Isolation of a novel lipase producing fungal isolate Aspergillus fumigatus and production optimization of enzyme

Fungal lipases occupy a place of prominence among biocatalysts owing to their novel, multifold applications and resistance to high temperature and other operational conditions. In the present study, Aspergillus fumigatus isolated from oil-contaminated soil produced good amount of lipase activity with galactose (1%) as carbon source and peptone (0.1%) as nitrogen source after 72 h of incubation in the production medium at 45 degrees C and pH 10.0. The isolated enzyme was found to give its optimum reaction temperature at 40 degrees C and pH 9.0 with the substrate used as p-nitrophenyl benzoate. The activity of lipase was inhibited by the presence of metal ions. A 6.68-fold increase for lipase production was obtained by one variable at a time. Based on the findings of present study, lipase of A. fumigatus is a potential lipase and a candidate for industrial applications such as bioremediation, detergent, leather and pharmaceutical industries.