ENZYMATIC-SYNTHESIS OF GERANYL ACETATE IN N-HEXANE WITH CANDIDA-ANTARCTICA LIPASES

Geranyl acetate is an important flavor and fragrance compound. Two immobilized Candida antarctica lipases, SP382 and SP435, were investigated for their use in the synthesis of geranyl acetate by direct esterification. Yields between 95 and 99% molar conversion were obtained with 2 and 15% (whv reactants) of SP435 and SP382 lipases, respectively. Optimum yields were obtained at 0.1M acetic acid and 0.12M geraniol after 16-h incubation. No inhibitory effect was observed at increasing concentrations of geraniol. Addition of 60% (w/w reactants) water led to 50 and 60% reduction in the esterification activity of SP382 and SP435 lipases, respectively. The best yields were obtained at added water contents between 0-5% (w/w reactants). Solvents with a log P value of 0.85 or more gave reaction yields of more than 80% molar conversion. Higher log P values did not necessarily lead to higher conversion yields. The immobilized lipase SP382 was still active after reusing ten times in the direct esterification reaction.