Production of Acidic protease using Submerged Fermentation by Rhizopus arrhizus

Abstract

The study is concerned with utilize whey of milk factory as a carbon source for the production of protease. The project was planned to produce maximum protease from whey by Rhizopus arrhizus at pH 4 and 37 °C temperature. Growth media employed to culture Rhizopus arrhizus for the production of enzyme were developed and fermentation conditions was optimized through various trials. Substrate water ratio, different nitrogen sources and concentration of nitrogen source were optimized. The fermented materials were harvested after 72 hours. These were filtered and centrifuged at 10,000 rpm at -10 °C. The filtrates were subjected to enzyme assay. Absorbance of the enzyme sample was determined at 700 nm on spectrophotometer. It was observed that 90% Whey and 2.5% cotton seed meal enhanced the production of protease by Rhizopus arrhizus. Maximum enzyme activity was observed (149.26 IU/ml/min) in flask level at pH 4 and 37 °C temperature. These optimized conditions of growth media was again used in Air-Lift fermenter and determined the activity (169.78 IU/ml/min) that is greater than flask level. This is due to proper aeration and proper temperature in Air-lift fermenter.

Keywords: Acidic protease, Air-lift fermentor, submerged fermentation and Rhizopus arrhizus