Agro-Environmental Protection Institute, Ministry of Agriculture, MOA Key Laboratory of Original Agro-Environmental Pollution Prevention and Control, No. 31 Fukang Road, Nankai District, Tianjin 300191, China.
Ministry of Education Key Laboratory of Pollution Processes and Environmental Criteria, College of Environmental Science and Engineering, Nankai University, No. 38 Tongyan Road, Jinnan District, Tianjin 300350, China.
J Hazard Mater. 2018 Feb 15;344:23-32. doi: 10.1016/j.jhazmat.2017.09.050. Epub 2017 Oct 7.
Soil contaminated by aged petroleum hydrocarbons is faced with scarcity of electron acceptors, low activity of functional microbes and inefficient electron transfer, which hinder the bioremediation application. The soil microbial fuel cell (MFC) simultaneously solves these problems with bioelectricity production. In this study, five types of surfactants were introduced to enhance the bioavailability of aged petroleum hydrocarbon in soils. The ampholytic surfactant (lecithos) was optimal due to the highest bioelectricity generation (0.321Cdg) and promoted hydrocarbon degradation (328%), while the nonionic (glyceryl monostearate) and cationic (cetyltrimethylammonium bromide) surfactants were inefficient. The surfactants induced a special microbial enrichment affiliated with Proteobacteria, Firmicutes, Bacteroidetes, Actinobacteria, Chloroflexi, Planctomycetes and Acidobacteria (93%-99% of total) in soil MFCs. The anionic surfactant (sodium dodecyl sulfate) exhibited the strongest selectivity, and α-proteobacteria and γ-proteobacteria abundances decreased while Clostridia increased, much like the result obtained with the biosurfactant β-cyclodextrin. Furthermore, Bacillus abundance was increased in connected soil MFCs, except addition of lecithos in which Clostridium increased to 14.88% from 3.61% in the control. The high correlations among Bacillus, Phenylobacterium, Solibacillus (0.9162-0.9577) and among Alcaligenes, Dysgonomonas, Sedimentibacter (0.9538-0.9966) indicated a metabolic network of microorganisms in the soil bioelectrochemical remediation system.
受老化石油烃污染的土壤面临着电子受体稀缺、功能微生物活性低和电子传递效率低等问题，这阻碍了生物修复的应用。土壤微生物燃料电池（MFC）通过生物电能的产生同时解决了这些问题。在本研究中，引入了五种表面活性剂来提高土壤中老化石油烃的生物利用度。两性表面活性剂（卵磷脂）由于产生的生物电能（0.321Cdg）最高和促进烃类降解（328%）最高，是最有效的，而非离子（甘油单硬脂酸酯）和阳离子（十六烷基三甲基溴化铵）表面活性剂则效果不佳。表面活性剂在土壤 MFC 中诱导了一种特殊的微生物富集，与变形菌门、厚壁菌门、拟杆菌门、放线菌门、绿弯菌门、浮霉菌门和酸杆菌门（占总数的 93%-99%）有关。阴离子表面活性剂（十二烷基硫酸钠）表现出最强的选择性，α-变形菌门和γ-变形菌门的丰度降低，而梭菌门的丰度增加，这与生物表面活性剂β-环糊精的结果非常相似。此外，在连接的土壤 MFC 中增加了芽孢杆菌的丰度，除了添加卵磷脂外，芽孢杆菌的丰度从对照的 3.61%增加到 14.88%。芽孢杆菌、苯基杆菌、Solibacillus（0.9162-0.9577）之间以及 Alcaligenes、Dysgonomonas、Sedimentibacter（0.9538-0.9966）之间的高相关性表明了土壤生物电化学修复系统中微生物的代谢网络。
