Thermostable acidic lipase of Bacillus glycinifermentans-MK840989 isolated from contaminated environment; its optimization, purification and exploring potential applications

Abstract

This study is the first report about isolation, purification and optimization of lipase from Bacillus glycinifermentans. In this study, Bacillus glycinifermentansMK-840989 was isolated from a local petrol pump. The bacterium showed lipolytic zones of 0.19cm, 0.044cm, and 0.28cm on peptone yeast agar, olive oil hydrolysis agar and chromogenic plate agar, respectively. B. glycinifermentans also produced an extracellular lipase (55.1µmol/ml). This bacterium preferred acidic environment (pH 5) for growing optimally at 80˚C when the medium was supplemented with 1% olive oil. The olive oil induced its growth up to 9h. The protein content of the purified lipase was estimated about 75mg/ml as compared to its crude form, i.e. 350mg/ml. The purified lipase was found to be thermostable acidic in nature as its optimum activity was observed at 90˚C (0.08U/ml) and pH 5 (0.02U/ml). Other optimization factors included 1% olive oil (0.065U/ml), 0.1mM maltose (0.023U/ml), 0.1mM Ca (0.025U/ml), 1% yeast extract (16.8U/ml), 1% wheat waste (0.019U/ml), 1% commercial detergent (0.016U/ml) and 1% tween-20 (0.015 U/ml). The purified lipase showed a polypeptide of 26.7kDa on SDS-PAGE. These features such as thermostability, acidic nature, ability to show activity in wheat waste and tolerance to detergents render the lipase of B.glycinifermentans MK-840989 as an attractive choice for biotechnologists to employ it at industrial level. The purified lipase of B.glycinifermentans MK-840989 can be a potential candidate for detergent and oil-remediation industry. It can help to replace conventional synthetic detergent as it is cost-effective and eco-friendly.