage, the super-

natant was discarded, and the precipitate was re-
suspended in 5 mL of pH 6.5 sodium phosphate buffer.

The resulting suspension was dialyzed against a pH 6.5

sodium phosphate buffer for 24 h (32 mm benzoylated dialy-
sis tubing with a cutoff range of 2 kDa, five daily changes, in
a refrigerator and subjected to magnetic agitation) for the
removal of the ammonium sulfate. The resulting suspension

was submitted for enzymatic activity determination. The
procedure was conducted in triplicate.

Decolorization assays

Based on the methodology described by Khan & Robinson
() with modifications, the enzymatic oxidation reactions
of the textile dyes were conducted at 30 WC in 1.2 mL phos-
phate buffer (0.05 mol L�1, pH 7.0) containing 0.4 mL H2O2,

1.5 mL Remazol Turquoise G 133%, and 0.1 mL of enzymatic
solution. The final volume of reaction medium was 3.2 mL.
The H2O2, enzyme and dye concentrations at middle were

100 μmol L�1, 20.3 U mL�1 and 50 mg L�1, respectively.
The plant enzymatic extract that is considered most

appropriate for use in the oxidation of the dyes (which pre-

sents higher enzymatic activity) was treated with acetone to
induce precipitation as described, and used in the decolori-
zation assays.

The reaction mixture was incubated in a spectropho-
tometer that was coupled to a thermostatic bath, and the
absorbance of the dye was measured at different times during
the experiments. Monitoring of the oxidation was done at

624 nm, the maximum wavelength for Remazol Turquoise G
was 133%. The calculation to determine the percentage of
color removal of the dyeswas done according to the equation:

absorbancyinitial � absorbancyfinal
absorbancyinitial

× 100

To evaluate the dye adsorption by the enzymatic extract, the
reaction medium containing 1.6 mL phosphate buffer

(0.05 mol L�1 pH 7.0), 1.5 mL of the Remazol Turquoise G

133% dye (50 mg L�1) and 0.1 mL of the enzymatic extract
(12.18 U mL�1) was incubated in a spectrophotometer at
30 WC for 2 h and the dye removal was analyzed at 624 nm.

RESULTS AND DISCUSSION

Obtention of a vegetal source rich in peroxidase

Among the vegetable sources that were analyzed, the turnip
peel (Brassica campestre ssp. rapifera) provided higher enzy-
matic activity, while the turnip (Brassica campestre ssp.

rapifera) and radish leaves (Armoracia rusticana) presented
lower activity (Table 1). It was also observed that the turnip
root constitutes a rich peroxidase source; therefore, the

turnip was adopted (peel and root) as the main source of
the enzyme. All of the subsequent assays were conducted
using this enzymatic source.

Influence of additives on peroxidase activity

The influence of the additives on the peroxidase activity was
investigated. There was significant variation in the activity of

the peroxidase obtained from the turnip extract (PET) under
the influence of additives (Table 2). The extractor solution
containing NaCl (0.2 mol L�1) induced a higher increase
of the enzymatic activity, followed by KCl (0.2 mol L�1)

and EDTA (10 mmol L�1), while 2% (p/v) PEG and 2%
(p/v) PVP resulted in a decrease in the activity.

Table 2 | Influence of additives on the activity of peroxidase, obtained from the raw

extract of radish*

Additives
Activity
(U mL�1)*

Activity (U g�1 plant
tissue)

PEG (2%) 0.248 a 0.992

PVP (2%) 0.262 a 1.048

Control (without
additives)

0.330 b 1.320

EDTA (10 mmol L�1) 0.398 c 1.592

KCl (0.2 mol L�1) 0.473 d 1.892

NaCl (0.2 mol L�1) 0.776 e 3.104

*Averages followed by the same letter in the column do not differ among themselves by

Scott–Knott test at 5% probability.

Figure 1 | Effect of pH on peroxidase activity

obtained from the crude extract of turnip.

Figure 2 | Influence of temperature and incubation time on the stability of peroxidase

obtained from the crude extract of turnip.

673 M. C. Silva et al. | Obtention of peroxidase and its potential for decolorization Water Science & Technology | 65.4 | 2012

Several studies describe a significant improvement in the
activityand stabilityof enzymeswhen theextractionprocedure
is accomplished in the presence of additives. Additives have
been used for protection from enzyme inactivation, retention

of the water layer around the biocatalyst and as enzyme
molecule dispersers and mass transport facilitators. The inter-
actionof the additivewith the enzymecanpresent antagonistic

behavior; that is, the interaction can present a negative effect
in the reaction of interest, decreasing the efficiency of
enzyme, as was observed for the 2% (p/v) PEG and 2% (p/v)

PVP additives. Soares et al. () affirms that not all of the
additives are efficient stabilizers, and the influence of the addi-
tive on the enzymatic activity still has not been totally clarified.

Influence of pH on enzyme activity and thermal stability

The PET activity showed significant variation as a function

of the pH. PET presented high activity at pH 7.0 (Figure 1).
In acidic pH, the peroxidase presented an activity

decrease. This activity decrease might have occurred

mainly by ionic alterations of the enzyme that alter the
form of the enzyme and consequently the active site. The
activity decrease can also be observed at pH 9.

The pH for the maximum peroxidase activity varies
with the enzyme source, the isoenzyme composition, the
donor substrate, and the buffer used for the analysis

(Vámos-Vigyázó ).
pH values in the range of 5.7 to 5.9 were found for the

carom peroxidase, using guaiacol as the substrate (Holschuh
). The peroxidase of the leaves of Copaifera langsdorffii
(Diesel Tree) presented high activity in the pH range of 5.5
to 6.0 (Maciel et al. ).

The study of the effect of temperature on the PET stability

showed that the enzyme is thermostable up to 40 WC after 1, 2
and 4 h of incubation (Figure 2). At 50 WC, a small activity

decreasewas observed after 2 and 4 h of incubation. The enzy-

matic activitywas lost completely at temperatures above 70 WC.
The peroxidase stability is very important for its use in

various areas of the sciences. The higher the stability and

enzymatic activity, the better the enzyme application
capacity in diverse methods such as application as
biocatalysts (Maciel et al. ). According to the results
obtained in a temperature range of 30 to 50 WC, the resulting

enzyme did not present a significant decrease in the enzy-
matic activity, which favors its use in industrial processes.

Precipitation of the proteins

The most efficient precipitating agent was acetone, which led
to a 94.48± 0.62% recovery in terms of the enzyme activity,

while theammoniumsulfate gaveonly 64.85± 6.49%recovery
of activity. Besides providing high recovery, the precipitation

674 M. C. Silva et al. | Obtention of peroxidase and its potential for decolorization Water Science & Technology | 65.4 | 2012

with acetone does not require dialysis, thus reducing the dur-

ation and cost of the process, which yields the enzyme
through aneconomically simple and viable process. Therefore,
precipitationwith acetone to yield the enzymewas performed.

Figure 3 | Removal of the Remazol Turquoise G 133% dye catalyzed by the commercial

enzyme horseradish peroxidase (HPR) and by peroxidase of Brassica cam-

pestris ssp. rapifera (PET).

Decolorization of Remazol Turquoise G 133% enzymatic
dye catalyzed by horseradish peroxidase (HPR) and
turnip peroxidase

The Remazol Turquoise G 133% dye is widely used by tex-
tile industries. It belongs to the class of reactive dyes and

contains a monofunctional group and vinyl sulfone as the
reactive group.

The decolorization of the dye in aqueous solution
catalyzed by horseradish peroxidase (22 U mL�1) was 41%

after 50 min in the presence of the enzyme, while when
catalyzed by the peroxidase of Brassica campestre ssp.
rapifera (20.3 U mL�1), 56% of the dye was degraded

under the same assay conditions (Figure 3).
Similar results were found by Souza et al. () who

obtained59%ofRemazolTurquoiseG133%dyedecolorization

in aqueous solution with HPR under the following conditions:
a dye concentration of 100 mg mL�1, 29.85 U mL�1 of HPR,
2 μmol L�1 of H2O2 and a pH between 4.0 and 5.0 at 30 WC.

There was no adsorption of the dye by the enzymatic

extract because in the absence of hydrogen peroxide, there
was no dye reduction. This situation indicates that the deco-
lorization occurs exclusively as a function of the catalytic

activity of the enzyme.
Considering the kinetics of biodegradation of dye

Remazol Turquoise G 133% by turnip peroxidase and horse-

radish peroxidase enzymes, the pseudo-constant kinetics
were calculated for both enzymatic reactions, in accordance
with Barreto and coworkers ().

Data obtained (Table 3) suggested that both enzymatic
reactions (Table 1), follow a pseudo-second-order kinetics.
The results also showed that the reaction catalyzed by
turnip peroxidase presented the higher pseudo-constant kin-

etic when compared with horseradish peroxidase.

Table 3 | Kinetic parameters calculated for biodegradation of the Remazol Turquoise G 133%

Enzyme Pseudo-order

Turnip peroxidase (TP) Zero
Pseudo-first order
Pseudo-second order

Horseradish peroxidase (HRP) Zero
Pseudo-first order
Pseudo-second order

Similar results were found by Barreto and coworkers
(). The degradation of Procion Yellow and Procion Blue
dyes by Ganoderma sp. resulted in the following pseudo-

constant kinetics: 0.31 and 0.43 × 10�3 h�1, respectively.
The peroxidase of Brassica campestre ssp. rapifera turnip

peroxidase presented a degradation potential for this dye that

was superior to HPR without the need for purification. The
elimination of purification steps decreases the cost to obtain
the enzyme, enabling it to be used as an economically

viable alternative in the treatment of textile wastewaters.
Many treatments can be efficient in the decolorization,

but it is essential to know if there is formation of toxic

products during the process. Previous studies showed that
there was an increase in toxicity after enzymatic decoloriza-
tion of Remazol Turquoise G 133% by horseradish
peroxidase horseradish peroxidase (Forgiarini ). These

data suggest the formation of degradation products more
toxic than the parental molecule. The increased toxicity
may also be ascribed to the release of the Cu2þ ions of the

dye structure (Forgiarini ). Therefore, this fact shows
the importance of toxicological evaluation after enzymatic
treatment. In this case, when the metabolites formed are

dye by TP and HRP

Equation R2 K/10�3 h�1

y¼�15.957� 0.2805x 0.864 280.5
y¼�0.3697� 0.0103x 0.909 10.3
y¼ 0.0084þ 0.0004x 0.946 0.4

y¼�7.491� 0.2861x 0.964 286.1
y¼�0.1496� 0.0082x 0.9812 8.2
y¼ 0.0028þ 0.0002x 0.9928 0.2

675 M. C. Silva et al. | Obtention of peroxidase and its potential for decolorization Water Science & Technology | 65.4 | 2012

more toxic than the parent molecule, the enzymatic treat-

ment should be considered as pre-treatment.

CONCLUSIONS

The enzyme obtained presented optimum activity at pH 7.0

and proved thermally stable. The extraction solution contain-
ing NaCl 0.2 mol L�1 provided an increase in enzyme activity.

The turnip peroxidase was capable of removing up to

56% of the Remazol Turquoise G 133% dye in aqueous sol-
ution after 50 min of reaction. While the decolorization
obtained for horseradish peroxidase was 41% under the

same conditions.
The efficiency of turnip peroxidase in the oxidation of the

dye was comparable with horseradish peroxidase, a commer-

cial enzyme generally utilized in discoloration processes.

REFERENCES

Al-Ansari, M. M., Modaressi, K., Taylor, K. E., Bewtra, J. K. &
Biswas, N.  Soybean peroxidase-catalyzed oxidative
polymerization of phenols in coal-tar wastewater: comparison
of additives. Environmental Engineering Science 27, 967–975.

Barreto, W. J., Bernardino, N. D., Afonso, R. & Doi, S. M. O. 
Biodegradation of a mixture of textile dyes using the fungus
Ganoderma sp: a kinetic study. Química Nova 34, 568–572.

Bhunia, A., Durani, S. & Wangikar, P. P.  Horseradish
peroxidase catalyzed degradation of industrially important
dyes. Biotechnology and Bioengineering 72, 562–567.

Dec, J. & Bollag, J. M.  Use of plant material for the
descontamination of water polluted with phenols.
Biotechnology and Bioengineering 44, 1132–1139.

Diao, M., Ouédraogo, N., Baba-Moussa, L., Savadogo, P. W.,
N’Guessan, A. G., Bassolé, I. H. N. & Dicko, M. H. 
Biodepollution of wastewater containing phenolic
compounds from leather industry by plant peroxidases.
Biodegradation 22, 389–396.

Doonan, S.  Protein Purification Protocols, vol. 59, 405 pp.
Humana Press, Towota.

Fatibello-Filho, O. & Vieira, I. C.  Analytical use of raw
extract from vegetables tissue such as enzyme source.
Química Nova 25, 455–464.

Ferreira, D. F.  Statistical analysis through Sisvar (System for
analysis of variance) for Windows 4.0. In:Annual Meeting of
Regionof theBrazilianSociety InternationalBiometrics, 45. São
Carlos. Abstracts São Carlos: UFSCar, 2000. pp. 255–258.

Ferreira, D. F.  SISVAR: version 4.6 (build 6.1) software.
Lavras: DEX/UFLA. Available from: http://www.dex.ufla.
br/danielff/dff02.htm (accessed 15 Dec 2010).

Ferreira-Leitao, V. S., da Silva, J. G. & Bon, E. P. S. Methylene
blue and azure B oxidation by horseradish peroxidase: a
comparative 19 evaluation of class II and class III peroxidases.
Applied 443 Catalysis B444 Environmental 42, 213–221.

Forgiarini, E.  Degradation of Dyes and Textile Wastewaters
by Horseradish Peroxidase (HPR) Enzyme. Master Thesis,
Federal University of Santa Catarina, Brazil.

Guarantini, C. C. I. & Zanoni, M. V.  Textile dyes. Química
Nova 23, 71–75.

Hiner, A. N. P., Hernandez-Ruiz, J., Williams, G. A., Arnao, M. B.,
Garcia-Canovas, F. & Acosta, M.  Catalase-like oxygen
production by horseradish peroxidase must predominantly
be an enzyme-catalyzed reaction. Archives of Biochemistry
and Biophysics 392, 295–302.

Holschuh, H. J.  Isolation, Purification and Biochemical
CharacterizationofPeroxidaseCarambola (Averrhoacarambola,
L.). PhD Thesis, State University of Campinas, Brazil.

Khan, A. A. & Robinson, D. S.  Hydrogen donor specifcity of
mango isoperoxidases. Food Chemistry 49, 407–410.

Li, H., Li, Y., Cao, H., Li, X. & Zhang, Y.  Degradation of
pentachlorophenol by a novel peroxidase-catalyzed process
in the presence of reduced nicotinamide adenine
dinucleotide. Chemosphere 83, 124–30.

Maciel, H. P. F., Gouvêa, C. M. C. P. & Pastore, G. M. 
Obtention of a new source of peroxidase from Copaífera
langsdorffii Desf. with high activity. Ciência e Tecnologia de
Alimentos 26, 735–739.

Maciel, H. P. F. G., Gouvêa, C. M. C. P. & Pastore, G. M. 
Extraction and partial characterization of peroxidase from
Copaifera langsdorffii Desf. Leaves. Ciência e Tecnologia de
Alimentos 27, 221–225.

Meizler, A., Roddick, F. & Porter, N.  A novel glass support for
the immobilization and UV-activation of horseradish
peroxidase for treatment of halogenated phenols. Chemical
Engineering Journal 172, 792–798.

Mohan, S. V., Prasad, K. K., Rao, N. C. & Sarma, P. N.  Acid azo
dyedegradationby free and immobilizedhorseradishperoxidase
(HRP) catalyzed process. Chemosphere 58, 1097–1105.

Soares, C. M. F., Santana, M. H. A., Zanin, G. M. & Castro, H. F.
 Effect of poly(ethylene) glycol and albumin on the
immobilization of microbial lipase and catalysis and catalysis
in organic media. Química Nova 26, 832–838.

Souza, S., Forgiarini, E. & de Souza, A. A. U.  Toxicity of textile
dyesand theirdegradationby theenzymehorseradishperoxidase
(HRP). Journal of Hazardous Materials 147, 1073–1078.

Vámos-Vigyázó, L. Polyphenol oxidase and peroxidase in fruits
and vegetables. Food Science and Nutrition 15, 49–127.

Veitch, N. C.  Horseradish peroxidase: a modern view of a
classic enzyme. Phytochemistry 65, 249–259.

Zanoni, M. V. & Carneiro, P. A.  Disposal of dyes. Ciência
Hoje 29, 61–64.

Zeraik, A. E., de Souza, F. S., Fatibello, O. & Leite, O. D. 
Development of a spot test for peroxidase activity
monitoring during a purification procedure. Química Nova
31, 731–734.

First received 30 June 2011; accepted in revised form 3 October 2011

http://dx.doi.org/10.1089/ees.2010.0143

http://dx.doi.org/10.1089/ees.2010.0143

http://dx.doi.org/10.1089/ees.2010.0143

http://dx.doi.org/10.1002/1097-0290(20010305)72:5%3C562::AID-BIT1020%3E3.0.CO;2-S

http://dx.doi.org/10.1002/1097-0290(20010305)72:5%3C562::AID-BIT1020%3E3.0.CO;2-S

http://dx.doi.org/10.1002/1097-0290(20010305)72:5%3C562::AID-BIT1020%3E3.0.CO;2-S

http://dx.doi.org/10.1002/bit.260440915

http://dx.doi.org/10.1002/bit.260440915

http://dx.doi.org/10.1007/s10532-010-9410-8

http://dx.doi.org/10.1007/s10532-010-9410-8

http://dx.doi.org/10.1590/S0100-40422002000300019

http://dx.doi.org/10.1590/S0100-40422002000300019

http://www.dex.ufla.br/danielff/dff02.htm

http://www.dex.ufla.br/danielff/dff02.htm

http://dx.doi.org/10.1016/S0926-3373(02)00238-2

http://dx.doi.org/10.1016/S0926-3373(02)00238-2

http://dx.doi.org/10.1016/S0926-3373(02)00238-2

http://dx.doi.org/10.1590/S0100-40422000000100013

http://dx.doi.org/10.1006/abbi.2001.2460

http://dx.doi.org/10.1006/abbi.2001.2460

http://dx.doi.org/10.1006/abbi.2001.2460

http://dx.doi.org/10.1016/0308-8146(94)90013-2

http://dx.doi.org/10.1016/0308-8146(94)90013-2

http://dx.doi.org/10.1016/j.chemosphere.2011.01.014

http://dx.doi.org/10.1016/j.chemosphere.2011.01.014

http://dx.doi.org/10.1016/j.chemosphere.2011.01.014

http://dx.doi.org/10.1016/j.chemosphere.2011.01.014

http://dx.doi.org/10.1590/S0101-20612006000400003

http://dx.doi.org/10.1590/S0101-20612006000400003

http://dx.doi.org/10.1590/S0101-20612007000200002

http://dx.doi.org/10.1590/S0101-20612007000200002

http://dx.doi.org/10.1016/j.cej.2011.06.065

http://dx.doi.org/10.1016/j.cej.2011.06.065

http://dx.doi.org/10.1016/j.cej.2011.06.065

http://dx.doi.org/10.1016/j.chemosphere.2004.09.070

http://dx.doi.org/10.1016/j.chemosphere.2004.09.070

http://dx.doi.org/10.1016/j.chemosphere.2004.09.070

http://dx.doi.org/10.1590/S0100-40422003000600010

http://dx.doi.org/10.1590/S0100-40422003000600010

http://dx.doi.org/10.1590/S0100-40422003000600010

http://dx.doi.org/10.1016/j.jhazmat.2007.06.003

http://dx.doi.org/10.1016/j.jhazmat.2007.06.003

http://dx.doi.org/10.1016/j.jhazmat.2007.06.003

http://dx.doi.org/10.1016/j.phytochem.2003.10.022

http://dx.doi.org/10.1016/j.phytochem.2003.10.022

http://dx.doi.org/10.1590/S0100-40422008000400003

http://dx.doi.org/10.1590/S0100-40422008000400003

Reproduced with permission of copyright owner.
Further reproduction prohibited without permission.

  • Obtention of plant peroxidase and its potential for the decolorization of the reactive dye Remazol Turquoise G 133%
  • INTRODUCTION

    METHODS

    Vegetables, commercial enzyme and dye

    Statistical analysis

    Obtention of the raw enzymatic extract

    Determination of the enzymatic activity

    Influence of additives on the enzymatic activity

    Influence of pH on enzymatic activity and thermal stability

    Precipitation of proteins

    Precipitation by acetone

    Precipitation by ammonium sulfate

    Decolorization assays

    RESULTS AND DISCUSSION

    Obtention of a vegetal source rich in peroxidase

    Influence of additives on peroxidase activity

    Influence of pH on enzyme activity and thermal stability

    Precipitation of the proteins

    Decolorization of Remazol Turquoise G 133% enzymatic dye catalyzed by horseradish peroxidase (HPR) and turnip peroxidase

    CONCLUSIONS

    REFERENCES

Hoffman
Biology 1406 Lab

1

Lab Team Number: 2 Date: 10/13/202

4

Team Members: Robert, Jay, Nesna, Nadia

Experimental Plan

1. After gathering and reading information about the topic, write down some questions or observations

that have surfaced.

Could the varied pH have a drastic effect on the absorbance even at a single increase of active acidity or
alkaline base? At which pH could I record the least reaction to the bases control? Could some of the
materials peroxidase concentration differ at a difference of sq/ft for each subject? What is the peroxidase
concentration differ between sub species of cabbages and turnips?

2. Explain the purpose for standardizing the plant extract containing peroxidase (see the experiment).

We would be creating a standardized batch of the extract containing consistent concentration of
peroxidase. It is important to have, to ensure reliable comparisons along with all the solutions used in the
experiment. I will also help to determine the constant reactions of the peroxidase activity overtime and
under varied pH conditions.

3. Write a null Ho and alternative Ha hypothesis for the affect of pH (see the experiment).

Null: The pH would have no significate effect on the activity and stability of the absorbance of the
peroxidase, with no optimal pH range for activity or stability.
Alternate: The pH significantly affects the activity and the stability of the cabbage and turnip
peroxidase with a promising pH range for the peroxidase with the dye interaction changing the
absorbance to 1 with minor margins from the literature.

Hoffman
Biology 1406 Lab

2

4. From the affect of pH hypotheses: write a prediction for each plant tested (total of two). Predictions

must be about a specific pH your group will test or pH range. Do not make predictions about an

optimal pH or pH range.

Turnip: At a pH 6.0, peroxidase may present a decrease in the activity compared to the literature that was
at pH 5.7, showing that it is less effective in a slightly acidic condition.
Cabbage: At a pH 4.0 the cabbage peroxidase would retain substantial level of absorbance, through
slightly lower than the optimal pH if 5.5, showing that it remains relatively active in the mildly acidic
conditions.

5. Based on your team’s primary source findings, list the positive control pH buffer level your group will

use for each plant tested. When a decimal value is used (pH 5.5), round it.

  • Plant Positive Control pH buffer level
  • Turnip pH 6.0

    Cabbage pH 4.0

    6. As support, list in the same order, citations from the selected primary sources (APA format).

    Silva, M. C., Torres, J. A., Corrêa, A. D., Junqueira, A. M. B., Amorim, M. T. P., & dos Santos, C. D. (2012).
    Obtention of plant peroxidase and its potential for the decolorization of the reactive dye Remazol
    Turquoise G 133. Water Science and Technology, 65(4), 669–675. https://doi.org/10.2166/wst.2012.892

    Joel, E. B., Mafulul, S. G., Adamu, H. E., Goje, L. J., Tijjani, H., Igunnu, A., & Malomo, S. O. (2020).
    Peroxidase from waste cabbage (Brassica oleracea capitata L.) exhibits the potential to biodegrade phenol
    and synthetic dyes from wastewater. Scientific African, 10, e00608-.
    https://doi.org/10.1016/j.sciaf.2020.e00608

    7. Explain why the positive control pH buffer level provides an environment for an optimal peroxidase

    reaction rate. In other words, explain how the positive control pH buffer affects peroxidase folding and

    the shape of the active site.

    The positive control pH buffer level is important for providing a prime environment of peroxidase activity

    because of its effect on enzyme structure, mainly the folding and general shape of the active site. When

    the enzyme is correctly folded while the active site is correctly shaped the reaction rate should increase.

    A change in the pH level can change the chemical environment which is why positive control pH buffer

    affects the shape and active folding.

    Hoffman
    Biology 1406 Lab

    3

    8. List the experimental pH buffer levels for each plant tested. List them in the same order as in

    statement five. Remember, the positive control pH level has been identified for each experiment.

  • Plant Experimental pH Buffer Levels
  • Turnip pH 7.0
    Cabbage pH 5.5

    9. Explain why the experimental pH levels may not provide an environment that is optimal for

    peroxidase reactions. As it relates to acidic and basic environments, use the terms protonation,

    deprotonation and denaturing. In other words, explain how the experimental pH buffer levels affect

    peroxidase folding and the shape of its active site.

    If the conditions are acidic, having extra hydrogen ions can lead to protonation of some amino acid side
    chains. The changes or alterations could disrupt the ionic interactions that maintain the 3-D structure of
    the enzyme.
    When incorrectly protonation occurs the protein signals can destabilize, resulting in denaturing. While the
    proteins unfold in changes the active site shape, it can reduce the ability of the enzyme to bind to the
    substrate and catalyze a reaction.
    If the conditions are at a higher pH a protonated amino side chain can go through deprotonation. The
    change can effect the general charge distribution, basically disrupting the Hydrogen bonds and ionic
    interactions that stabilize the folded shape. Deprotonation can lead to misconfiguration of the active site,
    which could lead to the active site not being suitable for substrate binding.

    10. State the independent and dependent variables of the experiment.

    The independent variable is the time measured for the experiment.

    The dependent variable is the absorbance of the solution recorded from the experiment.

    Hoffman
    Biology 1406 Lab

    4

    11. Qualitatively, explain how the rate of the peroxidase reaction will be measured. Include an

    explanation of the chemical reaction.

    The rate of the reaction can be measured by monitoring the absorbance of the solution at 470nm using
    the spectrophotometer, then recording the concentration and color change that increases in relation to
    the absorbance vs time. The ideal readings for the experiment would be a 1 absorbance at the end of the
    2-minute mark. We are interested in the chemical reaction of the hydrogen peroxide buffer with the
    peroxidase and the final oxidated product.

    H2O2 + Guaiacol Dye + Peroxidase → 2H2O + Guaiacol Dye + Peroxidase (oxidized)

    12. Quantitatively, explain how the rate of the peroxidase reaction will be measured.
    We will prepare all reaction mixture to their proper solutions mixture variants. We will start by recording
    the control first then record the changes of absorbance in the spectrophotometer at 470nm every 20 secs
    for a 2-minute span for each solution. Once the experiment is complete, we will calculate the rate of the
    reactions by determining absorbance overtime. A line graph will be used to find the slope of the
    absorbance vs time.

    13. List the four parts of the experiment in chronological order.

    1. Create the extract
    2. Standardize the extract
    3. Test the effect of the pH on extract
    4. Graph – analyze

    • Lab Team Number: 2 Date: 10/13/2024
    • Plant Positive Control pH buffer level

      Plant Experimental pH Buffer Levels

    Expert paper writers are just a few clicks away

    Place an order in 3 easy steps. Takes less than 5 mins.

    Calculate the price of your order

    You will get a personal manager and a discount.
    We'll send you the first draft for approval by at
    Total price:
    $0.00