Oligosaccharides derived from the xyloglucan isolated from the seeds of Hymenaea courbaril var. stilbocarpa

• Published in: International journal of biological macromolecules 1995-12, Vol.17 (6), p.413-415
• Main Authors: Lima, Nery N., Rechia, Carem G.V., Ganter, Joana Lea M.S., Reicher, Fany, Sierakowski, Maria Rita
• Format: Article
• Language: English
• Subjects: Brazil; Carbohydrate Conformation; Carbohydrate Sequence; Cellulase - metabolism; Chromatography, Paper; Fabaceae - chemistry; Gas Chromatography-Mass Spectrometry; Glucans; Hydrolysis; Hymenaea courbaril; Magnetic Resonance Spectroscopy; Molecular Sequence Data; oligosaccharides; Oligosaccharides - isolation & purification; Plants, Medicinal; Polysaccharides - chemistry; Seeds - chemistry; Solubility; Water; Xylans; xyloglucans
• ISSN: 0141-8130; 1879-0003
• DOI: 10.1016/0141-8130(96)81855-1

On aqueous extraction, Hymenaea courbaril var. stilbocarpa, known in Brazil as jatobá, furnishes a high yield of viscous xyloglucan (45%) from its seeds. The crude polysaccharide (B1) was hydrolysed and the products, analysed as alditol acetates, were glucose, xylose, galactose and arabinose in the ratio 50:35:13:2. After further fractionation on a DEAE-cellulose column (chloride form), the main fraction (70% yield, B2) was obtained. The basic structure of the xyloglucan was determined as a cellulose-type (1 → 4)-linked β- d-glucan backbone partially substituted with side chains at 06 of α- d-xylopyranose, some of which were themselves substituted at 02 by the units of β- d-galactopyranose. Treatment of the xyloglucan (B2) with commercial cellulase from Trichoderma sp. yielded six oligosaccharides. These oligosaccharides were isolated by preparative paper chromatography, and their structures were determined by gas-liquid chromatography-mass spectroscopy of the derived partially O-methylated alditol acetates. These results confirm the structure proposed for jatobá seed xyloglucan.