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1.
本文分离在新生儿颊粘膜上皮细胞表面形成微菌落、且初代培养时菌落较纯的15株a溶血细菌,进行对B链球菌、金黄色葡萄球菌、绿脓杆菌、大肠杆菌4种共7株菌的体外拮抗实验。15株菌中包括8株aStrep.,其中Strep.mitis4株,Strep.oralis2株、Strep.Saliv.Salivarius1株、Strep.intermedius1株;LC.lactis.cremoris5株、Gemelamorbilorum1株、Gemelahaemolysans1株。结果约60%(9/15)的颊粘膜定植株对两株及两株以上的病原菌株或阴性杆菌株有拮抗作用,只对1株菌有损坏抗作用的a溶血菌4株,完全无拮抗作用的菌株2株;aStrep.、LC.lactis.cremoris的拮抗作用较强;拮抗作用的有无、强弱有很强的菌株特异性  相似文献   

2.
李聪  陈远腾 《菌物系统》2000,19(1):122-127
本文报道人工增减的一株菌寄生菌属Hypomyces sp.真菌菌体化学成分的研究与分析结果,证明该菌主要次生代谢产物为Bei醌类光敏色素,还含有较丰富的甘露醇和长链烷烃及其衍生物,是一株优良的具有实用开发价值的菌种。  相似文献   

3.
鳗鲡肝肾病病原菌的研究   总被引:33,自引:3,他引:30  
近年来,在广东潮州各养鳗场,每年3-5月和10-12月,广泛流行一种危害严重的鳗鲡肝肾病,给鳗鲡养殖业造成严重损失。本文记述了该病的症状,重点研究鳗肝肾病的病原菌。作者从患肝肾病的病鳗肝脏、肾脏和胃液中分离到10株致病菌。根据分离株的形态、培养、生化特性,8株致病菌特性一致,鉴定为迟饨爱德华氏菌(EdwardsiellatardaEwingetMcwhorter)另外两株菌特性相同被鉴定为运动性Aeronlonassp.。研究结果阐明了鳗鲡肝肾病主要是由E.tarda引起的爱德华氏菌病,部分病例是由E.tarda和运动性Aeromonas菌引起的并发症.E,tarda是鳗鲡肝肾病的病原菌。  相似文献   

4.
从一株抗稻瘟净(BS)的Aspergillus terreus菌中克隆到一个blastieidinS脱氨酶基因,命名为bsrAS。DNA序列分析表明bsrAS不含内含子。编码区长390bp,编码130个氨基酸。将bsrAS转化到稻瘟菌中,能使受体菌表达出BS脱氨酶的活性,从而产生抗药性。该基因可作为抗药标记基因使用,建立稻瘟菌的基因转化系统。  相似文献   

5.
采用紫外照射,化学诱变和原生质融合等方法选育到一株性状更优良的突变株SCB329,并与新筛选的一株芽孢杆菌SCB933搭配组成新的组合菌系,产酸小菌SCB329与其亲本菌株氧化葡萄糖酸杆菌性状相似,伴生大菌SCB933属苏芸金芽孢杆菌(B.thurngiensis),新组合菌系列L-山梨糖的发酵液提取后经纸层析,元素分析和红外吸收光谱等项鉴定,其发酵产物克系2-酮基-L-古龙酸,对新组合菌系的生物  相似文献   

6.
对951个样品分离鉴定,有747个样品含芽孢杆菌,有菌率为78.55%.共分离得到芽孢杆菌1138株,其中苏云金杆菌(Bacillusthuringiensis,简称B.t)143株,占12.5%;球形芽孢杆菌(Bacillussphaericus,简称B.s)11株,占0.97%;其他芽孢杆菌984株,占86.40%.从芽孢杆菌中选出产生晶体、苏云金素或磷酸酯酶C(PhosphalipaseC,简称PLC)的毒素菌株168株,其中B.t占143株,B.s有5株,其他芽孢杆菌10株.在产毒素菌株中,经测定有120株菌对供试昆虫毒性达标.占77.92%.不同菌株的杀虫毒素、杀虫范围和毒力各异,认为这种差异取决于毒素和虫种两方面的特异性.  相似文献   

7.
一株产类胡萝卜素菌株的分离与鉴定   总被引:4,自引:0,他引:4  
本文报道了一株产类胡萝卜素株分离鉴定的结果,根据该菌的形态学特征、培养特征、细胞壁组分析及血清学反应,该菌株应归为红球菌属的一个种(Rhodococcus sp)。  相似文献   

8.
褐腐真菌产生的低分子化合物对纤维素的解聚作用研究   总被引:9,自引:1,他引:8  
王蔚  卢雪梅 《菌物系统》1997,16(1):40-46
糙皮侧耳(Pleurotusostreatus)密粘褶菌(Gloeophyllumtrabeum)洁丽香菇(Lentinuslepideus)等8株褐腐菌在滤纸上进行固体培养时,在培养初期,纤维素的聚合度均呈现大幅度下降,但不表现失重。培养过程中也未能检测出滤纸酶活力,只有少量内切葡聚糖酶活力。而且这8株菌都具有络合F3^3+和产生羟基自由基,OH的能力,由降解和解聚能力最强的密粘褶菌的胞外酶液在  相似文献   

9.
龙血树真菌群及其对血竭形成的影响   总被引:19,自引:0,他引:19  
从柬埔寨龙血树(Dracaenacochinchinensis)茎杆中分离到303株真菌,其中镰刀菌属(Fusarium)菌株占总分离频率的52%,其次是短梗霉(Aureobasidium)和枝孢霉(Cladosporium)。通过活体接种对血竭产生的影响试验表明,对血竭形成起重要作用的真菌主要是禾谷镰刀菌龙血树变种(F.graminumvar.dracaena)等4株红色镰刀菌,可使血竭形成量提高66%-120%。  相似文献   

10.
拮抗菌BS—98分泌抗菌蛋白的条件及其发酵液特性   总被引:7,自引:2,他引:5  
由本室分离得到一株强烈抑制芦笋茎枯病等植物病原真菌的拮抗菌BS—98菌株(Bacillussubtilis)。用环柱法检测该菌株的抗菌活性表明,该菌株除抑制芦笋茎枯病菌PhomaasparagiSacc外,对小麦赤霉病菌(Fusariumgraminearum),棉花枯萎病菌(Fusariumoxysporumfsp.Vasinfectum)、棉花黄萎病菌(Verticillumalbo—atrum)、黄瓜灰霉病菌(Botryti  相似文献   

11.
117例医院真菌感染分析及预防   总被引:1,自引:0,他引:1  
目的 了解佛山市南海人民医院真菌感染的分布,探讨有效预防和控制真菌感染的措施。方法 对该院117例真菌感染病例作回顾性分析。结果 3583例送检标本中真菌检出率为3.27%(117/3583),医院内真菌感染率为2.95%(106/3583)。分离出真菌以白色念珠菌为主(70/117.59.8%)、热带念珠菌次之(17/117,14.5%)、霉菌居第3位(9/117.7.69%)。药敏显示:5-氟胞嘧啶、两性霉素B和制霉素敏感率较高,分别为92.4%、93.3%和92.5%,咪康唑、酮康唑和益康唑敏感率较低.为52.0%、49.0%和36.0%。结论 医院内真菌感染占真菌感染绝大部分,感染真菌以白色念珠菌为主。感染部位以呼吸道为主;临床规范、合理使用广谱抗生素,加强消毒护理工作。是预防控制真菌感染发生的最有效措施。  相似文献   

12.
叶辉  母其爱  吕军  张东华 《昆虫知识》2004,41(6):555-558
云南半帚孢 (Leptogramphyunnanensis)是纵坑切梢小蠹Tomicuspiniperda重要的共生真菌 ,在纵坑切梢小蠹危害寄主树木过程中发挥着重要作用。研究揭示 ,纵坑切梢小蠹主要通过与受到感染云南半帚孢的韧皮组织的接触携带上云南半帚孢的。纵坑切梢小蠹卵、幼虫和蛹对云南半帚孢的带菌率较高 ,均大于 90 % ,而成虫的带菌率较低。纵坑切梢小蠹的体表和体内均携带有云南半帚孢 ,但体表带菌是纵坑切梢小蠹带菌的主要途径。通过对纵坑切梢小蠹成虫头、足、翅和腹部带菌率的研究发现 ,云南半帚孢在纵坑切梢小蠹各部位的分布大体相同 ,揭示纵坑切梢小蠹没有携带云南半帚孢的特化构造或器官。  相似文献   

13.
与盾叶薯蓣细胞共生培养的内生真菌分离及其生物学特性   总被引:1,自引:0,他引:1  
从盾叶薯蓣根状茎中分离到一株与盾叶薯蓣细胞共生培养的内生真菌(RE0105)。测定了该菌ITS1-5.8S rDNA—ITS2序列并构建了系统发育树,发现RE0105与Libertella属形成一个类群,具有较近亲缘关系。该真菌能产生与宿主植物相同的代谢产物——薯蓣皂苷元。对RE0105培养特性研究表明:富含有机营养的培养基有利于其生长;盾叶薯蓣细胞提取物可明显刺激其生长;20μmol/L生长素NAA和2,4-D能够促进RE0105的生长。200μmol/L细胞分裂素KT和BA对RE0105生长具有一定的促进作用,但与生长素相比,细胞分裂素对RE0105生长的刺激作用较小。蔗糖、葡萄糖、果糖、乳糖、木糖和NH4NO3是RE0105生长的良好C源和无机N源,但NH4Cl和(NH4)2SO4对该菌生长具有明显抑制作用,并且显著影响其形态特征。  相似文献   

14.
The treatment of the simulated lead-contaminated solid waste by composting with white-rot fungus was studied at laboratory scale. The composting system without the inocula of white-rot fungus was prepared as control, and the composting of the uncontaminated solid waste with the inocula of white-rot fungus was carried out as the other control. The results indicated that the solid waste inoculated with white-rot fungus could be successfully processed. The final compost was mature with 70.5% of lead (Pb) in residual fraction and none in exchangeable fraction. Germination index reached 120%. All the results indicated that the bioavailability of Pb in compost was reduced and the potential harm of Pb in compost was alleviated by composting with the inocula of white-rot fungus.  相似文献   

15.
A new genus and species is described to accommodate a newly discovered fungus pathogenic to Linnaea borealis. The fungus forms true sclerotia on stems and leaves of its host and apothecia arise singly or gregariously on the surface of ripe sclerotia. The new fungus was collected together with a stromatic conidiomal fungus that occurred on the same host. A putative teleomorph-anamorph connection of the observed taxa was ruled out by sequence comparison of the nuclear ribosomal internal transcribed spacer DNA sequences (ITS rDNA). Based on morphology and pathogenicity, the new fungus belongs in the family Sclerotiniaceae, Helotiales, Ascomycota. A phylogenetic analysis of ITS rDNA sequences from 26 taxa of the family Sclerotiniaceae was performed to conclude on the systematic position of the new fungus. The small tuberoid sclerotia, brownish subsessile to substipitate apothecia, four-spored asci, ellipsoid to isthmoid ascospores, inability to grow on PDA culture media and a number of ITS rDNA sequence autapomorphies characterize and distinguish the fungus from other taxa of the Sclerotiniaceae.  相似文献   

16.
暗褐网柄牛肝菌Phlebopus portentosus与介壳虫形成的菌腔虫瘿是该菌营养机制研究的关键环节。本研究先后在云南、四川和广西3省区暗褐网柄牛肝菌产区的16个地点,对菌腔虫瘿的生态和生物学进行了大量的野外调查。发现根部着生菌腔虫瘿的寄主植物有31种,涉及16个科的28个属。与暗褐网柄牛肝菌形成菌腔虫瘿的介壳虫种类有12种,其中10种隶属粉蚧科Pseudococcidae、绵蚧科Monophlebidae、蚧科Coccidae各1种。在不同的寄主植物上菌腔虫瘿的寄生位置和形状会有所不同,与暗褐网柄牛肝菌菌丝形成菌腔虫瘿的寄主植物和介壳虫之间不存在专一性。上述研究结果为暗褐网柄牛肝菌的仿生栽培奠定了基础。  相似文献   

17.
A manganese-oxidizing fungus was isolated from a hot spring in Japan. The fungus was increasingly effective at oxidizing Mn(II) ions as the concentration of organic carbon sources in the growth medium was decreased. The fungus oxidized 50 ppm of Mn(II) ions within 160 h in a pH 7.3 medium at 25 degrees C. The presence of carbon fiber shortened the time to 80 h, and promoted steady oxidation. The oxidation products were identified by XPS and XRD to be poorly crystallized and amorphous MnO(2), both with and without the fiber. These results suggest that the fiber participates in kinetically limited oxidation. The fungus was entangled with and clung to the fibers, and the oxidized Mn species accumulated on the fungus. Similarly shaped polyethylene telephthalate fiber did not enhance the oxidation, nor was adhesion of the fungus observed. Although the mechanism is still unknown, the present work shows that removal of Mn from solution through the precipitation and accumulation of Mn-oxides on the fungus in the presence of carbon fiber is a promising improvement for water treatment.  相似文献   

18.
The white rot fungus Coriolus versicolor could decolorise reactive dye Remazol Brilliant Violet to almost 90%. The fungal mycelia removed color as well as COD up to 95% and 75%, respectively, in a batch reactor. Decolorising activity was observed during the repeated reuse of the fungus. It was possible to substantially increase the dye decolorising activity of the fungus by carefully selecting the operational conditions such as media composition, age of fungus and nitrogen source. The fungal pellets could be used for eight cycles during the long term operation, where medium and dye was replenished at the end of each cycle and the fungus was recycled. Presence of a nitrogen source and nutrient content of media played an important role in sustaining the decolorisation activity of the fungus. The form of nitrogen source (e.g. peptone vs. urea) was also important to maintain the decolorising activity with peptone showing better decolorisation.  相似文献   

19.
Aims: To degrade ether‐type polyurethane (ether‐PUR), ether‐PUR–degrading micro‐organism was isolated. Moreover, ether‐PUR–degrading mechanisms were analysed using model compounds of ether‐PUR. Methods and Results: A fungus designated as strain PURDK2, capable of changing the configuration of ether‐PUR, has been isolated. This isolated fungus was identified as Alternaria sp. Using a scanning electron microscope, the grid structure of ether‐PUR was shown to be melted and disrupted by the fungus. The degradation of ether‐PUR by the fungus was analysed, and the ether‐PUR was degraded by the fungus by about 27·5%. To analyse the urethane‐bond degradation by the fungus, a degraded product of ethylphenylcarbamate was analysed using GC/MS. Aniline and ethanol were detected by degradation with the supernatant, indicating that the fungus secreted urethane‐bond–degrading enzyme(s). PURDK2 also degraded urea bonds when diphenylmethane‐4,4′‐dibutylurea was used as a substrate. Conclusions: The enzyme(s) from PURDK2 degraded urethane and urea bonds to convert the high molecular weight structure of ether‐PUR to small molecules; and then the fungus seems to use the small molecules as an energy source. Significance and Impact of the Study: Ether‐PUR–degrading fungus, strain PURDK2, was isolated, and the urethane‐ and urea‐bonds–degrading enzymes from strain PURDK2 could contribute to the material recycling of ether‐PUR.  相似文献   

20.
四年间酵母样真菌感染的病原菌分布与耐药特征分析   总被引:4,自引:0,他引:4  
目的了解临床酵母样真菌感染的流行特点及其耐药性,指导临床合理运用抗真菌药物。方法运用WHONET软件对中南大学湘雅三医院4年间临床分离出的酵母样真菌与其耐药进行回顾性分析。结果4年间临床酵母样真菌感染率由2002年的9.0%升至2005年的13.8%,白色念珠菌仍是引起临床感染的主要真菌,但其构成比由2002年的69.7%降至2005年的49.1%,而近平滑念珠菌的构成比4年间增加了9.5%,成为临床酵母样真菌感染的第二位病原菌。4年间临床酵母样真菌对唑类药物的耐药率增加了9.6%~16.8%。结论临床酵母样真菌引起的感染逐年增加,种类增多,对唑类药物的耐药情况日趋严重,应加强对临床真菌感染与耐药性情况的监测,以指导临床合理使用抗生素。  相似文献   

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