【作者】 马文花；

【导师】 王关林；

【作者基本信息】 辽宁师范大学 ， 细胞生物学， 2009， 硕士

【摘要】 高盐医药废水种类很多,并且成分复杂,某些废水含有许多难以降解的杂环芳烃等有机物。目前研究表明杂环芳烃如喹啉及其衍生物具有致癌、致畸、致突变性,对自然界生物安全和人类健康构成巨大威胁,因而杂环芳烃等有机物降解菌的筛选一直是国内外微生物降解的一个重要方面。这些废水中不仅含高浓度有机污染物,还含大量的盐分(如Na⁺,Cl^-,Ca²⁺,Mg²⁺等离子),是废水处理领域中的技术难题,常规的生物法很难有效地处理该类废水。为了解决难降解有机废水中高盐含量对传统生物处理系统的抑制问题,本文以含有高浓度氯离子（大于30 000mg/L）的医药废水（COD浓度大于10 000mg/L）为研究基质筛选出既耐高盐又可以高效降解有机污染物的两株菌株,分别命名为HB1和HB2,根据菌株生理生化特性作初步鉴定。然后分别研究了两株菌的基础生物学特征及在不同环境因素的条件下降解主要成分为杂环芳烃的医药废水的能力;最后为了进一步提高COD去除率,紫外诱变处理耐盐菌HB2,将突变菌株UVHB2-1、UVHB2-2投加到制药废水中,同原出发菌株的投加作对比,考察紫外诱变对COD去除率的影响,并且筛选出COD去除率明显提高的优势突变菌。实验结果表明:（1）分离到两株耐盐菌株,初步鉴定分别为盐杆菌属和节杆菌属,在含有0.5-10%NaCl的液体基本培养基中生长良好,菌株HB1最适生长温度为20℃-30℃;菌株HB2最适生长温度为35℃-40℃;两菌株最适pH值都在7.5;（2）菌株降解医药废水COD的实验表明,废水初始COD、pH值、温度、接种量以及处理时间均对其降解能力有较大的影响。COD初始浓度为11 880mg/L,接种量为6mL,pH为7.5,盐浓度为5%,温度为35℃,培养时间为4天的条件下,HB2的COD去除率最高可达到39.9%;COD初始浓度为11 880mg/L,接种量为6mL,pH为7.5,盐浓度为5%,温度为30℃,培养时间为4天的条件下,HB1的COD去除率最高可达到34.7%。（3）经过紫外诱变处理筛选出一株优势突变菌UVHB2-1,处理医药废水的效果有明显提高,降解率可达68.2%,而且遗传性稳定,同时仍具有耐盐性能。更多还原

【Abstract】 There is many kinds of medical wastewater with complicated organic composition such as Heterocyclic aromatic which is difficult to be degraded.At present studies show that Heterocyclic aromatic and its derivative may be carcinogenicity,teratogenicity and mutagenicity,which is dangerous to nature and human.So it is important to screen Heterocyclic aromatic-degraded microbiology. Because there is also high salinity(ions such as Na⁺,Cl^-,Ca²⁺,Mg²⁺),it is difficult to be treated by conventional biochemical processes.To solve the problem of inhibitory effect of high salinity on traditional biological wastewater treatment system,the objective of this paper was to screen and use halophytic strains to treat medical wastewater.Firstly,salt-tolerant strains with high biodegradation capability were screened and identified primarily.Secondly,morphology,biochemical properties and removal efficiencies of medical wastewater with Heterocyclic aromatic by strains in different conditions were studied.One of salt-tolerant strains known as HB2 was treated by using the method of UV radiation in order to improve removal efficiencies. The main results are as follows:（1） Two novel NaCl-tolerant bacterial strains（HB1 and HB2） isolated and identified primarily as Halo-bacterium salinarium and Arthrobacter Conn and Dimmick.Results showed that bacterial strain HB1and HB2 could grow in the media contained 0.5-5%NaCl;And they grew well in the media with pH 7.5,the best temperature is20℃-30℃for HB1 and is 35℃-40℃for HB2;（2）Studies on COD of medical wastewater removal efficiencies of two strains show that some factors have influence in removal efficiencies:with primary concentration 11 880mg/L,salt concentration 5%and inoculation 6mL,COD removal efficiency was high up to about 39.9%when degradation time,pH,temperature were 4d,7.5,35℃for HB2;while the COD removal efficiency was about 34.7%when degradation time,pH,temperature were 4d,7.5,30℃for HB1.（3） HB2 was mutated with ultraviolent radiation（UV）.we got a mutant UV HB2-1 COD whose removal efficiency was increased obviously up to about 68.2%,which maintained salt-tolerance and genetic stability.更多还原