Production of lipase enzyme from Rhizopus oryzae by solid state fermentation and submerged fermentation using wheat bran as substrate

Abstract

Production of lipase enzyme from Rhizopus oryzae was developed by solid state fermentation (SSF) and submerged fermentation (SmF) method in order to yield high amount of lipase enzyme using wheat bran as the substrate. The objective of this research is to obtain the crude lipase enzyme from Rhizopus oryzae by optimizing the operating condition of submerged fermentation method, compare the unit activity of lipase enzyme produced by SSF and SmF, and synthesize the biodiesel via non-alcohol route using lipase enzyme as the catalyst. The optimum condition for the production of lipase is discovered by varying the fermentation time, substrate concentration, and inducer concentration. The fermentation time was varied at 1, 3, 5, and 7 days with substrate concentration was varied at 0.5%, 1%, 1.5%, 2%, and 2.5%, and inducer concentration was varied at 2%, 4%, 6%, and 8%. The extraction of lipase enzyme was done by squeezing the suspension through muslin cloth, centrifugation, and then filtered by filter paper. Titration was done as the enzymatic assay for the lipase activity. Based on results, optimum condition of submerged fermentation has been achieved with inducer concentration of 6.9%, substrate concentration of 1.9%, and fermentation time of 3.5 days. This condition results the unit activity of lipase of 62.67 U/ml and 50 U/ml, for SmF and SSF, respectively. Furthermore, for biodiesel synthesis through non-alcohol route, lipase enzyme from Rhizopus oryzae was able to yield 38.11% of biodiesel.