Characterisation of cell wall polysaccharides from rapeseed (Brassica napus) meal.
To enable structural characteristics of individual cell wall polysaccharides from rapeseed (Brassica napus) meal (RSM) to be studied, polysaccharide fractions were sequentially extracted. Fractions were analysed for their carbohydrate (linkage) composition and polysaccharide structures were also studied by enzymatic fingerprinting. The RSM fractions analysed contained pectic polysaccharides: homogalacturonan in which 60% of the galacturonic acid residues are methyl-esterified, arabinan branched at the O-2 position and arabinogalactan mainly type II. This differs from characteristics previously reported for Brassica campestris meal, another rapeseed cultivar. Also, in the alkali extracts hemicelluloses were analysed as xyloglucan both of the XXGG- and XXXG-type decorated with galactosyl, fucosyl and arabinosyl residues, and as xylan with O-methyl-uronic acid attached. The final residue after extraction still contained xyloglucan and remaining (pectic) polysaccharides next to cellulose, showing that the cell wall matrix of RSM is very strongly interconnected.
Wageningen University, Laboratory of Food Chemistry, Bomenweg 2, 6703 HD Wageningen, The Netherlands.
Annemieke M
AM
Pustjens
Henk A
HA
Schols
Mirjam A
MA
Kabel
Harry
H
Gruppen
D029688:Brassica napus / Q000737:chemistry*; D002240:Carbohydrate Sequence; D002473:Cell Wall / Q000737:chemistry*; D002852:Chromatography, Ion Exchange; D057075:Enzyme Assays; D005685:Galactans / Q000737:chemistry / Q000302:isolation & purification; D005936:Glucans / Q000737:chemistry / Q000302:isolation & purification; D006603:Hexuronic Acids / Q000737:chemistry / Q000302:isolation & purification; D008969:Molecular Sequence Data; D010368:Pectins / Q000737:chemistry / Q000302:isolation & purification; D011134:Polysaccharides / Q000737:chemistry / Q000302:isolation & purification; D019032:Spectrometry, Mass, Matrix-Assisted Laser Desorption-Ionization; D014990:Xylans / Q000737:chemistry / Q000302:isolation & purification
D005685:Galactans; D005936:Glucans; D006603:Hexuronic Acids; D011134:Polysaccharides; D014990:Xylans; C030080:araban; C029353:xyloglucan; C007819:galacturonic acid; C007916:hemicellulose; D010368:Pectins; C005653:arabinogalactan; C003181:polygalacturonic acid
Brassica napus; Cell wall polysaccharides; Enzymatic fingerprinting; Linkage type; Rapeseed meal