应用T-RFLP技术研究五氯酚对好氧颗粒污泥中细菌组成的影响

Effect of Pentachlorophenol (PCP) on Bacterial Community of an Aerobic Granular Sludge Estimated by T-RFLP

研究了五氯酚(PCP)对好氧颗粒污泥处理生活污水的影响,借助末端限制性酶切片段长度多态性(T-RFLP)技术考察了PCP存在时好氧颗粒污泥细菌组成的变化.结果表明,PCP对氨氮去除率的影响大于对COD去除率的影响,好氧颗粒污泥中微生物的种群数量随着PCP浓度的增加而逐渐减少,氨氮和COD去除率的变化与微生物种群数量变化相吻合.根据对PCP的敏感程度,好氧颗粒污泥中的微生物可分以下几类:①对PCP高度敏感的微生物,可能是Microbacterium或Streptococcus等以及2种未被报道的菌种;②对PCP中度敏感的微生物,可能是Corynebacterium或Nevskia等以及1种未被报道的菌种;③对PCP低度敏感的微生物,可能是Mycoplasma或Exiguobacterium等以及1种未被报道的菌种;④对PCP耐受性强的微生物,这类微生物主要是13个末端限制性片段(69、71、82、175、198、241、229、232、233、240、245、269、449bp)所代表的微生物,PCP浓度为30mg/L时,长度为82bp和175bp的片段的相对面积分别22.7%和13%,所代表的微生物已经演替为优势菌群.

Effect of pentachlorophenol （PCP） on COD and ammonium removal rates was investigated, and also changes of bacterial community within aerobic granular sludge were monitored by terminal restriction fragment length polymorphisrn （T-RFLP） technique. Compared with the removal rate of COD, the rate of ammonium removal is more sensitive to PCP. As the ammonium and COD removal rates decreased consistently, the bacterial genera within the aerobic granular sludge also decrease with the increase of PCP concentration. According to the response of PCP, the bacteria could be categorized into four groups as follows： ①The most sensitive organisms such as Microbacterium, Streptococcus and two new kinds of microorganisms; ② The more sensitive microorganisms such as Corynebacterium, Nevskia. and another unreported bacterium; ③The lower sensitive organisms encompassing Mycoplasma, Exiguobacterium, and another microorganism which has not been reported yet; ④ The PCP-tolerant organisms, including microorganisms indicated by 13 TRFs are represented as 69, 71, 82, 175, 198, 241, 229, 232, 233, 240, 245, 269 and 449bp. To most noticeable, TRF relative areas of the microorganisms indicated by TRFs 82bp and 175bp achieve 22.7% and 13%, respectively, and become predominant within the aerobic granular sludge with the PCP concentration at 30mg/L.