间歇共基质调控厌氧共代谢分解难降解有机物的作用机制

The environmental hazards of refractory organic pollutants have aroused extensive attention in the world. As the important metabolism of anaerobic microorganisms, cometabolism has great development potential for the pollutant control, but the competitive inhibition between the growth substrate and refractory organic matter become the bottleneck of cometabolic regulation. Anaerobic cometabolism in the oligotrophic status provides a new idea to break through the bottleneck, but so far the regulation measures and mechanism of anaerobic cometabolism for the changes of nutritional status are unclear. The project regards the anaerobic cometabolism of pentachlorophenol as the research object, adopts the regulation method of intermittent cosubstrate, studies the characteristics of nutritional status and the degradation of refractory organic matter under the condition of intermittent cosubstrate, analyzes the cosubstrate utilization pattern of anaerobic microorganisms under different nutritional status, explores the effect of the changes of substrate utilization pattern on the metabolic pathways of refractory organic matter and the physiological characteristics of anaerobic microorganisms, clears the key factors and the regulation mechanism of intermittent cosubstrate in anaerobic cometabolic degradation of refractory organic matter. The project aims to provide a theoretical basis for the process control of anaerobic cometabolism and has practical value in expanding the scope of application of the cometabolism.

难降解有机污染物造成的环境危害问题已经在世界范围内引起了广泛关注。共代谢作为厌氧微生物的重要代谢机制在难降解有机污染物治理中具有巨大的发展潜力，但是生长基质和难降解有机物之间的竞争抑制成为共代谢调控的瓶颈。贫营养状态下厌氧微生物的共代谢作用为突破该瓶颈提供了新的思路，然而迄今为止营养状态转变过程中厌氧共代谢的调控措施及影响机制尚不清楚。本项目以难降解有机物-五氯酚的厌氧共代谢过程为对象，采用间歇共基质的调控方法，研究间歇共基质条件下营养状态的转变特征和难降解有机物的降解规律，分析不同营养状态下厌氧微生物的共基质利用模式，探讨共基质利用模式的转变对难降解有机物代谢途径和厌氧微生物生理特性的影响，明确间歇共基质调控厌氧共代谢分解难降解有机物的关键因子及作用机制。本项目旨在为厌氧共代谢的过程控制提供理论依据，对拓展共代谢的应用范围具有实用价值。

难降解有机污染物造成的环境危害问题已经在世界范围内引起了广泛关注。共代谢作为厌氧微生物的重要代谢机制在难降解有机污染物治理中具有巨大的发展潜力，但是生长基质和难降解有机物之间的竞争抑制成为共代谢调控的瓶颈。本项目以酚类污染物为目标，研究间歇共基质调控厌氧共代谢酚类化合物的效能，系统考察了一次性、等梯度和降梯度基质投加模式下五氯酚的降解规律，揭示了不同投加方式下乙酸钠的投加量对五氯苯酚降解效能和代谢途径，明确了最佳的乙酸钠投加方式和投加量。等梯度和降梯度乙酸钠投加方式不但能节省基质消耗，而且能够实现较高的五氯酚降解速率，并指出乙酸钠投加方式对于五氯酚代谢途径并没有显著的影响。研究了零价铁对间歇共基质体系下胞内外多糖含量、电子传递体系活性和菌群结构的变化，构建了零价铁强化厌氧降解五氯酚的反应体系。利用修正的数学模型实现了活性炭吸附多种混合酚的动力学表征，提出了分配系数用于描述不同酚类污染物竞争吸附关系。研究粉末活性炭投加和低氧曝气技术处理受酚冲击的活性炭厌氧膨胀床反应器，其中低氧曝气技术有助于缓解酚类对厌氧菌的抑制效果，并促进厌氧菌代谢能力的恢复。本项目成果为水环境中难降解酚类污染物厌氧处理提供了理论依据，也对相关酚类污染物的治理具有重要的借鉴意义。