Cartwright C D, Owen S A, Thompson I P, Burns R G
Department of Biosciences, Research School of Biosciences, University of Kent, Canterbury, UK.
FEMS Microbiol Lett. 2000 May 1;186(1):27-34. doi: 10.1111/j.1574-6968.2000.tb09077.x.
Biodegradation of diethyl phthalate (DEP) has been shown to occur as a series of sequential steps common to the degradation of all phthalates. Primary degradation of DEP to phthalic acid (PA) has been reported to involve the hydrolysis of each of the two diethyl chains of the phthalate to produce the monoester monoethyl phthalate (MEP) and then PA. However, in soil co-contaminated with DEP and MeOH, biodegradation of the phthalate to PA resulted in the formation of three compounds, in addition to MEP. These were characterised by gas chromatography-electron ionisation mass spectrometry and nuclear magnetic resonance as ethyl methyl phthalate, dimethyl phthalate and monomethyl phthalate, and indicated the existence of an alternative pathway for the degradation of DEP in soil co-contaminated with MeOH. Transesterification or demethylation were proposed as the mechanisms for the formation of the three compounds, although the 7:1 ratio of H(2)O to MeOH means that transesterification is unlikely.
邻苯二甲酸二乙酯（DEP）的生物降解已被证明是通过一系列所有邻苯二甲酸酯降解共有的连续步骤进行的。据报道，DEP初级降解为邻苯二甲酸（PA）涉及邻苯二甲酸酯的两条二乙酯链各自水解，生成单酯单乙基邻苯二甲酸酯（MEP），然后生成PA。然而，在被DEP和甲醇共同污染的土壤中，邻苯二甲酸酯降解为PA除了产生MEP外，还导致形成了三种化合物。通过气相色谱 - 电子电离质谱和核磁共振对这些化合物进行了表征，它们分别是邻苯二甲酸乙酯甲酯、邻苯二甲酸二甲酯和邻苯二甲酸单甲酯，这表明在被甲醇共同污染的土壤中存在DEP降解的另一条途径。虽然水与甲醇的比例为7:1意味着不太可能发生酯交换反应，但仍有人提出酯交换或脱甲基作用是形成这三种化合物的机制。
