School of Life Science and Biotechnology, Dalian University of Technology, Dalian, P. R. China.
J Environ Sci Health B. 2011;46(3):257-63. doi: 10.1080/03601234.2011.540534.
In this study, an Alcaligenes sp. strain DG-5 that can effectively degrade dichlorodiphenyltrichloro-ethanes (DDTs) under aerobic conditions was isolated from DDTs-contaminated sediment. Various factors that affect the biodegradation of DDTs by DG-5 were investigated. About 88 %, 65 % and 45 % of the total DDTs were consumed within 120 h when their initial concentrations were 0.5, 5 and 15 mg L⁻¹, respectively. However, almost no degradation was observed when their concentration was increased to 30 mg L⁻¹, but the addition of nutrients significantly improved the degradation, and 66 % and 90 % of the total DDTs were degraded at 336 h in the presence of 5 g L⁻¹ peptone and yeast extract, respectively. Moreover, the addition of 20 mM formate also enhanced the ability of DG-5 to transform DDTs, and its DDT transformation capacity (T(c)) value was increased by 1.8 - 2.7 fold for the pure (p,p'-DDT or o,p'-DDT only) and mixed systems (p,p'-DDT, o,p'-DDT, p,p'-DDD and p,p'-DDE). Furthermore, it was found that competitive inhibition in the biodegradation by DDT compounds occurred in the mixed system.
在这项研究中，从滴滴涕污染的沉积物中分离到一株能够在好氧条件下有效降解滴滴涕的产碱杆菌（Alcaligenes sp. ）DG-5 菌株。研究了影响 DG-5 生物降解滴滴涕的各种因素。当初始浓度分别为 0.5、5 和 15 mg/L 时，在 120 h 内，总滴滴涕的消耗率约为 88%、65%和 45%。然而，当浓度增加到 30 mg/L 时，几乎没有降解，但是添加营养物质显著提高了降解效率，在存在 5 g/L 蛋白胨和酵母提取物的情况下，分别在 336 h 内降解了 66%和 90%的总滴滴涕。此外，添加 20 mM 甲酸盐也增强了 DG-5 转化滴滴涕的能力，其滴滴涕转化能力（T(c)）值在纯（p,p'-DDT 或 o,p'-DDT 仅）和混合系统（p,p'-DDT、o,p'-DDT、p,p'-DDD 和 p,p'-DDE）中分别增加了 1.8-2.7 倍。此外，还发现混合系统中滴滴涕化合物的生物降解存在竞争抑制。
Zotero 插件