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1.
通过富集培养及平板升华法从本溪钢铁公司周边多环芳烃(PAHs)污染土壤中分离出7株PAHs降解菌。以芘和苯并[a]芘为底物进行摇瓶降解实验,结果表明:G1、G2和G3菌株对高环PAHs芘和苯并[a]芘均具有较强的降解能力。进一步研究此3株菌及混合菌对原状污染土壤中PAHs的降解能力,发现80 d时对总PAHs的降解顺序依次为:混合菌G2G1G3,其中混合菌对PAHs降解率较单菌分别提高了9.17%、11.49%和16.11%;4个处理对4~6环PAHs的降解率较对照组相比提高的倍数随着环数增加而增大;总PAHs的降解率与脱氢酶的活性呈正相关。电场影响G1、G2和G3菌株对PAHs降解,在1.0 V·cm~(-1)电场条件下,4环、5环及6环PAHs降解率较单纯微生物修复提高12.13%、13.35%和14.52%,说明3株菌具有较强的电场适应能力,可在高环PAHs污染土壤的电动-微生物修复中应用。形态学观察及16S rRNA序列比对分析表明,G1、G2、G3菌株分别为鞘氨醇单胞菌属(Sphingomonas sp.)、苍白杆菌属(Ochrobactrum sp.)和无色杆菌属(Achromobacter sp.)。  相似文献   

2.
从辽河流域浑河沈阳段采集底泥样品,利用吸附性载体,以芘为唯一碳源,筛选到一株芘高效降解菌F8,根据形态。生理生化特性及测序结果鉴定该菌为产碱杆菌(Alcaligenes sp.)。对菌株F8降解率进行测定,结果表明,菌株F8在32℃振荡培养条件下,7d后对50 mg·L~(-1)的芘降解率为62.75%,芘的降解与细菌浓度的增长呈正相关关系?通过对其培养条件优化,确定其生长的最适温度和pH分别为36℃和6.5。对菌株F8在重金属离子胁迫下的生长研究发现,Cd~(2+)对菌株F8有毒性;Zn~(2+)对菌株有一定的抑制作用;Cu~(2+)对菌株生长影响很小。研究了植物-微生物联合修复作用,结果显示水稻促进了菌株F8对芘的降解,使降解率增加了11.85%。  相似文献   

3.
为丰富多环芳烃降解菌菌种库、降低农作物的污染风险,本研究对一株可高效降解多环芳烃(PAHs)的植物内生菌进行筛选鉴定,并初步探究其降解途径以及定殖效能。结果表明: 菌株PX1为嗜麦芽寡养单胞菌。该菌株对多环芳烃的降解具有广谱性,7 d几乎可彻底降解PAH无机盐培养基中的萘,在分别含有50.0 mg·L-1菲、20.0 mg·L-1芘、20.0 mg·L-1荧蒽和10.0 mg·L-1苯并[a]芘的培养体系中,对菲、芘、荧蒽、苯并[a]芘的降解率分别为72.6%、50.7%、31.9%和12.9%。选取芘作为PAHs模型研究菌株PX1的降解特性。酶活性试验表明,芘可诱导菌株PX1体内邻苯二甲酸双加氧酶、邻苯二酚-1,2-双加氧酶和邻苯二酚-2,3-双加氧酶的活性。在芘降解过程中检测到4,5-环氧化芘、4,5-二羟基芘、龙胆酸/原茶儿酸、水杨酸、顺-己二烯二酸/2-羟粘糠酸半醛、顺-2′-羧基苯丙酮酸、1-羟基-2-萘甲酸、水杨醛等中间产物。浸种定殖试验表明,菌株PX1可高效定殖到空心菜和小麦体内,显著促进空心菜和小麦生长,并能够将空心菜、小麦体内及其生长基质中的芘浓度分别降低29.8%~50.7%、52.4%~67.1%和8.0%~15.3%。表明菌株PX1主要通过“水杨酸途径”和“邻苯二甲酸途径”降解芘,且可以定殖到植物体内,促进植物生长。  相似文献   

4.
采用富集培养方法从多环芳烃污染土壤中筛选分离得到1株能以苯并[a]芘(B[a]P)为唯一碳源和能源生长的菌株.形态特征观察和16S rDNA序列分析结果表明,该菌株为副球菌属(Paracoccus sp.),编号为HPD-2.HPD-2在3.0 mg/L的B[a]P液体培养基中生长较慢,培养5 d后B[a]P的降解率为89.7%.同时,该菌株对四环的芘和荧蒽也具有较好的降解能力,培养7 d后芘和荧蒽的降解率分别达到47.2%和84.5%.可见,该菌株对高分子量PAHs具有很好的降解潜力.  相似文献   

5.
采用富集培养和多环芳烃双加氧酶基因检测方法,从焦化场地多环芳烃污染土壤分离筛选出9株PAHs降解菌。以高分子量多环芳烃芘为唯一碳源进行摇瓶降解实验,结果表明,J6、S5、S4、S2和B4对芘具有较好的降解能力,21 d时芘降解率均达55%以上,其中B4处理芘的降解率最高,达到70.2%。进一步研究了该5株菌及其混合菌对土壤中芘的降解效果,发现混合菌的降解效果高于单菌的降解效果,其中混合菌H4和单菌B4的降解效果较好,49 d时混合菌H4和单菌B4处理土壤中芘的降解率达29.3%和18.3%。经过16S rRNA基因序列比对,鉴定J6菌株为赤红球菌(Rhodococcus ruber),S5为芽孢杆菌属(Bacillus sp.),S4和S2是鞘脂单胞菌属(Sphingopyxis sp.),B4为假单胞菌属(Pseudomonas sp.)。在电场条件下,混合菌H4和单菌B4处理微生物数量及活性均显著提高,芘的降解率较单独H4和B4处理提高33.0%和20.1%,说明筛选出的5株高分子量多环芳烃降解菌具有较强的电场适应能力,可在高分子量多环芳烃污染土壤电动-微生物修复中应用。  相似文献   

6.
高效芘降解菌N12的分离鉴定与降解特性   总被引:2,自引:0,他引:2  
以芘为目标降解物,利用选择性富集培养方法,从沈抚灌区污染土壤中分离到一株高效芘降解菌N12,经生理生化试验和16S rDNA测序分析,该菌被鉴定为分枝杆菌属(Mycobacterium sp.).菌株N12能以菲、苊、芴和芘为唯一碳源和能源生长,不能以蒽、萘和苯并芘为唯一碳源和能源生长.在菲和芘共同存在的情况下菌株N12可降解苯并芘,9 d内对苯并芘降解率可达79.0%.摇瓶降解试验表明,菌株N12可在7 d内将100 mg·L-1的芘降解94.4%,14 d内将其完全降解;可将600 mg·L-1的芘在7 d内降解56.1%,14 d内降解95.5%.添加葡萄糖可促进N12对芘的降解.菌株N12是一株优良的多环芳烃降解菌,可作为多环芳烃污染土壤生物修复的菌种资源.  相似文献   

7.
多环芳烃降解菌的筛选与降解能力测定   总被引:3,自引:0,他引:3  
从本溪多环芳烃(PAHs)污染土壤中经富集培养筛选出8株PAHs降解菌,研究了8株菌及其等比例混合培养对菲、芘和苯并[a]芘的降解能力。结果表明,在28℃,培养基中菲、芘和苯并[a]芘的浓度分别为50、50和5mg·L-1的复合底物条件下,培养28d后,菌株B3的降解效果最好,对菲、芘和苯并[a]芘的降解率分别为88.4%、54.0%和68.4%,8株菌的混合培养对菲、芘和苯并[a]芘的降解率分别为87.7%、35.3%和42.0%;经生理生化实验和16SrRNA序列比对,初步鉴定B3菌为假单胞菌属(Pseudomonas sp.)。  相似文献   

8.
焦化厂地肤根内解芘细菌的筛选及促生潜力   总被引:1,自引:0,他引:1  
从多环芳烃耐受植物根内分离具多环芳烃降解功能的内生细菌并研究其促生特性,为内生菌协同宿主植物修复多环芳烃污染土壤提供基础.以长期受多环芳烃污染的焦化厂区生长的地肤为材料,从其根内分离出以芘和1-氨基环丙烷-1-羧酸(ACC)为唯一碳源和氮源的内生细菌8株.通过芘降解试验,筛选得到3株高效芘降解内生细菌KSE4、KSE7和KSE8,经鉴定分别为芽孢杆菌属、假单胞菌属和鞘氨醇菌属.通过液体培养试验,研究了3株菌在芘胁迫下产ACC脱氨酶的能力和对地肤种子萌发的影响.结果表明: 随着芘浓度(0~15 mg·L-1)的升高,ACC脱氨酶活性降低,其中KSE7的效果最好,在芘浓度为15 mg·L-1时,地肤发芽率和芽长分别比对照提高了44.8%和61.1%,在地肤-微生物修复焦化厂污染土壤的修复中具有一定的应用潜力.  相似文献   

9.
为丰富机油降解微生物菌种库,筛选适应性更强的机油高效降解菌株。以20#机油和真空泵油为唯一碳源,筛选出机油高效降解菌,经细菌形态学、生理生化及16S rRNA序列分析对机油高效降解菌株进行鉴定,采用紫外分光光度法和气相色谱质谱联用(GC-MS)研究菌株降解特性。从初筛的22株机油降解菌中筛选出4株机油高效降解菌株,分别为JZ6、JZ18、JZ41和JZ50,经鉴定4株菌株分别为Massilia sp、Pseudomona sp、Sphingobacterium sp和Shinella zoogloeoides sp,在含机油培养基中30℃培养7 d后,机油降解率分别为42.62%、33.67%、33.36%和40.52%。在温度20-40℃,pH5-9条件下菌株都具有降解机油的能力,4株菌株均能以十二烷、十六烷、十八烷和苯和萘为唯一碳源生长,JZ6和JZ50还能在含芘和菲的培养基中生长。GC-MS分析发现菌株JZ6、JZ18、JZ41和JZ50对总烷烃的降解率分别达到68.66%、52.69%、49.37%和61.40%,对直链烷烃的降解率分别为86.89%、55.98%、58.42%和89.13%,其中菌株JZ6和JZ50对除烷烃的其他芳香烃类物质也具有一定的降解作用。筛选出的4株机油降解菌具有较强机油降解能力,适应性强,可用于机油污染环境的生物修复。  相似文献   

10.
盐碱土壤PAHs 降解菌的筛选鉴定及其降解特性   总被引:4,自引:2,他引:2  
采用富集培养的方法,从天津大港油田PAHs污染盐碱化土壤中分离出一株能以菲、芘为唯一碳源和能源的优势菌TJB5。经形态观察和16S rDNA序列分析结果表明,该菌株为成团泛菌(Pantoea agglomerans)。采用液体培养的方法,研究了pH、盐度、菲芘的初始浓度对TJB5菌株降解菲芘效果的影响,确定了最佳降解条件。结果表明,该菌对菲、芘的降解具有较广泛的pH、盐度范围和良好的降解效果。在菲、芘浓度分别为50 mg/L、pH 6.8-9.5、盐度2%-3%、温度30°C条件下,接种15 d后菲降解率在93.3%以上,芘降解率在20%以上。  相似文献   

11.
The goal of this article was to establish reference ranges of the concentration of trace elements in human serum and to compare these results with those reported by other authors. We describe the sample preparation and measurement conditions that allow the rapid, precise, and accurate determination of Al, As, B, Be, Cd, Co, Cu, Fe, Li, Mn, Mo, Ni, Rb, Se, Sr, and Zn in human serum samples (n=110) by inductively coupled plasma-mass spectrometry (ICP-MS). Accuracy and precision were determined by analyzing three reconstituted reference serum samples by comparison with other methods and by the standard addition procedure. The advantages of the ICP-MS method include short time of analysis of the elements mentioned, low detection limit, high precision, and high accuracy. Disadventages include a high risk of contamination due to the presence of some of the elements of interest in the environment, the relatively delicate sample handling, and the high cost of the equipment.  相似文献   

12.
Summary Concentration of N, P, K, Ca, Mg and S in summer groundnut crop was higher than in kharif while Zn, Fe, Mn and Cu contents were higher in summer crop. Kernel's N, P and Zn; Leaflet's Ca and Mn; Stem's K and Fe; Root's S and Cu and Petiole's Mg contents were highest. Shell's N, P, K, Mg, S, Zn and Cu; Kernel's Ca, Fe and Mn contents were the least. N, P, K, S, Zn and Cu concentrations decreased linearly as the crop grew. Ca, Mg, Fe and Mn concentrations did not display any distinct pattern. Ca concentration was positively correlated with pod yield in both the seasons.  相似文献   

13.
A new polynitro cage compound 2, 4, 6, 8, 10, 12, 13, 14, 15-nonanitro-2, 4, 6, 8, 10, 12, 13, 14, 15-nonaazaheptcyclo [5.5.1.1(3,11).1(5,9)] pentadecane (NNNAHP) was designed in the present work. Its molecular structure was optimized at the B3LYP/6-31 G(d,p) level of density functional theory (DFT) and crystal structure was predicted using the Compass and Dreiding force fields and refined by DFT GGA-RPBE method. The obtained crystal structure of NNNAHP belongs to the P-1 space group and the lattice parameters are a = 9.99 ?, b = 10.78 ?, c = 9.99 ?, α = 90.01°, β = 120.01°, γ = 90.00°, and Z = 2, respectively. Based on the optimized crystal structure, the band gap, density of state, thermodynamic properties, infrared spectrum, strain energy, detonation characteristics, and thermal stability were predicted. Calculation results show that NNNAHP has detonation properties close to those of CL-20 and is a high energy density compound with moderate stability.  相似文献   

14.
This report attempts to formulate reference ranges of elemental concentrations for 15 trace elements in selected human tissues and body fluids. A set of samples consisting of whole blood, blood serum, urine, milk, liver, and hair were chosen and considered for 15 elements of biological significance: As, Cd, Co, Cr, Cu, F, Fe, I, Hg, Mn, Mo, Ni, Pb, Se, and Zn. The results represent wholly or partially data received from 40 countries of the global regions of Africa, Asia, Europe, North, South, and Central America, Australia, and New Zealand. This survey, even if qualitative, has been useful in demonstrating certain trends of trace-element scenarios around the world. It is of course recognized that both diet and environment exert a strong influence on the distribution pattern of several elements, such as As, Cd, Mn, Pb, Se, and Zn. A limited comparison of the available information on soil status of different countries reflected some interesting associations for elements, such as Mn and Zn. Importantly, this study revealed that only a few countries were in a position to identify a reasonable amount of data on samples requested for this project. Regretably, for a number of countries, any dependable data for even such essential elements as Cu, Fe, and Zn were not available. In view of the nutritional importance of many elements, the time is ripe for concerted efforts by intergovernmental agencies to initiate investigations or commission task forces/projects to generate reliable reference data for selected global regions, which sadly lack data of any kind at present.  相似文献   

15.
16.
The variation with age of the 18 trace element mass fractions and some histological characteristics of intact prostate glands of 50 subjects aged 0–30 years was investigated by instrumental neutron activation analysis, inductively coupled plasma atomic emission spectrometry, and a quantitative morphometric analysis. Mean values ± standard error of the mean (M ± SΕΜ) for the mass fractions (in milligrams per kilogram wet tissue) of these trace elements in pre-puberty were: Al 28.5 ± 9.0, B 0.40 ± 0.11, Ba 1.48 ± 0.44, Br 10.5 ± 1.5, Ca 241 ± 30, Cl 3,203 ± 278, Cu 3.51 ± 0.89, Fe 33.7 ± 4.1, K 2,364 ± 145, Li 0.020 ± 0.004, Mg 153 ± 23, Mn 0.46 ± 0.06, Na 2,286 ± 130, P 1,391 ± 100, S 1,698 ± 132, Si 62 ± 11, Sr 0.38 ± 0.08, and Zn 27.6 ± 2.3. During puberty and postpuberty, when there is a significant increase in circulating androgens, the mean values were: Al 7.2 ± 1.4, B 0.21 ± 0.05, Ba 0.25 ± 0.06, Br 5.8 ± 1.0, Ca 433 ± 81, Cl 2,314 ± 201, Cu 1.77 ± 0.13, Fe 20.9 ± 1.6, K 2,585 ± 118, Li 0.0088 ± 0.0014, Mg 232 ± 27, Mn 0.34 ± 0.04, Na 1,875 ± 107, P 1,403 ± 98, S 1,673 ± 73, Si 22.2 ± 3.1, Sr 0.22 ± 0.03, and Zn 93.3 ± 8.9. Mean values (M ± SΕΜ) of percent volumes (%) of the stroma, epithelium and lumen in the prostate before puberty were 73.4 ± 2.6, 20.4 ± 1.7, and 4.45 ± 0.94, respectively, versus 46.5 ± 2.5, 38.5 ± 1.9, and 14.9 ± 1.2 during puberty and postpuberty. This work’s results confirm that the Zn mass fraction in prostate tissue is an androgen-dependent parameter. For the first time it has been demonstrated that the glandular lumen is a main pool of Ca, Mg, and Zn accumulation and that the stroma is a main pool of Al, B, Ba, Br, Cl, Cu, Fe, Mn, Na, and Si accumulation in the normal human prostate, for the age range 0–30 years. It was concluded that the Ca, Mg, and Zn binds tightly within the prostatic fluid, because the volume of glandular lumen reflects the volume of prostatic fluid.  相似文献   

17.
The effect of age and gender on major, minor, and trace element contents in the intact rib bone of 80 relatively healthy 15–55-year-old women and men was investigated. Contents or upper limit of contents of 16 chemical elements in the rib bone were determined by inductively coupled plasma atomic emission spectrometry (ICP-AES). Mean values (M?±?SΕΜ) for the mass fraction of Ba, Ca, Cu, Fe, K, Li, Mg, Na, P, S, Sr, and Zn (milligram per kilogram of dry bone) were as follows: 2.54?±?0.16, 171,400?±?4,050, 1.35?±?0.22, 140?±?11, 1,874?±?71, 0.049?±?0.011, 2,139?±?38, 5,378?±?88, 75,140?±?1,660, 1,881?±?51, 291?±?20, and 92.8?±?1.5, respectively. The upper limits of contents of Al, B, Mn, and V were <7.20, <0.65, <0.36, and <0.03, respectively. Statistically significant tendency for the Ca, Mg, and P content to decrease with age was found in the human rib bone, regardless of gender. The mass fraction of Fe in the male rib bone increases with age. It was shown that higher Ca, Mg, Na, P, and Sr mass fractions as well as lower Fe content were typical of female ribs as compared to those in male ribs.  相似文献   

18.
The unitary conductances and permeability sequences of the rat connexin40 (rCx40) gap junction channels to seven monovalent cations and anions were studied in rCx40-transfected neuroblastoma 2A (N2A) cell pairs using the dual whole cell recording technique. Chloride salt cation substitutions (115 mM principal salt) resulted in the following junctional maximal single channel current-voltage relationship slope conductances (γj in pS): CsCl (153), RbCl (148), KCl (142), NaCl (115), LiCl (86), TMACl (71), TEACl (63). Reversible block of the rCx40 channel was observed with TBA. Potassium anion salt γj are: Kglutamate (160), Kacetate (160), Kaspartate (158), KNO3 (157), KF (148), KCl (142), and KBr (132). Ion selectivity was verified by measuring reversal potentials for current in rCx40 gap junction channels with asymmetric salt solutions in the two electrodes and using the Goldman-Hodgkin-Katz equation to calculate relative permeabilities. The permeabilities relative to Li+ are: Cs+ (1.38), Rb+ (1.32), K+ (1.31), Na+ (1.16), TMA+ (0.53), TEA+ (0.45), TBA+ (0.03), Cl (0.19), glutamate (0.04), and NO3− (0.14), assuming that the monovalent anions permeate the channel by forming ion pairs with permeant monovalent cations within the pore thereby causing proportionate decreases in the channel conductance. This hypothesis can account for why the predicted increasing conductances with increasing ion mobilities in an essentially aqueous channel were not observed for anions in the rCx40 channel. The rCx40 effective channel radius is estimated to be 6.6 Å from a theoretical fit of the relationship of relative permeability and cation radius.  相似文献   

19.
Nine blood group systems of goats were identified using 12 caprine reagents produced by absorption of alloimmune antisera. The caprine C blood group system, possibly homologous to the ovine C blood group system, was characterized by two reagents and shown to be controlled by three alleles,C 12,C 25, andC . A more complex blood group system of goats, designated G, was identified using three reagents and shown to be controlled by six codominant alleles (G 10.19.20,G 10.19,G 10.20,G 10,G 19,G 20) and a recessive allele (G ). A further seven one-factor two-allelic systems were identified by seven reagents. The nine genetic systems provided exclusion probabilities of 0.479, 0.492, 0.548, and 0.572 in Australian Angora, Dairy, Cashmere, and Texan Angora goat breeds, respectively. This work was supported by a grant from the Australian Stud Book, Alison Road, Randwick, New South Wales 2031, Australia.  相似文献   

20.
《Ibis》1894,36(3):447-460
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