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1.
一株毒死蜱降解菌的分离鉴定及降解性能研究   总被引:4,自引:0,他引:4  
从农药厂废水处理池污泥中分离到一株对毒死蜱有较强降解能力的菌株CH3,通过生理生化试验初步将该菌鉴定为哈夫尼菌属(Hafnia sp.)。CH3能以毒死蜱为唯一碳源生长,在温度为30℃,pH为7.0,毒死蜱初始浓度为200 mg/L的条件下,历时6 d,毒死蜱的降解率可达78.5%。菌株最适生长温度为37℃,最适pH值为7.0,最适降解浓度为200 mg/L。对碳、氮源利用广泛,最佳碳源为蔗糖和葡萄糖,对氮源选择性不高,在无机氮源和有机氮源中均能较好地生长。  相似文献   

2.
微囊藻毒素-LR降解菌的筛选及降解特性研究   总被引:1,自引:0,他引:1  
从上海市淀山湖表层水体中筛选分离出了1株降解微囊藻毒素-LR(MC-LR)的细菌并研究了其降解特性。根据细胞形态结构、生理生化特征及其16S rDNA基因序列分析,鉴定分离菌株DHU-28(GenBank序列登录号为HM047512)属嗜麦芽寡养单胞菌(Stenotrophomonas maltophilia)。微囊藻毒素降解实验结果表明,该菌株能在以MC-LR为唯一碳源、氮源的无机盐培养基中生长,6 d内可将初始质量浓度为15 mg/L的MC-LR降解为8.12 mg/L,降解效率达到45.9%。菌株DHU-28的最适生长温度是30℃,最适生长pH为7.0。酵母粉、蛋白胨、葡萄糖等营养物质可以明显促进菌株对MC-LR的降解效率,尤其是加入50 mg/L酵母粉后,6 d降解率达到63.2%。  相似文献   

3.
从某城市生活污水处理厂曝气池的活性污泥中分离出一株以苯胺为唯一碳源和氮源的高效降解菌Z1。通过16S r DNA基因序列分析,初步鉴定菌株。结果表明,菌株Z1为假单胞菌(Pseudomonas sp.)。该菌株最适生长和降解条件为p H 6.0~8.0、30℃、盐度0.1%~1.0%。在此条件下,16 h内能够将400 mg/L的苯胺降解完全,且当苯胺初始浓度为1 300 mg/L时,苯胺的最大降解速率为41.4 mg/(L·h),32 h内降解率达到98%。菌株对苯胺的最大耐受浓度为1 800mg/L。当苯胺和苯酚共存时,苯胺的降解效果随着苯酚浓度的增大而减小,当苯酚浓度达到370 mg/L时,Z1无法降解苯胺。添加氯化铵做外加氮源能解决高浓度苯酚和苯胺共降解的问题。在苯胺降解过程中大约有43%苯胺态氮转化成氨氮释放到环境中。  相似文献   

4.
低温喹啉降解菌的筛选及降解性能   总被引:2,自引:0,他引:2  
从吉林石化污水处理厂的活性污泥中驯化、筛选获得一株降解效率高且生长速率快高效耐冷菌,命名为WS-5.该菌能以喹啉作为惟一的碳源、氮源及能源.结合菌体的形态观察、生理生化特性实验及16S rDNA序列同源性对比分析,鉴定菌株WS-5为恶臭假单胞菌(Pseudomonas putida).不同降解条件下的实验结果表明,菌株WS-5的最佳降解条件是投菌量为15%,pH值范围在8~10,摇床转速为100 r/min.最佳降解环境下对200 mg/L的喹啉在132 h降解率达到了85.3%.菌株WS-5对初始喹啉浓度为50、100、200和300 mg/L的初始喹啉浓度分别在36、72、192和262 h内完全降解.这将为今后在低温条件下处理含喹啉废水提供技术指导.  相似文献   

5.
从克拉玛依油田附近稠油污染土壤中筛选出能以菲为唯一碳源的菲降解菌y-8,通过形态观察、生理生化特性及16SrDNA比对序列分析对该菌株进行了鉴定,确定菲降解菌y-8属于弯曲假单胞菌(Pseudomonas geniculata)。菲降解菌y-8在30℃、接种量2%(体积分数)、pH=7.0、170r/min的条件下振荡培养72h,对初始质量浓度为100mg/L菲的降解率达到93.7%,同时可耐受较高质量浓度的菲(3 000mg/L)。同时,对不同初始浓度菲降解动力学曲线进行分析,建立菌降解的指数模型,得到一级反应动力学方程:lnc=-0.045 1t+A(其中,c为菲质量浓度,mg/L;t为降解时间,h;A为常数),半减期为91.01h。  相似文献   

6.
采用自制驯化装置,从土壤中分离纯化出一株能以乐果为单一碳源生长的菌株,命名为菌株LPx。根据生理生化特征和16S rRNA(GenBank Accession No.HM488993)基因序列分析,初步将该菌株鉴定为假单胞菌属(Pseudomonas sp.)。通过对其降解乐果特性研究,结果显示,菌株LPx降解乐果的最适pH为7.5、最适温度为30℃、最适接种量为10%(体积分数)。最适条件下,100 mg/L乐果可在120 h内基本被降解。菌株对乐果的降解属于高浓度底物抑制的酶促反应,vmax(不存在抑制剂时最大酶促反应速率)=0.734 d-1,km(米氏常数)=21.700 mg/L,k1(底物抑制系数)=259.215 mg/L。  相似文献   

7.
从长期施用阿特拉津的寒地黑土耕层(0~10cm)土壤中筛选到一株能以除草剂阿特拉津为氮源生长的降解菌株,结合16SrRNA序列分析结果,将该菌株命名为Arthrobacter sp.DNSl0。在接种量为10。CFU/mL的条件下,菌株DNSl0在24h内对100mg/L阿特拉津的降解率为99.41%。单因子实验结果表明,菌株DNSl0适宜生长和降解的条件范围是:温度25~35'12,pH值5.0~8.0,培养液盐度0.1%~2%,对阿特拉津最大耐受浓度可达1200mg/L。正交实验法进一步表明,该菌株保持较好生长及降解能力的最优方案是温度30℃,pH值7.5,培养液盐度0.5%。影响其降解能力的环境因素的主次顺序依次是:温度〉盐度〉pH值。  相似文献   

8.
一株耐盐柴油降解菌的分离鉴定及其降解性能   总被引:2,自引:0,他引:2  
从某油田附近受石油污染土壤中分离出一株以柴油为惟一碳源的耐盐菌株LS1。通过对菌株的生理生化特性、菌体的形态观察及16S r DNA基因序列分析鉴定菌株LS1为假单胞菌属(pseudomonas)。该菌株可耐受的最高盐度(Na Cl)和柴油浓度分别为6%~8%和12 000 mg/L。菌株生长的适宜p H和温度条件分别为6.0~8.0和28~36℃。在盐度为6%、p H为7.0、温度为32℃、菌种投加量为10%的条件下,初始浓度为3 000 mg/L的柴油经6 d降解后,去除率可达78.3%,加入适量外加碳源葡萄糖和蔗糖,可使降解率分别提高至92%和90%左右。菌株LS1的耐盐机理可能是通过在细胞内积累甜菜碱以调节菌株细胞内外渗透压平衡。投加甜菜碱可提高耐盐菌LS1在高盐环境下对柴油的降解效率。  相似文献   

9.
从吉林石化污水处理厂的活性污泥中驯化、筛选获得一株降解效率高且生长速率快高效耐冷菌,命名为WS-5。该菌能以喹啉作为惟一的碳源、氮源及能源。结合菌体的形态观察、生理生化特性实验及16SrDNA序列同源性对比分析,鉴定菌株WS-5为恶臭假单胞菌(Pseudomonasputida)。不同降解条件下的实验结果表明,菌株WS-5的最佳降解条件是投菌量为15%,pH值范围在8~10,摇床转速为100r/min。最佳降解环境下对200mg/L的喹啉在132h降解率达到了85.3%。菌株WS-5对初始喹啉浓度为50、100、200和300mg/L的初始喹啉浓度分别在36、72、192和262h内完全降解。这将为今后在低温条件下处理含喹啉废水提供技术指导。  相似文献   

10.
Trichosporon mycotoxinivorans XPY-10是一株分离自抗生素制药厂的高效四环素降解酵母菌。为了建立该菌株降解四环素的适宜条件,分别研究了碳源、有机氮源、金属离子等营养物质及初始底物浓度、接种量、pH、温度、装液量、摇床转速等理化因素对菌体生长及四环素降解效率的影响。结果表明,菌株XPY-10生长的最适碳源和氮源分别为蔗糖和蛋白胨。在含有0.05%FeSO4的培养基中,菌株XPY—10降解四环素的适宜条件为:接种量2%,pH8,温度3422,装液量100mL(250mL三角瓶),摇床转速180r/min。在此条件下,菌株XPY—10在7d内对初始浓度为600mg/L的四环素降解率为83.63%。本菌株对养殖废水及制药废水中四环素的污染治理有一定的应用前景。  相似文献   

11.
The sorption and desorption of Cu and Cd by two species of brown macroalgae and five species of microalgae were studied. The two brown macroalgae, Laminaria japonica and Sargassum kjellmanianum, were found to have high capacities at pHs between 4.0 and 5.0 while for microalgae, optimum pH lay at 6.7. The presence of other cations in solution was found to reduce the sorption of the target cation, suggesting a competition for sorption sites on organisms. Sorption isotherms obeyed the Freundlich equation, suggesting involvement of a multiplicity of mechanisms and sorption sites. For the microalgae tested, Spirulina platensis had the highest capacity for Cd, followed by Nannochloropsis oculata, Phaeodactylum tricornutum, Platymonas cordifolia and Chaetoceros minutissimus. The reversibility of metal sorption by macroalgae was examined and the results show that both HCl and EDTA solutions were very effective in desorbing sorbed metal ions from macroalgae, with up to 99.5% of metals being recovered. The regenerated biomass showed undiminished sorption performance for the two metals studied, suggesting the potential of such material for use in water and wastewater treatment.  相似文献   

12.

The bioavailability of pollutants, pesticides and/or their degradation products in soil depends on the strength of their sorption by the different soil components, particularly by the clay minerals. This study reports the sorption-desorption behavior of the environmentally hazardous industrial pollutants and certain pesticides degradation products, 3-chloroaniline, 3,4-dichloroaniline, 2,4,6-trichloroaniline, 4-chlorophenol, 2,4-dichlorophenol and 2,4,6-trichlorophenol on the reference clays kaolinite KGa-1 and Na-montmorillonite SWy-l. In batch studies, 2.0 g of clay were equilibrated with 100.0 mL solutions of each chemical at concentrations ranging from 10.0 to 200.0 mg/L. The uptake of the compounds was deduced from the results of HPLC-UV-Vis analysis. The lipophilic species were best retained by both clay materials. The most lipophilic chemical used in the study, 2,4,6-trichloroaniline, was also the most strongly retained, with sorption of up to 8 mg/g. In desorption experiments, which also relied on HPLC-UV-Vis technique, 2,4,6-trichloroaniline was the least desorbed from montmorillonite. However, on kaolinite all of the compounds under study were irreversibly retained. The experimental data have been modelled according to the Langmuir and Freundlich isotherms. A hypothesis is proposed concerning the sorption mechanism and potential applications of the findings in remediation strategies have been suggested.  相似文献   

13.
The bioavailability of pollutants, pesticides and/or their degradation products in soil depends on the strength of their sorption by the different soil components, particularly by the clay minerals. This study reports the sorption-desorption behavior of the environmentally hazardous industrial pollutants and certain pesticides degradation products, 3-chloroaniline, 3,4-dichloroaniline, 2,4,6-trichloroaniline, 4-chlorophenol, 2,4-dichlorophenol and 2,4,6-trichlorophenol on the reference clays kaolinite KGa-1 and Na-montmorillonite SWy-l. In batch studies, 2.0 g of clay were equilibrated with 100.0 mL solutions of each chemical at concentrations ranging from 10.0 to 200.0 mg/L. The uptake of the compounds was deduced from the results of HPLC-UV-Vis analysis. The lipophilic species were best retained by both clay materials. The most lipophilic chemical used in the study, 2,4,6-trichloroaniline, was also the most strongly retained, with sorption of up to 8 mg/g. In desorption experiments, which also relied on HPLC-UV-Vis technique, 2,4,6-trichloroaniline was the least desorbed from montmorillonite. However, on kaolinite all of the compounds under study were irreversibly retained. The experimental data have been modelled according to the Langmuir and Freundlich isotherms. A hypothesis is proposed concerning the sorption mechanism and potential applications of the findings in remediation strategies have been suggested.  相似文献   

14.
The persistence and dissipation kinetics of trifloxystrobin and tebuconazole on onion were studied after application of their combination formulation at a standard and double dose of 75 + 150 and 150 + 300 g a.i. ha?1. The fungicides were extracted with acetone, cleaned-up using activated charcoal (trifloxystrobin) and neutral alumina (tebuconazole). Analysis was carried out by gas chromatograph (GC) and confirmed by gas chromatograph mass spectrometry (GC-MS). The recovery was above 80% and limit of quantification (LOQ) 0.05 mg kg?1 for both fungicides. Initial residue deposits of trifloxystrobin were 0.68 and 1.01 mg kg?1 and tebuconazole 0.673 and 1.95 mg kg?1 from standard and double dose treatments, respectively. Dissipation of the fungicides followed first-order kinetics and the half life of degradation was 6–6.6 days. Matured onion bulb (and field soil) harvested after 30 days was free from fungicide residues. These findings suggest recommended safe pre-harvest interval (PHI) of 14 and 25 days for spring onion consumption after treatment of Nativo 75 WG at the standard and double doses, respectively. Matured onion bulbs at harvest were free from fungicide residues.  相似文献   

15.
The kinetic and structural relationships of eight electrophoretically pure mammalian serum and liver serine carboxylesterases (CE) and cholinesterases (ChE) have been studied. Eight CE's and ChE's, which were fully resolved but only partially purified, provided additional information. Five of the electrophoretically pure esterases were monomeric, and of these, four belonged to a new and widely distributed class. These four monomeric esterases hydrolyzed choline esters, but at widely differing rates. Thus two were termed monomeric butyrylcholinesterases, mBuChE I and II, and two were monomeric CE's (mCE). The rabbit liver mCE was not a subunit of the oligomeric CE (oCE), although the oCE also hydrolyzed choline esters at a very low rate. The complex kinetics of the mCE's, mBuChE's, oCE's, and of the oligomeric BuChE's of horse and human serum could be interpreted according to a single reaction scheme involving an allosteric site and the equation derived from it. Thus activation and inhibition at high substrate concentrations, together with sigmoidal activity versus substrate concentration plots, all of which characterize the reactions of these esterases, could be interpreted by a single scheme and equation. Structural and kinetic comparisons showed a progressive transition of properties from the oCE's through the mCE's to the oBuChE's. One of the purified mCE's was from horse serum, and it exhibited physical and kinetic properties unlike those of the liver mCE's or oCE's.  相似文献   

16.
PCDD and PCDF were found in urban air particulates from St. Louis and Washington, D.C., and in sediments from the Great Lakes and Siskiwit Lake, Isle Royale. The similarity between the PCDD and PCDF found in air particulates and sediment samples and the presence of PCDD and PCDF in sediment from Siskiwit Lake (a location which can receive only atmospheric inputs) suggest that these compounds are emitted to the atmosphere from combustion sources. The historical input of PCDD and PCDF to dated sediment cores shows a strong increase since 1940, and this suggests that the incineration of chlorinated organic compounds is an important source of PCDD and PCDF to the environment.  相似文献   

17.
18.
畜禽养殖业污染与循环经济   总被引:16,自引:0,他引:16  
解决畜禽养殖业的污染问题要以充分利用资源为根本出发点,通过对污染全过程控制及废物综合利用,达到畜禽粪便的减量化、无害化、资源化,走循环经济的发展道路。  相似文献   

19.
Chemical synthesis and physical properties of two mercapturic acids suggested as urinary metabolites of m- and p-xylenes ace described. These compounds may be used for the identification and quantivative determination by high-performance liquid chromatography of the corresponding mercapturic acids in urine.  相似文献   

20.
Environmental Science and Pollution Research - Hydrocarbon is a primary source of energy in the current urbanized society. Considering the increasing demand, worldwide oil productions are declining...  相似文献   

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