Exopolysaccharide production by some rhizobium strain in culture.

Eight Rhizobium strains were screened for exopolysaccharide production during growth in yeast extract mannitol medium. A strain of Rhizobium loti produced more than 250 mg of exopolysaccharide/100 ml of culture during the stationary phase of growth. Exopolysaccharide production was favoured by maltose and mannitol but N2 supplementation could not affect the production siginificantly. Preliminary studies indicate that the polymer contains 16% protein and 73.5% carbohydrate being composed of glucose, galactose and glucuronic acid.