Plant mucilages. XLII. An anti-complementary mucilage from the leaves of Malva sylvestris var. mauritiana.

A mucilage, designated as MSL-M, was isolated from the leaves of Malva sylvestris L. var. mauritiana Mill. It was homogeneous on electrophoresis and gel chromatography. Its intrinsic viscosity value in aqueous solution was 12.0, and its molecular weight was estimated to be about 6.0 x 10(6). The major constituent is an acidic polysaccharide composed of L-rhamnose: D-galactose: D-galacturonic acid: D-glucuronic acid in the molar ratio of 6:3:2:2. Methylation analysis of both the mucilage and the carboxyl-reduced derivative, carbon-13 nuclear magnetic resonance and partial hydrolysis studies indicated its main structural features. It has considerable anti-complementary activity.