Lipase-catalyzed synthesis of laurate esters from puerarin and its β-D-fructofuranosyl-(2→6)-puerarin derivative

Abstract

This study investigates the transesterification of isoflavones puerarin and β-D-fructofuranosyl-(2→6)-puerarin to enhance their lipophilicity for specific pharmacological applications. The process achieved high yields (80-100%) in the isoflavones conversion when commercial lipases from Candida antarctica (CALB) and Thermomyces lanuginosus (TL IM) were used. The acylation patterns between CALB and TL IM varied depending on the substrate; both enzymes yielded principally monoacylated products from puerarin and β-D-fructofuranosyl-(2→6)-puerarin. However, TL IM also produced di- and triacylated derivatives of β-D-fructofuranosyl-(2→6)-puerarin in substantial amounts. Structural characterization by NMR identified puerarin-6ʹʹ-O-laurate and β-D-fructofuranosyl-(2→6)-puerarin-6ʹʹʹ-O-laurate as the primary products in CALB and TL IM reactions. These acyl derivatives presented improved lipophilicity (Log P from −1.0 − 0.16 to 3.26 − 3.58) and antioxidant activity (67.2-97.3 to 102.5-131.4 µM TE/mmol). Therefore, these compounds have potential pharmacological applications.