Production of a Bioflocculant by Mixed Culture

抄録

Colony groups that form large amounts of slime externally were obtained from activated sludge among phthalate-assimilating microbes. That slime, which R-3 mixed microbes produced externally, had a high level of flocculation activity. R-3 mixed strains, one of such colony groups, efficiently produced a bioflocculant (APR-3) in liquid cultures of production medium, especially that containing starch and glucose (1 : 1) as carbon sources. Identitication of this group of bioflocculant-producing microbes (R-3 mixed strains) showed that it was comprised of four strains belonging to the genera Oerskovia, Acinetobacter, Agrobacterium, and Enterobacter. The bioflocculant (APR-3) was purified electrophoretically to homogeneity by ethanol and CPC precipitation. Its molecular mass is at least 2×10⁶ Da. APR-3 is an acidic polysaccharide made of glucose, galactose, succinic acid, and pyruvic acid (molar ratio : 5.6 : 1 : 0.6 : 2.5).