Properties of hydrogel-entrapped lipase of thermophilic <i style="">Pseudomonas aeruginosa</i> BTS-2

Abstract

<i style="">Pseudomonas aeruginosa</i> BTS-2 produced lipase (total yield, 55.4 U/L) optimally on a mineral based (MB) broth, supplemented with 1% (v/v) cottonseed oil as sole carbon source, after incubation at 56°C for 48 h. The presence of 4% (w/v) yeast extract in the MB broth further increased the lipase production by ~ 3-folds. The purified lipase was efficiently (~80%) immobilized in alginate than carrageenan beads. The alginate-immobilized lipase (beads) showed optima at <i style="">p</i>H 7.5 and 55°C temperature. An increase in C-chain of alcohols increased the activity of entraped lipase. Exposure of alginate beads to decyl (C:10) and dodecyl (C:12) alcohol enhanced the lipase activity by 47 and 64%, respectively. Whereas, most alkanes decreased the activity of immobilized lipase but exposure to nonane enhanced the activity by 52%. The lipase efficiently esterified ethanol and acetic acid to ethyl acetate.