title: Application of fly ash adsorbed peroxidase for the removal of bisphenol A in batch process and continuous reactor: assessment of genotoxicity of its product.
abstract: In the present study peroxidase has been immobilized simply by adsorption on fly ash. On fly ash adsorbed nearly 1113 U of peroxidase activity per g. Comparative degradation of endocrine disrupter, bisphenol A has been performed by soluble and immobilized enzyme. Soluble and immobilized enzyme removed maximum bisphenol A in the presence of 0.3mM guaiacol, a redox mediator, 0.75 mM H(2)O(2) in sodium phosphate buffer, pH 7.0 at 40 °C. Degradation of bisphenol A in batch process was 61%, 100% and 100% at 20, 40 and 60 °C, respectively. Fly ash adsorbed peroxidase was more effective in the degradation of bisphenol A as compared to its free form. Immobilized enzyme catalyzed complete degradation of bisphenol A at 40 °C within 3.5h. The oxidative degradation and polymerization of bisphenol A was also evaluated in the continuous bed-reactors at different flow rates. The removal of this compound was maximum at a flow rate of 20 mL h(-1). HPLC analysis showed two clear peaks, one related to bisphenol A and other related to its degradation product, 4-isopropenylphenol. Plasmid nicking and comet assays demonstrated that the product, 4-isopropenylphenol was significantly nontoxic.
authors.affiliation: Department of Biochemistry, Faculty of Life Sciences, Aligarh Muslim University, Aligarh, India.
authors.forename: Zoheb
authors.initials: Z
authors.lastname: Karim
authors.forename: Qayyum
authors.initials: Q
authors.lastname: Husain
mesh_terms: D000645:Ammonium Sulfate; D001559:Benzhydryl Compounds; D002244:Carbon / Q000737:chemistry*; D002384:Catalysis; D002851:Chromatography, High Pressure Liquid; D060729:Coal Ash; D020552:Comet Assay; D004247:DNA / Q000187:drug effects / Q000235:genetics; D004249:DNA Damage; D052244:Endocrine Disruptors / Q000302:isolation & purification*; D004800:Enzymes, Immobilized / Q000737:chemistry; D007202:Indicators and Reagents; D008214:Lymphocytes / Q000187:drug effects / Q000378:metabolism; D029777:Momordica charantia / Q000201:enzymology; D010084:Oxidation-Reduction; D052638:Particulate Matter / Q000737:chemistry*; D009195:Peroxidase / Q000737:chemistry*; D010636:Phenols / Q000302:isolation & purification / Q000627:therapeutic use* / Q000633:toxicity; D010957:Plasmids / Q000235:genetics; D000098826:Bisphenol A Compounds
chemical_list: D000645:Ammonium Sulfate; D001559:Benzhydryl Compounds; D002244:Carbon; D060729:Coal Ash; D004247:DNA; D052244:Endocrine Disruptors; D004800:Enzymes, Immobilized; D007202:Indicators and Reagents; D052638:Particulate Matter; D009195:Peroxidase; D010636:Phenols; C006780:bisphenol A; D000098826:Bisphenol A Compounds