الفهرس 
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Abstract
A polysaccharide was isolated from Lentil seeds (Giza 9) in 0.5-3.5% yield, and was purified via its copper complex. Hydrolysis of the polysaccharide affforded D-galactose, D-xylose, L-arabinose and L-rhamnose in the molar ratio 5:4:7:1 respectively. Periodate oxjjdation of the polymer resulted in the consumption of ten molar equivalents of the oxidant and the liberation of
three molar equivalents of formic acid per seventeen anhydroaldose units containing the above saccharides and
in the ratio referred to above. After oxidation by periodat6
rhamnose, D-xylose and L-arabinose that had escaped oxidation were observed to occur in the hydrolysate in the molar ratio
1:2:7, thus offering information about the positions of linkages and branching in the polysaccharide. An evaluattion of the molecular weight of the polymer was carried OU·’.:; by treatment with sodium borohydride followed by oxidation by sodium metaperiodate and subsequent estimation of the formaldehyde that had been liberated by the oxidation.
The specific optical rotations of the polysaccharide in alkali (Ca +112.5~)and in cuprammonium (Ca -222.20) indi-
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the polymer are not engaged.
The absorption spectrum of the polysaccharide showed that the linkages between the units were of theex-type.
In conclusion, a tentative formulation of the polyysaccharide was offered. It is suggested that the Lentil seed (Giza 9) contains a polysaccharide composed of a main straight chain of L-arabinofuranose units joined by
0( 1-3 linkages and that a branch is conneoted at C-5 of each third unit of L-arabinofuranose. Each side branch is of 2-4 units, and is composed of alternate D-galactose and D-xylose units in such a way that each D-galactopyranose unit is glycosidically joined to a ~xylopyranose unit through C-3 of ~xylose and that each Q-xylopyranose unit is glycosidically joined to a D-galactopyranose unit through C-4 of D-galactose. The branches are terminated by either a ~galactopyranose or a ~xylopyranose unit (XXXVIll) •