中文摘要：

考察了Paracoccusversutus菌株GWl的醌呼吸特性及4种结构相似的醌类介体（AQS，α-AQS，AQDS和1，5-AQDS）催化强化Paracoccusversutus菌株GWl的反硝化过程．结果表明，Paracoccusversutu$菌株GWl能利用醌类介体作为其电子传递链中的电子受体进行呼吸，使醌类介体还原为相应的氢醌形式；在35℃条件下，采用间歇试验法，4种介体浓度均为0．24mmol·L-1时，可分别提高硝酸盐氮降解速率1．14-1．63倍、总氮去除速率1．12-2．02倍，其从大到小顺序为：AQDS〉1，5-AQDS〉AQS〉α-AQS；介体可降低Paracoccusversutus菌株GWl硝酸盐降解过程中氧化还原电位约33-75mV；介体催化强化硝酸盐降解过程中pH变化趋势与空白对照组类似，最终pH稳定在9．0左右；在0—0．32mmol·L。AQDS浓度范围内，体系硝酸盐氮降解零级反应速率常数K与介体的浓度CAQDS呈线性关系．本研究为解决生物脱氮技术存在降解速率低的问题提供了有效途径．

英文摘要：

The quinone respiration process of Paracoccus versutus strain GW1 was characterized and the effects of the four redox mediators on the denitrification process were studied. The experiment results suggested that quinones were utilized by Paracoccus versutus strain GW1 as electron acceptors in the respiratory chain and reduced to hydroquinone. Batch experiments were carried out to investigate the biocatalyst effect of redox mediators as catalyst on the denitrification process at 35~C. All four redox mediators tested were able to enhance the nitrate removal efficiency and the denitrification efficiency by 1.14-1.63 fold and 1. 12-2.02 fold, respectively. The accelerating effect from high to low was AQDS 〉 1,5-AQDS 〉 AQS 〉α-AQS. In the presence of redox mediators, the stabilized ORP values in the nitrate decomposition process were reduced by 33-75 mV. The pH variations in denitrification with redox mediators showed similar tendency to that of the conventional nitrate removal process. In the concentration range of 0-0.32 mmol. L-1, AQDS had the best accelerating effect and a linear correlation was found for the denitrification rate K and the AQDS concentration CAQDS. This study indicated that the application of redox mediators significantly improved the denitrification process by enhancing the decomoosition rate.