10.22376/ijpbs.2019.10.1.p1-12 Volume 4 Issue 3 2013 (July - September) Covalent immobilization of peroxidase is convenient in continuous processes to improve them economically. In the present study, peroxidases from lessThan i greaterThan Sapindus mukorossi lessThan /i greaterThan were immobilized and used for removal of 4-chlorophenol (4-CP) by the polymerization pathway. Five milligram of vacuum dried polyaniline-glutaraldehyde composite was incubated in 1ml sodium acetate buffer (50mM;pH 5.0) containing 0.5 mg/ml of peroxidase, at 4°C, and the mixture was maintained under orbital agitation. When free and immobilized peroxidases were tested for their ability to remove 4-CP from aqueous solution, temperature and pH optima for both was recorded at 40°C and 5.0 respectively. K lessThan sub greaterThan m lessThan /sub greaterThan and V lessThan sub greaterThan max lessThan /sub greaterThan with respect to H lessThan sub greaterThan 2 lessThan /sub greaterThan O lessThan sub greaterThan 2 lessThan /sub greaterThan were calculated to be 0.44mM and 134.7 E.U and with respect to guaiacol were determined to be 3.5mM and 70.54 E.U. respectively.The removal of 4-CP was maximum when the immobilized enzymes were incubated in a batch reaction for 90 minutes. The percentage removal of 4-CP (0.2mM solution) was reported to be 100, 50, 26, 0 in the 1 lessThan sup greaterThan st lessThan /sup greaterThan , 2 lessThan sup greaterThan nd lessThan /sup greaterThan , 3 lessThan sup greaterThan rd lessThan /sup greaterThan , 4 lessThan sup greaterThan th lessThan /sup greaterThan cycle respectively in the batch reaction. JAGTAR SINGH AND ATIN SHARMA Sapindus mukorossi, Covalent immobilization, Polyaniline-glutaraldehyde (PAniG), Sapindus peroxidase, 4-Chlorophenol (4-CP) 171-180