黄原胶降解菌BIT-BJ001培养条件的优化

Optimization of Fermentation Conditions for Xanthan Gum-degrading Strain BIT-BJ001

黄原胶在采油工程中有重要的应用,但其难降解性质给采油工程带来很多问题。从塔里木油田胡杨木根部样品中分离得到1株黄原胶降解菌BIT-BJ001,对其发酵条件的研究表明,此黄原胶降解菌最适培养条件为:黄原胶0.3%,酵母粉0.5%,Na+浓度0.8%,Mg2+浓度0.8%,初始pH值为10,温度60℃。菌种BIT-BJ001降解黄原胶的能力与发酵时间、发酵液中还原糖浓度有关,发酵96 h,黄原胶降粘率达到最高,发酵液中还原糖浓度过高,将抑制菌株对黄原胶的降解。

Xanthan gum plays important roles in oil production engineering, however, its features of difficuh-to-de- grade has created a lot of problems for more application in oil production engineering. A xanthan-degrading bacteria was isolated from the root of diverslform-leaved poplar （Populus euphratica ） of Tarim, and named BIT-BJ001. The optimal medium composition in shake scale for xanthan-degrading strain BIT-BJ001 were determined as follows： xanthan gum O. 3% , yeast extract 0.5% , Na ＋ 0.6% , and Mg2 ＋ 0.8% at the initial pH 10, the optimum culture temperature was 60℃ as well. The degradation ability was related to culture time and concentration of reducing sugar. The highest rate of viscosity decrease was appeared after 96 h fermentation, in addition, over-high concentration of reducing sugar would inhibit the strain to degrade xanthan gum in the medium.