摘要
多环芳烃(PAHs)是普遍存在于环境中具有强烈毒性、致突变性和致癌性的难降解有机物,可造成严重的环境污染。由于低水溶性而导致的低生物可利用率是限制PAHs微生物降解的主要因素。生物表面活性剂鼠李糖脂由于在形成胶束后能够大幅提高PAHs的表观溶解度,且毒性低、无二次污染,因而在PAHs微生物降解的研究中得到广泛关注。目前关于鼠李糖脂强化PAHs微生物降解的研究主要集中于其强化效果,而对其强化机制的研究仍不够深入。该文基于鼠李糖脂的性质及铜绿假单胞菌(Pseudomonas aeruginosa)的鼠李糖脂生物合成及调控,从鼠李糖脂提高PAHs溶解度、强化胶束传质、提高细胞表面疏水性、降低细胞表面Zeta电位、提高细胞膜通透性等方面综述其在强化PAHs微生物降解机制方面的最新研究进展,并总结了温度、pH、浓度和离子强度等环境因素对强化效果的影响。在此基础上,提出未来需要进一步探索鼠李糖脂生物可降解性与强化降解效果之间的平衡关系,明确pH影响PAHs溶解度的机理,并从基因、转录、蛋白和代谢水平对鼠李糖脂作用前后降解菌内参与调控菌体细胞表面疏水性(CSH)和膜通透性的相关基因的表达差异进行分析,阐释相关强化机制的深层机理,寻求降解过程中菌体最佳CSH和膜通透性,找寻使降解菌达到降解最佳状态的基因调控手段,为进一步深入研究鼠李糖脂的强化机制提供理论支撑。
Polycyclic aromatic hydrocarbons (PAHs) are refractory organic compounds that are ubiquitous in the environment and have strong toxicity, mutagenicity and carcinogenicity, which can cause serious environmental pollution. Low bioavailability due to low water solubility is the main factor limiting the biodegradation of PAHs. The biosurfactant, rhamnolipids, has attracted extensive attention in the study of PAHs biodegradation because they can greatly improve the apparent solubility of PAHs after the formation of micelles, and have low toxicity and no secondary pollution. At present, research on the enhancement mechanism is still not in-depth.Based on the properties of rhamnolipids and biosynthesis and regulation of rhamnolipids by Pseudomonas aeruginosa, this article reviewed the latest research progress of applying rhamnolipids to enhancing the microbial degradation mechanism of PAHs biodegradation, focusing on the role of rhamnolipids in increasing the solubility of PAHs, enhancing micellar mass transfer, improving cell surface hydrophobicity, reducing cell surface zeta potential, and improving cell membrane permeability. Moreover, the effects of environmental factors on the enhancement effects, such as temperature, pH, concentration, and ionic strength were summarized. On this basis, it is necessary for future research to explore the balance between the biodegradability of rhamnolipids and the biodegradation effect, and clarify the mechanism of pH affecting the solubility of PAHs. From the levels of gene, transcription, protein, and metabolism,it is necessary to analyze different gene expressions involved in regulating bacterial cell surface hydrophobicity (CSH) and membrane permeability in degrading bacteria before and after the action of rhamnolipids to explain the deeper relevant enhancement mechanism,seek the best CSH and membrane permeability of the bacteria in the degradation process, and look for the gene regulation methods to make the degrading bacteria reach the best state of degradation, so as to provi
作者
吴洁婷
赵若帆
包红旭
张营
赵磊
许琪
陈忠林
徐丽丽
张驰
许海萍
马放
WU Jieting;ZHAO Ruofan;BAO Hongxu;ZHANG Ying;ZHAO Lei;XU Qi;CHEN Zhonglin;XU Lili;ZHANG Chi;XU Haiping;MA Fang(College of environment,Liaoning University,Shenyang 110036,P.R.China;State Key Laboratory of Urban Water Resource and Environment,Harbin Institute of Technology,Harbin 150090,P.R.China;Yingkou Dashiqiao Ecological Environment Bureau,Yingkou 115100,P.R.China)
出处
《生态环境学报》
CSCD
北大核心
2022年第1期205-214,共10页
Ecology and Environmental Sciences
基金
辽宁省教育厅科学研究经费项目(LQN201908)
国家自然科学基金项目(51608246)。
关键词
鼠李糖脂
多环芳烃
强化
微生物修复
细胞表面疏水性
ZETA电位
细胞膜通透性
rhamnolipids
polycyclic aromatic hydrocarbons
strengthening
microbial remediation
cell surface hydrophobicity
zeta potential
membrane permeability
