Mohn W W, Kennedy K J
Division of Biological Sciences, National Research Council Canada, Ottawa, Ontario.
Appl Environ Microbiol. 1992 Jul;58(7):2131-6. doi: 10.1128/aem.58.7.2131-2136.1992.
To better understand the fate of chlorophenols treated in upflow anaerobic sludge bed reactors, we examined the ability of sludge granules from such bioreactors to degrade two trichlorophenols and one dichlorophenol in batch incubations under controlled conditions. Biodegradation was primarily limited to two distinct activities, reductive dehalogenation of ortho- and of meta-chlorine substituents. Both 3- and 4-monochlorophenol were persistent degradation products, while 2-monochlorophenol was further degraded. We also examined factors potentially affecting the rate and extent of 2,3,6-trichlorophenol degradation. An initial concentration of up to 1.75 mM (346 mg/liter) was dehalogenated. At that concentration, dehalogenation was partially inhibited but methanogenesis from formate was not. The initial concentration affected both the extent of dehalogenation and which products were detected. The maximum dechlorination rate observed was 1.4 mumol of Cl- h-1 g of volatile suspended solids-1. Dechlorination had a temperature optimum of 50 degrees C, was inhibited by added electron acceptors, and was not appreciably affected by added electron donors. The availability of electron acceptors and electron donors did not affect the extent of chlorophenol degradation. These particular sludge granules do not appear to be capable of mineralizing phenols with meta- or para-chlorine substituents.
为了更好地了解上流式厌氧污泥床反应器中处理的氯酚的归宿，我们在受控条件下的分批培养中，研究了来自此类生物反应器的污泥颗粒降解两种三氯酚和一种二氯酚的能力。生物降解主要限于两种不同的活性，即邻位和间位氯取代基的还原脱卤。3-和4-一氯酚都是持久性降解产物，而2-一氯酚则进一步降解。我们还研究了可能影响2,3,6-三氯酚降解速率和程度的因素。高达1.75 mM（346毫克/升）的初始浓度发生了脱卤反应。在该浓度下，脱卤反应受到部分抑制，但甲酸盐的产甲烷作用未受影响。初始浓度既影响脱卤程度，也影响检测到的产物。观察到的最大脱氯速率为1.4微摩尔Cl-每小时每克挥发性悬浮固体。脱氯的最适温度为50℃，添加电子受体可抑制脱氯，添加电子供体对脱氯没有明显影响。电子受体和电子供体的可用性不影响氯酚的降解程度。这些特定的污泥颗粒似乎无法将带有间位或对位氯取代基的酚矿化。
