CHARACTERIZATION OF PECTIC POLYSACCHARIDES FROM PULSE HUSKS

Pectic polysaccharides were isolated from the husks of field bean (Dolichos lab lab), cowpea (Vigna sinensis) and pea (Pisum sativum), using HCl (pH 2.0) and 0.5% EDTA at extractants at 70 degrees C, in yields varying from 1.43 to 5.37%. Pectic polysaccharide obtained by 0.5% EDTA extraction was more viscous and gave a higher yield than acid-extracted ones. Acetyl and methoxyl groups had no effect on the viscosities of the polysaccharides. Their compositional analysis indicated mainly arabinose, rhamnose and xylose in addition to high amounts of uronic acid.