Isolation of wild Xanthomonas strains from agricultural produce, their characterization and potential related to polysaccharide production.

One hundred fifty wild strains of Xanthomonas were isolated on five selective and nonselective media. The comparative effectivity of the five media has been discussed. Fifteen polysaccharide-producing strains shortlisted were identified up to species level. These were studied for polysaccharide production in shake flasks using YM media. The highest final yield of 21.3 g/L of the amount of carbon source supplied has been obtained in the optimum medium in shake-flask experiments from Xanthomonas campestris (ICa-125 strain isolated from cabbage. Rheological properties of the exocellular polysaccharide (EPS) have been compared with standard xanthan. EPS from X. campestris ICa-125 was found to be superior with respect to heat stability and effect of electrolytes as compared to standard xanthan.