Abstrait

Chemical analysis of water soluble polysaccharide isolated form medicinal plant Leucaena Leucocephala

Prashant Singh, Amar Bahadur

In the present paper we experimentally showthat polysaccharides extracted form defated seeds of Leucaena leucocephala is water soluble with ash content 0.41% and have negligible content of methoxyl, acetyl and uronic acid. Acidic hydrolysis of polysaccharide gave D-galactose and D-mannose in the molar ratio 1: 4. Graded hydrolysis, librated galactose first, indicates that these residues were present at end groups. Methylated polysaccharides having 25 11.20 D   (chloroform) and hydrolysis gave 2,3,6 tri o-Methyl D-mannose, 2,3-di-o-methyl, D-mannose and 2,3,4,6-terta-omethylD- galactose in themolar ratios 2:3:2. Periodate oxidation shows 25% end group and this result accord with methylation studies. Partial hydrolysis of polysaccharidewith 0.05 inH2SO4 at 100Cfor 12hr gavemannobiose, mannotriose, galactosyl mannobiose together with galactose and mannose. The experimental observation indicates that polysaccharide is a (14)--D mannose substituted at position 6 by galactosyl group.