Production of Protease by Geotrichum candidum in Solid-state Fermentation Using Deoiled Jatropha curcas Seed Cake as Substrate

摘要

The interest in using Jatropha curcas seed oil as a feedstock for the production of biodiesel is rapidly growing, and there will generate huge quantity of deoiled Jatropha curcas seed cake (JCSC). Its safe disposal or meaningful utilization is very important. This article reports our studies on the utilization of this huge biomass by solid-state fermentation (SSF) for the production of protease. Geotrichum candidum strain was purchased and used for fermentation. Maximum protease production (1527 U/g of dry substrate, U/gds) was obtained at 100% substrate moisture, a growth period of 4 days, a substrate pH range of 6.5-7.0, and 10% of wheat bran supplementation, respectively. Enrichment with 10% of maltose and 5% of glucose as carbon source increased protease production by 360.6% and 189.2%, respectively. These results indicated viable approach for utilization of this huge biomass by solid-state fermentation to produce industrial enzyme, which may reduce the ever-increasing production cost of biodiesel to some extent on the other hand.