游离附生假单胞菌对铜绿微囊蓝细菌中32P释放的影响

采用同位素示踪法，分析游离附生假单胞菌(Pseudomonas sp-)对富集^32P的铜绿微囊蓝细菌(Microcystis aeruginosa)中磷释放的影响．研究结果表明：在微囊蓝细菌生长的延迟期和对数期．游离附生假单胞菌的加入抑制了微囊蓝细菌中^32P的释放，而对蓝细菌的生长没有明显的影响；在微囊蓝细菌生长的稳定期和衰减期，假单胞菌促进其蓝细菌细胞内^32P的释放，同时也加速微囊蓝细菌的衰亡．假单胞菌对微囊蓝细菌^32P释放的促进作用是由于自身的吸磷能力导致的．假单胞菌的吸磷量由假单胞菌生物量和细胞内磷浓度决定，假单胞菌在微囊蓝细菌的整个生长阶段生物量不断增加，而体内^32P浓度在开始阶段很低．直到微囊蓝细菌进入稳定期才达到相对稳定。     

萘降解菌N19-3的分离、鉴定和萘双加氧酶基因的检测

从石油污染土壤中分离到一株高效降解萘的N19-3菌株. 经形态观察、生理生化实验和16S rDNA序列分析等鉴定其为丛毛单胞菌属（Comamonas sp.）. 该菌株能在30 ℃,30h内将1 000mg/L的萘完全降解. 降解萘的适宜温度为20～30 ℃, 适宜pH为7.0～9.0. 0.1mmol/L的Ca2+和Fe3+对N19-3菌株降解萘有较强的促进作用, 0.1 mmol/L的Mn2+和Zn2+对N19-3菌株的生长和萘的降解也有一定的促进作用, 而0.1 mmol/L的 Cu2+则完全抑制了N19-3菌株的生长和萘的降解. 通过PCR方法在N19-3菌株中扩增出分别与C. testosteroni H菌株的萘双加氧酶铁硫蛋白大亚基基因（pahAc）与双加氧酶铁硫蛋白小亚基基因（pahAd）高度同源的核苷酸片断.      

3株溶藻细菌的分离鉴定及其溶藻效应

从武汉市的池塘分离到3株编号分别为M6,M8和M13的溶藻细菌,对这3株细菌的生理生化特性、溶藻专一性和溶藻原因进行了研究.结果表明:M6,M8和M13分别属于葡萄球菌属(Staphylococcus sp.)、芽孢杆菌属(Bacillus sp.)和节杆菌属(Arthrobacter sp.);它们分别能溶解鲍氏织线藻、念珠藻、鱼腥藻、坑形席藻、铜绿微囊藻、鞘丝藻等多种蓝藻,并且它们的液体溶藻现象较固体溶藻现象明显;3株溶藻细菌培养液的过滤液仍有溶藻效应,说明溶藻原因可能是细菌释放某种化学物质所致.      

苯并噻吩脱硫菌株的筛选及脱硫活性研究

从孤岛油田油浸土样中筛选到1株能降解苯并噻吩(BT)的脱硫菌,经初步鉴定该菌为戈登氏菌属(Gordona sp.).实验证明:该菌能以类似于4S途径脱除BT及其衍生物中的硫,但是不能脱除二苯并噻吩(DBT)及其衍生物中的硫.GC-MS分析表明该途径的终产物为邻羟基苯乙醛或其异构体苯并呋喃.在以BT为唯一硫源的培养基中30℃培养48h,Gordona sp.C-6能降解0.15mmol/L的BT,终产物占发酵培养基中BT加入量的50%,其余BT在有氧培养过程中挥发.通过Matlab拟合曲线确定以邻羟基苯乙酸为标准品进行产物定量检测的方法.     

Microbial reduction of uranium (VI) by Bacillus sp. dwc-2: A macroscopic and spectroscopic study

The microbial reduction of U(VI) by Bacillus sp. dwc-2, isolated from soil in Southwest China, was explored using transmission electron microscopy (TEM), X-ray photoelectron spectroscopy (XPS) and X-ray absorption near edge spectroscopy (XANES). Our studies indicated that approximately 16.0% of U(VI) at an initial concentration of 100 mg/L uranium nitrate could be reduced by Bacillus sp. dwc-2 at pH 8.2 under anaerobic conditions at room temperature. Additionally, natural organic matter (NOM) played an important role in enhancing the bioreduction of U(VI) by Bacillus sp. dwc-2. XPS results demonstrated that the uranium presented mixed valence states (U(VI) and U(IV)) after bioreduction, which was subsequently confirmed by XANES. Furthermore, the TEM and high resolution transmission electron microscopy (HRTEM) analysis suggested that the reduced uranium was bioaccumulated mainly within the cell and as a crystalline structure on the cell wall. These observations implied that the reduction of uranium may have a significant effect on its fate in the soil environment in which these bacterial strains occur.     

Decolorization of molasses melanoidins and palm oil mill e uent phenolic compounds by fermentative lactic acid bacteria

Lactobacillus plantarum SF5.6 is one of the lactic acid bacteria (LAB) that has the highest ability of molasses melanoidin (MM) decolorization among the 2114 strains of LAB. The strains were isolated from spoilage, pickle fruit and vegetable, soil and sludge from the wastewater treatment system by using technical step of enrichment, primary screening and secondary screening. This LAB strain SF5.6 was identified by 16S rDNA analysis and carbohydrate fermentation (API 50 CH). The top five LAB strains having high MM decolorization (> 55%), namely TBSF5.8-1, TBSF2.1-1, TBSF2.1, FF4A and SF5.6 were selected to determine the optimal condition. It was found that the temperature at 30°C under facultative conditions in GPY-MM medium (0.5% glucose, 0.1% peptone, 0.1% yeast extract, 0.1% sodium acetate, 0.05% MgSO4 and 0.005% MnCl2 in MM solution at pH 6) giving a high microbial growth and MM decolorization for all five strains. It was noticed that the decolorization of MM by LAB strains might be cell growth associated. L. plantarum SF5.6 grew rapidly within one day while the other strains took 2–3 days. This L. plantarum SF5.6 could rapidly decolorize MM to 60.91% without any lag phase, and it also had the ability to remove 34.00% phenolic compounds and 15.88% color from treated palm oil mill e uent.     

Biodegradation of phenol by free and immobilized Acinetobacter sp. strain PD12

A new phenol-degrading bacterium with high biodegradation activity and high tolerance of phenol, strain PD 12, was isolated from the activated sludge of Tianjin Jizhuangzi Wastewater Treatment Facility in China. This strain was capable of removing 500 mg phenol/L in liquid minimal medium by 99.6% within 9 h and metabolizing phenol at concentrations up to 1100 mg/L. DNA sequencing and homologous analysis of 16S rRNA gene identified PD12 to be an Acinetobacter sp. Polyvinyl alcohol （PVA） was used as a gel matrix to immobilize Acinetobacter sp. strain PDI2 by repeated freezing and thawing. The factors affecting phenol degradation of immobilized cells were investigated, and the results showed that the immobilized cells could tolerate a high phenol level and protected the bacteria against changes in temperature and pH. Storage stability and reusability tests revealed that the phenol degradation functions of immobilized cells were stable after reuse for 50 times or storing at 4℃ for 50 d. These results indicate that immobilized Acinetobacter sp. strain PD 12 possesses a good application potential in the treatment of phenol-containing wastewater.     

微生物-化学水解联合作用下烟嘧磺隆的降解

从被烟嘧磺隆污染的人工湿地土壤中分离出1株能够在葡萄糖存在下降解烟嘧磺隆的微生物,通过16S rDNA序列同源相似性分析,初步鉴定该微生物为Klebsiella sp..它能够以烟嘧磺隆为唯一氮源生长,其最适生长条件为:温度35℃,初始pH为中性偏酸.水解试验表明,烟嘧磺隆在中性和碱性条件下比较稳定,在酸性条件下水解较快.生物降解试验发现,当培养液中葡萄糖浓度为5 g.L-1时,在温度35℃、初始pH为7的条件下培养10 d后烟嘧磺隆有99.4%得到降解,同时溶液的pH从7.0降低至4.0;而降低葡萄糖浓度分别为500 mg.L-1和100 mg.L-1时,培养10 d后烟嘧磺隆的降解率仅为11.7%和6.6%,溶液的pH始终在7左右.进一步研究表明烟嘧磺隆的降解是由于微生物代谢葡萄糖产生了酸性环境,pH降低引起了烟嘧磺隆水解,菌种对烟嘧磺隆降解的实质是微生物-化学水解联合作用.     

链霉菌(Streptomyces sp.)对吡啶的降解特性

从焦化废水的活性污泥中分离出对溶液中吡啶具有降解效果的链霉菌（Streptomyces sp．）,考察了吡啶初始质量浓度、初始pH、降解温度、振荡速度等对吡啶降解效果的影响,初步探讨了该菌降解吡啶的动力学与机理。实验结果表明,该菌对吡啶有很强的耐受力,能以吡啶为惟一碳源和氮源生长。链霉菌在初始pH=8、降解温度30℃、振荡速度100r／min的条件下培养7d后,吡啶的质量浓度从250mg/L降至6．6mg/L,吡啶降解率达97．4％。该菌对吡啶的降解反应符合一级动力学方程,初始质量浓度为100mg／L时的吡啶降解速率常数为0．4011d^-1。紫外一可见光谱分析表明,吡啶经该菌降解后的特征环被破坏。     

1株海洋异养硝化-好氧反硝化菌的分离鉴定及其脱氮特性

以海水为基质,采用传统的微生物分离纯化方法,从海底沉积物中分离筛选得到1株耐盐异养硝化-好氧反硝化细菌y5,经形态、生理生化特性以及16S rRNA基因序列分析,鉴定该菌为克雷伯氏菌(Klebsiella sp.).对其脱氮特性及影响因素进行了研究,结果表明,菌株y5的最佳碳源为柠檬酸三钠,最适p H值为7.0,最适C/N为17.菌株均能以NH4Cl、Na NO2和KNO3为唯一氮源进行反应,36 h的去除率分别为77.07%、64.14%和100%.3种氮源共存时,36 h的去除率达到100%.表明菌株y5在高盐废水中具有独立高效的异养硝化和好氧反硝化作用.