An Escherichia coli antimicrobial effect of arabinoglucomannan from fruit of Bryonia lacinosa

Extraction of the pulp of ripe berries of Bryonia lacinosa with 1% aqueous acetic acid yielded a polysaccharide material, having d-glucose, d-mannose and l-arabinose in the molar ratio of. 5.00:3.01:4.00. Hydrolysis of the fully methylated polysaccharide furnished 2,3,4,6-tetra-O-methyl-d-glucose, 2,3-di-O-methyl-d-glucose, 2,3,6-tri-O-methyl-d-mannose, 2,3-di-O-methyl-d-mannose and 2,3,5,-tri-O-methyl-l-arabinose in 1:4:2:1:4 molar ratio. Partial hydrolysis of the polysaccharide furnished; mannobiose, epicellobiose, 6-O-β-l-arabinofuranosyl-d-glucose, 6-O-α-mannopyranosyl-d-mannose and epimaltose along with the component monosaccharides. On metaperiodate oxidation studies, 100 g of the polysaccharide liberated 0.055 mol of HCOOH consuming 0.7127 mol of periodate, indicating about 8.33% of the end groups. On the basis of the above results, a structure for the repeating unit of the polysaccharide has been proposed. The polysaccharide was tested for the microbial activity and was found to be active against Escherichia coli with a minimum dose of 6.25 mg/mL.