Microbial Degradation of Petroleum Hydrocarbons and PCBs

石油烃和多氯联苯的微生物降解

• 批准号: 6742925
• 负责人: HAROLD D MAY
• 金额: $ 21.12万
• 依托单位: MEDICAL UNIVERSITY OF SOUTH CAROLINA
• 依托单位国家: 美国
• 财政年份: 2003
• 资助国家: 美国
• 起止时间: 2003-09-30 至 2005-07-31
• 项目状态: 已结题
• 来源: https://reporter.nih.gov/project-details/6742925
• 关键词: anaerobiosis; biotransformation; chlorination; electron transport; environmental contamination; gas chromatography mass spectrometry; halobiphenyl /halotriphenyl compound; microorganism population study; petroleum oil; polymerase chain reaction; soil microbiology; sulfates; water microbiology

Polychlorinated biphenyls (PCBs) and petroleum hydrocarbons (PHs) frequently co-contaminate aquatic sediments found at Superfund sites. Components of these complex and toxic mixtures bioaccumulate in the food chain eventually threatening human health. Microbial degradation of PCBs and PHs is often slow or inhibited by environmental conditions or the contaminants themselves. In fact, the co-contaminating PHs sorb PCBs leaving them unavailable for microbial dechlorination, a critical step in the degradation and detoxification of PCBs. The goal of the proposed research is to promote PCB dechlorination by first enhancing PH biodegradation. The Underlying Operative Hypothesis of this proposal is that oxidative metabolism performed by anaerobic microorganisms will catalyze enhanced degradation of petroleum, which will result in greater bioavailability of co-contaminating PCBs for reductive dechlorination. Aerobic biodegradation of PHs would require the introduction of oxygen, which would inhibit the oxygen sensitive PCB dechlorinating bacteria. That is why this investigation is focused on the anaerobic biodegradation of the PHs. The Specific Aims for the research are driven by the following hypotheses: 1) sulfate reduction as the terminal electron accepting process (TEAP) for PH degradation will result in enhanced microbial PCB dechlorination, and 2) microbial electrode reduction as the TEAP for PH degradation will result in enhanced microbial PCB dechlorination. Sulfate can serve as a terminal electron acceptor for the anaerobic oxidation of petroleum. Microbial electrode reduction is a new and promising method that can be coupled to the degradation of organic matter and does not require the active addition of a terminal electron acceptor such as oxygen or sulfate. The PIs intend to use innovative comprehensive two-dimensional gas chromatography (GCxGC/MS) to examine the complex mixtures of PCBs and PHs. This method enables researchers to analyze components of petroleum previously not resolvable. The microbial communities will be examined with recently developed PCR based molecular technologies. This study will be the first comprehensive investigation on the anaerobic degradation of PCBs and petroleum coupled to sulfate or novel electrode reduction. It is predicted that this innovative research will lead to the development of new technologies for the co-bioremediation of PCBs and petroleum.

多氯联苯 (PCB) 和石油碳氢化合物 (PH) 经常共同污染超级基金所在地的水生沉积物。这些复杂且有毒的混合物的成分在食物链中生物累积，最终威胁人类健康。 PCB 和 PH 的微生物降解通常很慢，或者受到环境条件或污染物本身的抑制。事实上，共同污染的 PH 会吸附 PCB，使其无法用于微生物脱氯，而微生物脱氯是 PCB 降解和解毒的关键步骤。本研究的目标是首先通过增强 PH 生物降解来促进 PCB 脱氯。该提案的基本假设是厌氧微生物进行的氧化代谢将催化石油的增强降解，这将导致共污染的多氯联苯用于还原脱氯的生物利用度更高。 PH 的需氧生物降解需要引入氧气，这会抑制对氧敏感的 PCB 脱氯细菌。这就是为什么本次研究重点关注 PH 的厌氧生物降解。该研究的具体目标由以下假设驱动：1) 硫酸盐还原作为 PH 降解的末端电子接受过程 (TEAP) 将导致增强的微生物 PCB 脱氯，2) 微生物电极还原作为 PH 降解的 TEAP 将导致增强的微生物 PCB 脱氯。硫酸盐可以作为石油厌氧氧化的末端电子受体。微生物电极还原是一种新的、有前途的方法，可以与 降解有机物，不需要主动添加末端电子受体，例如氧或硫酸盐。 PI 打算使用创新的综合二维气相色谱 (GCxGC/MS) 来检测 PCB 和 PH 的复杂混合物。这种方法使研究人员能够分析以前无法解析的石油成分。将使用最近开发的基于 PCR 的分子技术来检查微生物群落。这项研究将是首次对多氯联苯和石油的厌氧降解与硫酸盐或新型电极还原相结合的综合研究。预计这项创新研究将促进多氯联苯和石油联合生物修复新技术的发展。