Enzymatic synthesis of bornyl linoleate in a solvent-free system

ABSTRACT In this study, bornyl linoleate was synthesized by enzymatic esterification of borneol with linoleic acid in a solvent-free system. The influences of lipase type, reaction temperature, substrate molar ratio, lipase load and reaction time on bornyl linoleate yield were evaluated. The results indicated that the optimal conditions were as follows: 8% AYS lipase as catalyst (w/w, relative to total reactants), reaction temperature of 45 °C, molar ratio of borneol to linoleic acid of 1:2 and 12 h duration. Under the conditions, the yield of bornyl linoleate was up to 92.62%. Afterwards, the crude product was purified by molecular distillation and solvent extraction-alkali neutralization, as well, the structure of the final product was identified by mass spectrometry and nuclear magnetic resonance. The results showed that the product was confirmed to be bornyl linoleate and the purity of which was 99.02%.