Production Conditions of Exopolysaccharide from Bacillus megaterium Identified by 16S rRNA Gene Sequencing

THE BACILLUS megaterium exopolysaccharide (EPS) producer was isolated from the Egyptian soil and identified by molecular biology technique (16S rRNA). It was found that the exopolysaccharide showed a high yield after 72 hr, with an initial pH of 5.0, in 250 ml Erlenmeyer flasks containing 50 ml of culture, the medium having 2% sucrose as a sole carbon source. The yeast extract (0.1%) and ammonium chloride (0.1%) were the best organic and inorganic nitrogen source, respectively, as they gave the maximum EPS production. Optimum incubation temperature was found to be 35 C. Pretreated molasses from sugarcane and sugarbeet were used as a carbon source and they gave a considerable yield (~ tow fold) in relation to sucrose. The pretreatment of molasses by sulfuric acid showed a high yield of polysaccharide and maximum yield coefficient.