Key Laboratory of Marine Chemistry Theory and Technology, Ministry of Education, Ocean University of China, 238 Songling Road, Qingdao 266100, Shandong, China.
College of Chemistry & Chemical Engineering, Ocean University of China, Qingdao 266100, China.
Environ Sci Process Impacts. 2015 Dec;17(12):2022-33. doi: 10.1039/c5em00318k.
The efficiencies of free and immobilized microbial consortia in the degradation of different types of petroleum hydrocarbons were investigated. In this study, the biodegradation rates of naphthalene, phenanthrene, pyrene and crude oil reached about 80%, 30%, 56% and 48% under the optimum environmental conditions of free microbial consortia after 7 d. We evaluated five unique co-metabolic substances with petroleum hydrocarbons, α-lactose was the best co-metabolic substance among glucose, α-lactose, soluble starch, yeast powder and urea. The orthogonal biodegradation analysis results showed that semi-coke was the best immobilized carrier followed by walnut shell and activated carbon. Meanwhile, the significance of various factors that contribute to the biodegradation of semi-coke immobilized microbial consortia followed the order of: α-lactose > semi-coke > sodium alginate > CaCl2. Moreover, the degradation rate of the immobilized microbial consortium (47%) was higher than that of a free microbial consortium (26%) under environmental conditions such as the crude oil concentration of 3 g L(-1), NaCl concentration of 20 g L(-1), pH at 7.2-7.4 and temperature of 25 °C after 5 d. SEM and FTIR analyses revealed that the structure of semi-coke became more porous and easily adhered to the microbial consortium; the functional groups (e.g., hydroxy and phosphate) were identified in the microbial consortium and were changed by immobilization. This study demonstrated that the ability of microbial adaptation to the environment can be improved by immobilization which expands the application fields of microbial remediation.
考察了游离和固定化微生物群落对不同类型石油烃降解的效率。在本研究中，游离微生物群落的最佳环境条件下，萘、菲、芘和原油的生物降解率在 7d 后分别达到约 80%、30%、56%和 48%。我们评估了 5 种具有石油烃共代谢作用的独特物质，其中α-乳糖是葡萄糖、α-乳糖、可溶性淀粉、酵母粉和尿素中最好的共代谢物质。正交生物降解分析结果表明，半焦是最好的固定化载体，其次是核桃壳和活性炭。同时，对半焦固定化微生物群落生物降解的各种因素的重要性顺序为：α-乳糖>半焦>海藻酸钠>CaCl2。此外，在环境条件下，固定化微生物群落（47%）的降解率高于游离微生物群落（26%），环境条件为原油浓度 3g/L(-1)、NaCl 浓度 20g/L(-1)、pH7.2-7.4 和 25°C 下 5d。SEM 和 FTIR 分析表明，半焦的结构变得更加多孔，更容易附着在微生物群落上；微生物群落中鉴定出了功能基团（如羟基和磷酸盐），并通过固定化发生了变化。本研究表明，通过固定化可以提高微生物对环境的适应能力，从而扩大微生物修复的应用领域。
