Polysaccharides of Winged Beans (Psophocarpus tetragonolobus [L.] DC), Variety TPT-2

Variety TPT-2 contains little or no starch. Hot water extraction of defatted and partially deproteinized flour yielded soluble and insoluble polysaccharide fractions in yields of 11 and 28%, respectively. Fractional precipitation of the soluble polysaccharides yielded a predominant Fraction I and a minor Fraction II. Fraction I contained 96% polysaccharide. Fraction II and the insoluble fraction contained 81 and 72% polysaccharide, respectively, the remainder being protein, ash and lignin. Fraction I polysaccharide is predominantly (76%) galactan, but it also contains 18% uranic acid. The Fraction II polysaccharide appears to be predominantly arabinogalactan, but contains 15% uranic acid. Cellulose (41%), galactan (25%), xylan (14%) and acidic polysaccharides (15%) predominate in the insoluble polysaccharides.