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) meal 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).