Screening, Optimization and Process Scale up for Pilot Scale Production of Lipase by Aspergillus niger

An enzyme with various commercial purpose, lipase is a carboxy esterase enzyme with many uses in different industries. Multiple isolates of Aspergillus niger were isolated from oil contaminated soil samples and screened for lipase producing ability on tributyrin medium. The isolate showing maximum activity was identified and subjected to growth parameters optimization in attempt to increase the enzyme producing ability of the isolate in larger scale. Different media with varying composition were examined for best lipase production. The activities of the lipase produced by the fungus at various pH were assessed. The enzyme activity was determined by the titration method. Maximum lipase activity of 2.4 U/ml was achieved with organic nitrogen rich media (designated as PM II) at pH 7 on the sixth day of culture. The lipase production was scaled up on a pilot scale in a 5 Liter fermenter maintaining growth parameters of pH 7, temperature at 28°C, stirrer rate at 120 rpm, airflow rate at 30 L/hr, O2 saturation 50% and pressure 0.05 MPa. The crude enzyme was extracted for further assays. Optimization of the parameters can improve the productivity as well as the quality of the enzyme produced.