Regenerative Immobilized Lipase System Activated by Food‐Derived Fatty Acids for Efficient Hydrolysis of Vegetable Oils

ABSTRACT A practical lipase‐based hydrolysis system for fats and oils is of great interest for the industrial production of fatty acids for food applications. However, the high cost of enzymes has limited enzymatic fatty acid production to the laboratory scale. In this study, we developed a simple and cost‐effective regenerative hydrolysis system for vegetable oils (soybean oil and rapeseed oil) using an immobilized lipase that exhibited high activity, long‐term stability, and efficient regeneration without loss of function. Lipase AY Amano 30G derived from Candida rugosa was immobilized on Duolite A‐568 (weakly basic ion exchange resin). The addition of food‐derived fatty acids, such as soybean and rapeseed fatty acids, during immobilization by physical adsorption enhanced the lipase activity by more than two‐fold. After optimizing immobilization conditions and operating circulating reactions for over 700 h (repeated reactions achieving splitting ratio of 90% or higher), the system achieved a high initial activity of 2100 U/g, a low inactivation rate constant of 0.00067 h −1 , and a half‐life of 1.5 months. Reuse of the immobilization carrier is critical for practical applications, and we found that fatty acids generated during hydrolysis served as natural activators for re‐immobilizing lipases on reused carriers. Residual fatty acids could be effectively removed using n‐hexane without compromising enzyme activity. The activity and durability of regenerated immobilized lipases were comparable to those of freshly prepared enzymes in repeated circulating reactions. This study demonstrates an environmentally favorable approach for the enzymatic production of food‐grade fatty acids and provides a foundation for scaling to practical industrial applications.