苯酚降解菌红球菌(Rhodococcus sp.) P1的鉴定及其在焦化废水中的应用

Characterization of phenol-degrading Rhodococcus sp. strain P1 from coking wastewater

摘要:

摘要:【目的】酚类物质的去除是焦化废水处理的关键问题，目的是从焦化废水中分离高效的苯酚降解细菌。【方法】以苯酚为唯一碳源筛选纯化降解苯酚细菌，菌株鉴定采用菌落形态和16S rRNA 序列分析方法，并研究其苯酚降解特性和在焦化废水中的除酚作用。【结果】菌落形态和16S rRNA序列比对分析表明分离的P1菌株为红球菌属(Rhodococcus sp.)细菌;其耐酚浓度高达1400 mg/L，苯酚降解的最适条件为32℃－42℃、pH 7.0和0－4%盐;苯酚降解动力学曲线符合Haldane动力学模型，qmax=0.517/h，Ks=77.487 mg/L，Ki=709.965 mg/L;不同重金属对红球菌P1菌株的苯酚降解抑制作用不同，Zn2+、Mn2+和低浓度的Pb2+对菌株降酚没有影响，Cu2+、Ni2+、Cd2+均抑制菌株对酚的降解;红球菌P1菌株2d内可完全降解1/3焦化原水中的279.9 mg/L酚类物质。【结论】P1菌株是1株高效的苯酚降解菌，具有生物处理焦化废水酚类物质的潜力。

Abstract:

Abstract:［Objective］The removal of phenolic compounds was a key problem for coking wastewater treatment. This study focused on the isolation and characterization of anefficient phenol-degrading bacterial strain from coking wastewater.［Methods］Phenol-degrading bacterium was screened by using phenol as the sole carbon source，strain was identified according to the morphological properties and 16S rRNA sequence analysis，the phenol-degrading characteristics and the potential for removal of phenol in the coking wastewater were evaluated.［Results］Strain P1 was identified as the genus Rhodococcus sp. with morphological properties and 16S rRNA gene sequence. This strain could survive at the presence of phenol with concentration up to 1400 mg/L. The optimal conditions for biodegradation of 600 mg/L phenol in mineral medium were at 32－42℃，pH 7.0 and 0－4% NaCl. The phenol-degrading efficiency by P1 strain was different in response to various heavy metal ions，Ni2+，Mn2+ and low concentration of Pb2 + had no effect on the phenol degradation．However，Cu2+ ，Ni2+ and Cd2+ seriously inhibited phenol degradation by strain P1. The 279.9 mg/L phenols from 1/3 coking wastewater were completely degraded after incubation for 2days.［Conclusion］Strain P1 is an efficient phenoldegrading bacterium and has of the potential for removing phenolic compounds in coking wastewater.