Antimicrobial activity of clove oil dispersed in a concentrated sugar solution

Essential oil of clove, dispersed (0.4% v/v) in a concentrated sugar solution, had a marked germicidal effect against various bacteria and Candida albicans. Staphylococcus aureus (five strains), Klebsiella pneumoniae, Pseudomonas aeruginosa, Clostridium perfringens, and Escherichia coli inoculated at a level of 10(7) cfu/ml, and C. albicans (inoculum 4.0 x 10(5) cfu/ml) were killed (greater than 99.999%) after 2-7 min in a laboratory broth supplemented with 63% (v/w) of sugar, and containing 0.4% (v/w) of essential oil of clove. Added organic matter (i.e. human or bovine serum) did not impair its antimicrobial activity. Sugar was not necessary for the antimicrobial activity of clove oil, but the concentrated sugar solution provided a good vehicle for obtaining an oil dispersion that is relatively stable for certain practical applications.     

乳酸杆菌代谢产物对引起阴道炎常见细菌的抑制作用的初步探讨

目的探讨乳酸杆菌代谢产物对临床常见引起阴道炎的大肠埃希菌、铜绿假单胞菌、金黄色葡萄球菌、白色念珠菌、伤寒杆菌和肠球菌的抑菌作用。方法采用营养琼脂平板培养基定量涂菌,国际标准药敏杯给药的药敏试验法,检测乳酸杆菌代谢产物对大肠埃希菌、铜绿假单胞菌、金黄色葡萄球菌、白色念珠菌、伤寒杆菌和肠球菌的抑菌环的大小。结果乳酸杆菌代谢产物对大肠埃希菌、铜绿假单胞菌、金黄色葡萄球菌和伤寒杆菌有明显的抑菌作用,对肠球菌、白色念珠菌无抑菌作用。结论在临床上可应用乳酸杆菌及其制剂调节阴道微生态平衡,治疗细菌性阴道炎。     

Antimicrobial activity of clove oil dispersed in a concentrated sugar solution

Essential oil of clove, dispersed (0.4%v/v) in a concentrated sugar solution, had a marked germicidal effect against various bacteria and Candida albicans. Staphyloccus aureus (five strains), Klebsiella pneumoniae, Pseudomonas aeruginosa, Clostridium perfringens , and Escherichia coli inoculated at a level of 10⁷ cfu/ml, and C. albicans (inoculum 4.0×10⁵ cfu/ml) were killed (< 99.999%) after 2–7 min in a laboratory broth supplemented with 63% (v/w) of sugar, and containing 0.4% (v/w) of essential oil of clove. Added organic matter (i.e. human or bovine serum) did not impair its antimicrobial activity.
Sugar was not necessary for the antimicrobial activity of clove oil, but the concentrated sugar solution provided a good vehicle for obtaining an oil dispersion that is relatively stable for certain practical applications.     

Studies on antimicrobial activity, in vitro, of Physalis angulata L. (Solanaceae) fraction and physalin B bringing out the importance of assay determination

Complex physalin metabolites present in the capsules of the fruit of Physalis angulata L. have been isolated and submitted to a series of assays of antimicrobial activity against Pseudomonas aeruginosa ATCC 27853, Staphylococcus aureus ATCC 29213, S. aureus ATCC 25923, S. aureus ATCC 6538P, Neisseria gonorrhoeae ATCC 49226, Escherichia coli ATCC 8739; E. coli ATCC 25922, Candida albicans ATCC 10231 applying different methodologies such as: bioautography, dilution broth, dilution agar, and agar diffusion techniques. A mixture of physalins (pool) containing physalins B, D, F, G inhibit S. aureus ATCC 29213, S. aureus ATCC 25923, S. aureus ATCC 6538P, and N. gonorrhoeae ATCC 49226 at a concentration of 200 mg/microl, using agar dilution assays. The mixture was inactive against P. aeruginosa ATCC27853, E. coli ATCC 8739; E. coli ATCC 25922, C. albicans ATCC 10231 when applying bioautography assays. Physalin B (200 microg/ml) by the agar diffusion assay inhibited S. aureus ATCC 6538P by +/- 85%; and may be considered responsible for the antimicrobial activity.     

Effect of formulation pH and storage temperatures on the preservative efficacy of some gases used as propellants in cosmetic aerosols

The effects of changes in formulation pH and storage temperature on the preservative activities of some aerosol propellants—butane, carbon dioxide, dimethylether and their combinations were investigated. A preservative challenge test method was used to determine the survival rates of Escherichia coli, Pseudomonas aeruginosa, Staphylococcus aureus, Candida albicans and Aspergillus niger at formulation pH levels 5·80, 7·28 and 8·10 and storage temperatures of 20°, 30° and 40°C.
A significant decrease in the pH of formulations was observed with no corresponding changes in the antimicrobial effectiveness when carbon dioxide was incorporated. Alterations in the antimicrobial profiles of these propellants due to changes in formulation pH were dependent on the propellant and the species of the micro-organism, especially when single propellants were used. Results also showed that the propellants exert antimicrobial activities against the various organisms at the three storage temperatures but there were significantly greater inhibitory activities at 40°C. With a combination of 10% butane/dimethylether (1:2) and 10 bar carbon dioxide there were no differences in the degree of microbial inhibition at the various formulation pH levels and storage temperatures. In most cases, the organisms were completely inactivated within 24 h. These findings showed that the combination of butane/dimethylether with carbon dioxide could be used to protect against microbial contamination and spoilage of formulations of different pH levels as well as those meant for storage at different temperatures.     

The activity of p-methoxybenzylisothiocyanate against Neisseria gonorrhoeae,Haemophilus ducreyi,and other microorganisms

p-Methoxybenzylisothiocyanate was isolated from Lepidium bonariense and found to be responsible for the plants antimicrobial and STD activity. MIC determinations were conducted for p-methoxybenzylisothiocyanate on Haemophilus ducreyi, Neisseria gonorrheae, Candida albicans, Bacillus subtilus, Micrococcus luteus, Staphylococcus aureus, Enterobacter sp., Escherichia coli, Klebsiella pneumoniae, and Psuedomanas aeruginosa. An in vitro cellular toxicity assay showed that at 100 microM (17,9 microg/mL) p-methoxybenzylisothiocyanate is not toxic to living cells.     

The NMR-derived solution structure of a new cationic antimicrobial peptide from the skin secretion of the anuran Hyla punctata

Amphibian skin secretions constitute an important source of molecules for antimicrobial drug research in order to combat the increasing resistance of pathogens to conventional antibiotics. Among the various types of substances secreted by the dermal granular amphibian glands, there is a wide range of peptides and proteins, often displaying potent antimicrobial activities and providing an effective defense system against parasite infection. In the present work, we report the NMR solution structure and the biological activity of a cationic 14-residue amphiphilic alpha-helical polypeptide named Hylaseptin P1 (HSP1), isolated from the skin secretion of the hylid frog Hyla punctata. The peptide antimicrobial activity was verified against Candida albicans, Staphylococcus aureus, Escherichia coli, and Pseudomonas aeruginosa, whereas no significant lytic effect was detected toward red or white blood cells.     

Antimicrobial activity of Mitracarpus scaber extract and isolated constituents

The antimicrobial activity of a methanol extract and isolated constituents of Mitracarpus scaber, a species used in folk medicine by West African native people, was evaluated against Staphylococcus aureus and Candida albicans strains. The mitracarpus methanol extract possesses both antibacterial and antimycotic activities (minimum inhibitory concentration-MIC 31.25 and 62.50 microg ml-, respectively). This extract was subsequently fractioned and monitored by bioassays leading to the isolation of seven compounds screened for antibacterial and antimycotic activities. Among these compounds, gallic acid and 3,4,5-trimethoxybenzoic acid inhibited the growth of Staph. aureus (MIC 3.90 and 0.97 microg ml-). 4-Methoxyacetophenone and 3,4,5-trimethoxyacetophenone effectively inhibited C. albicans (MIC 1.95 microg ml-). The other compounds (kaempferol-3-O-rutinoside, rutin and psoralen) which were also isolated showed low antibacterial and antimycotic activities (125-500 microg ml-).     

地衣芽胞杆菌对白色念珠菌等的拮抗作用

目的了解地衣芽胞杆菌在试管内与阴道正常菌群共生关系的情况。方法将地衣芽胞杆菌菌液分别与葡萄球菌、大肠埃希菌、白色念珠菌、德氏乳杆菌混合培养,定量计数各菌在不同时间内单独培养和混合培养时各菌的活菌数。结果地衣芽胞杆菌生长不受金黄色葡萄球菌、白色念珠菌和大肠埃希菌的影响,金黄色葡萄球菌和白色念珠菌在有地衣芽胞杆菌存在的情况下,其生长受到明显的抑制（P〈0.05）;乳杆菌在12-48 h内,有显著的抑制地衣芽胞杆菌生长的作用,而乳杆菌的生长不受地衣芽胞杆菌的存在与否而正常生长。结论地衣芽胞杆菌对金黄色葡萄球菌及白色念珠菌在体外具有明显的拮抗作用,地衣芽胞杆菌对大肠埃希菌、乳杆菌无明显的体外拮抗作用。     

Dicynthaurin: an antimicrobial peptide from hemocytes of the solitary tunicate, Halocynthia aurantium

We isolated a novel antimicrobial peptide, dicynthaurin, from hemocytes of a tunicate, Halocynthia aurantium. The native peptide had a mass of approximately 6.2 kDa and was composed of two 30-residue monomers without sequence homology to any previously identified peptides (ILQKAVLDCLKAAGSSLSKAAITAIYNKIT). Most cynthaurin molecules were C-terminally amidated and were linked covalently by a single cystine disulfide bond. When performed in membrane-mimetic environments, circular dichroism studies of dicynthaurin revealed largely alpha-helical conformations. Dicynthaurin's broad-spectrum activity encompassed Gram-positive (Micrococcus luteus, Staphylococcus aureus, Listeria monocytogenes) and Gram-negative bacteria (Escherichia coli, Pseudomonas aeruginosa), but not Candida albicans, a fungus. Although dicynthaurin was purified from a marine invertebrate, its antimicrobial activity was optimal at NaCl concentrations below 100 mM. This suggests that the antimicrobial actions of this molecule may take place intracellularly (e.g., within a phagosome) rather than extracellularly.     

Antimicrobial activity and composition of the essential oil of Gontscharovia popovii from Iran

The aerial parts of Gontscharovia popovii (B. Fedtsch. and Gontsch.) Boriss. were collected at full flowering stage. The essential oil was isolated by hydrodistillation and analyzed by a combination of capillary GC and GC-MS. Thirty-one components were identified with the main constituent being carvacrol (71.9%), followed by linalool (5.5%), p-cymene (4.5%) and gamma-terpinene (4.4%). The in vitro antimicrobial activity of the essential oil of G. popovii was studied against seven Gram-positive and Gram-negative bacteria (Bacillus subtilis, Enterococcus faecalis, Staphylococcus aureus, Staphylococcus epidermidis, Escherichia coli, Pseudomonas aeruginosa and Klebsiella pneumoniae) and three fungi (Candida albicans, Saccharomyces cerevisiae and Aspergillus niger). The results of the bioassays showed that the oil exhibited strong antimicrobial activity against all the tested fungi and bacteria except for the resistant bacterium Pseudomonas aeruginosa.     

Purification and characterization of an antimicrobial histone H1-like protein and its gene from the testes of olive flounder, Paralichthys olivaceus

An approximately 21?kDa antimicrobial protein was purified from an acidified testis extract of olive flounder, Paralichthys olivaceus, by ion-exchange and C(18) reversed-phase HPLC. A comparison of the N-terminal amino acid sequence with those of other known antimicrobial polypeptides revealed high homology between this antimicrobial protein and other histone H1 molecules; thus, it was designated flounder histone H1-like protein (fH1LP). fH1LP showed potent antimicrobial activity against Gram-positive bacteria, including Bacillus subtilis, Staphylococcus aureus, and Streptococcus iniae (minimal effective concentrations [MECs], 2.8-30.0?μg/ml), Gram-negative bacteria, including Aeromonas hydrophila, Escherichia coli D31, Vibrio parahaemolyticus (MECs, 1.4-12.0?μg/ml), and Candida albicans (MEC, 2.0?μg/ml). cDNA cloning and tissue distribution studies of fH1LP indicated that it is constitutively expressed in testis and ovary. The fH1LP expression level was significantly dependent on developmental stage, and decreased dramatically after hatching. However, lipopolysaccharide stimulation did not induce fH1LP mRNA in other immune organs, including the kidney and spleen. These results suggest that fH1LP plays an important role in innate immunity in fish during reproduction, including mating, fertilization, and hatching.     

Chemical composition and antimicrobial activity of European propolis

Three propolis samples from Austria, Germany and France were investigated by GC/MS, where eleven compounds were being new for propolis. The samples showed some similarities in their qualitative composition. Phenylethyl-trans-caffeate, benzyl ferulate and galangin were predominant in German propolis. Benzyl caffeate was predominant in French sample. Pinocembrin was predominant in French and Austrian propolis and trans-p-coumaric acid was predominant in all samples. The antimicrobial activity against Staphylococcus aureus; Escherichia coli, and Candida albicans was evaluated. German propolis showed the highest antimicrobial activity against Staphylococcus aureus and Escherichia coli. While Austrian propolis has the highest activity against Candida albicans. French propolis was effective against all pathogens but less than German and Austrian propolis.     

Semisynthesis and antimicrobial activity of novel guttiferone-A derivatives

Six derivatives of guttiferone-A (LFQM-79, 80, 81, 82, 113 and 114) were synthesized and evaluated for their antimicrobial activity against the opportunistic or pathogenic fungi Candida albicans (ATCC 09548), Candida glabrata (ATCC 90030), Candida krusei (ATCC 6258), Candida parapsilosis (ATCC 69548), Candida tropicalis (ATCC 750), Cryptococcus neoformans (ATCC 90012), Trichophyton tonsurans, Microsporum gypseum and also against the opportunistic and pathogenic Gram-positive bacteria Staphylococcus aureus (ATCC 6538), Staphylococcus epidermidis (ATCC 12228), Bacillus cereus (ATCC 11778) and Gram-negative Escherichia coli (ATCC 25922), Pseudomonas aeruginosa (ATCC 9027), Salmonella typhimurium (ATCC 14028), Proteus mirabilis (ATCC 25933). The antimicrobial activities of derivatives were compared with guttiferone-A and they presented to be more potent than the original molecule and sometimes greater than standard drugs established in therapeutics. The current study showed that derivatives of guttiferone-A possess potent antimicrobial activity and are relatively non-cytotoxic, which reveal these new molecules as promising new drug prototype candidates, with innovative structural pattern.     

Egyptian propolis: 1-antimicrobial activity and chemical composition of Upper Egypt propolis

The antimicrobial activity of four propolis samples collected from Upper Egypt against Staphylococcus aureus; Escherichia coli and Candida albicans was evaluated. There was a variation in the antimicrobial activity according to the propolis origin. Banisweif propolis showed the highest antimicrobial activity against Staphylococcus aureus, Escherichia coli and Candida albicans, but Fayoum propolis had moderate activity against all tested pathogens. Propolis collected from Assiut and Souhag gave lower antimicrobial activity. Propolis samples were investigated by GC/MS, 71 compounds were identified, 14 being new for propolis. Banisweif propolis is characterized by the presence of 7 caffeate esters and 4 triterpenoids. Fayoum propolis showed the highest amount of lactic acid and the presence of 3 chalcones. But Assiut propolis is characterized by the presence of 4 prenylated coumarates. Souhag propolis is characterized by the presence of 5 aliphatic dicarboxylic acids and some other new compounds to propolis.     

毛两面针挥发油化学成分及其生物活性

研究了毛两面针挥发油抑菌作用。抗菌实验结果表明,水蒸馏法提取的挥发油对金黄色葡萄球菌、白色念珠菌有明显的抑菌作用,乙醚提取的挥发油原液对金黄色葡萄球菌、大肠杆菌、绿脓杆菌、白色念珠菌有明显的抑菌作用。采用GC/MS分析了水蒸汽所得挥发油的化学成分,鉴定了20种物质,其中,主要成分是倍半萜。(-)-spathulenol、-γelemene和germacrene D等已被报道有抑菌作用的成分含量分别为12.53%、1.75%和1.44%。     

Environmentally benign synthesis and antimicrobial study of novel chalcogenophosphates

We report in this work an environmentally benign zinc mediated synthesis of aryl and benzyl phosphorochalcogenoates in ethanol within a short reaction time. In vitro antimicrobial study along with statistical analysis and seed germination assay were performed. These chalcogenophosphates possess strong antimicrobial activity against the reference strains. The antibacterial activity was determined against four standard strains (Bacilus subtilis, Staphylococcus aureus, Escherichia coli, Pseudomonas aeruginosa). The antifungal activity was evaluated against one fungal strain Candida albicans.     

Chitosan�CEDTA New Combination is a Promising Candidate for Treatment of Bacterial and Fungal Infections

Chitosan is an attractive preparation widely used as a pharmaceutical excipient. This study aimed to evaluate the antimicrobial activities of chitosan derivatives, EDTA, and the newly developed chitosan-EDTA combination against Gram-negative and Gram-positive bacteria as well as Candida albicans. Antimicrobial activity was studied. Both minimal Inhibitory Concentrations (MIC) and minimal biocidal concentrations (MBC) were determined. Chitosan acetic acid recorded lower MIC values against Enterococcus faecalis, Escherichia coli, Staphylococcus aureus, Pseudomonas aeruginosa, and Candida albicans than those exhibited by EDTA. EDTA failed to have inhibitory activity against Enterococcus faecalis as well as MBC against any of the studied microorganisms. Chitosan acetic acid's MBC were recorded to all examined species. Checkerboard assay results indicated a synergistic antimicrobial activity of the new combination against Staphylococcus aureus and an additive effect against other microorganisms. Moreover, a short microbial exposure to chitosan-EDTA (20-30 min) caused complete eradication. Due to the continuous emergence of resistant strains, there is an urgent need to discover new antimicrobial agents. Our findings suggest the use of chitosan as an enhancing agent with antibacterial and antifungal properties in combination with EDTA in pharmaceutical preparations.     

Antimicrobial activity of a series of thiosemicarbazones and their Zn<Superscript>II</Superscript> and Pd<Superscript>II</Superscript> complexes

Thirty-four thiosemicarbazones and S-alkyl thiosemicarbazones, and some of their Zn(II) and Pd(II) complexes were obtained and purified to investigate antimicrobial activity. MIC values of the compounds were determined by the disc diffusion method against Escherichia coli, Klebsiella pneumoniae, Proteus mirabilis, Pseudomonas aeruginosa, Salmonella typhi, Shigella flexneri, Staphylococcus aureus, S. epidermidis, and Candida albicans. The thiosemicarbazones show antibacterial and antifungal effects in free ligand and metal-complex form. Picolinaldehyde-S-methyl- and -S-benzylthiosemicarbazones did not affect the tested microorganisms but their Zn(II) complexes showed selective activity. The antimicrobial activity is relatively high in Me2SO, but the antimicrobial potential is changed in a certain range with Me2SO, HCONMe2, EtOH and CHCl3.     

Investigation and identification of the antimicrobial component of the drug "Tomatol"]

Antimicrobial activity of Tomatol against laboratory strains of Escherichia coli ATCC 25922, Staphylococcus aureus ATCC 6538-P and Candida albicans ATCC 885-653 as well as against clinical isolates of Enterobacter spp., Streptococcus spp., Staphylococcus spp., Klebsiella spp. and Escherichia spp. was tested. Tomatol was shown to have a broad antimicrobial spectrum including gram-positive and gram-negative organisms and Candida. The TLC investigation demonstrated that the Tomatol antimicrobial component was that of a complex of organic acids such as succinic, citric, tartaric and others.