Microbial Degradation of Petroleum Hydrocarbons and PCBs

石油烃和多氯联苯的微生物降解

• 批准号: 6804945
• 负责人: HAROLD D MAY
• 金额: $ 15.63万
• 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 2006-07-31
• 项目状态: 已结题
• 来源: https://reporter.nih.gov/project-details/6804945
• 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（PHS）经常在超级基金部位发现的水生沉积物。这些复杂和有毒混合物的成分在食物链中生物蓄积最终威胁到人类健康。 PCB和PHS的微生物降解通常会因环境​​条件或污染物本身而缓慢或抑制。实际上，共同接合PHS SORB PCB使它们无法用于微生物脱氯，这是PCBS降解和排毒的关键步骤。拟议的研究的目的是通过首先增强pH生物降解来促进PCB脱氯。该提案的基本手术假设是，厌氧微生物进行的氧化代谢将催化石油的降解，这将导致共启动PCB的生物利用度更高，以减少氯化。 PHS的有氧生物降解需要引入氧气，这将抑制氧气敏感的PCB脱氯细菌。这就是为什么这项研究集中在PHS的厌氧生物降解上的原因。该研究的具体目的是由以下假设驱动的：1）硫酸盐还原，因为末端电子接受过程（TEAP）的pH降解将导致微生物PCB脱氯的增强，而2）微生物电极还原，因为pH降解的TEAP将导致增强的微生物PCB PCB脱发。硫酸盐可以用作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且有前途的方法，可以耦合到 有机物的降解，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法（GCXGC/MS）检查PCB和PHS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的组件。将使用最近开发的基于PCR的分子技术检查微生物群落。这项研究将是对PCB和石油与硫酸盐或新型电极还原的厌氧降解的首次全面研究。据预测，这项创新的研究将导致开发用于PCB和石油共同修复的新技术。