Non-starch polysaccharides from sunflower (Helianthus annuus) meal and palm-kernel (Elaeis guineensis) meal--investigation of the structure of major polysaccharides

For the identification and characterisation of major non-starch polysaccharides from sunflower (Helianthus annuus L) meat and palm-kernel (Elaeis guineensis Jacq) meal, extracts obtained by sequential alkaline extraction and delignification of the corresponding cell wall materials were subfractionated by graded ethanol precipitation and size-exclusion and adsorption chromatography. Determination of the sugar and glycosidic linkage composition of extracts and subfractions and intact cell wall materials allowed the identification and quantification of a variety of polysaccharides. In sunflower meal, cellulose (42% of total non-starch polysaccharides), pectic polysaccharides (24%),(4-O-methyl)-glucuronoxylans with 8-11% uronic acid substitution (24%), (gluco)mannans (5%) and fucoxyloglucans (4-5%) were encountered. Major polysaccharides in palm-kernel meal were linear mannans with very low galactose substitution (78% of total non-starch polysaccharides), followed by cellulose (12%) and small amounts of (4-O-methyl)-glucuronoxylans and arabinoxylans (3% each).