Polysaccharides ofUngernia. X. Pectins from the leaves ofUngernia sewerzowii

The characteristics of the pectin from the leaves ofUngernia sewerzowii are given. The pectin isolated consists of residues of: galacturonic acid — 51%; rhamnose — 23.6%; arabinose — 4.9%, xylose — 1.3%; glucose — 4.1%; and galactose — 15.3%, [α]D25+206° (c 0.5; water, OCH3 — 5.4%. Partial hydrolysis of the pectin gave a galacturonan containing only galacturonic acid residues. On the basis of the results of periodate-silver nitrate oxidation and methylation it was shown that the galacturonic acid residues in the galactone are linked by α-1 → 4-glycosidic bonds.