Lipase Production by Yarrowia lipolytica in Solid-State Fermentation Using Amazon Fruit By-Products and Soybean Meal as Substrate

Abstract

The production of polyunsaturated fatty acids from fish oil, which is related to various health benefits including effects against cardiovascular diseases, antihypertensive, anticancer, antioxidant, antidepression, anti-aging, and anti-arthritis effects, among others, can be advantageously performed through the application of lipase. However, the high cost associated with enzyme production can make the process unfeasible and thus alternative substrates should be investigated to solve these problems. This research aimed to produce lipase by Yarrowia lipolytica IMUFRJ50682 in solid-state fermentation using by-products of the food processing industry (andiroba oil cake and soybean meal) and verify the potential application in the initial hydrolysis of fish oil to further produce polyunsaturated fatty acids in a suitable process. A screening was carried out for the analysis of andiroba oil cake and soybean meal combinations in different proportions (0:100 to 100:0, respectively) at 48 h of the fermentation process. Afterward, the solid matrix composed by soybean meal and andiroba oil cake was supplemented with soy oil and Tween 80 to improve the lipase activity. The enzymatic extract was characterized in relation to the protein profile by electrophoresis. Finally, the enzymatic extract and the solid biocatalyst produced were applied to evaluate the potential hydrolysis of the fish oil in an initial study. Maximum lipolytic activity (63.7 U·g−1) was achieved using andiroba oil cake and soybean meal (50:50) after 24 h of fermentation. Soybean oil 1.5% and Tween 80 (0.001%) in an emulsion provided an increase of 1.5-fold (82.52 U·g−1) in the enzyme activity. The electrophoretic analysis demonstrated a band between 37 and 40 kDa that may be related to lipase and a band of 75 kDa referring to the α subunit of the β-conglycinin present in soybean meal. After 48 h, the solid biocatalyst showed a higher degree of hydrolysis (DH) (71.0%) than the enzymatic extract (61.5%). The solid biocatalyst was stable during storage at room temperature for 7 months. The production of lipases using Amazon fruit by-product and soybean meal in solid-state fermentation is viable as well as the application of the extract and solid biocatalyst in the initial application for the hydrolysis of fish oil to further produce polyunsaturated fatty acids in an industrially suited process.