低温硝基苯降解菌的筛选及降解特性研究

从被硝基苯污染的某河流底泥中分离到能在低温下生长并能以硝基苯为唯一碳源的7株细菌,其中菌株NB1在温度从2.5～35 ℃范围内时都可以生长并矿化20 mg/L的硝基苯,最适宜的生长温度为25 ℃左右;当培养温度为5 ℃时,该菌株在pH为6～9范围内可以快速降解20 mg/L硝基苯,偏碱性的条件比酸性条件更适合其生长;不超过100 mg/L的硝基苯可以被该细菌完全降解.通过生理生化反应特性、菌体形态以及16S rDNA序列测定结果,确定NB1为恶臭假单胞菌(Pseudomonas putida).不同温度条件,特别是低温下该菌株对硝基苯的快速降解特性为低温环境硝基苯污染的生物修复提供了可能.     

Alga-lysing bioreactor and dominant bacteria strain

Alga-lysing bacteria have been paid much attention to in recent years. In this study, the alga-lysing strain P05 which was isolated from an immobilizing biosystem was immobilized by coke and elastic filler, forming two biological reactors. The removal efficiencies of algae, NH4^＋-N and organic matter using the two reactors were studied. The results showed that strain P05 was an ideal algal-lysing bacteria strain because it was easy to be immobilized by coke and elastic filler which are of cheap, low biodegradability and the simple immobilization procedure. After 7 d filming, the biological film could be formed and the reactors were used to treat the eutrophic water. These two reactors were of stability and high effect with low cost and easy operation. The optimal hydraulic retention time （HRT） of each reactor was 4 h. The algae removal rates were 80.38% and 82.1% （in term of Chl-α） of coke reactor and filler reactor, respectively. And that of NH4^＋-N were 52.3% and 52.7%. The removal rates of CODMn were 39.03% and 39.64%. The strain P05 was identified as Bacillus sp. by PCR amplification of the 16S rRNA gene, BLAST analysis, and comparison with sequences in the GenBank nucleotide database.     

T-RFLP方法分析城市污水处理厂中细菌群落的动态变化

采用基于16SrRNA基因的末端限制性片段长度多态性技术(T-RFLP),分析了功能稳定的2个城市污水处理系统中(系统A及系统B),细菌群落结构在105d中的动态变化.在研究中,系统A和系统B功能稳定,BOD出水浓度均在8mg/L左右,总氮(TN)出水浓度分别在25mg/L和23mg/L之下.T-RFLP图谱分析表明,系统A中,115、118、123、471、482和835bp等T-RFs的相对丰度变化显著,系统B中,123、471、750和835bp等T-RFs的相对丰度变化显著.移动窗口分析表明,系统A中细菌群落的平均变化率Δt(15d)为21.5%±5.7%,系统B的平均变化率Δt(15d)为22.6%±5.0%.洛伦兹曲线分析表明,系统A中20%的微生物的累积相对丰度为43%～50%;系统B中20%的微生物的累积相对丰度为47%～52%.结果表明,在城市污水处理厂中,稳定的功能并没有藕联着稳定的细菌群落结构.     

辽河口湿地沉积物硝化细菌及硝化作用研究

2009年6月和8月,采用现场培养和实验室模拟培养相结合的方法对辽河口湿地表层沉积物硝化细菌数量、硝化速率及影响因素进行了研究.结果表明,辽河口湿地表层沉积物氨氧化细菌(ammonia-oxidizing bacteria,AOB)数量6月在0.54×104～5.69×104个.g-1之间,平均值为(2.21±2.32)×104个.g-1,8月在1.90×104～7.90×104个.g-1之间,平均值为(3.61±2.87)×104个.g-1;沉积物潜在硝化速率6月在9.72～16.45 mmol.(m2.h)-1之间,平均值为(12.54±3.14)mmol.(m2.h)-1,8月在14.66～24.62 mmol.(m2.h)-1之间,平均值为(18.71±4.21)mmol.(m2.h)-1;净硝化作用速率6月(S1站)为0.41 mmol.(m2.h)-1,8月在0.20～0.53 mmol.(m2.h)-1之间,平均值为(0.35±0.16)mmol.(m2.h)-1.潜在硝化速率显著高于净硝化速率,AOB数量、净硝化作用速率和潜在硝化作用速率均表现为8月高于6月,芦苇根际效应对硝化作用有促进作用.通过SPSS 13.0软件统计分析,表明影响辽河口湿地表层沉积物硝化作用的主要环境因子有上覆水NH 4+-N浓度和沉积物pH、有机质、总氮(TN)、总磷(TP)、NH 4+-N含量以及AOB数量(p0.05),其中上覆水NH 4+-N浓度和沉积物总磷(TP)、NH 4+-N含量对硝化作用影响较大,是辽河口湿地硝化作用影响的关键因素.根据研究结果估算辽河口湿地沉积物硝化作用每天可以将1.14×105kg的NH 4+-N转化为NO 3--N,对河口湿地氮的循环具有重要意义.     

Comparative study of heavy metal and pathogenic bacterial contamination in sludge and manure in biogas and non-biogas swine farms

The objective of this study is to determine and compare the heavy metal (Zn, Cu, Cd, Pb) and bacterial (E. coli, coliform and Salmonella spp.) contamination between swine farms utilizing biogas and non-biogas systems in the central part of Thailand. Results showed that average levels of E. coli, coliform, BOD, COD, Zn, Cu and Pb in sludge from the post-biogas pond were higher than the standard limits. Moreover, the levels of E. coli, coliform, Cd and Pb were also higher than the standard limits for dry manure. The levels of E. coli, coliform and BOD on biogas farms were lower than on non-biogas farms. Following isolation of Salmonella spp:; it was found that Salmonella serovars Rissen was the most abundant at 18.46% (12/65), followed by Anatum 12.31% (8/65), and Kedougou 9.23% (6/65). The pathogenic strains of Salmonella serovars Paratyphi B var. java and Typhimurium were present in equal amounts at 4.62% (3/65) in samples from all swine farms. This study revealed that significant reduction in E. coli and coliform levels in sludge from covered lagoon biogas systems on swine farms. The presence of Salmonella as well as Cd and Pb, in significant amount in dry manure, suggests that there is a high probability of environmental contamination if it is used for agricultural purposes. Thus, careful waste and manure disposal from swine farms and the regular monitoring of wastewater is strongly recommended to ensure the safety of humans, other animals and the environment.     

产表面活性剂根际菌协同龙葵修复镉污染土壤

从某矿区重金属污染的土壤中分离筛选出一株能产生物表面活性剂的根际细菌LKS06,经生理生化特征及16S rDNA序列分析,将其鉴定为假单孢菌属(Pseudomonas sp.LKS06).生物学特性的测定表明,菌株LKS06对多种重金属有很高的耐受性,且具有分泌吲哚乙酸、产铁载体和ACC脱氨酶活性的能力,并对土壤重金属...     

新型专性厌氧菌利用葡萄糖进行发酵产氢的实验研究

采用批式发酵法对厌氧产氢菌株Bacteria.P利用葡萄糖发酵,在底物浓度、初始pH值、接种比例等不同培养条件下的产氢能力进行了研究。结果表明:专性厌氧菌P是一种高效产氢的菌株,在葡萄糖质量浓度为10 g/L、初始pH为6.0、接种比例为1∶20时,发酵气体总产量和细胞干重达到最大值,分别为485 mL和0.836 g/L。     

东胜区三台基水库水质细菌的鉴定

为了初步探索环境微生物的快速测定法,提升应对微生物污染突发事件的能力,本文运用美国BD公司的细菌鉴定系统对东胜区三台基水库水质细菌进行了鉴定。结果共鉴定出6种细菌,其可信度分别为95.7、99．1、94．3、98．7、98．5、和99．2。结果表明该系统快速、准确、可靠,可以作为环境微生物分类鉴定和微生物污染突发事件应急监测的依据。     

长江口邻近海域沉积物中厌氧氨氧化细菌分布特征研究

海洋生态系统氮素循环对维持海洋生态收支平衡具有重要意义,由厌氧氨氧化细菌(anaerobic ammonia-oxidizing bacteria,ANAMMOX Bacteria)推动的厌氧氨氧化过程是海洋氮素移除的重要途径.本研究采用荧光定量PCR(q PCR)技术,并结合环境理化因子,分析了2011年夏季长江口邻近海域沉积物中厌氧氨氧化细菌的种群丰度分布特征.结果表明,厌氧氨氧化细菌的种群丰度在长江口邻近海域的空间分布与环境因子密切相关,总有机碳含量、盐度、铵盐浓度对长江口邻近海域沉积物中厌氧氨氧化细菌的种群丰度具有重要调控作用.厌氧氨氧化细菌的丰度分布与总有机碳含量呈显著正相关关系(P0.01,r=0.69),同时又随亚硝酸盐浓度、溶解氧浓度的升高而降低,而盐度对厌氧氨氧化细菌丰度分布的影响较为复杂.     

炼厂污水处理泡沫的产生及其处理方法

在炼厂污水处理过程中,生化系统活性污泥曝气池中产生泡沫现象是一种常见问题,主要是由于放线菌和丝状菌菌属的异样生长所造成。通过理论与实践探索,发现污水温度、pH值、溶解氧、污泥停留时间是影响泡沫产生的重要因素。泡沫的产生影响水处理的日常操作、装置运行、出水水质等,其处理方法有物理法、投加化学药剂、生物控制等,其中生物控制法是最优方法。