一株烃降解菌Rhodococcus ruber Z25研究

Rhodococcus ruber Z25,a hydrocarbon-degradating strain

烃降解菌株Z25分离自大庆油田中新201区块采油污水样，经形态观察和16S rDNA基因序列分析，鉴定为Rhodococcus Puber Z25．该菌株在20～45℃，0～5％盐的质量浓度下生长良好，适宜生长温度为30～40℃，最适盐的质量分数为2．5％．Rhodococcus rube rZ25菌株能以液体石蜡为唯一碳源生长并合成糖脂类生物表面活性剂，发酵48h，细菌生物量和糖脂产量分别为1．53g／L和13．22g／L．经气相色谱对Rhodococcus rube rZ25菌株在好氧和厌氧条件下原油降解的全烃组分分析，结果表明：该菌株在好氧条件下优先降解石油中的轻烃组分，在厌氧条件下优先降解石油中的重烃组分．

A hydrocarbon-degradating strain was isolated from the oil production water of Zhongxin 201 Unit inDaqing Oilfield. The strain was identified to be Rhodococcus ruber Z25 by morphology and 16S rDNA sequencing. The strain was able to grow at a wide range of temperature （20 - 45 ℃ ） and salinity （0 ～ 5.0% ） with the suitable growth condition being at NaC1 concentration of 2. 5% at 30 -40℃ . In batch fermentation, the strain could utilize liquid paraffin as sole carbon source and synthesize biosurfactant. The maximum biomass and biosurfactant production were obtained at 48 h with the values of 1.53 and 13.22 g/L, respectively. The biodegradation test of crude oil was conducted under aerobic and anaerobic conditions. The alkanes components in the crude oil were analyzed by gas chromatography. The test results showed that the strain Rhodococcus ruber Z25 had a preference of utilizing light components under aerobic condition and degradating heavy components under anaerobic condition.