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The effects of soybean and castorbean meals were evaluated separately, and in combinations at different ratios, as substrates for lipase production by Botryosphaeria ribis EC-01 in submerged fermentation using only distilled water. The addition of glycerol analytical grade (AG) and glycerol crude (CG) to soybean and castorbean meals separately and in combination, were also examined for lipase production. Glycerol-AG increased enzyme production, whereas glycerol-CG decreased it. A 2(4) factorial design was developed to determine the best concentrations of soybean meal, castorbean meal, glycerol-AG, and KH2PO4 to optimize lipase production by B. ribis EC-01. Soybean meal and glycerol-AG had a significant effect on lipase production, whereas castorbean meal did not. A second treatment (2(2) factorial design central composite) was developed, and optimal lipase production (4,820 U/g of dry solids content (ds)) was obtained when B. ribis EC-01 was grown on 0.5 % (w/v) soybean meal and 5.2 % (v/v) glycerol in distilled water, which was in agreement with the predicted value (4,892 U/g ds) calculated by the model. The unitary cost of lipase production determined under the optimized conditions developed ranged from US$0.42 to 0.44 based on nutrient costs. The fungal lipase was immobilized onto Celite and showed high thermal stability and was used for transesterification of soybean oil in methanol (1:3) resulting in 36 % of fatty acyl alkyl ester content. The apparent K m and V max were determined and were 1.86 mM and 14.29 μmol min(-1) mg(-1), respectively.

The objective of this work was to develop efficient methods to increase the extraction yield of bioactive components from passion fruit seed oil. The extraction kinetics with hexane/ethanol/water solvents for the chemical process and with lipase together with these solvents for the chemical + enzymatic process was assessed, considering different extraction times and temperatures. It was verified that the chemical extractions were the most efficient conditions at temperature of 30°C and at 5 min, 15 min, and 24 h of extraction time and at temperature of 45°C for only 2.5 min of extraction time. It was found that chemical together with enzymatic extraction had lower yields than chemical extraction. Regarding mathematical modeling, it was found that the best fits were represented by first order, So and MacDonald's and hyperbolic models, whose results indicate that these equations can be applied to simulation and design studies. Novelty impact statement In this article, it was found that chemical extractions were the most efficient conditions at temperature of 30°C and at 5 min, 15 min, and 24 h of extraction time and at temperature of 45°C for only 2.5 min of extraction time. In addition, regarding mathematical modeling, it was found that the best fits were represented by first order, So and MacDonald's and hyperbolic models, whose results indicate that these equations can be applied to simulation and design studies.

An ecofriendly and low‐cost film composed by cassava starch, polyvinyl alcohol, and sericin blend (CS–PVA–SS) was synthesized, characterized, and applied as a novel support for Botryosphaeria ribis EC‐01 lipase immobilization by enzyme–film–enzyme adsorption. Film revealed thickness between 230 and 309 μm and higher flexibility and malleability in comparison with film without SS. Based on p‐nitrophenyl palmitate hydrolysis reaction, the activity retention of immobilized lipase was 987%. For optimal conditions, the yield in ethyl oleate was 95% for immobilized enzyme. Maximum yield was obtained at 49°C, molar ratio oleic acid:ethanol of 1:3, 1.25 g lipase film or 50 U (1.03 ± 0.03 mg protein) and 30 h. Even after seven cycles of use, immobilized lipase showed 52% reduction in ester yield. Biodegradable and biorenewable film is a promising material as a support to immobilize lipases and application in biocatalysis.

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