壬基酚初级生物降解产物的辨认

为分析污水生物处理过程中壬基酚的去除机制,采用混合基质加标对照培养活性污泥、单一基质培养优势菌群2种生物降解实验,结合气相色谱-质谱谱图解析,从分子水平分析了壬基酚初级代谢产物和代谢途径.研究结果表明,活性污泥降解壬基酚的初级代谢产物主要为C4-C6烷基取代苯酚,烷基链的结构差异与其母体壬基的异构方式有关,烷基上的支链主要为甲基;优势降解菌群代谢壬基酚的初级产物除烷基苯酚外,还有苯乙酸等.污水生物处理过程中壬基酚可能的初级生物代谢途径是壬基上的长支链断裂为短的甲基链,生成一系列带有不同分支结构的短链烷基酚类代谢产物,进一步的代谢产物有苯乙酸.根据烷基酚类物质的内分泌干扰特性,短链烷基酚仍然具有雌激素活性,因此在壬基酚污染防治过程中应给与足够的重视.

Recognition and Analysis on Primary Metabolites of Nonylphenol

In order to discuss the nonylphenol (NP) biodegradability effect in the wastewater treatment process, the primary metabolites and route of NP had been analyzed in the molecular level by the interpretation of gas chromatography mass spectrometry (GC-MS) and the two experimental methods. A method was that activated sludge degraded two types of simulating sewage comparatively. Type-1 wastewater was made up of water, glucose, peptone and inorganic salts, and type-2 sewage was mixed up of NP and type-1 as comparison wastewater. The other experiment was that dominant bacteria group metabolized the culture medium contained NP as only organic carbon source. The results show that the NP primary metabolites from the activated sludge experiments are a series of short chain alkyl phenols with butyl, amyl or hexyls. There are different methyl branch structures correlated with isomerous nonyl of NP in the alkyls. The primary metabolites from the dominant bacteria experiment have alkyl phenols and benzene acetic. The bio-degradation pathways of NP would be that the long branches in nonyl of NP are firstly degraded into short methyl branches, which come into being a series of short chain alkyl phenols with different branch structures. The middle products should be further metabolized into simpler compounds, such as benzene acetic. Based on the endocrine disrupter characteristic of alkyl phenol compounds, the short chain alkyl phenol compounds still have estrogen hormone effect, and their environmental effect must be pay attention in the pollutant control of NP.