Characteristics And Analysis Of Xanthan-degrading Enzyme

The oligosaccharide was produced from xanthan by hydrolysis with the supernatant of the strain LB37. The aim of this experiment to research the optimal culture condition for the cell growth and enzyme production of xanthan liquefying.One strain depolymerizing xanthan has been isolated and designed as LB37. The optimal culture condition for the cell growth and enzyme production was determined. The best carbon source and nitrogen source for growing was xanthan and tryptone respectively. The optimum concentration of carbon source for xanthan liquefying enzyme production is0.35%and the optimum concentration of nitrogen source is0.1%. The result showed that the optimum culture temperature is30℃and pH is6. The maximal xanthan liquefying enzyme activity was obtained when LB37was cultured for40h. The strain cannot grow at pH lower than2. The result showed that the optimum temperature for enzymatic reaction is40℃and pH is5.8. The enzyme is thermostable at40℃for3h. Xanthan liquefying enzyme was purified by ammonium sulfate, and the saturation is30%-60%. Ultrafiltration to determine the original molecular weight range of Xanthan-liquefying is between the10000Da～20000Da. And the result was identified through SDS-PAGE.