Enzymatic synthesis of structured lipids: Transesterification of triolein and caprylic acid ethyl ester

Structured lipids were successfully synthesized by lipase‐catalyzed transesterification (ester interchange) of caprylic acid ethyl ester and triolein. The transesterification reaction was carried out in organic solvent as reaction media. Eight commercially‐available lipases (10% w/w substrates) were screened for their ability to synthesize structured lipid by incubating with 100 mg triolein and 78.0 mg caprylic acid ethyl ester in 3 mL hexane at 45°C for 24 h. The products were analyzed by reverse‐phase high‐performance liquid chromatography with evaporative light‐scattering detector. Immobilized lipase IM60 fromRhizomucor miehei converted most triolein into structured lipids (41.7% dicapryloolein, 46.0% monocapryloolein, and 12.3% unreacted triolein). However, lipase SP435 fromCandida antarctica had a higher activity at higher temperature. The reaction catalyzed by lipase SP435 yielded 62.0% dicapryloolein, 33.5% monocapryloolein, and 4.5% unreacted triolein at 55°C. Time course, incubation media, added water, and substrate concentration were also investigated in this study. The results suggest that lipase‐catalyzed transesterification of long‐chain triglycerides and medium‐chain fatty acid ethyl ester is feasible to synthesize structured lipids.