title: One-step synthesis of cellulose from cellobiose via protic acid-assisted enzymatic dehydration in aprotic organic media.
abstract: Direct and efficient enzymatic synthesis of long-chain cellulose from cellobiose in its original form was successfully achieved via the combination of a surfactant-enveloped enzyme (SEE) and a protic acid in an aprotic organic solvent, lithium chloride/N,N-dimethylacetamide system. The SEE biocatalyst was prepared by protecting the surface of cellulase with the nonionic surfactant dioleyl-N-D-glucona-L-glutamate for keeping its enzymatic activity in nonaqueous media. Fourier transform infrared and nuclear magnetic resonance analyses elucidated the successful synthesis of cellulose, β-1,4-linked D-glucopyranose polymer, through the reverse hydrolysis of cellobiose. By using protic acid cocatalysts, a degree of polymerization of as-synthesized cellulose reached more than 120, in a ca. 26% conversion, which was 5 times higher than that obtained in an acid-free SEE system. A novel-concept biocatalysis, i.e., a protic acid-assisted SEE-mediated reaction, enables a facile, one-step chain elongation of carbohydrates without any activation via multistep organic chemistry, and can provide potential applications in the functional design of glycomaterials.
authors.affiliation: Department of Agro-Environmental Sciences, Graduate School of Bioresource and Bioenvironmental Sciences, and Biotron Application Center, Kyushu University, 6-10-1 Hakozaki, Fukuoka, 812-8581 Japan.
authors.forename: Shizuka
authors.initials: S
authors.lastname: Egusa
authors.forename: Masahiro
authors.initials: M
authors.lastname: Goto
authors.forename: Takuya
authors.initials: T
authors.lastname: Kitaoka
mesh_terms: D055162:Biocatalysis; D002475:Cellobiose / Q000737:chemistry*; D002480:Cellulase / Q000737:chemistry*; D002482:Cellulose / Q000138:chemical synthesis*; D006868:Hydrolysis; D018021:Lithium Chloride / Q000737:chemistry*; D009682:Magnetic Resonance Spectroscopy; D012997:Solvents / Q000737:chemistry; D017550:Spectroscopy, Fourier Transform Infrared; D013464:Sulfuric Acids / Q000737:chemistry*; D013501:Surface-Active Agents / Q000737:chemistry*; D014867:Water
chemical_list: D012997:Solvents; D013464:Sulfuric Acids; D013501:Surface-Active Agents; D014867:Water; D002475:Cellobiose; D002482:Cellulose; D002480:Cellulase; D018021:Lithium Chloride; C033158:sulfuric acid