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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
Dye decolourization as a function of pH.
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fig9: Dye decolourization as a function of pH.

Mentions: Effect of pH on the decolourization of the dyes was monitored at a pH range of 3.5–10.0. The highest percentage decolourization was observed at pH 4.5 for all the dyes used at 85, 86, 45, and 92% for Vat Yellow 2, Vat Orange 11, Vat Green 9, and Vat Black 27, respectively (Figure 9). At pH 5 and pH 5.5, the decrease in percentage decolourization percentage was not very significant (P > 0.05). A significant decrease (P < 0.05) was noticed from pH of 6.5 down to the alkaline pH as shown in Figure 9. Vasantha et al. [29] reported the best decolourization of Direct Yellow 12 using horseradish peroxidase at pH of 4.0. Husain et al. [28] observed 68% decolourization of industrial effluent dyes at pH 5.0 using peroxidase from fenugreek. Literature has shown that the highest/best percentage decolourization of various synthetic dyes occurs within pH 4–6.0. The result of this investigation which shows a pH of 4.5 as the best pH for the decolourization of the various dyes under study is in agreement with literature.


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

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

Dye decolourization as a function of pH.
© Copyright Policy - open-access
Related In: Results  -  Collection

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

fig9: Dye decolourization as a function of pH.
Mentions: Effect of pH on the decolourization of the dyes was monitored at a pH range of 3.5–10.0. The highest percentage decolourization was observed at pH 4.5 for all the dyes used at 85, 86, 45, and 92% for Vat Yellow 2, Vat Orange 11, Vat Green 9, and Vat Black 27, respectively (Figure 9). At pH 5 and pH 5.5, the decrease in percentage decolourization percentage was not very significant (P > 0.05). A significant decrease (P < 0.05) was noticed from pH of 6.5 down to the alkaline pH as shown in Figure 9. Vasantha et al. [29] reported the best decolourization of Direct Yellow 12 using horseradish peroxidase at pH of 4.0. Husain et al. [28] observed 68% decolourization of industrial effluent dyes at pH 5.0 using peroxidase from fenugreek. Literature has shown that the highest/best percentage decolourization of various synthetic dyes occurs within pH 4–6.0. The result of this investigation which shows a pH of 4.5 as the best pH for the decolourization of the various dyes under study is in agreement with literature.

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