title: Enzymatic polymerization of coniferyl alcohol in the presence of cyclodextrins.
abstract: The dehydrogenative polymerization of coniferyl alcohol by horseradish peroxidase was performed in 0.10 M phosphate buffer at 27 degrees C. Dehydrogenative polymer (DHP) from coniferyl alcohol was characterized by size exclusion chromatography (SEC) and nuclear magnetic resonance (NMR) spectroscopy. The ratio of 8-O-4':8-5':8-8' linkages was determined by the 1H NMR spectrum of DHP acetate which had good solubility. In "end-wise like" polymerization (the slow addition of hydrogen peroxide), addition of alpha-cyclodextrin to the medium led to DHP with increased 8-O-4' content and a decrease in 8-5' linkages. Under higher pH conditions, DHP with higher 8-O-4' and 8-5' content was obtained in the presence of alpha-cyclodextrin. In the end-wise polymerization (the slow additions of coniferyl alcohol and hydrogen peroxide), using alpha-cyclodextrin also gave DHP with a 8-O-4' richer structure than that prepared in no additive system. The analysis of thioacidolysis products from DHP supported the results of the alpha-cyclodextrin effects on the 8-O-4'-rich structure of DHP. The 8-O-4' structure in DHP prepared in the presence of alpha-cyclodextrin had racemic form as shown by ozonation.
authors.affiliation: Graduate School of Bioagricultural Sciences, Nagoya University, Chikusa-ku, Nagoya 464-8601, Japan, and Toyota Central R&D Laboratries, Nagakute, Aichi 480-1192, Japan.
authors.forename: Rikiya
authors.initials: R
authors.lastname: Nakamura
authors.forename: Yasuyuki
authors.initials: Y
authors.lastname: Matsushita
authors.forename: Kazuhiko
authors.initials: K
authors.lastname: Umemoto
authors.forename: Arimitsu
authors.initials: A
authors.lastname: Usuki
authors.forename: Kazuhiko
authors.initials: K
authors.lastname: Fukushima
mesh_terms: D000818:Animals; D031215:Armoracia; D006735:Horseradish Peroxidase / Q000737:chemistry*; D006863:Hydrogen-Ion Concentration; D015394:Molecular Structure; D010316:Particle Size; D010636:Phenols / Q000737:chemistry*; D011108:Polymers / Q000138:chemical synthesis*; D013237:Stereoisomerism; D047391:alpha-Cyclodextrins / Q000737:chemistry*
chemical_list: D010636:Phenols; D011108:Polymers; D047391:alpha-Cyclodextrins; C010559:coniferyl alcohol; D006735:Horseradish Peroxidase