芘-铬(Ⅵ)复合污染的共脱毒菌株的分离鉴定及特性研究

Isolation,Identification and Characterization of Detoxification Bacterial Strains with Ability of Removing Pyrene-Cr(Ⅵ)Combined Pollution

成本低廉、高效、环境友好的微生物修复技术,是治理多环芳烃-重金属复合污染的良策.从温州市平阳县水头镇分离得到两株芘-铬(Ⅵ)共脱毒菌株F1和Z6,鉴定为Raoultella sp.和Serratia sp.,并对菌株的共脱毒性能进行研究.结果表明:F1菌株和Z6菌株的最适脱毒条件:温度30℃、pH 9.0,F1菌株接种量30%,Z6菌株接种量50%,两菌株在共脱毒时铬(Ⅵ)对芘降解有抑制,但芘对铬(Ⅵ)还原有轻微促进作用.Z6菌株的共脱毒能力优于F1菌株,优化条件后Z6菌株将20 mg/L铬(Ⅵ)完全还原,同时将50 mg/L芘降解率达60%,具有更大的应用潜力.

The low-cost,highly efficient,and environmentally friendly microbial remediation technology is a good strategy for treating combined pollution of PAHs and heavy metals.Two detoxification bacterial strains(F1 and Z6)with the ability of removing pyrene-Cr(Ⅵ)combined pollution,which were isolated from the area of Shuitou Town,Pingyang,Wenzhou,were identified as Raoultella sp.and Serratia sp..In addition,their ability of removing pyrene-Cr(Ⅵ)combined pollution was studied.Results showed that the optimal conditions of simultaneously removing pyrene and Cr(Ⅵ)for the stain F1 was pH 9.0,30℃and the inoculation amount of 30%,and that for the strain Z6 was pH 9.0,30℃and the inoculation amount of 50%.For both strains in the process of detoxification,Cr(Ⅵ)negatively affected pyrene biodegradation,while pyrene could slightly promote Cr(Ⅵ)reduction.In short,the strain Z6 has a better efficiency than the strain F1 in detoxification,and could completely reduce 20 mg/L Cr(Ⅵ)and biodegrade 60%of 50 mg/L pyrene simultaneously under the optimum conditions,thus has a greater potential for practical applicatio.