油田硫酸盐还原菌快速定量检测方法

现有油田废水中硫酸盐还原菌检测周期长、检测费用较高,本研究应用聚合酶链式反应(PCR)技术与倍比稀释法(MPN)相结合的DSR-MPN-PCR法,对硫酸盐还原菌进行快速定量检测.从废水中制备了直接用于PCR扩增的菌液,保证了定量准确性;建立以硫酸盐还原菌亚硫酸盐还原酶基因(Dsr)为靶位点的通用探针DSR1F和DSR5R的反应体系和扩增条件.结果表明,该方法检测灵敏度明显比液体稀释培养法高2个数量级,真实地表征了废水中实际的SRB菌数量,整个操作过程需要3～4　h,检测结果非常稳定,降低了检测费用,可以在生产中应用.     

Analysis of bacterial community structures in two sewage treatment plants with different sludge properties and treatment performance by nested PCR-DGGE method

The bacterial community structures in two sewage treatment plants with different processes and performance were investigated by denaturing gradient gel electrophoresis （DGGE） of nested polymerase chain reaction （nested PCR） amplified 16S rRNA gene fragments with group-specific primers. Samples of raw sewage and treated effluents were amplified using the whole-cell PCR method, and the activated sludge samples were amplified using the extracted genomic DNA before the PCR products were loaded on the same DGGE gel for bacterial community analysis. Ammonia-oxidizing bacterial and actinomycetic community analysis were also carried out to investigate the relationship between specific population structures and system or sludge performance. The two plants demonstrated a similarity in bacterial community structures of raw sewage and activated sludge, but they had different effluent populations. Many dominant bacterial populations of raw sewage did not appear in the activated sludge samples, suggesting that the dominant bacterial populations in raw sewage might not play an important role during wastewater treatment. Although the two plants had different sludge properties in terms of settleability and foam forming ability, they demonstrated similar actinomycetic community structures. For activated sludge with bad settling performance, the treated water presented a similar DGGE pattern with that of activated sludge, indicating the nonselective washout of bacteria from the system. The plant with better ammonium removal efficiency showed higher ammonia-oxidizing bacteria species richness. Analysis of sequencing results showed that the major populations in raw sewage were uncultured bacterium, while in activated sludge the predominant populations were beta proteobacteria.     

Characterization of a salt-tolerant bacterium Bacillus sp. from a membrane bioreactor for saline wastewater treatment

High salt concentrations can cause plasmolysis and loss of activity of cells, but the salt-torlerant bacterium can endure the high salt concentrations in wastewater. In this research 7 salt-torlerant bacteria, which could survive in dry powder products and could degrade organic contaminants in saline wastewater, were isolated from a membrane bioreactor. The strain NY6 which showed the fastest growth rate, best property for organic matter degradation and could survive in dry powder more than 3 months was selected and characterized. It was classified as Bacillus aerius based on the analysis of the morphological and physiological properties as well as the 16 S rRNA sequence and Neigh borjoining tree. The strain NY6 could survive in the salinity up to 6% and the optimal growth salinity is2%; it belongs to a slightly halophilic bacterium. The capability of its dry powder products for COD removal was 800 mg COD/(g·day) in synthesized saline wastewater with salinity of 2%. According to salt-tolerant mechanism research, when the salinity was below 2%, the stain NY6 absorbed K+and Na+to maintain osmotic equilibrium, and when the salinity was above 2%, the NY6 kept its life by producing a large amount of spores.     

芽孢杆菌SeRB-2还原亚硒酸盐的动力学研究

微生物还原亚硒酸盐的动力学研究具有重要的现实意义,可以为Se (IV)污染场地的微生物修复设计提供理论依据。本文研究了兼性厌氧菌Bacillus sp.SeRB-2对亚硒酸钠的还原动力学。通过指数方程模型、对数方程模型和米氏方程模型的分析可知,Se (IV)的细菌还原符合一级反应动力学,还原反应主要集中在对数期和稳定生长前期,米氏方程模型能更好的反映细菌对亚硒酸盐的还原过程。通过对不同Se (IV)浓度下的米氏常数(K_m)和最大反应速率(V_max)的分析发现,当Se (IV)浓度较低时,K_m值较小,V_max值较大,这表明Se (IV)浓度越低,还原亚硒酸盐的酶与Se (IV)的结合能力越强,此时细菌对亚硒酸盐的还原速率越大、还原效率也越高。在本研究中,当Se (IV)浓度为1 mmol/L时,其还原效率最高可达90%,能够有效去除或降低Se (IV)污染,说明该菌在Se (IV)污染场地的生物修复上具有应用潜力。     

含硫酸盐有机废水的厌氧生物处理

本文对硫酸盐在废水的厌氧生物处理过程中的影响进行了综述.着重论述了厌氧消化中硫酸盐还原菌和产甲烷茵竞争基质的机理,硫化物对甲烷菌的抑制作用,并介绍含硫酸盐废水的处理工艺,及厌氧出水中硫化物去除的方法.     

兰州市空气微生物分析

对兰州市30个点的空气微生物进行了监测研究报道。结果表明：兰州市空气微生物属于中度污染，主要优势菌种有蜡样芽胞杆菌，枯草芽胞杆菌，金黄色葡萄球菌和8叠球菌。白曲霉，青霉属，黄曲霉，木霉，交链孢霉，空气微生物含量与地面人类活动关系密切，与人流量（人口密度）和车流量显著相关；绿地对空气微生物年代有显著的杀灭作用。尤其是乔灌草相结合的复合型绿地杀菌作用很理想。     

具菲降解特性植物内生细菌的分离筛选及其生物学特性

从长期受石油污染的植物体内分离到内生细菌36株,通过平皿促生和定殖试验筛选出1株能高效降解菲并明显促进小麦生长、能在小麦体内良好定殖的内生细菌7J2菌株.同时,对菌株7J2的生物学特性进行了研究.结果表明,菌株7J2在菲含量为30 mg·L-1的条件下,28℃振荡培养6d,菲的降解率达到99.81%.菌株7J2能够产生吲哚乙酸(IAA)(3.4±0.2)mg·L-1)和铁载体(2,3-二羟基苯甲酸)(4.3±1.6) mg·L-1).振荡培养3d,接活菌的培养基中有效磷浓度比接灭活菌的处理增加了32.5%.另外,菌株7J2对重金属Pb2 、Cr2 、Cu2 、Ni2 、Zn2 、Cd2 均有较强的抗性.通过16SrDNA序列测定,菌株7J2属于肠杆菌属.     

Isolation,identification and desulfurization mechanism of a sulfur-oxidizing bacterium with salt tolerance北大核心CSCD

Micro-organism with efficient desulfurization performance is a key factor in the biological desulfurization technology. This study aimed to seek such a sulfur-oxidizing strain and understand its desulfurization mechanism. Wastewater in a sewage station of natural gas purification plant was used to screen the sulfide-oxidizing strain, and to identify it based on sequence similarity analysis of 16S rDNA and the morphological characteristics. Thiosulfate was used as substrate for investigating the sulfur oxidation performance and salinity tolerance; the OD600, content change of thiosulfate, sulfate, sulfur, pH and total alkalinity in the cultural system were also investigated. The strain DS-B was found to share the highest sequence similarity with Thioalkalivibrio thiocyanoxidans ARh2, therefore determined as Thioalkalivibrio. At the optimum temperature of 35 °C for growth and degradation, the removal efficiency of thiosulfate could reach 98.7% after 7 days. Strain DS-B had strong resistance to thiosulfate, and the optimal concentration of S2O32- was 2 × 104 mg/L. The analysis for sulfur oxides showed that it could oxidize thiosulfate by the pathway of S2O32-→SO42- / S2O32- → S → SO42-. Therefore the strain DS-B is a sulfur-oxidizing bacterium with great application prospect for its strong salt tolerance and conspicuous removal capability for thiosulfate.     

碱性介质中还原高浓度Cr(VI)细菌的分离及其特性

目前国内外处理含铬废水的微生物仅局限于酸性或中性环境,且处理Cr(VI)的浓度仅为200mgL-1左右,难以工业化应用,尤其是不可能处理诸如铬渣渗滤液之类的碱性含铬废水及铬渣.本研究从铬渣堆埋场附近取得菌样,经富集、分离、驯化,得到能在碱性介质中高效还原Cr(VI)的无色杆菌属(Achromobactersp.)菌株,该菌为G-,具有周身鞭毛及可运动性.对其生理及还原Cr(VI)的特性进行了研究,结果表明:该菌嗜碱,好氧,耐盐及高Cr(VI),在有氧、pH为10.30、30℃等条件下,含Cr(VI)1570mgL-1的废水经该菌处理16h后浓度降至0.6mgL-1.处理后的沉淀物中铬以Cr(OH)3的非晶形态存在,其中总铬含量为21.44%,Cr(VI)检测不出,具有很大的回收价值.图4表3参16     

优势工程菌在H/O工艺中处理制药废水的研究

采用水解 (H)—好氧 (O)生化工艺研究了优势复合工程菌对抗生素工业废水有机质的降解能力并进行了处理条件试验研究。探讨了预处理、生化温度、pH值、水力停留时间、进水有机物浓度等因素对生化处理工艺的影响。试验结果表明 ,在选定的条件下 ,水解单元COD的降解率达 71 9%。好氧单元COD的降解率达 62 9% ,总去除率达 98 5%。达到国家规定的制药行业排放标准 ,出水的COD平均浓度低于 30 0mg/L。