Structural characterization of xilooligosaccharides from shoots of woody bamboo species

ZELAYA, VICTOR MARTÍN; FERNADEZ, PAULA VIRGINIA; CIANCIA, MARINA

Simposio; Glycobiology Symposium; 2019

Bamboo is one of the mostly fast growing natural resources, and it has great potential to be used as a valuable feedstock for biorefinery. Bamboo shoots are the new culms that arise from the rhizomes, containing nodes and internodes in a vertically miniaturized form. Young shoots of Phyllostachys aurea and Guadua chacoensis (Poales) showed glucuronoarabinoxylans (GAX) as the major hemicellulosic components, being extracted in important quantities with 1M KOH (12.1% and 10.3% of the cell wall material, ratio Xyl:Ara:GlcA, 100:67:8 and 100:28:8, respectively). Their structure was determined by methylation analyses and NMR spectroscopy. The degree of ramification of both xylans was very different, so they were considered appropriate substrate models for enzymatic treatment.GAX was treated with Driselase ® (a mixture of endo- and exo-enzymes) to generate xylo-oligosaccharides (XOS). Yields of digestion were 80% and the oligosaccharides were fractionated by size-exclusion chromatography on Biogel P-2 using water as eluant. Analysis of the oligosaccharides showed mixtures of xylans with different DP and the presence of a -(13)-glucan, so efforts were done to eliminate this contaminant before digestion.Elucidation and understanding of the pure xilooligosaccharides from bamboo play an important role in the efficient conversion of bamboo into bioproducts