Rice bran lipase: Extraction, activity, and stability

A simple procedure for the extraction of the lipolytic activity from rice b ran has been developed. Various conditions of extraction have been optimize d so as to obtain maximum yield of the lipase. It was found that high enzym e activity could be obtained by first defatting the rice bran to remove the lipid component. This was followed by five cycles of aqueous extraction (p otassium phosphate buffer, 50 mM and pH 7, containing 0.5 mM of CaCl2). The stability of the rice bran lipase under storage and operative conditions w as investigated. Further, the influence of glycerol as a stabilizer has bee n assessed. It was found that further purification using micro- and ultrafi ltration yielded an enzyme preparation with higher activity and specific ac tivity and better stability.