Oligosaccharides derived from the xyloglucan isolated from the seeds of Hymenaea courbaril var. stilbocarpa.
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 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 beta-D-glucan backbone partially substituted with side chains at O6 of alpha-D-xylopyranose, some of which were themselves substituted at O2 by the units of beta-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.
Lima
N N
NN
Department of Chemistry, Pontificia Universidade Católica, Curitiba, Paraná, Brazil.
Rechia
C G
CG
Ganter
J L
JL
Reicher
F
F
Sierakowski
M R
MR
D001938:Brazil; D002236:Carbohydrate Conformation; D002240:Carbohydrate Sequence; D002480:Cellulase / Q000378:metabolism; D002854:Chromatography, Paper; D007887:Fabaceae / Q000737:chemistry*; D008401:Gas Chromatography-Mass Spectrometry; D005936:Glucans; D006868:Hydrolysis; D009682:Magnetic Resonance Spectroscopy; D008969:Molecular Sequence Data; D009844:Oligosaccharides / Q000302:isolation & purification*; D010946:Plants, Medicinal; D011134:Polysaccharides / Q000737:chemistry*; D012639:Seeds / Q000737:chemistry; D012995:Solubility; D014867:Water; D014990:Xylans
D005936:Glucans; D009844:Oligosaccharides; D011134:Polysaccharides; D014990:Xylans; D014867:Water; C029353:xyloglucan; D002480:Cellulase