Adding value to the oil cake as a waste from oil processing industry: Production of lipase in solid state fermentation

Riccinus communis (castor) seed cake is a by-product generated after oil extraction from the seed. This deoiled seed cake contains a toxic protein ricin that restricts its application in livestock feed. In the present study, solid-state fermentation (SSF) was used to value addition in castor de-oiled cake (CDOC). It was used as a substrate for the production of lipase under SSF using different fungal species. Initially, seven fungal strains were grown on CDOC and out of seven, only four are able to grow on it. From these four strains, only two Aspergillus oryzae (NCIM 1212) and Aspergillus japonicas (MTCC no. 1975) were observed to produce lipase. The effect of different physical parameter viz., moisture content, pH and incubation time on lipase production were also determined. The maximum lipase yield was determined to be 25 U/gm. Maximum enzyme production was observed at 6th day of incubation. The optimum condition for the lipase production was pH 7.0, moisture content 100%. From these results, it can be concluded that CDOC could be a good and cheap substrate for lipase production through SSF.