SRB菌的分离鉴定及其对矸石山酸性废水的处理

为了得到煤矸石山酸性废水处理的专属功能微生物,从湖南湘潭某煤矸石山周边土壤中分离筛选硫酸盐还原菌,分析菌株的16S rRNA基因序列,形态和生理生化特性,并利用得到的菌株处理矸石山酸性废水。16S rRNA基因序列分析表明,所分离得到的硫酸盐还原菌株S-7与Desulfuromonas alkenivorans同源性达到99.0%。该菌株为杆状稍有弯曲,能运动,大小(0.5~0.8)μm×(3.0~4.0)μm,革兰氏染色显阴性,最适生长温度为30℃,最适p H值范围6~8,酵母粉为最好的碳源和氮源,硫酸钠为最适合硫源,菌株经培养96 h后细胞浓度高达1.76×109个/m L。培养初始p H为7时,6 d可去除体系中90%硫酸根离子,而不同硫酸根离子浓度对菌株生长和硫酸盐去除效率影响不明显。S-7菌株对矸石山酸性废水中Fe,Mn,Pb和Zn四种重金属离子均存在处理效果,整体上去除效率为PbFeZnMn,其中Pb离子经7 d处理后去除率达到100%。

Isolation and identification of SRB and its utilization on processing of acid mine drainage of coal gangue dump

In order to obtain the proper microbes to process the acid mine drainage from coal gangue dump，the sulfate-reducing strain was isolated from surrounding soil of a coal gangue dump in Xiangtan City，Hunan Province，China.The 16S rRNA gene sequence，morphology，physiological and biochemical characteristics of isolated strain and its application on processing acid mine drainage were investigated.The 16S rRNA gene analysis shows that the strain S-7 has 99% phylogenic similarity with Desulfuromonas alkenivorans.The strain is slightly curved rods；the motile，with size (0.5-0.8)μm×(3.0-4.0)μm，appears as Gram-negative；and the optimum growth temperature and pH are 30 ℃ and 6-8 respectively.The yeast powder is considered as the best carbon and nitrogen source，sodium sulfate as best sulfide source.After 96 h cultivation，the highest concentration of cells is up to 1.76×109 per/mL.At initial pH=7 culture solution，the sulfate removal rate is up to 90% after 6 d cultivation.However，the different sulfate concentrations have no obvious effect on strain growth and sulfate removal rate.The S-7 strain has a better processing effect on Fe，Mn，Pb and Zn ions in the acid mine drainage of coal gangue dump，and the remove rate follows the order of Pb>Fe>Zn>Mn.Among of them，the removal rate of Pb is up to 100% after 7 d processing.