Enzyme‐Catalyzed Synthesis of Saccharide Acrylate Monomers from Nonedible Biomass

Abstract

Various cellulase preparations were found to catalyze the transglycosidation between cotton linters and 2-hydroxyethyl acrylate. The conversion and enzyme activity were found to be optimal in reaction mixtures that contained 5 vol % of the acrylate. The structures of the products were revealed by using TLC and (1) H and (13) C NMR spectroscopy. The enzyme-catalyzed reaction resulted in two products. The minor product originated from transglycosidation to hemicellulose and was found to be 2-(β-xylosyloxy)-ethyl acrylate. The major product was identified as 2-(β-glucosyloxy)-ethyl acrylate and the yield of the product was 5 wt % based on the amount of consumed cellulose. Glycosidation products with oligosaccharide moieties could not be detected in the reaction mixture. This result can be explained by the hydrolytic activities of the used cellulase preparation. Cellulase from Trichoderma reesei was found to possess, in addition to endoglucanase activity, cellobiosidase and β-glucosidase activities. Five other cellulase preparations from different origins were tested as well for catalysis of oligosaccharide acrylate synthesis. For most cellulase preparations the major transglycosidation product appeared to be 2-(β-glucosyloxy)-ethyl acrylate. Nevertheless, the endo-β-(1,4)-glucanase from Trichoderma longibrachiatum was found to catalyze the synthesis of 2-(β-cellobiosyloxy)-ethyl acrylate. Unlike the other cellulase preparations, endo-β-(1,4)-glucanase from T. longibrachiatum showed no detectable β-glucosidase activity and therefore oligosaccharide acrylate monomers were not further hydrolyzed into the monosaccharide acrylate 2-(β-glucosyloxy)-ethyl acrylate.

Bioinspired Enzymatic Synthesis of Terpenoid-Based (Meth)acrylic Monomers: A Solvent-, Metal-, Amino-, and Halogen-Free Approach

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Biocatalytic Synthesis of Furan-Based Oligomer Diols with Enhanced End-Group Fidelity

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Green Synthesis of Glycopolymers Using an Enzymatic Approach

“…To the best of our knowledge, none of these reports utilized enzymes as alternative catalysts to synthesize glycopolymers. The role of enzymes was so far limited to the preparation of sugar‐based monomers to avoid tedious protection steps of the saccharide‐hydroxyl groups in conventional synthetic reactions . In an effort to achieve complete green and sustainable processes in glycopolymer synthesis, enzymes are ideal candidates as a catalyst for the polymerization since they are nontoxic, obtained from renewable materials, and typically work under mild reaction conditions …”