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。     

Reduction and characterization of bioaerosols in a wastewater treatment station via ventilation

Bioaerosols from wastewater treatment processes are a significant subgroup of atmospheric aerosols. In the present study,airborne microorganisms generated from a wastewater treatment station(WWTS) that uses an oxidation ditch process were diminished by ventilation.Conventional sampling and detection methods combined with cloning/sequencing techniques were applied to determine the groups,concentrations,size distributions,and species diversity of airborne microorganisms before and after ventilation. There were 3021 ± 537 CFU/m3 of airborne bacteria and 926 ± 132 CFU/m3 of airborne fungi present in the WWTS bioaerosol.Results showed that the ventilation reduced airborne microorganisms significantly compared to the air in the WWTS. Over 60% of airborne bacteria and airborne fungi could be reduced after4 hr of air exchange. The highest removal(92.1% for airborne bacteria and 89.1% for fungi) was achieved for 0.65–1.1 μm sized particles. The bioaerosol particles over 4.7 μm were also reduced effectively. Large particles tended to be lost by gravitational settling and small particles were generally carried away,which led to the relatively easy reduction of bioaerosol particles0.65–1.1 μm and over 4.7 μm in size. An obvious variation occurred in the structure of the bacterial communities when ventilation was applied to control the airborne microorganisms in enclosed spaces.     

Characterization of extracellular polymeric substances in the biofilms of typical bacteria by the sulfur K-edge XANES spectroscopy

A combined approach of physicochemical extraction and sulfur K-edge X-ray absorption near-edge structure（XANES） spectroscopy was applied to characterize the extracellular polymeric substances（EPS） of typical bacterial biofilms in this study. Physicochemical analysis showed variation of the contents of DNA,polysaccharide and protein in different fractions of EPS in different mediums. The sulfur K-edge XANES analysis yielded a variety of spectra.Spectral fitting of the XANES spectra utilizing a large set of model compounds showed that there was more reduced sulfur in both LB-EPS（loosely bound EPS） and TB-EPS（tightly bound EPS） of all the biofilms in LB medium than in R2 A medium. More oxidized sulfur was identified in LB-EPS than that in TB-EPS,suggesting different niches and physiological heterogeneity in the biofilms. Our results suggested that the sulfur K-edge XANES can be a useful tool to analyze the sulfur speciation in EPS of biofilms.     

南京市黑臭河流水体中细菌多样性的研究

以南京市城南河为研究对象,分别提取上中下游的水体样本,分析水质中的氮、磷、COD等水质指标,并利用变性梯度凝胶电泳技术(DGGE)分析了城南河不同位置的细菌多样性。结果表明:城南河水体中的平均总氮为30.06 mg/L,总磷为6.14 mg/L,COD为42.03 mg/L,均超过国家V类水质标准。结合外观,城南河属于严重污染的典型黑臭河流。DGGE分析的结果表明:城南河具有较高的细菌多样性,优势菌群主要是变形菌门和拟杆菌门2大类群,且不同取样点细菌种类差别不大。     

石油污染对海水中细菌数量和酶活性的影响

在实验室条件下,研究了不同浓度(0,0.05 mg/L,0.15 mg/L,0.45 mg/L和1.35 mg/L)的石油,对海水中细菌数量和酶活性在短期(96 h)和较长期(28 d)内的影响,结果表明:(1)海水中的细菌数量随着石油污染时间和浓度的不同,表现出不同的变化特征。可培养异养菌数在96 h内,所有实验组均呈现先升高后下降的趋势,其后低浓度实验组保持缓慢上升至7 d后数值维持稳定,但最高浓度组(1.35 mg/L)海水中的异养细菌数在7 d后明显下降,之后逐渐上升。实验持续28 d时,各组间差别不显著(P0.05)。在培养24 h时,各实验组细菌总数有明显增长,且随石油浓度增加而升高,随后其变化没有明显规律,但培养7 d后,较低浓度组细菌总数一直高于对照组,而高浓度组(1.35 mg/L)细菌总数一直低于对照组。(2)石油污染对海水中细菌脱氢酶和超氧化物歧化酶(SOD)具有诱导作用。细菌脱氢酶活性和SOD活性分别在培养72 h和24 h时显著升高,且随着石油浓度增加,其活性上升。经过长时间培养后,细菌酶活恢复正常,与对照组没有显著差别。     

重金属抗性解磷细菌的磷溶解特性研究

从湖南省湘西州花垣县的铅锌矿表层土壤中,筛选出两株具有重金属抗性和解磷特性的细菌T PSB1和T PSB2.通过16S rRNA基因序列比对,分别鉴定为嗜麦芽寡养单胞菌(Stenotrophomonas maltophilia)和唐菖蒲伯克霍尔德菌(Burkholderia gladioli).T PSB1和T PSB2在含有难溶性无机磷液体培养基中,其上清液的可溶性磷含量最高分别达到了402.9 mg·L-1和589.9 mg·L-1;在难溶性有机磷固体和液体培养基中,固体平板上均出现解磷圈,而液体培养基上清液中,可溶性磷含量也分别达到了2.97 mg·L-1和4.69 mg·L-1.另外,两株细菌对重金属Zn2+的抗性最高,在其浓度为2000 mg·L-1固体和液体培养基条件下均可以生长,磷溶解浓度分别为114.8 mg·L-1和125.1 mg·L-1.而在含铬和铅的浓度为1 000 mg·L-1的液体培养基中,两株细菌同样表现出重金属抗性.在Pb2+浓度为1000 mg·L-1的液体培养基中,磷溶解浓度分别达到了57.9 mg·L-1和71.7 mg·L-1;而在Cr2+浓度为1000 mg·L-1的培养基中磷溶解浓度分别为60.1 mg·L-1和98.4 mg·L-1.