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61.
人工湿地系统微生物去除污染物的研究进展 总被引:7,自引:1,他引:6
人工湿地污水处理系统具有净化效果显著、建设和运行费用低廉、管理简便等优点,近年来越来越受到人们的重视。人工湿地是利用介质、植物和微生物构成的复合系统来处理污水。微生物在人工湿地系统净化污水过程中发挥着重要作用。介绍了人工湿地系统中微生物去除污染物的研究进展,重点讨论了人工湿地对污染物和特殊有机污染物的去除以及系统基质中微生物的种群和活性等内容,并结合我国研究现状展望了该领域的研究前景。人工湿地系统微生物对污染物去除将成为人工湿地生态系统服务功能评价、人工湿地生态系统健康与稳定的诊断的重要组成部分。 相似文献
62.
聚合物驱采出水中聚丙烯酰胺的微生物联合降解作用研究 总被引:2,自引:0,他引:2
通过对2株细菌的培养降解实验研究聚丙烯酰胺(hydrolyzed polyacrylamide,HPAM)降解菌对水环境下聚丙烯酰胺的降解作用,讨论协同降解机理。2株降解聚丙烯酰胺的菌株假单胞菌CJ419、枯草芽孢杆菌FA16在初始30℃废水样品上培养,定期测量细菌生物量和HPAM降解率。培养30 d后CJ419和FA16对聚合物的降解率最大值分别达到30.4%和25%,而以1∶1比例的混合菌降解率最大值达到80.3%。对2株菌胞外各组分研究表明:混合菌降解HPAM的机理主要由胞外降解酶系水解聚合物侧链基团导致HPAM降解为小分子物质,同时生长过程中降解菌还会释放非蛋白还原性物质引发氧化反应共同参与HPAM降解。 相似文献
63.
通过对3,5-二硝基水杨酸(DNS)法测定还原糖含量各影响因素的筛选,优化确定了显色时间8 min,稳定时间10 min,最佳波长490 nm下进行吸光度测定的检测方法;分析分别以葡萄糖和麦芽糖作为外加碳源时,降解菌Pseudomonas putida B-31的生长情况和共代谢降解典型药物苯扎贝特(BZF)的过程。结果表明,降解菌只有在外加碳源的条件下才可正常生长,而且其在葡萄糖环境中生长得更好;拟合得到的葡萄糖、麦芽糖和BZF代谢动力学结果显示,葡萄糖对BZF去除的促进作用更为明显,同时从葡萄糖培养基中降解菌所提取的酶比活力要高于麦芽糖培养基,分析原因可能是葡萄糖所诱导的降解菌关键酶活力更强,而且还可能会产生不同的蛋白质点位。 相似文献
64.
大型蚤是一种国际公认的标准实验生物,广泛应用于污水、地表水等水质毒性检测。毒性水平较低的城市二级出水,对大型蚤往往无急性毒性效应,而具有慢性毒性效应,但慢性毒性检测周期过长,因此探索一种更灵敏的指标,实现快速检测,对于控制二级出水的水质风险具有重要意义。本研究考察了大型蚤在短期暴露于城市二级出水条件下,其体内乙酰胆碱酯酶、超氧化物歧化酶、过氧化氢酶、ATP酶、羧酸酯酶和碱性磷酸酯酶的酶活变化特征,从中筛选出对二级出水毒性响应灵敏的标志酶指标。实验结果表明,碱性磷酸酯酶、过氧化氢酶对二级出水毒性响应相对较灵敏,具有成为标志酶的潜力,研究结果为城市二级出水生物毒性评价方法优化提供新的思路。 相似文献
65.
66.
The dissipation of carbendazim and chloramphenicol alone and in combination and their effects on soil fungal:bacterial ratios and soil enzyme activities were investigated. The results revealed that carbendazim dissipation was little affected by chloramphenicol, whereas chloramphenicol dissipation was found to be retarded significantly by the presence of carbendazim. The inhibitory effect of carbendazim on the fungal:bacterial ratios was increased by the presence of chloramphenicol, and the inhibitory effect of chloramphenicol on neutral phosphatase was increased by the presence of carbendazim. Carbendazim increased soil catalase and urease activities, but this increase was partially diminished by the presence of chloramphenicol. Little interaction was observed between carbendazim and chloramphenicol with regard to their influence on soil invertase. The results obtained in this study suggest that combinations of fungicides and antibiotics may alter the compounds’ individual behaviors in soil and their effects on soil enzymes. 相似文献
67.
Cobalt is an essential element, but at high concentrations it is toxic. In addition to its well-known function as an integral part of cobalamin (vitamin B12), cobalt has recently been shown to be a mimetic of hypoxia and a stimulator of the production of reactive oxygen species. The present study investigated the responses of goldfish, Carassius auratus, to 96 h exposure to 50, 100 or 150 mg L−1 Co2+ in aquarium water (administered as CoCl2). The concentrations of cobalt in aquaria did not change during fish exposure. Exposure to cobalt resulted in increased levels of lipid peroxides in brain (a 111% increase after exposure to 150 mg L−1 Co2+) and liver (30-66% increases after exposure to 50-150 mg L−1 Co2+), whereas the content of protein carbonyls rose only in kidney (by 112%) after exposure to 150 mg L−1 cobalt. Low molecular mass thiols were depleted by 24-41% in brain in response to cobalt treatment. The activities of primary antioxidant enzymes, superoxide dismutase (SOD) and catalase, were substantially suppressed in brain and liver as a result of Co2+ exposure, whereas in kidney catalase activity was unchanged and SOD activity increased. The activities of glutathione-related enzymes, glutathione peroxidase and glutathione-S-transferase, did not change as a result of cobalt exposure, but glutathione reductase activity increased by ∼40% and ∼70% in brain and kidney, respectively. Taken together, these data show that exposure of fish to Co2+ ions results in the development of oxidative stress and the activation of defense systems in different goldfish tissues. 相似文献
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69.
Imidacloprid (IMI), a neonicotinoid insecticide, is widely used to control pests in agriculture. We investigated the changes in antioxidant enzyme activities, lipid peroxidation levels, biochemical effects, genotoxic effect, and immunotoxic effect of sublethal doses (0.25, 0.50, 0.75, and 1.00?µg) of IMI at different time periods (24, 48, 72, and 96?h) on a model organism, Galleria mellonella L. The results indicated that there were dose-dependent increases in both antioxidant enzyme activities (SOD and CAT) and MDA levels. Protein content was not affected by IMI at 24th and 48th, whereas it was decreased by the highest dose of IMI (1.00?µg) at 72nd and 96th h. Lipid and carbohydrate contents were reduced with increasing doses of IMI. Micronucleus frequency significantly increased in all IMI doses. All IMI doses caused a significant decrease in THC at 24th, 48th, and 72nd h. Our results can help to illustrate the effects of IMI in target organisms and indirectly may aid to discover potential risk of it on nontarget organisms. Future studies, at molecular levels, will be helpful in understanding the mechanism of action of IMI on these biomarkers. 相似文献
70.