Antibacterial activities of the leaf extracts of Eugenia uniflora Linn. (Synonym Stenocalyx michelli Linn.) Myrtaceae

The aqueous, organic, and volatile oil extracts of leaves of Eugenia uniflora Linn. Family Myrtaceae were investigated for antibacterial properties using agar dilution techniques. The aqueous extract was the most active against the organisms compared to the organic and volatile oil extracts. The extracts were found to inhibit Gram positive Staphylococcus aureus and Bacillus subtilis and Gram negative Escherichia coli and Shigella dysentcriae. Pseudomonas aeruginosa, Klebsiella pneumoniac, and Salmonella typhi were not inhibited.     

炭疽芽胞杆菌的感染与生物恐怖

综述了炭疽生物恐怖、炭疽在中国的流行概况、实验室诊断方法的最新进展。同时介绍了炭疽的预防与控制，提出了应对可能发生的生物恐怖应采取的措施。     

消毒剂敌菲特的研究

经全面考察研究,敌菲特缓释消毒灭菌剂具有良好的消毒灭菌效果,对细菌繁殖体、病毒和细菌芽孢均可完全灭活;即使在—20℃低温条件下,对枯黑变种芽孢仍具很好的杀灭效果。此外,该消毒剂基本克服了氯制剂对金属腐蚀性的缺陷;原药性能基本稳定。     

枯草杆菌BF-7658α-淀粉酶生产菌株所产蛋白酶热稳定性研究

我国α—淀粉酶(EC3.2.1.1)生产是用枯草杆菌BF—7658菌株,它产生的酶是个复杂酶系。其中混杂的蛋白酶未见酸性蛋白酶。发酵液经热处理后,测蛋白酶活力。结果,碱性蛋白酶耐热性比中性蛋白酶强。发酵液经55℃,30分钟热处理后,碱性蛋白蛋残存活力与室温(20～25℃)下碱性蛋白酶活力相差不显著(P>0.05),而中性蛋白酶则相差显著(P<0.05)。用电泳法观察发酵液蛋白酶电泳谱型,显示两条蛋白酶区带。     

聚γ-谷氨酸高产突变株的选育及摇瓶发酵条件

对地衣芽孢杆菌(Bacilluslicheniformis)进行亚硝基胍和60Co诱变,获得一株γ PGA的高产菌株C9.γ PGA质量浓度由9.44g/L提高到19.76g/L,提高了109%.突变株传代10次,质量浓度保持基本稳定.通过正交试验和单因素试验对发酵培养基及发酵条件进行了优化.当发酵培养基中含柠檬酸12g/L、甘油80g/L、L 谷氨酸23g/L、氯化铵7g/L,pH7.0,装液量为50mL/250mL三角瓶,接种体积分数为5%时,37℃摇瓶发酵72h,γ PGA达到23.32g/L.     

一株产新型大环内酯抗生素海洋解淀粉芽孢杆菌的分离鉴定

Objective To perform taxonomic studies on a novel macrolactin-producing gram-positive bacterial strain MS1721 isolated from the mud at a depth of 30 m in the East China Sea. Methods Taxonomic studies were conducted based on the phenotypic and BIOLOG analysis, 16S rDNA gene sequencing and blast analysis, and fatty acid components analysis. The antibacterial activity of macrolactin S was determined by evaluation models established in our lab. Results MS1721 strain displayed high similarity with genus Bacillus in similarity values between 97%～99%, in which the nearest neighbor was Bacillus amyloliquefaciens with the similarity value of 99.6%. The predominant fatty acid component was 15:1 iso H/13:0 3OH. Conclusions MS1721 strain belongs to the genus Bacillus, and Bacillus amyloliquefaciens MS1721 was proposed as the name for this strain on the basis of the taxonomic data. The second metabolite-macrolactin s produced by this strain exhibited obvious antibacterial activity.     

Multiple brain abscesses and intracerebral hemorrhage caused by Bacillus Cereus in a case of acute lymphatic leukemia

We report a first case of a 19 year old female suffering from an acute lymphatic leukemia, which developed shortly after the initiation of a chemotherapy an intracerebral hemorrhage and fatal multiple brain abscesses caused by Bacillus cereus. There is much evidence that Bacillus cereus in immunocompromised patients leads to a localized, necrotizing tissue infection due to the production of potent toxins and usually results in rapid and fulminant tissue destruction. Bacillus species has an special affinity for the CNS mediated by phospholipase C, which tends to associate with the lipid membranes of the brain.     

PCR检测结核分枝杆菌DNA中不同细菌裂解方法结果观察

目的：寻找适合于临床ＰＣＲ检测结核杆菌ＤＮＡ简单、快速、有效、经济的细菌裂解方法。方法：采用１１种细菌裂解剂对相同数量的结核分枝杆菌进行裂解，裂解上清液直接用于ＰＣＲ扩增，结果：１％ＴｒｉｔｏｎＸ－１００，１％ＮＰ４０，１％Ｔｅｗｅｅｎ２０、和１％ＯＰ四种裂解剂的裂解液可直接扩增出结核分枝杆菌ＤＮＡ；ＳＤＳ，ＮａＯＨ，十二烷基肌酸钠等裂解剂的裂解液直接用于ＰＣＲ扩增均为阴性。结论：１％的Ｔｒｉｔｏｎｘ－１００，ＮＰ４０、Ｔｅｗｅｅｎ２０和乳化剂ＯＰ裂解细菌效果好，又不抑制ＰＣＲ反应，适合于作为临床ＰＣＲ检测结核杆菌的裂解剂。     

地衣芽胞杆菌对肠道致病菌的体内拮抗作用研究

目的:探讨地衣芽胞杆菌C01在模型小鼠体内对大肠杆菌、沙门氏菌抑制作用以及对乳杆菌等有益菌的促进作用。方法:用地衣芽胞杆菌C01灌胃肠道感染模型小鼠,采用体外活菌培养,分析粪便菌群数量的变化。结果:C01灌胃治疗组(EPEC C01)中乳杆菌的数量显著高于EPEC灌胃模型组(EPEC N)(P<0.01),肠杆菌数量下降极显著(P<0.01),而(EPEC N)组肠杆菌数显著高于正常对照组(NS)(P<0.05);肠炎沙门氏菌处理后C01灌胃治疗组(SL C01)和处理后肠炎沙门氏模型组(SL N)比较,乳杆菌、肠球菌和总厌氧菌的变化不明显,但肠杆菌数量下降极显著(P<0.01);形态病理学观察结果显示,C01芽胞杆菌灌胃治疗组肠粘膜病变明显减轻,肠粘膜及绒毛高度明显增加,绒毛轻度水肿,绒毛排列整齐、致密。结论:地衣芽胞杆菌C01在体内对肠炎沙门氏菌和致病性大肠杆菌有较强的抑制作用,能促进乳杆菌等生理性有益菌的增殖,可保护肠粘膜结构的完整性免受病原菌的侵袭。     

Use of the microorganism Bacillus stearothermophilus as a model to evaluate toxicity of the lipophilic environmental pollutant endosulfan

Microorganisms are very powerful tools for the supply of information about the toxic effects of lipophilic compounds, since an impairment of cell growth usually occurs as a result of perturbations related, in most cases, with the partition of toxicants in membranes. The thermophilic eubacterium Bacillus stearothermophilus has been used as a model system to identify α- and β-endosulfan interactions with the membrane possibly related with the insecticide toxicity. Two approaches have been pursued: (a) bacterial growth is followed and the effects of endosulfan isomers determined; (b) biophysical studies with the fluorescent fluidity probe 1,6-diphenyl-1,3,5-hexatriene (DPH) were performed to assess the effects of α- and β-endosulfan on the organization of the membrane lipid bilayer. The effects on growth were quantitatively evaluated by determination of growth parameters, namely the lag phase, the specific growth rate and the cell density reached by cultures in the stationary phase. Growth inhibition by α and β-endosulfan dependent on the concentration is diminished or removed by the addition of 2.5 m Ca²⁺ to bacterial cultures. Fluorescence DPH polarization consistently showed opposite effects of Ca²⁺ and α- and β-endosulfan on the physical state of bacterial polar lipid dispersions.