Lipase-catalysed acidolysis for enrichment of medium-chain triacylglycerols in virgin coconut oil and its functional properties

Lipase-catalysed acidolysis has emerged as a promising biocatalytic approach for producing structured lipids. In particular, the enrichment of medium-chain triacylglycerols (MCTs) in oils <i>via</i> lipase catalysis is attracting great attention due to their health benefits. In addition, MCTs are a known source of instant energy. In the current work, the immobilized lipase-catalysed enrichment of medium-chain triacylglycerols (MCTs) in a virgin coconut oil (VCO) matrix was achieved. Lipase -catalysed acidolysis of VCO with caprylic (C8:0) and capric acids (C10:0) was conducted to enhance the concentration of MCTs in a solvent-free system, employing two commercial lipases, Lipozyme RM IM from <i>Rhizomucor miehei</i> (1,3-specific) and Novozym 435 from <i>Candida antarctica</i> (non-specific). This study investigated various reaction parameters, including substrate molar ratio, reaction time, and temperature, using Lipozyme RM IM to optimize the catalytic conditions. A higher incorporation of capric acid was observed compared to caprylic acid when the reactions employed 10% lipase relative to the total mass of substrates at a molar ratio of oil to a mixture of caprylic and capric acids (50% each) of 1 : 4. The optimal conditions for achieving the highest MCT enrichment (∼42%) involved a reaction time of 8 h at 40 °C. The MCT enrichment in the VCO was evidenced by ¹³C NMR with inverse-gated ¹H-decoupling, GC, and HRMS. The structured VCO exhibited enhanced antimicrobial activity against selected foodborne pathogens while demonstrating no cytotoxic effects in <i>in vitro</i> cell viability assays, supporting its functional safety. These findings highlight the potential of enzymatically structured VCO as a value-added functional lipid for food and nutraceutical applications.