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1.
竹醋对生活污水好氧处理的强化作用初步研究 总被引：1，自引：0，他引：1
采用在生活污水好氧处理之前投加外源物质的方法 ,研究了竹醋 (Bamboo Vinegar,BV)及其主要有机成分 (乙酸 )对污水好氧处理效果的强化作用。结果表明 :1当 VBV/ V污水 的比值达到1 / 1 0 6时 ,BV对污水 CODcr的去除有极显著的强化作用 :CODcr去除率比不加竹醋的对照组提高1 0 %。但是 ,BV对污水中 NH+ 4 - N,T- P的去除率没有影响。 2乙酸单独使用亦可显著提高污水CODcr去除率 ,当 V乙酸 / V污水 为 1 / 1 0 7时 ,强化效果最好 ,CODcr去除率提高 1 3%。由于乙酸具有与BV相似的作用特点 ,所以认为 BV对污水处理效果的强化作用来自其中的乙酸。为了将 BV应用于污水处理中 ,需要进一步研究确定 BV对活性污泥法、生物膜法处理污水的强化效果 相似文献
2.
ZHU Yanbing LIU Guangming LI Hebin LIU Jingwen BAI Xiaoming GUAN Rong CAI Huinong 《海洋学报(英文版)》2012,31(6):117-126
The gene(741 bp) encoding carboxylesterase from the thermophilic bacterium Geobacillus sp.ZHl was cloned and overexpressed in Escherichia coli.The purified recombinant protein presented a molecular mass of about 40 kDa by SDS-PAGE analysis.Enzyme assays using p-nitrophenyl esters with different acyl chain lengths as the substrates confirmed its esterase activity,yielding highest specific activity with p-nitrophenyl acetate.Among the p-nitrophenyl esters tested,the carboxylesterase presented preference for p-nitrophenyl caprylate,but hydrolyzed p-nitrophenyl butyrate more efficiently.When p-nitrophenyl butyrate was used as a substrate,the recombinant carboxylesterase exhibited highest activity at pH 8.0 and 60℃.Almost no decrease in esterase activity was observed at 60℃for 3 h,and over 40% of activity was still maintained after incubation at 90℃for 3 h.These results indicate that Geobacillus sp.ZH1 recombinant esterase was thermostable.The enzymatic activity was inhibited by the addition of phenylmethylsulfonyl fluoride,indicating that it contains serine residue,which plays a key role in the catalytic mechanism.Except SDS and xylene,this esterase showed stability toward other tested detergents and organic solvents.Cloning,expression,and biochemical characterization of Geobacillus sp.ZH1 carboxylesterase lay a good foundation for its structural characterization and industrial application. 相似文献
3.
Microbes are believed to play important roles in ecosystem function in many environments. The hot springs of Xiamen Island are close to the Xiamen Sea, and may have some characteristics different from those of inland hot springs. Microbes living in the hot springs of Xiamen may have new characteristics. However, little is known about microbial communities of hot springs close to the Xiamen Sea. A cuhure-dependent survey of microbial population in the Xiamen hot springs was pcrformed by using an approach combining total cellular protein profile identification and 16S rRNA gene sequencing. A total of 328 isolates of bacteria were obtained from liquid and sediment samples from the Xiamen hot springs, including neutrophilie thermophilic bacteria and moderately thermophilic acidophiles. Neutrophilic thermophilic bacteria, which grow at a temperature range of 55-90℃ including Rhodothermus marinus (Strain 1) , Thermus thermophilus (Strain 2), Thermus thiopara (Strain 3) , Geobacillus stearothermophilus(Strain 4) , Geobacillus thermoleovorans (Strain 5) , and Pseudomonas pseudoal-caligenes (Strain 6), were recovered by 2216E plates. Moderately thermophilic acidophiles, which can grow at temperatures above 50℃ and a pH range of 1. 8-3.5 such as Alicyclobacillus acidoterrestris (Strain 8) , Sul-fobacillus acidophilus (Strain 9), and Sulfobacillus thermosulfidooxidans (Strain 10), were isolated on selective solid medium containing sulfur and Fe2+. Among these strains, Rhodothermus marinus, Thermus thermophilus and Geobacillus stearothermophilus are not only thermophilcs, but also halophiles. One bacterium strain (Strain 6) shared 99% nucleotide sequence homology with Pseudomonas pseudoalcaligenes on the 16S rRNA gene se-quence, but was quite different from Pseudomonas pseudoalcaligenes in biological characteristics, suggesting that it may represent a novel thermophilic species. Results indicated that various species of neutrophilic thermophiles and moderately thermophilic acidophiles were widely distributed in the Xiamen hot springs and that Rhodother-mus marinus and Thermus thermophilus dominated the cultivable microbial community. 相似文献
4.
Microbes are believed to play important roles in ecosystem function in many environments. The hot springs of Xiamen Island are close to the Xiamen Sea, and may have some characteristics different from those of inland hot springs. Microbes living in the hot springs of Xiamen may have new characteristics. However, little is known about microbial communities of hot springs close to the Xiamen Sea. A culturedependent survey of microbial population in the Xiamen hot springs was performed by using an approach combining total cellular protein profile identification and 16S rRNA gene sequencing. A total of 328 isolates of bacteria were obtained from liquid and sediment samples from the Xiamen hot springs, including neutrophilic thermophilic bacteria and moderately thermophilic acidophiles. Neutrophilic thermophilic bacteria, which grow at a temperature range of 55—90℃ including Rhodothermus marinus (Strain 1), Thermus thermophilus (Strain 2), Thermus thiopara (Strain 3), Geobacillus stearothermophilus (Strain 4), Geobacillus thermoleovorans (Strain 5), and Pseudomonas pseudoalcaligenes (Strain 6), were recovered by 2216E plates. Moderately thermophilic acidophiles, which can grow at temperatures above 50℃ and a pH range of 1.8—3.5 such as Alicyclobacillus acidoterrestris (Strain 8), Sulfobacillus acidophilus (Strain 9), and Sulfobacillus thermosulfidooxidans (Strain 10), were isolated on selective solid medium containing sulfur and Fe2+. Among these strains, Rhodothermus marinus, Thermus thermophilus and Geobacillus stearothermophilus are not only thermophiles, but also halophiles. One bacterium strain (Strain 6) shared 99% nucleotide sequence homology with Pseudomonas pseudoalcaligenes on the 16S rRNA gene sequence, but was quite different from Pseudomonas pseudoalcaligenes in biological characteristics, suggesting that it may represent a novel thermophilic species. Results indicated that various species of neutrophilic thermophiles and moderately thermophilic acidophiles were widely distributed in the Xiamen hot springs and that Rhodothermus marinus and Thermus thermophilus dominated the cultivable microbial community. 相似文献
5.
A.K. Whitfield 《Estuarine, Coastal and Shelf Science》1984,18(3):315-329
The littoral zone of Swartvlei, an estuarine lake on the southern Cape coast, was characterized by extensive beds of submerged aquatic macrophytes. May 1979 marked the beginning of a regression phase which lasted more than three years. The senescence of the Potamogeton pectinatus and charophyte beds resulted in a 60% decline in primary production, a 74% slump in littoral invertebrate biomass and a 54% decline in the abundance of the fishes Monodactylus falciformis (Lacepede) and Rhabdosargus holubi (Steindachner) associated with the macrophytes. Gravimetric and calorific analyses of their food revealed that invertebrates and filamentous algae from the littoral zone were of major importance. The two fish species consumed approximately 2% of the primary production during the Potamogeton canopy phase and 3% during the Potamogeton senescent phase. Invertebrate consumption declined from 33 mg m?2 day?1 during the canopy phase to 8 mg m?2 day?1 during the senescent phase. The disappearance of the Potamogeton and charophyte beds also resulted in a decrease in the condition of both species but the effect was indirect and related mainly to the collapse of invertebrate stocks associated with the plants. 相似文献
6.
Interaction of 54Mn and 55(59)Fe with EDTA in seawater and NaCl solutions was investigated by high-voltage paper electrophoresis. These two radionuclides were chosen because they represent two modes of behaviour of radionuclides in seawater—EDTA systems. In seawater without EDTA or at low EDTA concentrations in the systems 54Mn behaves as a cation while 55(59)Fe gives a zone at the starting point of the electrophoretic strip. At higher EDTA concentrations, both radionuclides give only one anionic zone showing complexing with EDTA. In the intermediate range of the EDTA concentration (“transition region”) 54Mn shows continuous change of the electrophoretic mobility from cationic to anionic (fast rate of interaction with EDTA), while 55(59)Fe reacts very slowly giving two well-separated zones in the transition region of the EDTA concentration.EDTA concentrations were varied from 10?6 to 10?2M, pH being adjusted to 8.0. The behaviour of radionuclides was followed by measuring the electrophoretic mobilities of radionuclides in dependence on the EDTA concentration at different aging times from 0 to 7 days.From the experimental data effective stability constants and the number of EDTA-ligands of 54MnEDTA and 55(59)FeEDTA complexes in seawater and 0.55 M NaCl solutions were calculated. 相似文献
7.
The isopod Nerocila depressa is present on 54% of the market-sized white sardines (Sardinella albella) caught from an estuary in the Trat province of Thailand. The ventral part of the body, especially the upper pectoral fin, was the area most frequently infected by this parasite. Parasite length was positively correlated with fish length, which suggests that the parasites attach to the fish at a young age. At the site of attachment, the parasites erode the epidermis, dermis and muscular tissue of the Sardinella. Such pathology may cause mortality in many fish. Infestation of this parasite was proportional to the weight of the fish. This study reports a new host for N. depressa attachment and is the first report of S. albella infestation in the Trat province where other known host fish species are cultured. 相似文献
8.
Based on the study of aquatic palynomorph assemblages in two Holocene sediment cores obtained from the eastern Laptev Sea shelf, the main stages in the postglacial transgression are reconstructed for the last 11.3 ky. During that period, the inner shelf of the Laptev Sea (sea depth of 51 m) was already flooded representing an area of intense freshwater sedimentation in the immediate proximity from the river mouth in the period of 11.3 to 10.3 ky B.P. Approximately 1.0–1.5 ky later, the inner shelf (sea depth of 32 m) was flooded, although it remained under the influence of the river runoff up to 7.4 ky B.P. The period of 10.3–7.4 ky B.P. was marked by the dominant dinoflagellate cysts Operculodinium centrocarpum among the aquatic palynomorphs, the appearance of more thermophilic dinoflagellate species, and elevated values of the AH ratio, which indicates an enhanced influx of relatively warm North Atlantic waters to the Laptev Sea shelf. The environment close to the present-day one became dominant on the outer and inner shelf of the Laptev Sea approximately 8.6 and 7.4 ky B.P., respectively. 相似文献
9.
采用MSM寡营养培养基从印度尼西亚Pantai cermin,Kalianda和Banyuwedang三个地区的热泉水样、泥样以及沉积物样品中分离获得细菌菌株,通过检测蛋白酶产生透明圈和福林酚蛋白酶活性测定相结合的方法,从中筛选出1株产嗜热蛋白酶的菌株PBI,该菌株经初步鉴定为短杆菌属(Brevibacillus),并对其酶学性质进行了研究。结果表明,菌株PBI产蛋白酶的最适酶活温度为60℃,最适pH值为8.0～9.0,具有较好的热稳定性和pH稳定性,60℃时酶的半衰期为30min,70℃条件下20min仍保持46.1%的酶活,该酶在pH值为5.0～9.0范围的缓冲液中酶活相对稳定。其产嗜热蛋白酶的酶活力最高可达到60.53U/mL,在100℃条件下仍能保留26.37%的相对酶活。Fe2+,Fe3+,Cu2+和Zn2+对嗜热蛋白酶活性具有明显的抑制作用。该嗜热蛋白酶对EDTA敏感,苯甲基磺酰氟(PMSF)、亮抑酶肽(Leupeptin)、苄眯(Benzamidine)和胃蛋白酶抑制剂(Pepstain A)对该嗜热蛋白酶都有一定的抑制作用,说明其酶活性受到丝氨酸、半胱氨酸残基的影响。结果表明,该菌株是1株具有进一步改造利用价值的产蛋白酶菌株。 相似文献
10.
Nelson A.F. Miranda Renzo Perissinotto Christopher C. Appleton 《Estuarine, Coastal and Shelf Science》2011,91(3):442-449
Gut fluorescence and carbon budget techniques were applied to Tarebia granifera (shell height 10–12 mm) at the iSimangaliso Wetland Park, a UNESCO World Heritage Site. This snail has recently invaded a number of estuaries in northern KwaZulu-Natal, where it reaches densities of over 1000 ind. m?2 and becomes a dominant component of the benthic community. Its rapid establishment and spread have raised concerns about potential top-down impacts on the ecosystem. This study shows that T. granifera can utilize large amounts of microphytobenthos (MPB) in addition to detritus. In situ total available MPB pigment concentrations ranged from 11.6 to 110.5 mg pigm. m?2. T. granifera’s gut pigment content ranged from 54 to 1672 μg pigm. ind?1. Gut evacuation rates (k) ranged from 0.36 to 0.62 h?1 (R2 range: 16.2–35.2, P < 0.05). Individual ingestion rates ranged from 6.6 to 30.4 μg pigm. ind.?1 d?1. T. granifera was estimated to consume from 0.5 to 35% of the total available MPB biomass per day, or 1.2–68% of the daily primary benthic production. The carbon component estimated from the gut fluorescence technique contributed 8.7–40.9% of the total gut organic carbon content. The average carbon daily ration contributed by microalgal biomass was ≈16% body carbon per day. Variability in the data was attributed to the complex feeding history of snails. Further studies are needed to validate these results and provide more information on the ecological impact of T. granifera on this wetland and other similar invaded ecosystems, both estuarine and freshwater. 相似文献
11.
High-saturation (40–100%), microbial gas hydrates have been acquired by expedition GMGS2 from the Taixinan Basin. In this study, geochemical and microbial features of hydrate-containing sediments from the drilling cores (GMGS2-09 and GMGS2-16) were characterized to explore their relationships with gas hydrate formation. Results showed that the average TOC content of GMGS2-09 and GMGS2-16 were 0.45% and 0.63%, respectively. They could meet the threshold for in situ gas hydrate formation, but were not available for the formation of high-saturation gas hydrates. The dominant members of Bacteria at the class taxonomic level were Alphaproteobacteria, Bacilli, Bacteroidia, Epsilonproteobacteria and Gammaproteobacteria, and those in Archaea were Marine_Benthic_Group_B (MBGB), Miscellaneous_Crenarchaeotic_Group (MCG), Group C3, Methanomicrobia and Methanobacteria. Indicators of microbes associated with thermogenic organic matter were measured. These include: (1) most of the dominant microbes had been found dominant in other gas hydrates bearing sediments, mud volcanos as well as oil/coal deposits; (2) hydrogenotrophic methanogens and an oilfield-origin thermophilic, methylotrophic methanogen were found dominant the methanogen community; (3) hydrocarbon-assimilating bacteria and other hyperthermophiles were frequently detected. Therefore, thermogenic signatures were inferred existed in the sediments. This deduction is consistent with the interpretation from the seismic reflection profiles. Owing to the inconsistency between low TOC content and gas hydrates with high saturation, secondary microbial methane generated from the bioconversion of thermogenic organic matters (oil or coal) was speculated to serve as enhanced gas flux for the formation of high-saturation gas hydrates. A preliminary formation model of high-saturation biogenic gas hydrates was proposed, in which diagenesis processes, tectonic movements and microbial activities were all emphasized regarding to their contribution to gas hydrates formation. In short, this research helps explain how microbial act and what kind of organic matter they use in forming biogenic gas hydrates with high saturations. 相似文献
12.
In Palau, Ngerumekaol and Ebiil Channels are spawning aggregation sites that have been protected from fishing since 1976 and 2000, respectively. Groupers and other targeted fisheries species were monitored monthly over a 1.5 year period at these two spawning aggregations and two nearby exploited reference sites where grouper formerly aggregated to spawn. At the protected aggregation sites, three grouper species (Plectropomus areolatus, Epinephelus polyphekadion, and Epinephelus fuscoguttatus) accounted for 78% of the abundance and 85% of the biomass of all resource species surveyed but comprised <1% of the total abundance and biomass at reference sites not protected from fishing that formally harbored spawning aggregations. Abundance and biomass of grouper species pooled were 54% and 72% higher, respectively, at Ngerumekaol compared to Ebiil. Comparisons with data from the same locations in 1995–1996 showed order of magnitude declines in abundance of E. polyphekadion at both locations. The lower numbers of E. fuscoguttatus and the near absence of E. polyphekadion at Ebiil may reflect the effects of previous and current overexploitation. 相似文献
13.
《Deep Sea Research Part I: Oceanographic Research Papers》2005,52(4):569-588
Size-fractionated chlorophyll-a and carbon incorporation rates were determined on a series of 13 cruises carried out from 1992 to 2001with the aim of investigating the patterns and causes of variability in phytoplankton chlorophyll and production in the Eastern North Atlantic Subtropical Gyral Province (NASE). Averaged (±SE) integrated chlorophyll-a concentration and primary production rate were 17±1 mg m−2 and 253±22 mg C m−2 d−1. Small-sized cells (<2 μm) formed the bulk of phytoplankton biomass (71%) and accounted for 54% of total primary production. A clear latitudinal gradient in these variables was not detected. By contrast, large seasonal variability was detected in terms of primary production, although integrated phytoplankton biomass, as estimated from chlorophyll-a concentration, remained rather constant and did not display significant changes with time. Variability in primary production (PP) was related mainly to variability in surface temperature and surface chlorophyll-a concentration. The control exerted by surface temperature was related to nutrient availability. By contrary, euphotic-zone depth, depth of maximum concentration of chlorophyll-a and integrated chlorophyll-a did not contribute significantly to the high variability in primary production observed in this oligotrophic region. 相似文献
14.
15.
从东太平洋热液区E53站位的深海沉积物样品中分离出1株能在65℃生长的嗜热菌（DYth03）.该菌的16S rDNA序列与地芽孢杆菌属（Geobacillus）内各种之间的同源性为98%以上.克隆得到DYth03的DNA聚合酶基因（DYth-pol）,序列分析表明该基因全长为2 631 bp,G＋C含量为55.5%,推测编码为876个氨基酸,与BstDNApolI的同源性最高（达98%）.将该聚合酶基因克隆到pTTQ-h表达载体上,并在大肠杆菌DH1中进行表达.对纯化到的表达产物进行酶活性测定,结果表明该酶具有聚合酶活性和5’-3’外切酶活性. 相似文献
16.
近海温泉中嗜热菌Geobacillus sp. ZH1锰超氧化物歧化酶的克隆与表达 总被引：1，自引：0，他引：1
将嗜热菌Geobacillus sp. ZH1的超氧化物歧化酶(supseroxide dismutase,SOD)基因插入表达载体pET-32α(+),在Escherichia coli BL21(DE3)中进行表达,并利用亲和层析纯化重组超氧化物歧化酶.将制备的脱辅SOD进行Mn2+和Fe2+金属重构后,得到的Mn2+重构SOD的比活力达668U/mg,Fe2+重构Fe-SOD没有活性,说明ZH1菌株的超氧化物歧化酶为Mn-SOD.凝胶过滤及SDS-PAGE分析显示,Mn2+重构SOD为同聚二聚体,亚基分子量为71.7 kDa.这些研究结果为进一步研究该酶的生化特性及酶的定向进化研究奠定了良好的基础. 相似文献
17.
The ECOMAR project was a multidisciplinary process study conducted in the mid-North Atlantic, coincident hydrodynamically with the Sub-Polar Front (SPF; 48–54°N) and topographically with Charlie-Gibbs Fracture Zone of the Mid-Atlantic Ridge, as part of the Census of Marine Life field project MAR-ECO. Midwater trawling was conducted during the 2007 and 2009 ECOMAR expeditions at 14 stations north and south of the SPF, day and night, in four discrete depth intervals from 0 to 1000 m. A total of 56 species of midwater fishes representing 44 genera and 18 families were collected, several of which are new records for the region and/or were not previously sampled during MAR-ECO sampling. An annotated species list with depth-of-capture data is provided. Three species of the genus Cyclothone (Cyclothone braueri, Cyclothone microdon and Cyclothone pallida) and the myctophid Benthosema glaciale combined to contribute ~88% of all specimens collected. This finding differs from results of previous net-based sampling in the same area, likely due to sampling scheme differences (diel sampling, upper 800 m concentration) and gear selectivity (mesh size, trawl speed). Quantitative data from ECOMAR midwater sampling and the previous 2004 G.O. Sars MAR-ECO expedition are compared. Despite differences in gear between the major MAR-ECO expeditions, abundance estimates of some dominant species were remarkably similar. Data showed that the SPF is an asymmetrical, taxon-specific biogeographic boundary for deep-pelagic fishes in the North Atlantic; the SPF is semi-permeable to some species in one direction, while a strong boundary for species in another direction. Deeper-living fish species did not appear as affected by the SPF as a boundary. 相似文献
18.
J.M. Augenfeld J.W. Anderson D.L. Woodruff J.L. Webster 《Marine environmental research》1980,4(2):135-143
Protothaca staminea and Macoma inquinata were exposed to sediment contaminated with 1237 ppm Prudhoe Bay crude oil in the field. Eighty-five per cent of the Protothaca and 17% of the Macoma survived 54 days' exposure. Body burdens of saturated and di- and tri-aromatic hydrocarbons were less than 2 ppm and quite variable. The condition index of Protothaca was reduced by 6% by exposure to oil. The level of free glycine in the mantle, gills and adductor muscle did not change significantly, but the taurine level fell, leading to a decrease in the taurine:glycine ratio. It was concluded that Protothaca, a filter feeder, is affected less severely by oil pollution than Macoma, a detritivore, perhaps because the feeding activity of filter feeders is less inhibited. 相似文献
19.
从迟缓爱德华氏菌（Edwarclsiellatarda）LSE40 fosmid文库克隆到编码寡肽透过酶的opp基因簇。该基因簇全长6741bp，含有5个ORF，依次编码OppA—B-C-D-F5个蛋白；位于oppA翻译起始住点上游385bp处有一个推测的转录起始位点，在该转录起点的-35和-10区分别有TAGACA和TATATT两个特征性启动子序列；位于oppA和oppB的间隔区和oppF之后的非编码区各有一个茎环结构，推测分别为oppA和opp基因簇的转录终止子。氨基酸序列分析表明该基因簇编码的各个蛋白与同属细菌鲶鱼爱德华氏菌（E．ictaluri）对应的各个蛋白高度相似，相似性在96％～98％；与其他革兰氏阴性菌相似性在56％～89％；与革兰氏阳性菌的相似性在27％～53％。以细菌OppA的保守结构域SBP_bac_5构建系统发生树，结果显示E．tardaLSE40与同属细菌E．ictaluri的亲缘关系最近，与肠杆菌科细菌的亲缘关系较近，与革兰氏阳性细菌的亲缘关系较远，表明oppA的SBP_bac_5结构域可作为细菌分类鉴定的依据。opp基因簇的获取为深入了解E．tarda适应环境和宿主的生存机制奠定了基础。 相似文献
20.
We have shown that municipal wastewater and sewage sludge are contaminated by organotins. Here, we investigate the behaviour and fate of tributyltin (TBT) in laboratory-scale sewage sludge treatment at various conditions including both aerobic and anaerobic, and mesophilic and thermophilic. Organotins were determined by capillary GC-FPD. Fresh raw sewage sludge was stored in a tank that was connected to five chemostats maintained at different conditions. Raw sludge contained TBT, dibutyltin (DBT) and monobutyltin (MBT) residues in the range of 0·28 to 0·83 mg/kg (dry weight). The volumetric TBT concentration was 10·5 μg/litre in the influent, and ranged from 7·4 to 8·3 μg/litre in the effluent of the different chemostats. In the anaerobic mesophilic treatment, concentrations of TBT did not decrease with increasing sludge residence time, DBT increased and MBT showed no clear trend. The DBT increase is suggested to be due to leaching from the PVC walls of the chemostats, and not to degradation of TBT alone. The TBT reduction did not show significant differences between the mesophilic and thermophilic anaerobic fermentors. These findings indicate that the degradation of TBT during sludge treatment is only low under all conditions tested. 相似文献