玉米秸秆和白菜废弃物在不同贮存条件下的微生物群落北大核心CSCD

采用Illumina Miseq高通量技术分析不同温度和贮存方式下玉米秸杆（IO）和白菜废弃物（IA）贮存30 d时的微生物群落. 设置低温（O）、中温（R）和高温（H）3种温度;每种温度条件均设有秸杆单贮（O）、白菜单贮（A）和二者混贮（X）3个处理组. 结果显示,IO原料附着细菌主要包括变形菌门（Proteobacteria）（65.26%）和厚壁菌门（Firmicutes）（33.78%）,IA主要包括Proteobacteria（80.23%）和拟杆菌门（Bacteroidetes）（18.57%）. 贮存30 d后在属水平上,IO主要包括肠杆菌（Enterobacter）（47.11%）、肉食杆菌（Carnobacterium）（27.71%）和泛菌（Pantoea）（10.14%）等;IA主要包括假单孢菌（Pseudomonas）（48.40%）、Pantoea（17.10%）和黄杆菌（Flavobacterium）（16.26%）等;IA中几乎不含乳酸菌,IO中乳酸菌丰度约28.71%. IO组低、高温单贮时主要包括Enterobacter（21.76%和35.87%）、Carnobacterium（40.42%和27.29%）和Pseudomonas（18%和26.99%）,中温单贮时主要包括Enterobacter（66.72%）;IA中、高温单贮时主要包括乳杆菌（Lactobacillus）（80.07%和74.63%）,低温单贮时主要包括Lactobacillus（28.43%）、耶尔森氏鼠疫杆菌（Yersinia）（19.50%）和Enterobacter（17.13%）;二者低、中温混贮时主要包括Lactobacillus（52.03%和53.52%）、Enterobacter（5.98%和11.65%）和Carnobacterium（12.98%和10.65%）,高温混贮时主要包括Enterobacter（70.57%）. 综上表明,高通量测序技术全面反映了IO和IA在不同贮存条件下细菌群落的组成及丰度信息,白菜中高温单独贮存、秸秆/白菜中低温混合贮存时乳酸菌占优势. （图9 表3 参37）     

新型多孔高分子载体厌氧流化床启动实验研究

制备了两种不同孔径（ｄ＞０．５μｍ）分率的聚丙烯酸酯类多孔载体，与多孔颗粒活性炭（ＧＡＣ）在完全相同的启动条件下，作厌氧流化床固定化微生物对比实验．结果表明：新型高分子载体能有效促进厌氧菌固定化速度，可比ＧＡＣ缩短反应器启动时间１５ｄ左右；扫描电镜观察发现，多孔高分子生物颗粒球形度高，表面生物膜致密坚实，内孔微生物聚集丰富，而ＧＡＣ生物颗粒形状不规则，表面生物膜疏松呈鳞片状，内孔不易驻留微生物．另外，根据高分子载体内孔产甲烷丝菌的形态和分布特征，获取了当生物膜持续增厚后（δ＞１００μｍ），基质扩散阻力影响内孔微生物活性的证据．     

不同补给水源的城市人工湖中异养菌耐药性及耐药菌种属分布研究

为了阐明不同补给水源的城市人工湖中异养菌耐药状况和耐药菌种属分布特征,选取分别以地表水和再生水为补水来源的XQ湖和FQ湖为代表进行研究。从2018年4—11月逐月采集水样,考察了各水样中对氨苄西林(AMP)、磺胺甲恶唑(SMZ)和四环素(TET)这3种不同种类抗生素具有耐药性的异养菌含量,并对分离菌株的耐药表型、耐药菌株的种属分布以及水质理化指标进行了分析。结果表明,2处人工湖中的AMP耐药菌和SMZ耐药菌含量约为10~2～10~4CFU·(100 m L)~(-1),而TET耐药菌含量则约10~1～10~3CFU·(100 m L)~(-1)。分离出的84株耐药菌归属于19个种,其中蜡状芽孢杆菌、大肠埃希氏菌、维氏气单胞菌、豚鼠气单胞菌和鸟氨酸拉乌尔菌为2个湖共有耐药菌。71.4%的耐药菌都是对AMP单一耐药,以蜡状芽孢杆菌为主。由于具有固有耐药性的细菌在分离出的耐药菌中占比很低,获得性耐药很可能在城市人工湖中异养菌耐药性的发展上发挥了主要贡献作用。地表水补水的XQ湖和再生水补水的FQ湖在总异养菌含量、耐药菌含量和检出率上均无显著差异。分离来源对16株耐药性气单胞菌的聚类无明显影响。     

微塑料生物膜11种AHLs类群体感应信号分子测定及其分泌特征

为研究微塑料生物膜的群体感应效应,利用液液萃取和超高效液相色谱-串联质谱技术,建立了微塑料上枯草芽孢杆菌生物膜分泌的11种酰基高丝氨酸内酯(AHLs)类群体感应信号分子前处理和仪器分析方法.优化后的前处理方法采用酸化的乙酸乙酯(0.01％冰乙酸,V/V)对微塑料生物膜样品中AHLs类信号分子进行萃取,萃取方式采用冰浴超...     

再生水灌溉对冬小麦生长和产量的影响

随着我国污水处理技术的发展,再生水生产能力得到了明显地提高,实现再生水农业安全利用,将开辟农业用水新途径。以冬小麦（Triticum aestivum）为对象,通过盆栽试验,研究了不同程度处理的再生水（二级再生水、三级再生水）对冬小麦生长和产量的影响。结果表明：再生水灌溉能显著提高冬小麦的株高、叶面积、叶绿素含量,但开花前对光合作用的改善不显著。再生水灌溉处理的冬小麦超氧化物歧化酶（SOD）活性整体提高,尤其是越冬阶段,叶片SOD活性较对照处理提高了15%,抽穗后作用减弱,各处理间的过氧化物酶（POD）活性差异不明显。以再生水灌溉的盆栽小麦产量和对照相比没有明显差异,再生水灌溉可以实现正常的产量水平。     

不同生物膜附着微塑料对文蛤鳃的毒性效应

近年来,微塑料在海洋环境中的广泛分布及其生物毒性效应与健康风险备受关注。天然海洋环境中,微塑料表面易被多种微生物定殖并形成生物膜,这可能影响微塑料的生物毒性,然而目前对其影响仍知之甚少。以海南典型双壳贝类文蛤（Meretrix lyrata）为受试动物,并以其重要的呼吸和滤食器官鳃为靶器官,研究生物膜对微塑料生物毒性的影响。通过将文蛤暴露在质量浓度为100μg·L-1的不同类型原始和生物膜附着的微塑料（聚苯乙烯PS、聚乙烯PE、聚对苯二甲酸乙二醇酯PET）环境中14 d,研究微塑料在文蛤鳃中的富集特征及其对鳃组织的病理损伤、抗氧化及免疫防御系统相关指标的影响。结果表明,原始和生物膜附着微塑料均能在文蛤鳃组织中富集,富集量随暴露时间延长而增加,且生物膜附着微塑料的生物富集效应更显著;微塑料富集导致鳃组织发生不同程度的机械损伤,出现鳃丝粘连、萎缩及断裂、鳃丝细胞坏死、纤毛脱落等病理现象,其中附着生物膜的微塑料比原始微塑料对鳃显微结构的损伤更为明显;微塑料胁迫造成超氧化物歧化酶（SOD）、过氧化氢酶（CAT）和碱性磷酸酶（ALP）活性升高,谷胱甘肽（GSH）含量下降,丙二醛（MDA）含量无显...     

重金属-柠檬酸-针铁矿三元体系的表面络合模型研究

根际环境产生的柠檬酸等小分子有机酸可能影响重金属的溶出效应.本文研究了4种重金属Cd、Pb、Cu、Ni及柠檬酸在针铁矿表面的三元体系吸附行为,结果发现柠檬酸促进了4种重金属酸性条件下在针铁矿表面的吸附量,而Cu、Ni促进了柠檬酸碱性条件下的吸附.结合红外光谱图发现,重金属-柠檬酸-针铁矿主要存在以下2种三元体系形态,即以柠檬酸为"桥键"的≡Fe2CitMe形态和以重金属为"桥键"的(≡FeOH)2MeCit形态.采用电荷分配-多位点表面配合(CD-MUSIC)模型成功预测了的三元体系重金属及柠檬酸在针铁矿表面的吸附行为,模型结果发现柠檬酸的存在显著改变了重金属的吸附形态,其中≡Fe2CitMe为Cd、Pb、Ni三元体系中酸性条件下的主要形态,(≡FeOH)2CuCit为Cu的主要形态.研究补充完善了根际环境的土壤形态模型数据库,为预测重金属的溶出及生物有效性的模型研究提供了基础数据.     

利用PCR-DGGE技术分析乳制品中的乳酸菌

在食品发酵行业,需要一种简捷有效的方法检测发酵产品中的有益微生物.聚合酶链式反应-变性梯度凝胶电泳(Ploymerase chain reaction and denaturing gredient gel electrophoresis,PCR-DGGE)技术广泛应用于微生物生态学的研究.采用PCR-DGGE对5种含有乳酸菌的乳制品进行了菌群组成分析,并通过传统培养方法和核酸序列分析进行了验证.结果表明,所有测试样品中的活菌数量都在106～109 cfu/mL之间,通过平板培养法分离出了形态明显的杆状菌和链球状菌,对其进行16S rDNA核酸序列测定及同源性分析,将其鉴定为德氏乳杆菌(Lactobacillus delbrueckii)和嗜热链球菌(Streptococcus thermophilus).建立了由已知乳酸菌组成的DGGE参考阶梯(Reference ladder),可用其对相应菌株进行DGGE鉴定.用两对不同引物进行PCR-DGGE分析,除样品1外,试样中均检测到德氏乳杆菌和嗜热链球菌.对DGGE参考阶梯未能直接鉴定的样品1的电泳条带进行同收、序列分析,分别鉴定为卷曲乳杆菌(L.crispatus)和鼠李糖乳杆菌(L.rhamnosus).同时发现,引物R518-F357对嗜热链球菌模板的识别效率高于引物Lac1GC-HDA2.以上结果表明,RCRDGGE技术可以对样品中的乳酸菌进行快速的分析和鉴定.图4表1参30     

阳离子表面活性剂对沉积物及其主要组分吸附双酚A的影响

采用吸附实验、选择性萃取技术研究阳离子表面活性剂-十六烷基三甲基溴化铵(CTMAB)对表层沉积物(生物膜)吸附双酚A(BPA)的影响规律,及CTMAB不同加入条件下对表层沉积物(生物膜)选择性萃取(铁氧化物、锰氧化物、有机质)后的组分吸附BPA的影响.CTMAB对表层沉积物(生物膜)吸附BPA起到促进作用,且随着CTMAB浓度的增加,其促进作用增强;CTMAB掺杂顺序对表层沉积物吸附BPA的影响较小,但对生物膜吸附BPA的影响较大;CTMAB的引入导致BPA在选择性萃取后的表层沉积物(生物膜)组分上的吸附量显著增加,并且CTMAB对表层沉积物(生物膜)吸附BPA的促进作用远大于表层沉积物(生物膜)自身主要组分理化性质的影响.选择性萃取证明,阳离子表面活性剂的引入能降低BPA在水体环境中的迁移转化能力.     

两种生物农药对土壤蔗糖酶活性的影响

采集海南省儋州市国家热带农业高新技术示范园土样中农田土样,在分析土壤基本理化性质的基础上,用3,5-二硝基水杨酸比色法测定法.研究了不同模拟条件下苏云金杆菌、井冈霉素A对土壤蔗糖酶活性的影响.结果表明:不同浓度、pH条件下这两种生物农药对土壤蔗糖酶表现出不同程度的激活作用.在30 d的培养时间内,苏云金杆菌(bacillus thuringiensis)对土壤蔗糖酶活性影响的趋势是激活→抑制→恢复,而且波动范围较大;井岗霉素A(jinggangmycin A)对土壤蔗糖酶活性影响程度相对较小,总的趋势是激活→抑制.总体来看,施用这两种生物农药有利于提高土壤蔗糖酶的活性.     

Effect of biological activated carbon filter depth and backwashing process on transformation of biofilm community

We studied BAC biofilm during the process of initial operation and backwash. Microbial diversity decreased gradually with the increase of BAC filter depth. Proteobacteria dominated at the phylum level among the BAC biofilm samples. α-proteobacteria increased about 10% in all carbon filter depth after backwash. The biological activated carbon (BAC) is a popular advanced water treatment to the provision of safe water supply. A bench-scale device was designed to gain a better insight into microbial diversity and community structure of BAC biofilm by using high-throughput sequencing method. Both samples of BAC biofilm (the first, third and fifth month) and water (inlet water and outlet water of carbon filter, outlet water of backwashing) were analyzed to evaluate the impact of carbon filter depth, running time and backwash process. The results showed that the microbial diversity of biofilm decreased generally with the increase of carbon filter depth and biofilm reached a steady-state at the top layer of BAC after three months’ running. Proteobacteria (71.02%–95.61%) was found to be dominant bacteria both in biofilms and water samples. As one of opportunistic pathogen, the Pseudomonas aeruginosa in the outlet water of device (1.20%) was about eight times higher than that in the inlet water of device (0.16%) at the genus level after five-month operation. To maintain the safety of drinking water, the backwash used in this test could significantly remove Sphingobacteria (from 8.69% to 5.09%, p<0.05) of carbon biofilm. After backwashing, the operational taxonomic units (OTUs) number and the Shannon index decreased significantly (p<0.05) at the bottom of carbon column and we found the Proteobacteria increased by about 10% in all biofilm samples from different filter depth. This study reveals the transformation of BAC biofilm with the impact of running time and backwashing.     

Improvement of the assimilable organic carbon (AOC) analytical method for reclaimed water

Microbial growth is an issue of concern that may cause hygienic and aesthetic problems during the transportation and usage of reclaimed water. Assimilable organic carbon (AOC) is an important parameter which determines the heterotrophic bacterial growth potential of water. Pseudomonas fluorescens P17 and Spirillum sp. NOX are widely used to measure AOC in drinking water. The AOC values of various reclaimed water samples determined by P17 and NOX were compared with those determined by the new strains isolated from reclaimed water in this study. It showed that the conventional test strains were not suitable for AOC measurement of reclaimed water in certain cases. In addition to P17 and NOX, Stenotrophomonas sp. ZJ2, Pseudomonas saponiphila G3 and Enterobacter sp. G6, were selected as test strains for AOC measurement of reclaimed water. Key aspects of the bioassay including inoculum cell density, incubation temperature, incubation time and the pH of samples were evaluated for the newly selected test strains. Higher inoculum density (10⁴ CFU·mL^-1) and higher incubation temperature (25°C) could reduce the time required for the tests. The AOC results of various collected samples showed the advantages of the method proposed based on those five strains in evaluating the biologic stability of reclaimed water.     

城市回用水中多环芳烃致癌风险评价

为评价人群暴露于城市回用水中16种多环芳烃(polycyclic aromatic hydrocarbons,PAHs)对于人体健康的潜在风险,采用气相色谱-质谱(GC-MS)联用的分析化学方法对不同季节回用水中16种PAHs进行定量分析;在此基础上采用美国国家科学院和国家研究委员会提出的环境健康风险评价方法,分析不同回用条件下具有中国水体基质特色的城市回用水中PAHs健康风险.结果显示,回用水样中16种PAHs的总浓度为1 422.85 ng·L-1,污水处理厂二级出水水样16种PAHs的总浓度为1 791.77 ng ·L-1,经过处理后回用水中PAHs含量有所降低.风险评价分析结果显示,回用水在城市绿化、农业灌溉和景观娱乐3种不同回用途径下多环芳烃的致癌风险分别为788×10-8、2.77×10-6、3.04×10-6,总致癌风险为5.89×10-6.以上结果可以得出,回用水在城市绿化、农田灌溉和景观娱乐接触过程中多环芳烃所增加的致癌风险很低,回用水中多环芳烃的健康风险处于可接受水平.     

Effect of the ultraviolet/chlorine process on microbial community structure,typical pathogens,and antibiotic resistance genes in reclaimed water

• UV/chlorine can effectively remove VBNC pathogens, ARGs and MGEs in reclaimed water. • Microbial community was changed with reduced diversity during UV/chlorine process. • CRBs-carried MGEswere the predominant groups during UV/chlorine process. • No direct co-selection strategy was shared between UV/chlorine and resistome. Urban wastewater contains a wide range of pathogens and antibiotic resistance genes (ARGs), which are a serious concern if reusing treated wastewater. However, few studies have explored the microbial communities in reclaimed water using ultraviolet (UV)/chlorine treatment and assessed the changes of the resistome. This study investigated the occurrence of typical pathogens, ARGs, and bacterial communities in UV/chlorine-treated reclaimed water samples. The numbers of culturable and viable but non-culturable pathogens were effectively reduced to 0 CFU/mL within 1–10 and 10–30 min after UV/chlorine treatment, respectively. Meanwhile, the physicochemical indices of water quality were not affected. UV/chlorine treatment could significantly change the bacterial community structure of reclaimed water, showing a decrease in bacterial abundance and diversity. Chlorine-resistant Acinetobacter and Mycobacterium were the dominant bacterial genera (>50%) after UV/chlorine treatment. Moreover, the number of ARGs and mobile genetic elements (MGEs) decreased with an increase in UV/chlorine exposure. However, eight ARGs and three MGEs were consistently detected in more than three seasons, making these major concerns because of their potential role in the persistence and dissemination of antibiotic resistance. Overall, the results of this study suggest that UV/chlorine treatment can potentially improve the microbiological safety of reclaimed water. And more attention should be paid to the pathogens that are both chlorine-resistant and carry MGEs because of their potential for resistance transmission.     

Determination of 27 pharmaceuticals and personal care products (PPCPs) in water: The benefit of isotope dilution

• Isotope dilution method was developed for the determination of 27 PPCPs in water. • The established method was successfully applied to different types of water samples. • The correction effect of corresponding 27 ILSs over 70 d was investigated. • Benefit of isotopic dilution method was illustrated for three examples. Pharmaceuticals and personal care products (PPCPs) are a unique group of emerging and non-persistent contaminants. In this study, 27 PPCPs in various water samples were extracted by solid phase extraction (SPE), and determined by isotope dilution method using liquid chromatography coupled to tandem triple quadruple mass spectrometer (LC-MS/MS). A total of 27 isotopically labeled standards (ILSs) were applied to correct the concentration of PPCPs in spiked ultrapure water, drinking water, river, effluent and influent sewage. The corrected recoveries were 73%–122% with the relative standard deviation (RSD)<16%, except for acetaminophen. The matrix effect for all kinds of water samples was<22% and the method quantitation limits (MQLs) were 0.45–8.6 ng/L. The developed method was successfully applied on environmental water samples. The SPE extracts of spiked ultrapure water, drinking water, river and wastewater effluent were stored for 70 days, and the ILSs-corrected recoveries of 27 PPCPs were obtained to evaluate the correction ability of ILSs in the presence of variety interferences. The recoveries of 27 PPCPs over 70 days were within the scope of 72%–140% with the recovery variation<37% in all cases. The isotope dilution method seems to be of benefit when the extract has to be stored for long time before the instrument analysis.     

Hydraulic model for multi-sources reclaimed water pipe network based on EPANET and its applications in Beijing, China

Water shortage is one of the major water related problems for many cities in the world. The planning for utilization of reclaimed water has been or would be drafted in these cities. For using the reclaimed water soundly, Beijing planned to build a large scale reclaimed water pipe networks with multi-sources. In order to support the plan, the integrated hydraulic model of planning pipe network was developed based on EPANET supported by geographic information system (GIS). The complicated pipe network was divided into four weak conjunction subzones according to the distribution of reclaimed water plants and the elevation. It could provide a better solution for the problem of overhigh pressure in several regions of the network. Through the scenarios analysis in different subzones, some of the initial diameter of pipes in the network was adjusted. At last the pipe network planning scheme of reclaimed water was proposed. The proposed planning scheme could reach the balances between reclaimed water requirements and reclaimed water supplies, and provided a scientific basis for the reclaimed water utilization in Beijing. Now the scheme had been adopted by Beijing municipal government.     

Performance of a hybrid anaerobic-contact oxidation biofilm baffled reactor for the treatment of decentralized molasses wastewater

A novel hybrid anaerobic-contact oxidation biofilm baffled reactor （HAOBR） was developed to simultaneously remove nitrogenous and carbonaceous organic pollutants from decentralized molasses wastewater in the study. The study was based on the inoculation of anaerobic granule sludge in anaerobic compartments and the installation of combination filler in aerobic compartments. The performance of reactor system was studied regarding the hydraulic retention time （HRT）, microbial characteristics and the gas water ratio （GWR）. When the HRT was 24h and the GWR was 20：1, total ammonia and chemical oxygen demand （COD） of the effluent were reduced by 99% and 91.8%, respectively. The reactor performed stably for treating decentralized molasses wastewater. The good performance of the reactor can be attributed to the high resistance of COD and hydraulic shock loads. In addition, the high solid retention time of contact oxidation biofilm contributed to stable performance of the reactor.     

管网生物膜菌株胞外聚合物的提取方法比较

以饮用水管网生物膜样品中一株强成膜能力的菌株Pleomorphomonas oryzae作为研究对象,考察了8种方法(高速离心法、超声法、加热法、EDTA法、H2SO4法、NaOH法、SDS法、甲醛法)对菌株胞外聚合物(EPS)的提取效果,并结合三维荧光光谱(EEM)和傅立叶红外光谱(FTIR)对提取的EPS进行成分分析.结果表明,EDTA法和H2SO4法既能提高EPS的提取效率,提取量分别为64.77 mg.g-1SS和74.43 mg.g-1SS,是离心方法提取量的1.62倍和1.86倍,又不会在提取过程中对菌株细胞造成破坏,是较为理想的EPS提取方法.EEM分析进一步证实,NaOH法对菌株细胞破坏严重,造成EPS成分变化较大.FTIR分析则说明,化学提取方法相较于物理提取方法会引入杂质对组分测定造成干扰.     

生物膜及其组分对4-氯酚的吸附速率研究

研究了４－氯酚在生物膜不同组分上的吸附速率特征．本实验中生物膜不同组分包括生长有生物膜外壳的模拟水体悬浮颗粒物(高岭土)、细菌细胞、胞外多糖、高岭土及有胞外多糖存在的高岭土５个部分．结果表明,生物膜及其不同组分均对４－氯酚发生吸附,以细菌细胞更为显著,但它们的时间动力学过程不同． 在所研究的５种吸附体系中,生长有生物膜外壳的高岭上体系较快地达到近平衡状态．并且吸附时间过程受ｐＨ值的影响．     

序批式膜反应器处理高氨氮渗滤液同步硝化反硝化特性

应用序批式生物膜反应器(SBBR)处理实际垃圾渗滤液,在DO浓度分别为0.45mg.l-1和1.19mg.l-1条件下,研究了系统的有机物,氨氮和总氮去除特性以及游离氨(FA),DO对系统同步硝化反硝化(SND)类型的影响.250d试验研究表明:SBRR系统能够稳定高效地同步去除渗滤液内高浓度有机物和高浓度氨氮.在初始COD浓度为122—2385 mg.l-1的情况下,出水COD浓度为23—929 mg.l-1,有机物最大去除速率25.6 kgCOD.m-2载体.d-1.在初始NH4+-N浓度为40—396.5 mg.l-1的情况下,出水NH4+-N浓度为0—41.2 mg.l-1,最大硝化速率2.87 kgN.m-2载体.d-1.SBBR系统内发生了明显的同步硝化反硝化(SND)现象,TN平均去除率分别为73.8%(DO=0.45 mg.l-1)和30%(DO=1.19 mg.l-1)左右.当FA浓度在1.5—11.6 mg.l-1范围内时,系统中共存硝酸型SND和亚硝酸性SND.当FA从18.6 mg.l-1增加到56 mg.l-1,系统中形成稳定的亚硝酸SND.因此,FA是影响系统SND类型的主要因素,DO可促进亚硝酸性SND向硝酸型SND转化.