Simultaneous production of fatty acid methyl esters and diglycerides by four recombinant Candida rugosa lipase’s isozymes

In this study, the catalytic efficiency of four recombinant CRL (Candida rugosa lipase) isozymes (LIP1–LIP4) towards the production of fatty acid methyl ester (FAME) was compared and evaluated as an alternative green method for industrial applications. The results indicated that the recombinant C. rugosa LIP1 enzyme exhibited the highest catalytic efficiency for FAME production compared to the recombinant C. rugosa LIP2–LIP4 enzymes. The optimal conditions were as follows: pH 7.0, methanol/soybean oil molar ratio: 3/1, enzyme amount: 2 U (1.6 μL), reaction temperature: 20 °C, 22 h of reaction time, and 3 times of methanol addition (1 mol/6 h), and resulted in 61.5 ± 1.5 wt.% of FAME conversion. The reaction product contained also 10 wt.% of DAG with a ratio of 1,3-DAG to 1,2-DAG of approximately 4:6, and can be potentially used in industrial applications as a food emulsifier.