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1.
为建立产氢不产氧光合菌株的快速筛选方法,从采自陕西、河南、安徽3个省8份不同水样中分离出的不产氧光合细菌,通过菌落形态、革兰氏染色、细菌特征峰及16SrDNA鉴定等方法进行初步鉴定获得不产氧光合细菌,同时利用自制的产氢菌株快速筛选系统对其产氢能力进行检测,并分析菌液终点氧化还原电位与细胞产氢的关系。结果表明:共分离得到31株光合细菌,其中18株沼泽红假单胞菌(Rhodopseudomonas palustris)、5株荚膜红细菌(Rhodobacter capsulatus)、4株球形红细菌(Rhodobacter sphaeroides)和2株固氮红细菌(Rhodobacter azotoformans),此外还有2株菌与Rhodobacter sp.TCRI 14相似。这些光合细菌的产氢能力存在显著差异,其中3株产氢性能较高,2株为沼泽红假单胞菌,1株为球形红细菌。通过菌液终点氧化还原电位与细胞产氢能力对比,发现产氢较高的菌株其菌液的终点氧化还原电位也明显较低。  相似文献   

2.
本文应用微生物学和生物化学方法,对酸菜复合发酵剂中的菌株进行了分离、纯化,并对其生化特性进行了研究.结果显示:该复合式发酵剂中不含酵母菌,均为乳酸菌.其中分离得到乳酸单球菌两株,乳酸杆菌两株,链球菌一株,双球菌一株.这6株菌的过氧化氢酶试验、硫化氢试验、吲哚试验、硝酸盐还原试验、尿素试验、甲基红试验和维培试验结果均为阴性,均不可利用葡萄糖产气,属同型乳酸发酵.6株试验菌株在15 ~45℃下生长旺盛,属中温菌,适合用于工业生产使用.试验菌株均可利用二糖(蔗糖、乳糖、麦芽糖),均不利用多糖(淀粉、木糖).各菌株的产酸量都在0.4%以上.  相似文献   

3.
Some Rhizobium strains synthesize a unidirectional hydrogenase system in legume nodule bacteroids; this system participates in the recycling of hydrogen that otherwise would be lost as a by-product of the nitrogen fixation process. Soybeans inoculated with Rhizobium japonicum strains that synthesized the hydrogenase system fixed significantly more nitrogen and produced greater yields than plants inoculated with strains lacking hydrogen-uptake capacity. Rhizobium strains used as inocula for legumes should have the capability to synthesize the hydrogenase system as one of their desirable characteristics.  相似文献   

4.
板栗6个不同品种的果实对炭疽病的抗性差异显著,对与抗性有关的过氧化氢酶、过氧化物酶、过氧化物酶同工酶及SOD同工酶的分析表明:过氧化氢酶及过氧化物酶活性与板栗果实抗病性密切相关;过氧化氢酶活性越低,过氧化物酶活性越高,果实的抗性越强;过氧化物酶同工酶及SOD同工酶谱在一定程度上表明了品种间果实的抗性差异。  相似文献   

5.
李亚丽 《安徽农业科学》2011,39(31):19039-19041
[目的]为光合细菌制氢的工业化发展奠定基础。[方法]以光合细菌混合菌群为试验菌种,研究其在连续制氢反应器中的浓度变化、产氢特性及细菌数量与产氢量的关系。[结果]连续制氢反应器的2#、3#隔室光合细菌浓度最大,产氢量也最大。同一隔室内,第2、3 d光合细菌浓度和产氢量均达到最大。[结论]产氢量随反应器中光合细菌数量的减少而减少。  相似文献   

6.
[目的]研究3株药用乳酸杆菌的生理生化特征。[方法]观察3株乳杆菌L2、L3、L8在不同培养基上的生长形态及生长状况,并对其进行革兰氏染色、甲基红和V-P试验及乳酸和过氧化氢鉴定,最后观察它们对不同糖类的利用情况。[结果]菌株L2、L3、L8均为革兰氏阳性菌,且与GAM培养基相比,其在MRS培养基上的生长状况更为良好;L2、L3、L8的甲基红试验均为阳性,V-P试验均为阴性,且都产过氧化氢、乳酸,但3株菌之间的乳酸产量无明显差别;L2、L3、L8对不同糖类的利用情况基本相似。[结论]该研究为3株乳杆菌L2、L3、L8的进一步药用化奠定了基础。  相似文献   

7.
不同酸泡菜中产细菌素植物乳杆菌的筛选   总被引:1,自引:0,他引:1  
从6种泡菜中分离出217株乳杆菌,通过琼脂点扩散交叉拮抗试验,筛选出发酵液有抑菌作用的12株植物乳杆菌。排除了酸、过氧化氢的作用后,7株的离心发酵液对来自于甘蓝泡菜的1株植物乳杆菌Lactobacillus plantarum 96D 仍有抑菌活性,用胰蛋白酶对其处理后抑菌活性丧失,说明它们产生的抑菌物质是细菌素。其中 G_6,G_8,G_9和 H_(16)菌株抑菌效果较显著。  相似文献   

8.
发酵床除臭微生物的筛选与Z-22菌株的鉴定   总被引:1,自引:0,他引:1  
从猪场采集土样,经过初筛、芽孢鉴定、感官法等步骤,筛选出9株有一定除臭能力的产芽孢菌株,对筛选出的9株菌进行分解利用NH3和H2S能力的检测,最终得到1株有较强除臭能力的芽孢杆菌Z-22.依据形态特征、生理生化试验和16S rDNA全序列分析,鉴定Z-22菌株为解淀粉芽孢杆菌(Bacillus amylolique aciens).该菌株对NH3的去除率为29.2%,对H2S的去除率为52%,具有明显的除臭效果,为微生态发酵床的研究提供了微生物种质资源.  相似文献   

9.
健康犬肠道乳酸杆菌某些生物学特性的研究   总被引:5,自引:0,他引:5  
从健康犬的肠道中分离并鉴定出5株乳酸杆菌,其中嗜酸乳杆菌3株、肠乳杆菌1株、发酵乳杆菌1株。根据其耐胆盐、生长表现等特性选择2株嗜酸乳杆菌(D1-3、D4-3),作进一步的耐酸性、粘附性、抑菌作用等生物学特性试验。结果表明:D1-3和D4-3菌株能耐受高达6.0g/L的胆盐以及pH值低至2.0的酸性环境,对犬肠粘膜上皮细胞有良好的粘附性,其代谢产物对常见致病菌有较好的抑制作用,对小白鼠无毒性。  相似文献   

10.
为了治理恶臭对环境的污染,利用初筛与复筛相结合的方法,获得了对氨去除率达80%以上、对硫化氢去除率达60%以上的菌株。对有效菌株进行垃圾除臭试验,采用对比试验检验除臭效果。结果表明:除臭菌株在24h内可有效减少垃圾产生的恶臭。  相似文献   

11.
Olson JW  Maier RJ 《Science (New York, N.Y.)》2002,298(5599):1788-1790
The gastric pathogen Helicobacter pylori is known to be able to use molecular hydrogen as a respiratory substrate when grown in the laboratory. We found that hydrogen is available in the gastric mucosa of mice and that its use greatly increased the stomach colonization by H. pylori. Hydrogenase activity in H. pylori is constitutive but increased fivefold upon incubation with hydrogen. Hydrogen concentrations measured in the stomachs of live mice were found to be 10 to 50 times as high as the H. pylori affinity for hydrogen. A hydrogenase mutant strain is much less efficient in its colonization of mice. Therefore, hydrogen present in animals as a consequence of normal colonic flora is an energy-yielding substrate that can facilitate the maintenance of a pathogenic bacterium.  相似文献   

12.
In examining the potential role of hydrogen in the energy economy of the future, we take an optimistic view. All the technology required for implementation is feasible but a great deal of development and refinement is necessary. A pessimistic approach would obviously discourage further thinking about an important and perhaps the most reasonable alternative for the future. We have considered a limited number of alternative energy systems involving hydrogen and have shown that hydrogen could be a viable secondary source of energy derived from nuclear power; for the immediate future, hydrogen could be derived from coal. A hydrogen supply system could have greater flexibility and be competitive with a more conventional all-electric delivery system. Technological improvements could make hydrogen as an energy source an economic reality. The systems examined in this article show how hydrogen can serve as a general-purpose fuel for residential and automotive applications. Aside from being a source of heat and motive power, hydrogen could also supply the electrical needs of the household via fuel cells (19), turbines, or conventional "total energy systems." The total cost of energy to a residence supplied with hydrogen fuel depends on the ratio of the requirements for direct fuel use to the requirements for electrical use. A greater direct use of hydrogen as a fuel without conversion to electricity reduces the overall cost of energy supplied to the household because of the greater expense of electrical transmission and distribution. Hydrogen fuel is especially attractive for use in domestic residential applications where the bulk of the energy requirement is for thermal energy. Although a considerable amount of research is required before any hydrogen energy delivery system can be implemented, the necessary developments are within the capability of present-day technology and the system could be made attractive economically .Techniques for producing hydrogen from water by electrolysis, from coal, and directly from thermal energy could be found that are less expensive than those now available; inexpensive fuel cells could be developed, and high-temperature turbines could be used for the efficient conversion of hydrogen (and oxygen) to electricity. The use of hydrogen as an automotive fuel would be a key factor in the development of a hydrogen energy economy, and safe storage techniques for carrying sufficient quantities of hydrogen in automotive systems can certainly be developed. The use of hydrogen in automobiles would significantly reduce urban pollution because the dispersed fossil fuel emissions would be replaced by radioactive wastes generated at large central stations. The conversion of internal or external combustion engines for combustion of hydrogen fuel would probably have less economic impact on the automotive industry than the mass introduction of electric automobiles. However, this is a subject that requires more detailed study. All of the safety aspects of hydrogen utilization will have to be examined, especially the problems of safety in the domestic use and the long distance transport of hydrogen in pipelines at high pressures. It is our opinion that the various energy planning agencies should now begin to outline the mode of implementing hydrogen energy delivery systems in the energy economy. The initial transition to hydrogen energy derived from available fossil fuels such as coal should be considered together with the long range view of all the hydrogen being derived eventually from nuclear energy. By the year 1985 when petroleum imports may be in excess of the domestic supply, these plans could set the stage for the transition period from fossil to a predominantly nuclear energy economy able to supply abundant synthetic fuels such as hydrogen. Synthetic fuels will obviously be more expensive than fuels now derived from petroleum; however, there may be no other viable choice. Thus, it is essential that the analysis and technological feasibility of a hydrogen energy system be considered now. It is of vital importance to the nation to develop some general-purpose fuel that can be Produced from a variety of domestic energy sources and reduce our dependence on imported oil.  相似文献   

13.
水稻白叶枯病菌内源过氧化氢的产生及定位   总被引:1,自引:0,他引:1  
采用辣根过氧化物酶-酚红法定量检测病原菌细胞内源过氧化氢的产生,并通过组织化学法观察细胞中过氧化氢积累的亚细胞定位.结果表明:辣根过氧化物酶-酚红法及组织化学染色法均检测到水稻白叶枯病菌内源过氧化氢的产生.透射电子显微镜观察结果和辣根过氧化物酶-酚红法定量检测结果均显示,过氧化氢在水稻白叶枯病菌细胞中普遍存在,不同病原菌内源过氧化氢的水平有极显著差异.病原菌细胞中过氧化氢的积累主要定位在细胞壁.  相似文献   

14.
裂褶菌液体和固体培养产漆酶的比较研究   总被引:2,自引:0,他引:2  
裂褶菌GGHN08-104是产漆酶能力强,且产酶速度快的菌株.对其在液体培养基、固体培养基中产生漆酶的能力和规律进行了研究.结果表明,该菌株在C/N比为70/1,初始pH值为5,Cu2+离子浓度为21 mg/L的液体培养基中酶活最高,达477.94U/mL( 12 d).固体培养时以配方①(棉籽壳31.14%、木屑66.86%、蔗糖1%、石膏1%)产酶活性和效率最高,分别为2449.02U/g和272.11 U/g·d-1,固体发酵产酶效率是液体发酵的6.83倍,因此固体培养更适宜该菌株产漆酶.  相似文献   

15.
为获取具有抑菌活性的海南文昌鸡源乳酸菌,笔者以海南文昌鸡的肠道粘膜及内容物为样品分离乳酸菌。通过菌株形态观察,革兰氏染色镜检、过氧化氢试验和16S rRNA基因序列测序鉴定乳酸菌;而后利用乳酸菌对酸和胆盐的耐受性及其抑菌试验从中筛选出热带动物肠道源抑菌乳酸菌。本研究共获得17株乳酸菌,分别为13株植物乳杆菌和4株粪肠球菌,其中植物乳杆菌对金黄色葡萄球菌、大肠杆菌和鼠伤寒沙门氏菌均有较高抑制作用,有一定耐酸耐胆盐的能力;粪肠球菌抑菌效果均较差。研究结果表明,筛选获得的海南文昌鸡源植物乳杆菌S4-1综合抑菌效果较好,可用于畜禽肠道益生菌制剂开发的后续研究。  相似文献   

16.
[目的]从广西喀斯特生境台湾相思采集根瘤并分离纯化菌株,研究其生理生化特性和生长适应性。[方法]分离纯化从台湾相思树根瘤中获得的菌株,分别对获得的45株菌进行生理生化试验和耐盐、耐钙、酸碱试验及温度试验。[结果]所有供试菌株在B.T.B反应中均产酸,都能利用KNO3和(NH4)2HPO4这2种氮源,绝大部菌株均能利用7种碳源,但在以不同糖类作为唯一碳源时生长速度差别很大;有17株菌呈革兰氏阳性,其余为阴性;有8株菌能利用3-酮基乳糖,19株菌能水解淀粉,19株菌水解明胶,绝大部分菌株都能利用柠檬酸盐;80%供试菌株在牛肉膏蛋白胨培养基上生长很差;耐低温(9℃)的菌株有19株,占总数的42.2%,耐高温(39℃)较强的菌株有28株;13株菌的耐酸性较强,22株菌在pH 9.0的培养基上生长良好;供试的45株菌都能耐受0.5%的NaCl,在1.0%~2.0%盐浓度范围内能良好生长的菌株有10株;所有供试菌株在3%~15%的钙浓度范围内均生长良好,在30%的钙浓度下仍生长良好的菌株有15株。[结论]在喀斯特环境下,根瘤细菌的生理生化特性及抗逆性表现出多样性。  相似文献   

17.
外生菌根真菌作为森林生态系统的组成部分,参与植物的养分吸收和利用。试验以彩色豆马勃(Pisolithus tinctorius,Pt)和松乳菇(Lactarius deliciosus,Ld)作为供试菌株,以土壤作为培养基唯一钾源,采用液体培养的方法,研究不同锰离子质量浓度下2株供试菌株活化土壤难溶性钾的能力与机理。结果显示,2株外生菌根真菌的生物量随锰离子质量浓度升高而减低,生长受到显著(P<0.05)抑制。在相同锰离子质量浓度下,菌株Pt的菌丝生物量均大于Ld,说明Pt的抗锰能力强于Ld。2株外生菌根真菌均分泌草酸和乙酸,培养基中的pH下降。同时,2株外生菌根真菌均能降低土壤中矿物结构钾的含量,并增加土壤中交换性钾含量,说明在锰离子胁迫下,外生菌根真菌能活化土壤中的难溶性钾。相关分析表明,培养液中草酸分泌量与土壤交换性钾含量呈极显著(P<0.01)正相关,与土壤矿物结构钾含量呈显著(P<0.05)负相关,培养基中的pH与土壤中交换性钾含量呈极显著(P<0.01)负相关。推测外生菌根真菌分泌的有机酸和氢离子有利于土壤难溶性钾的活化,其中草酸可能起到关键作用。由于有机酸和氢离子的分泌量不同,2株外生菌根真菌对土壤难溶性钾的活化能力存在差异。  相似文献   

18.
[目的]建立胆固醇氧化酶的快速鉴定方法。[方法]采用初筛和复筛试验,从21种不同来源的样品中筛选出9株高酶活胆固醇氧化酶菌株,采用定性平板检测法、过氧化氢法、羟醛反应法、薄层层析法等定性检测胆固醇氧化酶的活性。[结果]从21种样品中共筛选出48株胆固醇氧化酶菌株,用定性平板检测法从中筛选出9株高酶活菌株(2-6、15-3、3-3、16-5、3-4、4-3、4-6、JM109和10192),其中4.6酶活最高;过氧化氢法共鉴定出6株高酶活菌株,与定性平板法检测结果一致;薄层层析法可定性检测出胆固醇氧化的唯一产物胆甾4-烯-3-酮。[结论]定性平板检测法和薄层层析法可快速、有效的鉴定出高酶活胆固醇氧化酶菌株。  相似文献   

19.
从野生沙棘果上分离出了5株天然酵母菌,并对这些酵母菌的产酒精能力进行糖度、酒石酸、温度的3因素3水平正交发酵试验。以菌体的OD600值和发酵终了时产酒精量作为评价指标进行分析,初步得出如下结论:①这5株菌株在20%的糖度发酵液中生长不好;②大部分的菌株耐酒石酸(2%)能力不强;③菌体浓度与产酒精量很难找到确定的线性关系;④这5株菌株产酒精的能力较弱。产酒发酵可能不是沙棘果上天然酵母菌利用的最好途径,其发酵液的低酒精度特点,可以作为沙棘发酵饮料进行探索。  相似文献   

20.
宁波地区贝类产品中副溶血弧菌的分离与鉴定   总被引:1,自引:0,他引:1  
从2007年3月至6月,在宁波市5个不同的农贸市场共采集贝类样品360份,分离菌株71株,其中5株代表菌株革兰氏染色阴性、弧状、具极生单鞭毛,利用葡萄糖、甘露醇产酸,不利用乳糖、蔗糖,精氨酸双水解酶阴性,VP试验为阴性,赖氨酸脱羧酶、鸟氨酸脱羧酶为阳性,靛基质、甲基红试验阳性,不产生H2S,初步判断为副溶血弧菌;进一步进行了基于16S rRNA和toxR序列的PCR检测,序列测定结果验证了该5株细菌确实为副溶血弧菌.以16S rRNA序列为基础,分析了分离株与相关细菌菌株的同源性,构建了系统发育树.  相似文献   

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