消炎抗菌片的抗菌活性及对福氏志贺氏菌的抗菌机制初步探讨

目的:研究武汉大学人民医院院内制剂消炎抗菌片对14种不同菌株的抑菌活性,并初步探讨其对福氏志贺菌(Shigella flexner)的抑菌机制。方法:采用K-B法和液体二倍稀释法,测定消炎抗菌片对14种常见致病菌株的抑菌活性,并以药物敏感性较强且与药物主要临床疗效相关的福氏志贺菌为受试菌,从药物对该细菌生长特性的影响、电导率变化,以及SDS聚丙烯酰胺凝胶电泳(SDS-PAGE)谱带,考察给药后菌体变化情况。结果:消炎抗菌片对福氏志贺菌、铜绿假单胞杆菌、藤黄微球菌、大肠杆菌、金黄色葡萄球菌等14个菌种及菌株具有不同程度的抑制作用,总体对革兰阴性菌抑菌效果比革兰阳性菌强;药物作用福氏志贺菌后,菌悬液电导率与对照组相比显著升高,SDS-PAGE结果显示经消炎抗菌片处理的菌体无明显蛋白条带形成。结论:本院院内制剂消炎抗菌片对14种菌株具有不同程度的抗菌活性,能够显著影响福氏志贺菌的细胞膜通透性,且对菌体蛋白具有一定抑制作用。     

莫西沙星纳米药物对耐药铜绿假单胞菌的抑菌活性及其机制

采用纳米沉淀自组装法制备莫西沙星(MXF)纳米粒,对比研究MXF和载药纳米粒对铜绿假单胞菌的抑菌效果及抗菌机制。考察MXF纳米粒的粒径和电位等理化性质、体外释药特性,以及对正常支气管上皮细胞HBE细胞活性的影响,通过最低抑菌浓度(MIC)值测定实验、生物膜形成抑制实验及透射电镜考察其体外抗菌活性并初步探索其抗菌机制。结果表明,该纳米粒的粒径为332.5±2.7 nm,多分散指数(PDI)为0.125±0.053,电位为-24.3±1.7 mV,粒径大小分布均匀,载药量为(6.02±1.27)%,包封率为(16.69±1.17)%,为类球形结构。在磷酸盐缓冲液中,该纳米粒中MXF能够有效快速释放, 24 h内释放约70%, 72 h内释放量可达87%。同时,与MXF游离药物相比,其MIC值为8μg·mL^-1,是MXF溶液的1/2,可显著抑制细菌生物膜的形成,具有较强的抗菌活性,且能靶向至细菌表面发挥药效,提高抗菌效果。本研究中制备的MXF纳米粒的粒径大小分布均匀,具有良好的体外释药性能和抗菌效果,为细菌性肺部感染的治疗及新型抗菌纳米制剂的研发提供了新的研究思路和策略...     

艾叶水提物对大肠杆菌的抑制活性及作用机制研究

目的 研究艾叶水提物对大肠杆菌的抑制活性及作用机制。方法 采用琼脂糖扩散法测定艾叶水提物对大肠杆菌的抑菌活性,采用微量倍比稀释法测定艾叶水提氯仿部位的最小抑菌浓度和最低杀菌浓度,并通过测定细菌细胞膜通透性、胞内组分渗漏、扫描电子显微镜、流式细胞仪等方法对其抑菌机制进行了探讨。结果 结果表明,艾叶水提氯仿萃取物对大肠杆菌具有明显的抗菌作用,最小抑菌浓度为5 mg·mL^-1,最低杀菌浓度为15 mg·mL^-1。作用机制研究表明,在一定浓度下,该萃取物能破坏大肠杆菌的细胞壁,增加细胞膜的通透性,但不能在短时间内杀灭大肠杆菌。扫描电子显微镜证明,该萃取物可使大肠杆菌长时间处于凋亡状态,干扰细胞的正常生理代谢,最终导致细菌死亡。结论 艾叶水提氯仿部位具有明显抑制大肠杆菌的活性,本研究结果为揭示艾叶中非挥发性成分的抗菌活性提供了科学依据,为进一步开发和利用艾叶奠定了实验基础。     

临床常见抗菌药物不合理应用现象与对策

目前，临床抗菌药物不合理使用的现象比较突出，常见抗菌药物不合理使用现象包括抑菌药与杀菌药配伍使用、喹诺酮类抗菌药物与含多价金属离子的药物配伍、喹诺酮类抗菌药物与氨茶碱配伍、对儿童使用喹诺酮类抗菌药物、青霉素与葡萄糖注射液配伍、氨基苷类抗菌药物结膜下注射、第1代头孢菌素与氨基苷类药物配伍、作用机制相同的抗菌药物联用、用药时间过长、氨基苷类抗菌药物与中枢性肌松药配伍使用、特非那定与大环内酯类抗菌药物配伍使用等。医院应加强对医师和药师合理使用抗菌药物知识的培训，加强对抗菌药物不良反应和细菌耐药性的监测，还应加强对抗菌药物使用的管理，以促进临床合理使用抗菌药物。     

中药久灵膏抗菌作用研究

目的 探讨久灵膏的抗菌作用.方法 制备不同浓度的含药营养琼脂培养基和含药营养肉汤培养基,观察久灵膏的最低抑菌浓度(MIC)和最低杀菌浓度(MBC);用兔烫伤皮肤感染抑菌实验来观察久灵膏的体内抗菌作用.结果 1)久灵膏的MIC和MBC分别为2.0%～3.0%及3.0%～6.0%.2)对实验动物显示有较好的抗菌、抗感染作用.结论 久灵膏体内和体外均有不同程度的抑菌和杀菌作用.     

阿奇霉素致过敏性休克2例

阿奇霉素为林可霉素的衍生物，抗菌谱与红霉素相同，对革兰阴性球菌、杆菌、厌氧菌及衣原体、支原体等有强大的抗菌活性，对革兰阳性菌具更强抗菌活性。其作用机制是与细菌核糖体50S亚基结合，抑制蛋白质的合成。本品系抑菌药，因其组织细胞渗透能力强、分布浓度高、抗菌效果好、耐受性好而应用于临床。     

含三苯胺衍生物取代钌配合物的合成及其抗菌活性研究

目的 以三苯胺取代邻菲啰啉衍生物为主配体，合成了两种新型的抗菌钌配合物[Ru(phen)2PMA](PF6)2(Ru-1)和[Ru(dmphen)2PMA](PF6)2(Ru-2)。方法 通过¹HNMR、¹³CNMR和HRMS对两个化合物的结构进行了表征，并通过最低抑菌浓度，生长曲线，时间杀伤曲线，生物膜形成实验，耐药测试，溶血毒素分泌实验以及棋盘联用实验研究了化合物的抗菌活性；通过DAPI/PI染色实验以及蛋白质泄露实验研究了化合物的抗菌机制；最后通过大蜡螟幼虫研究了化合物的毒性。结果 两个化合物在体外对金黄色葡萄球菌均具有显著抗菌活性(MIC=0.0078～0.0156 mg/mL),0.031 mg/mL的Ru-2能在10 min杀灭超过99.0%的细菌。在亚抑菌浓度下，Ru-2不仅能有效抑制细菌生物膜的形成和溶血毒素的分泌，还能显著提升8种临床常用抗生素对金黄色葡萄球菌的敏感性(FICI<0.5)。抑菌机制研究结果表明，化合物Ru-2能破坏细菌细胞壁的完整性。此外，毒性研究也表明Ru-2具有良好的生物相容性；结论 具有膜破坏机制...     

抗菌增敏药药效学非临床研究技术指南

抗菌增敏药是一类本身并不具有抗菌作用的药物，但是其与抗菌药物联合应用后可增加抗菌药物的抗菌活性。抗菌增 敏药是抗菌药物研究领域的新的研究方向，它的非临床研究的药效学内容同样包括体内和体外两个方面。在体外研究中，评价指 标除包括与其他单一抗菌药物评价相同的指标如MIC、MBC、KCs、PAE和ED50，还需要做联合用药后联合抑菌指数(FICI)和联合 时间-杀菌曲线的研究。在体内研究中，评价指标同单一抗菌药物评价指标，但是需要特别注意联合用药药物的配伍剂量的选择。 本技术指南对抗菌增敏药非临床研究药效学的内容及方法进行论述，旨在为抗菌增敏药的临床前药效学研究提供参考。     

N-芳酰烷基环丙沙星的合成及其抗菌活性

通过在环丙沙星7位的哌嗪环上引入脂溶性基团，以寻求抗菌谱更广、疗效更强、毒副作用更小的抗菌药物。根据前药设计原理，设计合成目标化合物，并研究其生物活性。获得了10种新化合物。新化合物的结构经¹H NMR，¹³C NMR，MS和元素分析确证。目标化合物比环丙沙星具有更好的脂溶性；体外抗菌活性研究表明，大部分目标化合物对大肠埃希氏菌和铜绿假单孢菌具有较强的抑菌活性，其中化合物3d对大肠埃希氏菌抑菌活性高于环丙沙星。     

抗菌药物后效应与临床合理用药

抗菌药物后效应（post-antibiotics effect，PAE）是指细菌与抗菌药物短暂接触，当药物浓度降至最低抑菌浓度（MIC）以下或被消除后，细菌的生长仍受到持续抑制的效应。传统的抗菌药物临床给药方案主要是依据平均抑菌浓度（MIC）、最小杀菌浓度（MBC）与血药浓度、半衰期、清除率、组织分布等药动学参数来确定给药剂量和给药间隔，而忽略了药物对细菌繁殖规律的影响及人体免疫机制在杀灭细菌过程中所起的作用。而PAE理论则指出，确定抗菌药物的给药间隔应根据药物浓度超过MIC或MBC的时间加上PAE的持续时间，从而可延长给药间隔，减少药物剂量，起到既不影响疗效又可降低药物不良反应，提高患者依从性，并可实现降低费用的目的。随着对PAE研究的深入，发现多种抗菌药物都具有PAE。目前PAE已成为评价新的抗菌药物、设计合理给药方案的重要参考指标。笔者综合有关文献，对抗菌药物后效应的研究和临床给药方案中的应用作一简明阐述，旨在为优化临床给药模式，设计更加合理有效的抗菌药物给药方案提供理论依据。     

Synthesis and microbial evaluation of novel N(1)-Arilidene-N(2)-t(3)-methyl-r(2),c(6)-diaryl-piperidin-4-one azine derivatives

Some novel N(1)-arylidene-N(2)-t(3)-methyl-r(2),c(6)-diarylpiperidin-4-one azine derivatives were synthesized and their antibacterial activity against Streptococcus faecalis, Bacillus subtilis, Escherichia coli, Pseudomonas aeruginosa, and Staphylococcus aureus and antifungal activity against Candida-6, Candida-51, Aspergillus niger, and Aspergillus flavus evaluated.     

Antibacterial,antifungal, and antimycobacterial activity of Ilex aquifolium leaves

The objective of this study was to examine antibacterial, antifungal, and antimycobacterial properties of Ilex aquifolium L. (Aquifoliaceae) growing in Turkey. The ethanol, ethyl acetate, chloroform, and n-hexane extracts prepared from the leaves of I. aquifolium were tested against Escherichia coli, Staphylococcus aureus, Pseudomonas aeruginosa, Enterobacter aerogenes, Proteus vulgaris, Salmonella typhimurium, and Candida albicans for antibacterial and antifungal evaluation using the microdilution broth susceptibility assay. In addition, antimycobacterial activity of the crude extracts of I. aquifolium was evaluated by microplate Alamar blue assay. The results showed that the extracts tested, except n-hexane, possessed moderate antibacterial and antifungal activity varying from 62.5 to 250?μg/mL. On the other hand, the ethanol extract of the leaves exhibited a minimum inhibitory concentration value (MIC) against Mycobacterium tuberculosis H₃₇Ra strain of 200 μg/mL.     

Characterization of the phenolic composition and antimicrobial activities of Turkish medicinal plants

In this paper, antibacterial and antimycobacterial activity of five Labiatae plant methanol extracts, commonly used for treating cold, stomachache, and sore throat, Salvia fruticosa Mill., Salvia tomentosa Mill., Sideritis albiflora Hub.-Mor. (endemic), Sideritis leptoclada O. Schwarz & P.H. Davis, (endemic), and Origanum onites L., were investigated, and their phenolic compounds were determined by HPLC. Antibacterial activity was analyzed against Staphylococcus aureus, Staphylococcus epidermidis, Enterococcus faecalis, Bacillus cereus, Escherichia coli, Salmonella typhimurium, Enterobacter aerogenes, and Klebsiella pneumoniae. Antimycobacterial activity was assayed against Mycobacterium tuberculosis. The best antibacterial activity (MIC 640 μg/mL) was shown against S. typhimurium and E. aerogenes by S. fruticosa; E. coli, and S. typhimurium, E. aerogenes by S. tomentosa; S. typhimurium, and E. aerogenes by S. leptoclada and S. typhimurium, E. aerogenes and S. epidermidis by O. onites, respectively. The best antimycobacterial activity (MIC 196 μg/mL) was shown by S. tomentosa. S. fruticosa (MIC 392 μg/mL) and O. onites (MIC 784 μg/mL) showed moderate activity against M. tuberculosis. S. albiflora, with low level rosmarinic acid and carvacrol content, showed inhibition against bacteria except K. pneumoniae, B. cereus and M. tuberculosis. The correlation between in vitro activity and ethnobotanical usage was evaluated.     

Progress and prospects in the management of bacterial infections and developments in Phytotherapeutic modalities

The advent of antibiotics revolutionized medical care resulting in significantly reduced mortality and morbidity caused by infectious diseases. However, excessive use of antibiotics has led to the development of antibiotic resistance and indeed, the incidence of multidrug-resistant pathogens is considered as a major disadvantage in medication strategy, which has led the scholar's attention towards innovative antibiotic sources in recent years. Medicinal plants contain a variety of secondary metabolites with a wide range of therapeutic potential against the resistant microbes. Therefore, the aim of this review is to explore the antibacterial potential of traditional herbal medicine against bacterial infections. More than 200 published research articles reporting the therapeutic potential of medicinal plants against drug-resistant microbial infections were searched using different databases such as Google Scholar, Science Direct, PubMed and the Directory of Open Access Journals (DOAJ), etc., with various keywords like medicinal plants having antibacterial activities, antimicrobial potentials, phytotherapy of bacterial infection, etc. Articles were selected related to the efficacious herbs easily available to local populations addressing common pathogens. Various plants such as Artocarpus communis, Rheum emodi, Gentiana lutea L., Cassia fistula L., Rosemarinus officinalis, Argemone maxicana L, Hydrastis canadensis, Citrus aurantifolia, Cymbopogon citrates, Carica papaya, Euphorbia hirta, etc, were found to have significant antibacterial activities. Although herbal preparations have promising potential in the treatment of multidrug-resistant bacterial infection, still more research is required to isolate phytoconstituents, their mechanism of action as well as to find their impacts on the human body.     

Total Phenolic Content,Antioxidant, and Antibacterial Activity of Rumex crispus Grown Wild in Turkey

Abstract

In the current study, we evaluated total phenolic content, antioxidant activity (by using β -carotene bleaching assay), and antibacterial activity of aqueous and methanol extracts of the aerial part of the Rumex crispus L. (Polygonaceae) naturally grown in the Eastern Anatolia region of Turkey. The aerial part of the plant had high total phenolic content (56.31 μ g/mg DW). The antioxidant activity of aqueous and methanol extracts of the aerial part of R. crispus L., BHA, and BHT were found to be 92.35%, 95.49%, 98.16%, and 96.66%, respectively. Although the antioxidant activity of the aqueous and methanol extracts of R. crispus was lower than that of the BHA and BHT, the difference between these was not statistically significant, p < 0.05. The methanol extract possessed strong antibacterial activity against Agrobacterium tumefaciens, Bacillus cereus, Bacillus subtilis, Pseudomonas corrugate, Pseudomonas syringae pv. tomato, Salmonella typhimurium, Serratia liquefaciens, Vibrio cholerae, Yersinia frederiksenii, and Yersinia pseudotuberculosis. Therefore, the aerial part of R. crispus can be used as an effective and safe source of antioxidants and antibacterial agent.     

Synthesis of novel analogues on the α-carbon of houttuyfonate and SAR analysis of antibacterial activity with MOPAC

Three novel α-carbon derivatives of houttuyfonate—HOU-C₈C₁, HOU-C₈C₂, and HOU-C₈C₄—were designed and synthesized, and tested for their in vitro antibacterial activities against seven bacterial strains. A set of molecular properties of houttuyfonate and its five analogues were analyzed by MOPAC. Results indicated that the antibacterial activity of HOU-C₈C₁ is lower than that of HOU-C₈. However, among HOU-C₈C _n (n = 1, 2, 4), as the hydrophobicity increased so did the activity, especially against Gram-positive bacteria. For the isomeric compounds HOU-C₈C₂ and HOU-C₁₀, HOU-C₈C₄, and HOU-C₁₂, the more negative the charges on carbon atom 2, the stronger the antibacterial activity exhibited. This suggests that the C(2) position is the antibacterial active center of houttuyfonate analogues, and that the weak antibacterial activities are possibly caused by the net negative charges on houttuyfonate homologues.     

Antibacterial activity of some Indian medicinal plants

Aqueous extracts of ten medicinal plants were examined for their antibacterial potential against some reference strains of human pathogenic bacteria. Anethum graveolens, Elettaria cardamomum, Foeniculum vulgare, Trachyspermum ammi and Viola odorata were found to be better/equally effective compared to standard antibiotics. V. odorata was the most effective antibacterial with minimum inhibitory concentration values ranging from 1 to 2%. The results provide a scientific basis for the centuries-old usage of aqueous extracts of these medicinal plants.     

Synthesis and antimicrobial activities of N-chloroacetyl-2,6-diarylpiperidin-4-ones

An array of new N-chloroacetyl-2,6-diarylpiperidin-4-ones has been synthesised and their antibacterial activity against Staphylococcus aureus, Escherichia coli, Bacillus subtilis, Pseudomonas aeruginosa, and Salmonella typhi, and antifungal activity against Cryptococcus neoformans, Candida albicans, Rhizopus sp., Aspergillus flavus, and Aspergillus niger examined. Compounds 14 against P. aeruginosa, 15 against S. typhi, 16 against S. aureus, and 19 against B. subtilis showed marked antibacterial activity. Similarly, compounds 15 and 19 against A. niger and 19 against A. flavus exerted significant antifungal activities.     

Design,Synthesis, and Pharmacological Investigation of Iodined Salicylimines,New Prototypes of Antimicrobial Drug Candidates

A series of 3,5‐diiodo‐salicylalidene Schiff bases (compounds 1–35 ) has been synthesized and tested for antimicrobial activity. The compounds were assayed for antibacterial activities by the MTT method. Some of the compounds inhibit the growth of a broad range of bacteria including the species of Bacillus subtilis, Staphylococcus aureus, Streptococcus faecalis, Pseudomonas aeruginosa, Escherichia coli, and Enterobacter cloacae. Among them, compounds 2‐[(4‐chloro‐phenylimino)methyl]‐4,6‐diiodo‐phenol 11 and 2,4‐diiodo‐6‐[(2‐morpholin‐4‐yl‐ethylimino)methyl]phenol 19 showed the most potent antibacterial activity with MIC of 3.1, 12.9, 3.3, 6.5, 12.9, 3.3 and 3.2, 12.8, 3.2, 12.8, 12.8, 3.2 μM against B. subtilis, S. aureus, S. faecalis, P. aeruginosa, E. Coli, and E. cloacae, respectively.     

Evaluation of Biological Activity of Turkish Plants. Rapid Screening for the Antimicrobial,Antioxidant, and Acetylcholinesterase Inhibitory Potential by TLC Bioautographic Methods

Using thin-layer chromatography (TLC) bioautography, a total of 58 extracts from various organs (aerial parts, leaves, flowers, fruits, roots) of 16 Turkish plants were tested for their antibacterial, antifungal, acetylcholinesterase inhibitory, antioxidant, and radical scavenging activities. The hexane, CHCl₃/CH₂Cl₂, water, and total MeOH extracts were used. No activity was observed against two Gram-negative bacteria (Escherichia coli and Pseudomonas aureginosa) and the yeast Candida albicans. However, 23 plant extracts, mostly the CHCl₃/CH₂Cl₂ and H₂O-solubles, inhibited the growth of all five Gram-positive bacteria tested, Micrococcus luteus, Bacillus subtilis, Bacillus cereus, Staphylococcus aureus, and Staphylococcus epidermidis. Of the active extracts, the CHCl₃-soluble of the roots of Putoria calabrica (L. fil) DC (Rubiaceae) displayed the highest antibacterial potential. The majority of the CHCl₃/CH₂Cl₂ crude extracts also appeared to inhibit acetylcholinesterase on TLC plates at 100 µg/spot concentration. Particularly active samples were the middle polarity extracts (CHCl₃/CH₂Cl₂) of the leaves of Rhododendron smirnovii Trautv., R. ponticum L., and R. ungernii Trautv. (Ericaceae). β-Carotene, β-carotene/linoleic acid mixture, and 2,2-diphenyl-l-pieryhydrazyl (DPPH) solutions sprayed onto TLC plates were used for detecting antioxidant and radical scavenging properties of the crude extracts. Antioxidant and radical scavenging activities were found to be predominant in highly polar extracts. The water-solubles of all Rhododendron (Ericaceae) and Phlomis (Lamiaceae) species presented the most significant activity.