Immobilization of sorghum leaf oxalate oxidase onto alkylamine and arylamine glass

Abstract

An oxalate oxidase (EC 1.2.3.4) purified from grain sorghum leaves was immobilized onto alkylamine and arylamine glass beads through glutaraldehyde coupling and diazotization with a conjugation yield of 10.8 mg/g support and 9.2 mg/g support, respectively. The enzyme retained 67.5% and 34.1% of its initial specific activity after immobilization onto alkylamine and arylamine glass, respectively. The enzyme exhibited an increase in optimum pH, temperature for maximum activity, energy of activation (Ea) and time for linearity but decrease in thermal stability at 60 degrees C after immobilization on both types of beads. The K(m) value for oxalate was increased by 9- to 10-fold but Vmax remained unaltered after immobilization. Both alkyl and arylamine glass bound enzyme was unaffected by physiological concentrations of Cl- and NO3-. The analytic importance of this work is demonstrated.