邻苯二甲酸酯(PAE)被广泛用作增塑剂,并已被归类为主要关注的普遍存在的环境污染物。PAE在地表水中大量积累,地下水和废水;因此,PAE降解至关重要。在本研究中,耐盐细菌(SSB)-聚生体降解具有不同长度烷基链的合成废水-邻苯二甲酸酯的能力,如邻苯二甲酸二乙酯(DEP),邻苯二甲酸二正丁酯(DBP),邻苯二甲酸苄丁酯(BBP),并对邻苯二甲酸二(2-乙基己基)酯(DEHP)进行了表征。应用中心复合材料设计-响应面方法来优化每种邻苯二甲酸酯的降解,其中独立变量是温度(21至41°C),pH(5.3至8.6)和PAE浓度(79.5至920.4mgL-1),气相色谱-质谱联用技术用于鉴定邻苯二甲酸酯降解过程中产生的代谢物。最佳条件为31°C,pH7.0,初始PAE浓度为500mgL-1,其中SSB财团去除84.9%,98.47%,初始DEP的99.09%和98.25%,DBP,BBP,和DEHP,分别,在168h。一级动力学模型解释了PAE降解的生物降解和半衰期范围为12.8至29.8h。通过细菌元分类学分析确定了SSB-聚生体的属分布。Serratia,甲基芽孢杆菌,不动杆菌,假单胞菌是主要的属;然而,邻苯二甲酸酯的类型直接影响其分布。扫描电子显微镜分析显示,高浓度(1000mgL-1)的邻苯二甲酸盐引起细菌(SSB)-聚生体的形态改变。代谢物分析显示DEP,DBP,BBP,和DEHP可以通过脱酯化和β-氧化途径完全代谢。因此,SSB财团可以被认为是生物修复复杂的邻苯二甲酸盐污染水资源的潜在候选者。
Phthalic acid esters (PAE) are widely used as plasticizers and have been classified as ubiquitous environmental contaminants of primary concern. PAE have accumulated intensively in surface water, groundwater, and wastewaters; thus, PAE degradation is essential. In the present study, the ability of a saline soil bacteria (SSB)-consortium to degrade synthetic wastewater-
phthalates with alkyl chains of different lengths, such as diethyl phthalate (DEP), di-n-butyl phthalate (DBP), benzyl butyl phthalate (BBP), and di (2-ethylhexyl) phthalate (DEHP) was characterized. A central composite design-response surface methodology was applied to optimize the degradation of each phthalate, where the independent variables were temperature (21-41 °C), pH (5.3-8.6) and PAE concentration (79.5-920.4 mg L-1), and Gas Chromatography-Mass Spectrometry was used to identify the metabolites generated during phthalate degradation. Optimal conditions were 31 °C, pH 7.0, and an initial PAE concentration of 500 mg L-1, where the SSB-consortium removed 84.9%, 98.47%, 99.09% and 98.25% of initial DEP, DBP, BBP, and DEHP, respectively, in 168h. A first-order kinetic model explained - the biodegradation progression, while the half-life of PAE degradation ranged from 12.8 to 29.8 h. Genera distribution of the SSB-consortium was determined by bacterial meta-taxonomic analysis. Serratia, Methylobacillus, Acrhomobacter, and Pseudomonas were the predominant genera; however, the type of phthalate directly affected their distribution. Scanning electron microscopy analysis showed that high concentrations (1000 mg L-1) of
phthalates induced morphological alterations in the bacterial SSB-consortium. The metabolite profiling showed that DEP, DBP, BBP, and DEHP could be fully metabolized through the de-esterification and β-oxidation pathways. Therefore, the SSB-consortium can be considered a potential candidate for bioremediation of complex phthalate-contaminated water resources.