Studies on isolation characterization and immobilization of a carboxyl esterase from Aeromonascaviae mtcc 7725

Abstract

The current work is focused on the purification and immobilization of a carboxyl esterase from Aeromonascaviae (MTCC7725). The culture was grown under submerged conditions. The conditions were optimized to enhance the production of esterase. It was found that after 12 hours of incubation, the esterase production was the highest. The culture was incubated at 37°C, pH7 and at 120 rpm in Luria bertani broth. The actively growing culture was plated on tributyrin supplemented agar plate. A clear zone of hydrolysis confirmed that the organism secretes esterase enzyme extracellularly. The protein was purified by ammonium sulphate precipitation and anion exchange chromatography. The protein precipitated with 70% ammonium sulphate solution showed maximum esterase activity. The protein was concentrated using polyethylene glycol and subjected to DEAE anion exchange chromatography. The molecular weight of the purified esterase was found to be 120 kDa by SDS PAGE. The activity of the purified protein was also confirmed by zymography. newline