ANAEROBIC BIODEGRADATION OF 2,4,5-TRICHLOROPHENOXYACETIC ACID IN SAMPLES FROM A METHANOGENIC AQUIFER - STIMULATION BY SHORT-CHAIN ORGANIC-ACIDS AND ALCOHOLS
ANAEROBIC BIODEGRADATION OF 2,4,5-TRICHLOROPHENOXYACETIC ACID IN SAMPLES FROM A METHANOGENIC AQUIFER - STIMULATION BY SHORT-CHAIN ORGANIC-ACIDS AND ALCOHOLS
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DOI：
10.1128/aem.56.6.1825-1832.1990
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发表时间：
1990-06-01
影响因子：
4.4
通讯作者：
SUFLITA, JM
中科院分区：
文献类型：
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作者：
GIBSON, SA;SUFLITA, JM
利用甲烷含水层中的除草剂2，4，5-三氯苯氧基乙酸(2，4，5-T)进行脱卤化反应，生成2，4-和2，5-二氯苯氧基乙酸作为首次检测中间体。含水层泥浆的进一步孵化导致几种中间体的形成，包括一氯苯氧基乙酸、二氯苯酚和一氯苯酚以及苯酚。在高压灭菌对照中，没有检测到母体底物的转化或中间产物的产生。中间产物的形成模式表明，2，4，5-T的厌氧降解是通过一系列的脱卤化步骤进行的，侧链裂解反应发生在环裂解之前的某个点。短链有机酸或醇的加入促进了2，4，5-T脱卤化的开始和速率，并减少了实验结束时仍可检测到的卤化中间体的母体底物的数量。无论是否在含水层泥浆中添加补充碳，添加硫酸盐都会对脱卤化产生相反的影响。硫酸盐对脱卤化的抑制作用有时可以被钼酸盐缓解，尽管这种作用似乎与所使用的补充碳化合物有关。
The herbicide 2,4,5-trichlorophenoxyacetic acid (2,4,5-T) was dehalogenated in samples from a methanogenic aquifer to form 2,4- and 2,5-dichlorophenoxyacetic acids as the first detected intermediates. Further incubation of the aquifer slurries resulted in the formation of several intermediates including monochlorophenoxyacetic acids, di- and monochlorophenols, as well as phenol. No transformation of the parent substrate or production of intermediates was detected in autoclaved controls. The pattern of intermediate formation suggested that the anaerobic degradation of 2,4,5-T proceeded by a series of sequential dehalogenation steps with side-chain cleavage reactions occurring at some point before ring cleavage. The addition of short-chain organic acids or alcohols stimulated the onset and rate of 2,4,5-T dehalogenation and decreased the amount of parent substrate still detectable as halogenated intermediates at the end of the experiment. Sulfate addition had the opposite effect on dehalogenation regardless of whether supplemental carbon was added to the aquifer slurries. The inhibitory effect of sulfate on dehalogenation could sometimes by relieved with molybdate, although this effect seemed to be related to the supplemental carbon compound that was used.