产黄原胶酶菌种的选育及发酵条件的研究

从自然界中采集土壤样品,经筛选获得了1株产高活性黄原胶酶的菌种,经形态特征、培养特征、生理生化分析等试验,初步鉴定为鞘氨醇单胞菌属Sphingomonassp.。摇瓶发酵产酶实验表明,培养基适宜初始pH值为7.0;适宜培养温度为30℃;适宜底物浓度为1%;葡萄糖和硝酸铵分别是适宜的碳源和氮源;用250 mL三角瓶以30 mL装液量进行发酵,酶活力较高。适宜菌龄为16~24 h,接种量对发酵影响不大。在上述条件下黄原胶酶的酶活力最高可达466 IU/L。

Isolation of A Xanthase-producing Strain and Optimization of Its Fermentation Conditions

A xanthase-producing bacterium strain was isolated from soil and was identified as Sphingomonas sp..The effects of different factors on the enzyme production were studied.Glucose and(NH_4)NO_3 were the preferable C and N source. The optimized initial pH for the strain growth and production of xanthase was 7.0.The optimized temperature for the strain growth and production of xanthase was 30℃.The bacterium cultured with 30 mL of the medium in 250 mL flask was preferable.The amount of inoculums was not an important factor for the result of fermentation.The maximum xanthase activity reached 466 IU/L when the stain was cultured under the above optimized conditions.