Cell walls of leaves from native woody bamboo Guadua chacoensis (Poaceae, Bambusoideae, Bambuseae)

FERNÁNDEZ, P. V.; ANDREA S. VEGA; CIANCIA, M.

Ciudad de Buenos Aires

Simposio; 1er Simposio Argentino de Glicobiología, GlycoAr 2014; 2014

IBYME e Instituto Leloir

Guadua chacoensis (Rojas) Londoño & P. M. Peterson is a native woody bamboo that grows in Northeastern Argentina. It represents a renewable resource that can provide polysaccharides and oligosaccharides with different potential applications, and it can also be used as forage. A detailed knowledge of cell wall polysaccharides is required to develop those applications. To reach this goal, the alcohol insoluble residue from leaves of G. chacoensis was subjected to a sequential extraction comprising hot water, 0.05M CDTA, 0.05M Na2CO3, 1M and 4M KOH. As expected, yields and composition of the extracts showed that pectins are minor components of these cell walls, meanwhile hemicelluloses and cellulose are their major carbohydrate constituents. Accordingly, the major extract, which was obtained with KOH 1M (11% of the cell wall mass), consists of xylose, arabinose, glucose and galactose (56%, 26%, 10% and 8%, respectively). Methylation analysis and NMR spectra show the typical structure of an arabinoxylan, with a main chain composed of β-(1→4)-Xylp units, with a complex pattern of substitution that includes arabinofuranosyl, galactosyl and glucuronosyl residues combined in different arrays. Small amounts of mixed linkage glucans, an hemicellulosic polymer characteristic of grasses, were detected in various cell wall extracts. Se incluye el pdf completo del libro de resúmenes. El resumen de este trabajo es el P12.