Entrapment of lipase in polymer of polyvinyl alcohol-boric acid for esterification in organic media

Abstract

Polyvinyl alcohol (PVA)-boric acid method has been utilized for entrapment of <i style="">Candida rugosa </i>lipase. Immobilized lipase was used to produce ethyl butyrate, a flavour ester showing 80.2% conversion in 72 h. Lipase in PVA-boric acid beads possessed the ability to synthesize variety of esters and was stable in various organic solvents with varying log P value from 2 to 8 under incubation at 50°C for 1 h.The immobilized lipase showed nearly full retention of activity even after 8 cycles of use, the activity then gradually decreased reaching to 56% conversion efficiency after 20 cycles and possesses a shelf-life of 10 months. The thermostability of the lipase increased three times upon immobilization. The immobilized enzyme possessed 40% higher activity compared to its free counterpart.