Production of extra-cellular polymer in Azotobacter and biosorption of metal by exopolymer

Abstract

Two Azotobacter strains were isolated from alkaline and acid soils. The production of alginate and 
exopolymer from these two strains showed that, strain AC2 produced high polymer in 2% beet 
molasses or 1% sucrose broth and addition of nitrogen sources (yeast extract) reduced production of 
this polymer. The optimum condition for production of maximum polymer production (7.5 mg/ml) was at 
200 rpm shaking, pH 7 without addition of nitrogen sources. The production of polymer was reduced at 
pH 4. The polymer adsorbed Cu, Zn, and Fe, at 15.5, 20 and 25 mg, respectively.