Synthesis of propyl gallate by transesterification of tannic acid in aqueous media catalysed by immobilised derivatives of tannase from Lactobacillus plantarum

摘要

Immobilised derivatives of tannase from Lactobacillus plantarum were able to catalyse the transesterificationudof tannic acid by using moderate concentrations of 1-propanol in aqueous media. Transesterificationudof tannic acid was very similar to transesterification of methyl gallate. The synthetic yield depended onudthe pH and concentration of 1-propanol, although it did not vary much when using 30% or 50% 1-propanol.udSynthetic yields of 45% were obtained with 30% of 1-propanol at pH 5.0. The product was chromatographicallyudpure, and the reaction by-product was 55% pure gallic acid. On the other hand, immobilisedudtannase was fairly stable under optimal reaction conditions.