磷化氢生物净化体系及抑制作用机理

在PH₃生物净化体系中添加呼吸链电子传递抑制剂，对比分析微生物生长代谢、磷的迁移转化、活性氧（ROS）产生及氧化酶活性等变化规律.当鱼藤酮或抗霉素A分别添加至R1、R2PH₃生物反应器后，其微生物体O₂^-·含量在运行时间14~17d期间的平均值分别上升至0.68，0.96mmol/g，明显高于空白对照组R0反应器.除自由基O₂^-·外，另一类型的活性氧HO·也存在于PH₃净化系统中；受累积的活性氧影响，生物体内丙二醛（MDA）含量处于较高水平，PH₃净化效率通常不超过75%，添加抑制剂的R1与R2反应体系在15~17d期间PH₃平均去除率分别下降至65.1%、59.5%.pH值、ROS含量以及氧化酶活性等因素均明显影响PH₃生物净化效果，当Fe³⁺、Cu²⁺、Mg²⁺等金属阳离子迁移转运至微生物体内时，超氧化物歧化酶（SOD）与过氧化氢酶（CATase）活性得以不同程度的增强，可缓解活性物质O₂^-·或HO·导致的氧化胁迫作用，PH₃净化效能得以适度提升.

Inhibition mechanism of phosphine biological purification system

Two electron transport inhibitors (rotenone and anti-mycin A) were introduced to phosphine bio-purification systems, then comparative experiments were conducted to investigate the variations of the microbial growth and metabolisms, phosphorus transport and transformation, the production of reactive oxygen species (ROS), and oxidase activities. When rotenone and anti-mycin A were respectively added to R1 and R2 bioreactors, the average O₂^-· content in these two systems increased to 0.68 and 0.96 mmol/g during the operation time of 14~17 days, which was significantly higher than control group (i.e. R0 reactor). Besides O₂^-·, another kind of reactive oxygen species, i.e. HO·, was also detected in bio-purification systems. In addition, due to the ROS accumulation, the malondialdehyde (MDA) content in microorganisms kept at a high level, caused the purification efficiency of phosphine less than 75%. The average phosphine removal efficiency in the R1 and R2 bioreactors decreased to 65.1% and 59.5% respectively, after 15~17 days operation. The factors, e.g., pH, ROS, and oxidase activity, had significant effects on phosphine biological purification. As metal cations such as Mg²⁺ and Cu²⁺ migrated into the microbial cells, the enzyme activities of superoxide dismutase and catalase were dramatically improved, which led to the alleviation of the oxidative stress derived from the reactive species such as O₂^-· and HO·. As the consequence, the purification efficacy of phosphine was improved moderately.