红树林土壤解磷菌的分离鉴定及解磷特性

从罗源湾红树林根际土壤中分离解磷菌,筛选出洋葱伯克霍尔德菌（Burkholderia cepacia, NR 113645.1）和短小芽孢杆菌（Bacillus pumilus, NR 043242.1）,研究它们的解磷特性和动态解磷过程. HPLC结果表明, B. cepacia菌液上清中含葡萄糖酸、丙酮酸、乳酸、乙酸、丁二酸, 这些有机酸的产生导致磷酸盐溶解. B.pumilus菌液上清中仅检测到少量的葡萄糖酸, 因此该菌溶磷效果不佳. 在细菌动态溶磷过程中发现, 经B. cepacia菌处理的磷酸钙, 其X射线衍射（XRD）特征峰强度随时间的增长降低, 显微镜图像显示磷酸钙颗粒随时间增长变小, 甚至消失. 而经B.pumilus菌处理的结果表明, 在试验期间内磷酸钙峰强度和颗粒大小没有明显变化. 细菌产生有机酸是溶解磷酸盐的重要前提, 这是解决板结土壤中难溶性磷源转化为生物可利用磷源问题的关键.     

微生物絮凝剂对膨润土悬液的絮凝效果试验

从活性污泥中筛选到20株絮凝剂产生菌，经复筛得到一株高效絮凝剂产生菌MBFⅡ－3，以膨润土悬液为絮凝对象，研究了MBFⅡ－3投加量、温度和pH对絮凝活性的影响；用MBFⅡ－3培养液对生活污水、汾河水等进行了絮凝实验，结果表明，浊度去除率均在90％以上。     

嗜热溶胞菌SY-14的基本特性研究

对从污泥堆肥中分离得到的具有溶胞能力的嗜热产芽孢杆菌SY-14进行了初步鉴定,并对其生长、产酶及溶胞特性进行了研究.根据菌株形态及16S rDNA测序结果,SY-14为土芽胞杆菌属(Geobacillus sp.).SY-14最适生长温度60℃左右,最适生长pH为6.0～7.0.SY-14培养上清液对完整和加热灭活后的微生物细胞都具有溶胞能力,6 h的细胞溶解率分别可达到70%和85%,上清液经过热处理后溶胞能力明显下降,表明溶胞能力主要来自于酶的作用.间歇培养过程中,SY-14培养上清液溶胞活性在对数生长期快速升高,进入稳定期前后达到最大,之后快速下降.SY-14培养上清液对受试的5株革兰氏阴性菌及部分革兰氏阳性菌都具有溶胞能力.     

弧菌拮抗菌的筛选及其对凡纳滨对虾的抑菌防病作用

从海洋沉积物中分离到2株弧菌拮抗菌(H2和H4),经生理生化特性、16S rRNA基因序列分析分别鉴定为短小芽孢杆菌(Bacillus pumilus H2)和地衣芽孢杆菌(Bacillus licheniformis H4). H2和H4菌株均对需钠弧菌的生长有显著的抑制作用;但只有H2菌株在模拟养殖动物小肠环境中生长良好. 选择H2进行模拟试验(20尾凡纳滨对虾虾苗为1组).结果表明,对照组(不接种)虾苗存活32h,接种弧菌的试验组虾苗仅存活16h,同时接种H2菌株和弧菌的试验组虾苗存活48h,而仅接种H2菌株的试验组虾苗存活了72h,说明菌株H2可显著提高凡纳滨对虾的存活时间.现场试验中,100L养殖池中(50尾虾/池),分别接种0 (对照), 103, 104 CFU/mL的H2菌株并养殖14d,再用104 CFU/mL需钠弧菌处理14d.接种104 CFU/mL H2菌株的试验组,虾的死亡率仅为12.5%,显著低于对照组的30.8%(P0.05).     

纳米材料对环境中微生物活性的影响研究

研究纳米材料对环境中微生物细胞活性的影响可为纳米材料的生物安全性评价提供一定的理论基础.以大肠杆菌和枯草芽孢杆菌为受试生物,采用电导率仪测定细菌培养液电导率变化,分别研究了纳米TiO2、纳米ZnO、纳米Fe3O4、纳米SiO2、纳米二氧化钛载银、纳米磷酸锆载银、纳米棕色银对细菌细胞膜通透性的影响.结果表明,纳米材料对革兰氏阳性枯草芽孢杆菌细胞活性影响更大;同种纳米材料,粒径越小,对细菌的细胞活性影响越强;对细菌细胞活性影响最大的是纳米棕色银,对细菌细胞活性影响最小的是纳米SiO2和Fe3O4.     

Effcient degradation of lube oil by a mixed bacterial consortium

A laboratory study was performed to assess the biodegradation of lube oil in bio-reactor with 304# stainless steel as a biofilm carrier. Among 164 oil degrading bacterial cultures isolated from oil contaminated soil samples, Commaonas acidovorans Px1, Bacillus sp. Px2, Pseudomonas sp. Px3 were selected to prepare a mixed consortium for the study based on the e ciency of lube oil utilization. The percentage of oil degraded by the mixed bacterial consortium decreased slightly from 99% to 97.2% as the concentration of lube oil was increased from 2000 to 10,000 mg/L. The degradation of TDOC (total dissolved organic carbon) showed a similar tendency compared with lube oil removal, which indicated that the intermediates in degradation process hardly accumulated. Selected mixed bacterial consortium showed their edge compared to activated sludge. Scanning electron microscopy (SEM) photos showed that biofilms on stainless steel were robust and with a dimensional framework constructed by EPS (extracellular polymeric substances), which could promote the biodegradation of hydrocarbons. The increase of biofilm followed first-order kinetics with rate of 0.216 g glucose/(cm2 day) in logarithm phase. With analysis of Fourier transform infrared spectroscopy (FT-IR) and gas chromatography-mass spectrometry (GC-MS) combined with removal of lube oil and TDOC, mixed bacterial consortium could degrade benzene and its derivatives, aromatic ring organic matters with a percentage over 97%.     

Efficient degradation of lube off by a mixed bacterial consortium

A laboratory study was performed to assess the biodegradation of lube oil in bio-reactor with 304# stainless steel as a biofilm carrier.Among 164 oil degrading bacterial cultures isolated from oil contaminated soil samples, Commaonas acidovorans Pxl, Bacillus sp.Px2, Pseudomonas sp. Px3 were selected to prepare a mixed consortium for the study based on the efficiency of lube oil utilization.The percentage of oil degraded by the mixed bacterial consortium decreased slightly from 99% to 97.2% as the concentration of lube oil was increased from 2000 to 10,000 mg/L. The degradation of TDOC (total dissolved organic carbon) showed a similar tendency compared with lube oil removal, which indicated that the intermediates in degradation process hardly accumulated. Selected mixed bacterial consortium showed their edge compared to activated sludge. Scanning electron microscopy (SEM) photos showed that biofilms on stainless steel were robust and with a dimensional framework constructed by EPS (extracellular polymeric substances),which could promote the biodegradation of hydrocarbons. The increase of biofilm followed first-order kinetics with rate of 0.216 μg glucose/(cm~2·day) in logarithm phase. With analysis of Fourier transform infrared spectroscopy (FT-IR) and gas chromatography-mass spectrometry (GC-MS) combined with removal of lube oil and TDOC, mixed bacterial consortium could degrade benzene and its derivatives, aromatic ring organic matters with a percentage over 97%.     

絮凝剂产生菌Geotrichum candidum的絮凝特性研究

本文研究了活性污泥中分离出的絮凝剂产生菌J-5的絮凝特性。通过形态学、理化特征、18SrDNA序列和G+C含量研究,鉴定J-5为Geotrichum candidum。培养3d,G.candidum的生长量达到最高,但其絮凝活性在1d培养后即达到最大值。絮凝活性分布研究表明G.candidum的胞外分泌物是起主要絮凝作用的物质。培养液的上层清液通过乙醇沉淀和去离子水渗析后得到粗制生物絮凝剂。利用化学分析、紫外分析和红外分析研究生物絮凝剂的化学组成,发现其主要由多糖构成,其中占主要成分的是中性糖和糖醛酸,生物絮凝剂分子含羟基、羧基和甲氧基官能团。     

Positive remediation on sedimentary P by combination of capping with calcium hydroxide and oxidation with perhydrol

The capping is called passive remediation because the sedimentary P was released and then immobilized by the capping materials. However, the release depends on the environmental conditions. Therefore, a hypothesis was proposed that the oxidant was used to accelerate sedimentary P release and the capping material was used to capture those released P. It is positive remediation to reduce sedimentary P amount. The results show that soluble reactive phosphorus（SRP） concentration in the overlying wat...     

利用秸秆微生物产絮凝剂的提取及性质分析

文章对一株利用秸秆粉——无机氮源培养基的细菌所产生的微生物絮凝剂进行了粗提和性质分析。该絮凝剂对于高岭土——氯化钙悬浊液的絮凝率达93.96%,效果较好。将该细菌接种在液体培养基中,于恒温摇床发酵培养,经测定,主要絮凝成分位于发酵液上清液中,对发酵液上清液进行热稳定性和pH稳定性实验,结果表明,该絮凝剂在室温25℃、pH为7条件下絮凝效果最好。采用乙醇法对发酵液上清液进行提取,即可得该微生物絮凝剂粗品。经Molish反应及茚三酮反应显色可知,该絮凝剂含有糖类及蛋白成分,经苯酚硫酸法测定其中糖含量占湿重的11.666%,经考马斯亮蓝法测定其中蛋白含量占湿重的0.586 4%,经薄层层析分析得,该微生物絮凝剂含有的主要糖类成分为阿拉伯糖。     

Isolation of antifungal bacteria from Japanese fermented soybeans,natto

An inhibitory effect of a traditional Japanese fermented food, natto, was found against plant pathogens such as Rhizoctonia solani and Fusarium oxysporum, and the bacteria which showed inhibition were isolated from the natto. Among isolated bacteria, BC-1 and GAc exhibited a strong antagonistic effect in vitro against plant pathogens on an agar medium. The supernatant of bacterial culture also showed strong activity against R. solani, which meant the antimicrobial substances were produced and secreted into the medium. Both of the bacteria were estimated as Bacillus amyloliquefaciens from a partial sequence of the 16s rRNA gene. High performance liquid chromatography analysis clearly showed the production of the lipopeptide antibiotic iturin A by BC-1 and GAc.     

一株DEHP降解菌的筛选和分子鉴定

采用富集培养法从污水厂活性污泥中分离得到一株能以邻苯二甲酸二(2-乙基己基)酯(DEHP)为唯一碳源的细菌。该菌在48 h内可将DEHP浓度从20 mg/L降解到2 mg/L。对其进行了生理生化试验和分子生物学鉴定。结果表明,该菌株呈丝状,革兰氏阳性,好氧,能在45℃下生长。该菌株与长孢糖丝菌模式菌Saccharothrix longispora DSM 43749在同一分枝上,同源性为98.9%;与糖丝菌属(Saccharothrixsp)内其他种同源性均在97.0%以上。     

Isolation of antifungal bacteria from Japanese fermented soybeans, natto

An inhibitory effect of a traditional Japanese fermented food, natto, was found against plant pathogens such as Rhizoctonia solani and Fusarium oxysporum, and the bacteria which showed inhibition were isolated from the natto. Among isolated bacteria, BC-1 and GAc exhibited a strong antagonistic effect in vitro against plant pathogens on an agar medium. The supernatant of bacterial culture also showed strong activity against R. solani, which meant the antimicrobial substances were produced and secreted into the medium. Both of the bacteria were estimated as Bacillus amyloliquefaciens from a partial sequence of the 16s rRNA gene. High performance liquid chromatography analysis clearly showed the production of the lipopeptide antibiotic iturin A by BC-1 and GAc.     

利用铁改性方解石作为活性覆盖材料控制水体内源磷的释放

虽然利用方解石作为一种活性覆盖材料控制水体内源磷释放具有较好的应用前景,但是其控制底泥中磷释放的效率仍然有待进一步提高.鉴于此,本文采用铁盐对方解石进行改性试图制备一种除磷性能更好的底泥活性覆盖材料——铁改性方解石,进而通过批量实验考察了铁改性方解石对水中磷酸盐的去除性能,以及通过底泥培养实验考察了铁改性方解石活性覆盖控制水体内源磷释放的效率.结果发现,采用铁对方解石进行改性,可以显著提高材料对水中磷酸盐的去除能力.铁改性方解石投加量的增加,有利于水中磷酸盐的去除.增加初始磷浓度,铁改性方解石对水中磷酸盐的单位去除量随之增加,最大的单位磷去除量可以达到3.09 mg·g~(-1).铁改性方解石覆盖可以有效地控制底泥中磷的释放,导致上覆水体中溶解态活性磷(SRP)浓度处于很低的水平.此外,铁改性方解石覆盖还可以促使底泥中少量的氧化还原敏感态磷(BD-P)和金属氧化结合态磷(NaOH-rP)向残渣态磷(Res-P)转变,使得底泥中磷的稳定性略微增强.固定到铁改性方解石覆盖层中的磷大多数(90.8%)以较为稳定和非常稳定的形态存在,且大部分磷以非生物可利用性磷形式存在,很难被重新释放出来.与方解石覆盖相比,铁改性方解石覆盖控制底泥中磷向上覆水体中释放的效率明显更高,且被铁改性方解石覆盖层所钝化的磷更为稳定.以上结果显示,铁改性方解石是一种非常有希望用于控制水体内源磷释放的底泥活性覆盖材料.     

低能离子诱变产表面活性剂的烃降解菌研究

为有效治理石油污染土壤,从长期遭受石油污染的土壤中筛选出一株烃降解菌8-11作为出发菌,利用低能N+注入烃降解菌进行诱变,在能量为20 keV、剂量为90×2.6×1013ions/cm2条件下筛选出一株高效烃降解菌——诱变菌23。原油摇瓶发酵实验表明诱变菌对原油的降解率达到74%;降解后原油的全烃气相色谱图显示,经过7 d的作用,原油中的正构烷烃完全降解。诱变菌23能够产生大量的生物表面活性物质,傅里叶红外光谱分析表明其产生的生物活性物质为糖脂类化合物,该糖脂类生物表面活性剂能使发酵液的表面张力从空白对照的56.1 mN/m降低为29.3 mN/m。研究表明诱变菌23具有较高的烃降解能力,能有效降低表面张力,具有较大的应用潜力。     

Evaluating the effectiveness of marine actinobacterial extract and its mediated titanium dioxide nanoparticles in the degradation of azo dyes

Aim of the present study was to synthesize titanium dioxide nanoparticles （YiO2 NPs） from marine actinobacteria and to develop an eco-friendly azo-dye degradation method. A total of five actinobacterial isolates were isolated from Chennai marine sediments, Tamilnadu, India and analyzed for the synthesis of TiO2 NPs using titanium hydroxide. Among these, the isolate PSV 3 showed positive results for the synthesis of TiO2 NPs, which was confirmed by UV analysis. Further characterization of the synthesized TiO2 NPs was done using XRD, AFM and FI＇-IR analysis. Actinobacterial crude extract and synthesized TiO2 NPs was found efficient in degrading azo dye such as Acid Red 79 （AR-79） and Acid Red 80 （AR-80）. Degradation percentage was found to be 81% for AR-79, 83% for AR-80 using actinobacterial crude extract and 84% for AR-79, 85% for AR-80 using TiO2 NPs. Immobilized actinobacterial ceils showed 88% for AR-79 and 81% for AR- 80, dye degrading capacity. Degraded components were characterized by FT-IR and GC-MS analysis. The phytotoxicity test with 500 μg/mL of untreated dye showed remarkable phenotypic as well as cellular damage to Tagetes erecta plant. Comparatively no such damage was observed on plants by degraded dye components. In biotoxicity assay, treated dyes showed less toxic effect as compared to the untreated dyes.     

纳米磁粉复配混凝剂深度处理木薯酒精废水研究

将纳米Fe_3O_4颗粒与无机混凝剂FeCl_3复配,用于木薯酒精废水的强化混凝处理;探索了磁复配前后混凝剂的除浊、除有机物和脱色效果,并对絮体和出水分别进行了红外和三维荧光光谱分析。结果表明:相较于普通FeCl_3,磁复配混凝剂的浊度去除率达98.5%,除浊效果有明显提高;而溶解性有机物和致色物质的去除主要依赖于FeCl_3的作用,由于木薯酒精好氧处理出水存在木质素分解产物和类黑精,大量羟基和酰胺键易与Fe~(3+)形成金属配位键。     

氧化锌纳米颗粒对膜-生物反应器运行性能的影响

考察了城市污水中典型浓度的氧化锌(ZnO)纳米颗粒对膜-生物反应器(MBR)运行、活性污泥性质以及膜污染的影响.结果表明,ZnO纳米颗粒不利于微生物对有机物的去除,但是不会影响微生物对氨氮的去除.由于微滤膜的截留作用,ZnO纳米颗粒对MBR的出水没有影响.ZnO纳米颗粒的投加导致溶解性微生物产物(SMP)浓度从17.9mg/gVSS上升到35.0mg/gVSS左右,污泥粒径由162.9μm下降到105.2μm,引起了外部阻力的上升,造成了膜污染的加剧.ZnO纳米颗粒会抑制微生物活性和改变活性污泥中微生物的种群结构,这主要与ZnO纳米颗粒释放的Zn2+有关.     

原位掩蔽对底泥汞释放的抑制效果及中试评估

为解决贵州省百花湖底泥中的汞污染问题,研究了原位掩蔽对底泥中汞释放的抑制效果. 选择沸石、高岭土和赤铁矿为掩蔽材料,通过模拟试验,确定原位掩蔽的最佳覆盖厚度为2.0 cm,此时沸石、高岭土和赤铁矿对底泥汞释放的控制率分别为47.1%、64.9%和62.3%,说明最佳掩蔽材料为高岭土. 以高岭土为掩蔽材料的情况下,试验实施7 d后,水体扰动对控制率的影响不足6.7%. 中试区位于百花湖重度污染区,面积约为22 000 m2,采用驳船少量多次撒布高岭土原位掩蔽汞污染底泥,控制覆盖厚度为2.0~3.0 cm,按月连续监测6次. 结果显示,高岭土对汞污染底泥的控制率达到47.1%. 模拟试验及中试效果显示,高岭土原位掩蔽可有效抑制底泥中汞的释放,并且较薄的覆盖厚度可降低工程成本和对湖底生态系统的影响.      

Bioleaching of spent Ni-Cd batteries and phylogenetic analysis of an acidophilic strain in acidified sludge

Biohydrometallurgy is a novel method to recycle discarded batteries, in which sewage sludge is used as microorganisms and culture due to the presence of indigenous Thiobacilli. A two-step continuous flow leaching system consisting of an acidifying reactor and a leaching reactor was introduced to achieve the bioleaching of spent nickel-cadmium (Ni-Cd) batteries. The acid supernatant produced in the acidifying reactor by the microorganisms with ferrous ions as the substrate was conducted into the leaching reactor to dissolve electrode materials. The efficiency of a batch treatment of batteries was examined. The results showed that the complete dissolution of two AA-sized Ni-Cd batteries with 0.6 L/d acid supernatant took about 30, 20, and 35 days for Ni, Cd, and Co, respectively. But the dissolution ability of the three metals was different. Cd and Co can be leached mostly for pH below 4.0 while the complete dissolution of Ni can be achieved for pH below 2.5. Meanwhile, a strain (named Thiooxidans. WL) accounting for the reduction of pH in the acidified sludge was isolated and sequenced. It was identified to be 100% similar to Acidithiobacillus ferrooxidans strain Tf-49 based on 16S rDNA sequence analysis. The relevant phylogenetic tree constructed indicates that the strain should be classified into genus Acidithiobacillus ferrooxidans.