Enzymatic Synthesis of a Capsinoid by the Acylation of Vanillyl Alcohol with Fatty Acid Derivatives Catalyzed by Lipases

Abstract

  Capsinoids are a novel group of compounds produced by the Capsicum plant. We synthesized a capsinoid by the lipase-catalyzed esterification of vanillyl alcohol with fatty acid derivatives in an organic solvent. The use of seven out of 17 commercially available lipases, especially Novozym 435, was applicable to the synthesis of vanillyl nonanoate, a model compound of capsinoids. The yield of vanillyl nonanoate under the optimum conditions of 50 mM vanillyl alcohol and 50 mM methyl nonanoate in 500 μl of dioxane, using 20 mg of Novozym 435 and 50 mg of 4 Å molecular sieves at 25°C, was 86% in 20 h. Several capsinoid homologues having various acyl chain lengths (C6–C18) were synthesized at 64–86% yields from the corresponding fatty acid methyl ester. The natural capsinoids, capsiate and dihydrocapsiate, were obtained by a 400-fold-scale reaction at these optimum conditions in 60% and 59% isolated yields, respectively.