Utilization of oleochemical industry residues as substrates for lipase production for enzymatic sunflower oil hydrolysis

The present work deals with the production of lipase by Candida rugosa ATCC 14830 and focuses on the effect of different substrates on lipase production by submerged fermentation. Two industrial wastes from oil refining and the oleochemical industry were evaluated as substitutes to olive oil for lipase production through aerobic fermentation. Lipase activity, protein yield and cell mass were studied using different substrates concentrations. First, olive oil (00), fatty acid residues (FAR) and soapstock (SS) were tested individually as substrates. The activities of the produced lipases, utilizing these substrates, were found to be 12 U/ml, 7 U/ml and 7.4 U/ml, respectively. Second, a mixture of these substrates composed of fatty acid residues, olive oil, and soapstock (POS) were formulated and used for lipase production. The obtained results showed that the lipase activity achieved was 10 U/ml. The produced lipase has been used in sunflower oil hydrolysis. The results revealed that 39.5% of the original tested sunflower oil was hydrolyzed into free fatty acids after 24 h at 37 degrees C. (C) 2013 Elsevier Ltd. All rights reserved.