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Biobleaching of industrial important dyes with peroxidase partially purified from garlic.

Osuji AC, Eze SO, Osayi EE, Chilaka FC - ScientificWorldJournal (2014)

Bottom Line: The Km and V max for H2O2 and o-dianisidine were 0.026 mM and 0.8 U/min, and 25 mM and 0.75 U/min, respectively.Peroxidase from garlic was effective in decolourizing Vat Yellow 2, Vat Orange 11, and Vat Black 27 better than Vat Green 9 dye.For all the parameters monitored, the decolourization was more effective at a pH range, temperature, H2O2 concentration, and enzyme concentration of 4.5-5.0, 50°C, 0.6 mM, and 0.20 U/mL, respectively.

View Article: PubMed Central - PubMed

Affiliation: Department of Biochemistry, University of Nigeria, Nsukka, Nigeria.

ABSTRACT
An acidic peroxidase was extracted from garlic (Allium sativum) and was partially purified threefold by ammonium sulphate precipitation, dialysis, and gel filtration chromatography using sephadex G-200. The specific activity of the enzyme increased from 4.89 U/mg after ammonium sulphate precipitation to 25.26 U/mg after gel filtration chromatography. The optimum temperature and pH of the enzyme were 50°C and 5.0, respectively. The Km and V max for H2O2 and o-dianisidine were 0.026 mM and 0.8 U/min, and 25 mM and 0.75 U/min, respectively. Peroxidase from garlic was effective in decolourizing Vat Yellow 2, Vat Orange 11, and Vat Black 27 better than Vat Green 9 dye. For all the parameters monitored, the decolourization was more effective at a pH range, temperature, H2O2 concentration, and enzyme concentration of 4.5-5.0, 50°C, 0.6 mM, and 0.20 U/mL, respectively. The observed properties of the enzyme together with its low cost of extraction (from local sources) show the potential of this enzyme for practical application in industrial wastewater treatment especially with hydrogen peroxide. These Vat dyes also exhibited potentials of acting as peroxidase inhibitors at alkaline pH range.

Show MeSH
Effect of pH on peroxidase activity.
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fig2: Effect of pH on peroxidase activity.

Mentions: From the pH studies, as the pH was increased, from pH 3.5 to pH 5.0, the peroxidase activity was found to increase. Further increase in pH resulted in a decrease of peroxidase activity (Figure 2). Peroxidase activity was found to be pH-dependent with inactivation observed within the alkaline pHs. Mizobutsi et al. [19] reported pH optimum of 6.5 for peroxidase from Litchi fruit. Mohapatra [4] reported an optimum pH of 4.0 for peroxidases from S. bicolor using guiacol as the substrate. Haq et al. [20] also reported an optimum peroxidase activity at pH 4.0 from Raphanus sativus. The result of this study is consistent with the findings of Marzouki et al. [21] who reported an optimum pH of 5.0 for peroxidase from Allium sativum. It is also comparable with the pH optimum of 5.0 reported by Kim and Lee [22] for peroxidase from sunflower. Garlic peroxidase was also found to be stable between pH 4.0 and 6.0 (Figure 3).


Biobleaching of industrial important dyes with peroxidase partially purified from garlic.

Osuji AC, Eze SO, Osayi EE, Chilaka FC - ScientificWorldJournal (2014)

Effect of pH on peroxidase activity.
© Copyright Policy - open-access
Related In: Results  -  Collection

Show All Figures
getmorefigures.php?uid=PMC4226186&req=5

fig2: Effect of pH on peroxidase activity.
Mentions: From the pH studies, as the pH was increased, from pH 3.5 to pH 5.0, the peroxidase activity was found to increase. Further increase in pH resulted in a decrease of peroxidase activity (Figure 2). Peroxidase activity was found to be pH-dependent with inactivation observed within the alkaline pHs. Mizobutsi et al. [19] reported pH optimum of 6.5 for peroxidase from Litchi fruit. Mohapatra [4] reported an optimum pH of 4.0 for peroxidases from S. bicolor using guiacol as the substrate. Haq et al. [20] also reported an optimum peroxidase activity at pH 4.0 from Raphanus sativus. The result of this study is consistent with the findings of Marzouki et al. [21] who reported an optimum pH of 5.0 for peroxidase from Allium sativum. It is also comparable with the pH optimum of 5.0 reported by Kim and Lee [22] for peroxidase from sunflower. Garlic peroxidase was also found to be stable between pH 4.0 and 6.0 (Figure 3).

Bottom Line: The Km and V max for H2O2 and o-dianisidine were 0.026 mM and 0.8 U/min, and 25 mM and 0.75 U/min, respectively.Peroxidase from garlic was effective in decolourizing Vat Yellow 2, Vat Orange 11, and Vat Black 27 better than Vat Green 9 dye.For all the parameters monitored, the decolourization was more effective at a pH range, temperature, H2O2 concentration, and enzyme concentration of 4.5-5.0, 50°C, 0.6 mM, and 0.20 U/mL, respectively.

View Article: PubMed Central - PubMed

Affiliation: Department of Biochemistry, University of Nigeria, Nsukka, Nigeria.

ABSTRACT
An acidic peroxidase was extracted from garlic (Allium sativum) and was partially purified threefold by ammonium sulphate precipitation, dialysis, and gel filtration chromatography using sephadex G-200. The specific activity of the enzyme increased from 4.89 U/mg after ammonium sulphate precipitation to 25.26 U/mg after gel filtration chromatography. The optimum temperature and pH of the enzyme were 50°C and 5.0, respectively. The Km and V max for H2O2 and o-dianisidine were 0.026 mM and 0.8 U/min, and 25 mM and 0.75 U/min, respectively. Peroxidase from garlic was effective in decolourizing Vat Yellow 2, Vat Orange 11, and Vat Black 27 better than Vat Green 9 dye. For all the parameters monitored, the decolourization was more effective at a pH range, temperature, H2O2 concentration, and enzyme concentration of 4.5-5.0, 50°C, 0.6 mM, and 0.20 U/mL, respectively. The observed properties of the enzyme together with its low cost of extraction (from local sources) show the potential of this enzyme for practical application in industrial wastewater treatment especially with hydrogen peroxide. These Vat dyes also exhibited potentials of acting as peroxidase inhibitors at alkaline pH range.

Show MeSH