含氟有机化合物优势降解菌的筛选

从受含氟有机物长期污染的污泥中驯化筛选得到7株优势降解菌,可利用氟代有机化合物为唯一碳源生长。取其中2株菌进行生物忍耐力及生物降解实验,结果表明:菌株对含氟有机物有较强的忍受能力,在浓度高达1000mg/L的条件下仍能生长;生物降解实验中全氟辛酸可被筛选菌脱氟降解。     

生物法净化气态污染的系统研究

废气生物净化技术具有传统净化方法不可比拟的优越性和安全性 ,从微生物的驯化培养、环境及营养条件的优化、填料介质的选择、理论模式的发展和净化设备的开发等方面讨论了生物法在大气污染控制中的应用研究情况     

Di(2-ethylhexyl)phthalate and mono(2-ethylhexyl)phthalate in media for in vitro fertilization

In vitro fertilization (IVF) is one of the most important treatments of infertility to provide a chance of conceiving. In IVF treatment, sperm are washed and motile sperm are isolated with sperm washing media (SWM) for the purpose of fertilization; fertilized ova are then incubated for a maximum of 5 or 6 d in media for IVF (IVFM). The exposure of fertilized ova to chemicals via such media has not been studied. We determined the concentrations of two contaminants; di(2-ethylhexyl)phthalate (DEHP) and its hydrolyzed product mono(2-ethylhexyl)phthalate (MEHP) in IVFM, SWM, and protein sources (PS: human serum albumin or serum substitute) for IVFM and SWM. The DEHP and MEHP in these media were extracted by a liquid-liquid extraction method and their concentrations determined by liquid chromatography coupled with tandem mass spectrometry (LC-MS/MS). Fifteen IVFM, nine SWM, and six PS obtained in Japan were examined. The concentrations of DEHP and MEHP in IVFM and SWM were <10-114 and <2.0-263 ng mL⁻¹, respectively. The concentrations of both DEHP and MEHP were higher in the media containing PS than in those without PS. Either MEHP alone or both DEHP and MEHP were detected in PS. The concentrations of DEHP and MEHP in PS were <10-982 and 47.0-1840 ng mL⁻¹, respectively. The DEHP and MEHP detected in these media were derived from PS. This is the first study on the chemical contamination of IVFM, SWM, and PS.     

土壤中好氧反硝化菌的分离及脱氮特性研究

采用极限稀释、滴加格里斯试剂和二苯胺试剂鉴别、平板划线相结合的方法,从土壤中分离到1株能以硝酸钾为氮源进行好氧反硝化作用的细菌,命名为LD3,菌株革兰氏染色为阳性,形状为杆状和球状,菌落光滑湿润,呈白色,菌株LD3鉴定为脂肪杆菌属。对菌株LD3反硝化能力进行了研究,结果表明,LD3菌株在好氧条件下能有效去除培养液中的硝...     

低温喹啉降解菌的筛选及降解性能

从吉林石化污水处理厂的活性污泥中驯化、筛选获得一株降解效率高且生长速率快高效耐冷菌,命名为WS-5.该菌能以喹啉作为惟一的碳源、氮源及能源.结合菌体的形态观察、生理生化特性实验及16S rDNA序列同源性对比分析,鉴定菌株WS-5为恶臭假单胞菌(Pseudomonas putida).不同降解条件下的实验结果表明,菌株WS-5的最佳降解条件是投菌量为15％,pH值范围在8～10,摇床转速为100 r/min.最佳降解环境下对200 mg/L的喹啉在132 h降解率达到了85.3％.菌株WS-5对初始喹啉浓度为50、100、200和300 mg/L的初始喹啉浓度分别在36、72、192和262 h内完全降解.这将为今后在低温条件下处理含喹啉废水提供技术指导.     

Simple analytical method for determination of pesticide residues in human serum by liquid chromatography tandem mass spectrometry

The aim of this study was to develop an analytical method for the determination of residues of organophosphorus and carbamate pesticides which are widely used in Tunisia. This method involves a liquid-liquid extraction procedure followed by liquid chromatography tandem mass spectrometry (LC/MS/MS) for the identification and quantification of compounds. Ionization of molecules was performed by the electrospray mode. Multiple reactions monitoring (MRM) was the acquisition mode used for the monitoring of two MS/MS transitions for each compound. The average recoveries obtained, at three different fortification levels, ranged between 65% and 106% for most of the pesticides studied, except for methamidophos (lower than 25%).The linearity of the method was in the range of 5 to 50 μ g/L with a correlation coefficient from 0.995 to 0.999, depending on the analyte. The estimated limit of detection and limit of quantification were 2 μ g/L and 5 μ g/L, respectively. The precision of the analytical procedure was satisfactory and the coefficients of variation, evaluated at three concentration levels were lower than 15% for most pesticides studied. The application of the method was investigated in a population of agricultural workers chronically exposed to various pesticides some of which, such as carbofuran, carbendazim, methomyl and pirimicarb, were detected in some serum samples.     

纳污水体中好氧脱氮菌的筛选与氨氮去除特性

采用异养硝化培养基从城市纳污水体中富集好氧脱氮菌,将得到的富集菌种分离纯化,得到1株好氧脱氮菌NC1,对氨氮的去除率为72.6%;好氧菌株NC1繁殖较快,生长3~4 h即进入对数生长期,有一定实用意义。考察了在不同条件下菌NC1对氨氮的去除效果,发现当pH为6~9之间、转速超过100 r/min、温度为30℃、碳氮比为6~12时对氨氮的去除效果较好。NC1在去除氨氮过程中pH值升高,且能在异养条件下利用亚硝酸盐和硝酸盐生长。     

一株高效降酚菌的分离鉴定及降酚特性研究

以苯酚为唯一碳源,采用逐量分批的方法从被酚类物质污染的土壤中驯化、筛选、分离降酚菌,利用形态学、培养特性、生理生化反应以及分子手段鉴定所得菌株,研究了该菌株生长与降酚的关系以及其降酚能力,并设计引物检测降酚酶基因。结果表明,获得的一株高效降酚菌GDYW-0027经鉴定为不动杆菌属(Acinetobacter),它的生长速率与苯酚的降解速率基本同步,48h内对高质量浓度(2.2g/L)苯酚的降解率为86.73%;在菌株GDYW-0027中检测到苯酚羟化酶及邻苯二酚2,3双加氧酶基因片段,推测其采用间位开环方式打开苯环。     

一株生物表面活性剂产生菌的筛选鉴定及其特性

利用蓝色凝胶平板筛选法,从华北某油田受污染的土壤中分离筛选得到1株优良的生物表面活性剂产生菌H1.通过生理生化特征及16S rRNA基因序列相似性分析,将其鉴定为肺炎克雷伯氏菌(Klebsiella pneumoniae).薄层层析和红外光谱分析表明,该菌株所产生物表面活性剂为磷脂类生物表面活性剂.对其所产生物表面活性剂的稳定性进行研究,并考察影响该生物表面活性剂合成的因素.稳定性实验显示,该生物表面活性剂可耐受90℃的高温,对pH有较广泛的适应性(pH6.5～11.0),NaCl浓度对其生物活性影响不大.以蔗糖为碳源,硝酸铵为氮源,初始pH 6.5 ～7.0,30℃的培养条件有利于该生物表面活性剂的合成,生物表面活性剂的产量可达0.742 g/L.该研究成果可为原油的驱油降黏提供有效的菌源和理论依据.