Structure of xylan from culms of bamboo grass (Sasa senanensis Rehd.)

Abstract

Xylan prepared from culms of kumaizasa (Sasa senanensis Rehd.), a representative species of bamboo grass, was hydrolyzed with β-xylanase of Streptomyces olivaceoviridis E-86. Four arabinoxylo-oligosaccharides and two glucuronoxylo-oligosaccharides were isolated from the enzymatic hydrolysate of the xylan by chromatography on a charcoal column, a Dowex 1-×8 column, a Toyo-pearl HW-40S column, and a LiChrospher 100 NH2 column and on preparative paper chromatography. The results of the structural analyses of the saccharides showed that the isolated oligosaccharides had the structures of 32-α-L-arabinofuranosyl-xylobiose, 32-α-L-arabinofuranosyl-xylotriose, 32-α-[β-D-xylopyranosyl-(1 → 2)-L-arabinofuranosyl]-xylobiose, 33-α-[β-D-xylopyranosyl-(1 → 2)-L-arabinofuranosyl]-xylotriose, 23-α-4-O-methyl-D-glucuronosyl-xylotriose, and 23-α-D-glucuronosyl-xylotriose. From the structural analysis of the oligosaccharides derived from the xylan, kumaizasa xylan was concluded to be a kind of arabinoglucuronoxylan having not only stubs of single L-arabinose and single D-glucuronic acid but also stubs of disaccharide units such as β-D-xylopyranosyl-(1 → 2)-L-arabinofuranose. The Japan Wood Research Society 1998.