Chitosan-based CLEAs from Aspergillus niger type A feruloyl esterase: high-productivity biocatalyst for alkyl ferulate synthesis.

Chitosan-based CLEAs from Aspergillus niger type A feruloyl esterase: high-productivity biocatalyst for alkyl ferulate synthesis. Appl Microbiol Biotechnol. 2020 Oct 07;: Authors: Grajales-Hernández D, Armendáriz-Ruiz M, Velasco-Lozano S, López-Gallego F, Mateos-Díaz JC Abstract The enzymatic synthesis of alkyl ferulates is an important reaction in cosmetic and pharmaceutical chemistries, since it may allow to expand the biorefinery concept valorizing biomass wastes enriched in ferulic acid. However, robust biocatalysts for that purpose are scarce. Herein, we have immobilized the type A feruloyl esterase from Aspergillus niger (AnFaeA) as cross-linked enzyme aggregates, employing chitosan as co-feeder (ChCLEAs). High immobilization yields and relative activity recovery were attained in all assessed conditions (> 93%). Furthermore, we enhanced the thermal stability of the soluble enzyme 32-fold. AnFaeA-ChCLEAs were capable to quantitatively perform the solvent-free direct esterification of short- to medium-chain alkyl ferulates (C4-C12) in less than 24 h. By raising the operational temperature to 50 °C, AnFaeA-ChCLEAs transformed 350 mM ferulic acid into isopentyl ferulate with a space-time yield of 46.1 g of product × L-1 × day-1, 73-fold higher than previously reported. The overall sustainability of this alkyl ferulate production bioprocess is supported by the high total turnover number (TTN 7 × 105) and the calculated gr...
Source: Applied Microbiology and Biotechnology - Category: Microbiology Authors: Tags: Appl Microbiol Biotechnol Source Type: research