石油污染土壤的微生物修复研究进展

随着石油工业的发展,石油污染土壤的问题变得日益严重,是目前世界各国重点关注、亟待解决的环境问题之一。微生物修复技术因其具有成本低、效率高、无二次污染等优点而被广泛应用于石油污染土壤的修复治理,主要包括生物培养、生物通风、固定化微生物技术。本文主要阐述了微生物修复石油污染土壤的修复方法及影响因素的研究进展,并对微生物修复技术的研究重点和发展趋势进行了合理的展望,以期为进一步研究提供参考。     

生物催化在环保中的应用进展

对生物催化剂在环境保护中的应用进行了阐述。具体描述了生物除污和生物产能两个方面。其中前者包括微生物的生物除污和酶生物除污,后者包括生产生物柴油、生物乙醇、生物氢和生物燃料电池。     

生物催化在环保中的应用进展

主要对生物催化剂在环境保护中的应用进行了阐述。具体描述了生物除污和生物产能2个方面。其中,前者包括微生物的除污和酶生物除污,后者包括生物柴油、生物乙醇、生物氢和生物燃料电池的生产。     

重金属污染的生物修复研究进展

目前,对重金属污染土壤进行生物修复已成为一个世界性的环境问题,引起了人们的高度关注。本文对重金属污染土壤修复技术的进展情况作了简要介绍和述评,重点介绍了植物修复技术和微生物修复技术,为土壤重金属污染的生物修复提供参考。     

利用生物炭负载微生物修复某搬迁制药厂污染土壤的研究

微生物和生物炭通过协同作用可实现有机污染土壤的低碳、绿色修复。采用浸渍吸附法将强溶磷功能细菌(Enterobacter sp.)负载于生物炭,制备了基于固定化微生物炭的土壤改良剂,通过实验室小试实验和场地中试实验,研究验证了炭基固定化微生物技术生物强化修复某搬迁药厂土壤的效果。结果表明,施加溶磷菌、生物炭以及基于固定化微生物炭的土壤改良剂均能不同程度地改善土壤理化性质,改善污染土壤细菌的群落结构,从而促进土壤中特征污染物的降解。其中炭基固定化微生物技术的修复效果最好,污染场地土壤中污染物浓度减少50%以上。该研究结果可为场地复合污染土壤修复提供理论依据和技术支持。     

农田重金属阻控的微生物修复技术研究进展

随着经济的快速发展,农田土壤重金属污染形势严峻。对农田重金属污染阻控技术的开发和应用已成为当前研究的主要内容。由于微生物修复具有高效、安全、成本低、无二次污染等诸多优点,从而成为近年来主要的土壤重金属污染修复方法,因此微生物修复技术在阻控重金属污染农田土壤方面有着广阔的发展前景。本文概述了微生物修复重金属污染农田土壤的概念和方法,利用微生物降解、吸附、转化等作用发展的微生物修复技术,在生物刺激、生物强化、固定化微生物等方面进行综述,为后续研究重金属污染农田土壤提供了思路与参考。     

土壤重金属污染的联合生物修复技术研究

随着石油、矿产的大量开采,土壤重金属污染日益严重,目前,我国耕地土壤污染程度已经严重危害到了农作物质量,甚至危害人体健康。本文对土壤微生物参与的土壤重金属污染的联合生物修复技术进行综述,并对土壤微生物在联合生物修复中的应用前景进行了展望,以期为重金属污染的生物修复研究提供新的思路。     

铀污染土壤生物修复的研究进展

放射性核素铀及其衰变产物引起的土壤环境污染是一个全球性的环境问题,采用合理的技术手段修复铀污染土壤具有重要的意义。生物修复具有高效、安全、廉价和对环境友好等特点,被称为环境友好替代技术。本文简要介绍了土壤铀污染的主要来源,综述了铀污染土壤生物修复的最新研究进展,包括铀污染土壤植物修复、微生物修复和植物联合微生物修复,最后对该领域未来的发展方向提出了建议。     

分子生物学技术在土壤生物修复中的应用及展望

综述了分子生物学技术包括环境微生物群落降解基因分析、16S rRNA序列分析技术以及荧光原位杂交技术在生物修复技术中跟踪污染土壤中降解微生物行为、监测降解基因和微生物群落变化,揭示了其中的分子机制的应用现状,对各项技术应用中需要注意的问题进行了讨论并对其发展前景进行了展望。     

微生物法修复重金属污染土壤的应用及展望

微生物法是土壤污染生物修复技术的重要组成部分,尤其应用于重金属污染土壤的修复,具有良好的发展前景。文章介绍了微生物对重金属污染土壤的修复机理及修复技术现状,综述了微生物-植物联合修复、微生物法-化学法联用技术的研究进展,最后指出今后的研究方向和发展趋势,为微生物法修复重金属污染土壤的理论研究及应用提供参考。     

Utilization of genetically engineered microorganisms (GEMs) for bioremediation

The wide metabolic and physiological versatility of microorganisms can be used to degrade many pollutants. Bioremediation is the technological process whereby biological systems are harnessed to effect the clean‐up of environmental pollutants. Nowadays, microbial systems are employed in bioremediation programmes, generally in the treatment of soils and waters contaminated with organic pollutants. There are instances where natural populations are not suitable for use in the remediation of polluted sites and therefore the utilization of genetically engineered microorganisms (GEMs) is being considered for in‐situ bioremediation of contaminated ecosystems. The deliberate release of GEMs into the environment is a subject of considerable public concern. The potential risks associated with the release of GEMs into the environment has led to the construction of biological containment systems by which bacteria are killed in a controlled suicide process. Active biological containment systems usually consist of two different components, a killing element designed to induce cell death and a control element which modulates the expression of the killing function. © 1999 Society of Chemical Industry     

石油烃污染场地低温修复机制研究进展

生物修复一直是石油烃污染场地修复技术的研究热点,已经取得了很多实验和理论认知。但是,现有研究主要集中在中高温环境下,而在实地修复中,生物修复往往要跨越中低温期,此时,无论是土著还是外源微生物的生理特性都将发生改变;由于细胞活力低,这一时期经常在修复过程中被忽视,或是采用缺乏针对性的常规工艺而事倍功半。本文围绕低温生物修复技术,概述了低温石油烃降解微生物的研究现状,重点介绍了长链烷烃、苯及其同系物、多环芳烃三大类典型石油烃的低温代谢机制和主要代谢途径;在此基础上,从脂肪酸的组成、蛋白的低温表达、特殊蛋白的合成以及酶的结构适应性等4个方面,进一步剖析了低温环境下细胞生理生化特性的微观变化,这种低温微生物独有的适冷机制决定了其特有的低温降解特性,并成为低温修复的核心。分析表明,低温期生物修复应该得到足够重视：一方面,充分而合理地利用漫长的低温期,针对性实施低温期受控修复,提高营养盐利用率,可以有效提高生物修复效率;另一方面,深入研究细胞低温代谢和适冷机制有助于指导低温修复手段的实施,将成为切实可行的发展方向。     

鼠李糖脂在土壤污染修复中的应用研究进展

介绍了生物表面活性剂鼠李糖脂在土壤重金属污染的修复作用及对土壤中原油、多氯联苯、多环芳烃等污染物的降解作用,并且廉价、无毒、可生物降解,具有广阔的应用前景。     

除草剂在土壤中的微生物降解及污染土壤的生物修复

除草剂施入土壤中后，一般通过物理、化学与生物学过程而消失。微生物降解是除草剂在土壤中消失的最重要因素。评述了除草剂在土壤中的微生物降解及主要类型除草剂的降解特点，提出了长残留除草剂污染土壤的生物修复技术。     

污染土壤的生物修复综述

土壤是人类赖以生存的主要自然资源之一,是人类生态环境的重要组成部分。我国土壤污染总体形势相当严峻。文章介绍了土壤污染的基本情况,主要阐述了污染土壤的生物修复,并总结了存在的一些问题。     

Microbial metabolism of xenobiotics: Fundamental and applied research

The ability of microorganisms to metabolise xenobiotic compounds has received much attention due to the environmental persistence and toxicity of these chemicals. The microbial degradation of xenobiotics is seen as a cost effective method of removing these pollutants from the environment by a process now known as bioremediation. Microbial treatment of industrial effluents is also possible. Fundamental work has revealed that a wide variety of microorganisms are capable of degrading an equally wide range of organic pollutants. Pure and mixed cultures of microorganisms have been studied and degradation is observed under both aerobic and anaerobic conditions. Breakdown products have been found during work on the degradative pathways involved and toxicological assessments using bacteria and higher organisms (fish, plants) have been used to determine the toxicity of these intermediates. Many of the degradative genes responsible for xenobiotic metabolism are present on plasmids, transposons or are grouped in clusters on chromosomes. This provides clues to the evolution of degradative pathways and makes the task of genetic manipulation easier such that new microbial strains capable of efficiently degrading pollutants can be developed. Several enzymes involved in xenobiotic metabolism have been isolated and factors affecting their activity investigated. Genetically manipulated strains or naturally isolated organisms may be used in the treatment of industrial wastes or as inocula to enhance degradation in the environment. Environmental factors, including pH, temperature, bioavailability, nutrient supply and oxygen availability have been shown to affect xenobiotic biodegradation. These factors must be optimised to obtain a satisfactory microbial treatment process. Using information gained from fundamental research, bioremediation technology has been used to detoxify different contaminated environments and the results of field studies are very encouraging.     

Effects of Secondary Plant Metabolites on Microbial Populations: Changes in Community Structure and Metabolic Activity in Contaminated Environments

Secondary plant metabolites (SPMEs) play an important role in plant survival in the environment and serve to establish ecological relationships between plants and other organisms. Communication between plants and microorganisms via SPMEs contained in root exudates or derived from litter decomposition is an example of this phenomenon. In this review, the general aspects of rhizodeposition together with the significance of terpenes and phenolic compounds are discussed in detail. We focus specifically on the effect of SPMEs on microbial community structure and metabolic activity in environments contaminated by polychlorinated biphenyls (PCBs) and polyaromatic hydrocarbons (PAHs). Furthermore, a section is devoted to a complex effect of plants and/or their metabolites contained in litter on bioremediation of contaminated sites. New insights are introduced from a study evaluating the effects of SPMEs derived during decomposition of grapefruit peel, lemon peel, and pears on bacterial communities and their ability to degrade PCBs in a long-term contaminated soil. The presented review supports the “secondary compound hypothesis” and demonstrates the potential of SPMEs for increasing the effectiveness of bioremediation processes.     

Development of an Autochthonous Microbial Consortium for Enhanced Bioremediation of PAH-Contaminated Soil

The main objectives of this study were to isolate bacteria from soil chronically contaminated with polycyclic aromatic hydrocarbons (PAHs), develop an autochthonous microbial consortium, and evaluate its ability to degrade PAHs in their native contaminated soil. Strains with the best bioremediation potential were selected during the multi-stage isolation process. Moreover, to choose bacteria with the highest bioremediation potential, the presence of PAH-degrading genes (pahE) was confirmed and the following tests were performed: tolerance to heavy metals, antagonistic behavior, phytotoxicity, and antimicrobial susceptibility. In vitro degradation of hydrocarbons led to the reduction of the total PAH content by 93.5% after the first day of incubation and by 99.22% after the eighth day. Bioremediation experiment conducted in situ in the contaminated area resulted in the average reduction of the total PAH concentration by 33.3% after 5 months and by over 72% after 13 months, compared to the concentration recorded before the intervention. Therefore, this study implicates that the development of an autochthonous microbial consortium isolated from long-term PAH-contaminated soil has the potential to enhance the bioremediation process.     

Sorption-Desorption of Pyrene for Colombia and New Mexico Soils

The adsorption and availability of polycyclic aromatic hydrocarbons (PAHs) in the environment is an important factor to be considered for potential bioremediation processes. If desorption of the organic occurs, it could imply that remediation technologies such as microbial degradation may be feasible for PAH contaminated soils. Conversely no, or partial, desorption would indicate that the components may persist in the environment due to their decreased bioavailability. The sorption-desorption of pyrene in conjunction with two different soils was studied to determine the feasibility of bioremediation as an effective treatment. The measured distribution coefficient (K _d ) for the Colombia and New Mexico soils using a 4:40 soil:liquid ratio was 1956 and 526 L/kg, respectively. When the soil:liquid ratio was reduced to 1:40, the K _d values were 4294 L/Kg for the Colombia, and 1141 L/Kg for the New Mexico soil.