Remediation of model wastewater polluted with methyl parathion by reverse micelle entrapped peroxidase

The peroxidase/reverse micelle (RM) system effectively catalyzed the oxidation reaction in cyclohexane, while peroxidase from bitter gourd in aqueous buffer exhibited low catalytic activity. The oxidation of methyl parathion (MPT) has been optimized with effects of pH in the water pools, concentration of peroxidase and degree of surfactant hydration (Wo). The peroxidase/RM system showed a strong pH dependency. Its optimum catalytic activity was obtained when the peroxidase/ RM was prepared in a buffer of pH 3.0. The effect of different redox mediators on the peroxidasecatalyzed oxidation of MPT was investigated. MPT was slowly oxidized by the peroxidase/RM system while the addition of phenol as a redox mediator strongly enhanced the catalytic performance of the peroxidase/RM system. Hydrogen peroxide strongly inhibited the activity of peroxidase; when the H2O2 was present at more than 0.80 mM, the MPT transformation was significantly reduced. doi: 10.2166/wqrjc.2012.020 Zoheb Karim Rohana Adnan School of Chemical Sciences, Universiti Sains Malaysia, 11800 Minden, Penang, Malaysia Qayyum Husain (corresponding author) Faculty of Applied Medical Science, Jazan University, Jazan, Post Box 2092, Kingdom of Saudi Arabia E-mails: qayyumhusain@yahoo.co.in; qayyumbiochem@gmail.com Naseem Akhtar Department of Biosciences, Jamia Millia Islamia, Jamia Nagar, New Delhi-110025, India