RESUMEN
Antifungalmycin N2 (3-methyl-3,5-amino-4-vinyl-2-pyrone, C6H7O2N) was a novel metabolite produced from Streptomyces sp. strain N2, and the present study aimed to evaluate its antibacterial and cytotoxic properties. By using Oxford cup method, the obtained results revealed that antifungalmycin N2 exhibited a significant antibacterial activity against the pathogenic bacteria such as Staphylococcus aureus, Escherichia coli, and Micrococcus kristinae, especially the Gram-positive S. aureus. Meanwhile, the MTT assay showed that antifungalmycin N2 could exert a marked inhibitory action on tumor cell lines, such as the cell lines of BEL-7402 (human hepatocellular carcinoma), Hela (human cervical carcinoma), HCT116 (human colon cancer), and SW620 (human colon cancer). And the IC50 values antifungalmycin N2 against the above cell lines ranged from 11.23 to 15.37 µg/mL. In conclusion, the antibacterial and cytotoxic activities suggested that the novel antifungalmycin N2 was a promising active structure to be developed as new drug for treating infectious diseases and cancers.
Asunto(s)
Antibacterianos/farmacología , Antineoplásicos/farmacología , Streptomyces/química , Antibacterianos/química , Antineoplásicos/química , Línea Celular Tumoral , Descubrimiento de Drogas , Evaluación Preclínica de Medicamentos , Escherichia coli/efectos de los fármacos , Humanos , Pruebas de Sensibilidad Microbiana , Micrococcaceae/efectos de los fármacos , Staphylococcus aureus/efectos de los fármacosRESUMEN
Present study deals with the isolation and characterization of a bacterium capable for the effective reduction of Cr(VI) from tannery wastewater. Based on the 16S rRNA gene sequence analysis, this bacterium was identified as Cellulosimicrobium sp. (KX710177). During the Cr(VI) reduction experiment performed at 50, 100, 200,and 300mg/L of Cr(VI) concentrations, the bacterium showed 99.33% and 96.98% reduction at 50 and 100mg/L at 24 and 96h, respectively. However, at 200 and 300mg/L concentration of Cr(VI), only 84.62% and 62.28% reduction was achieved after 96h, respectively. The SEM analysis revealed that bacterial cells exposed to Cr(VI) showed increased cell size in comparison to unexposed cells, which might be due to either the precipitation or adsorption of reduced Cr(III) on bacterial cells. Further, the Energy Dispersive X-ray (EDX) analysis showed some chromium peaks for cells exposed to Cr(VI), which might be either due to the presence of precipitated reduced Cr(III) on cells or complexation of Cr(III) with cell surface molecules. The bacterium also showed resistance and sensitivity against the tested antibiotics with a wide range of MIC values ranging from 250 to 800mg/L for different heavy metals. Thus, this multi-drug and multi-metal resistant bacterium can be used as a potential agent for the effective bioremediation of metal contaminated sites.
Asunto(s)
Cromo/análisis , Micrococcaceae/aislamiento & purificación , Curtiembre , Aguas Residuales/microbiología , Contaminantes Químicos del Agua/análisis , Purificación del Agua/métodos , Biodegradación Ambiental , Cromo/química , Cromo/toxicidad , Relación Dosis-Respuesta a Droga , Pruebas de Sensibilidad Microbiana , Micrococcaceae/efectos de los fármacos , Micrococcaceae/genética , Oxidación-Reducción , ARN Ribosómico 16S/genética , Aguas Residuales/análisis , Contaminantes Químicos del Agua/química , Contaminantes Químicos del Agua/toxicidadRESUMEN
AIM: To evaluate the antimicrobial activity of hydroalcoholic extracts of pomegranate (Punica granatum L.) peel and juice, against the microorganisms considered the main etiologic agents of dental caries. METHODS: The values of the minimum inhibitory concentration (MIC) and the minimum bactericidal concentration (MBC) were determined against Streptococcus mutans Clarke ATCC® 25175™ strain and Rothia dentocariosa clinical isolate. RESULTS: Peel extracts inhibit effectively the growth and survival of S. mutans ATCC 25175 strain and R. dentocariosa clinical isolate with MIC and MBC values of 10 µg/µl and 15 µg/µl, respectively. Furthermore, the pomegranate juice extract showed high inhibitory activity against S. mutans ATCC 25175 strain with a MIC value of 25 µg/µl and a MBC value of 40 µg/µl, whereas, against R. dentocariosa, it has displayed a moderate inhibitory activity, with MIC and MBC values of 20 µg/µl and 140 µg/µl, respectively. CONCLUSIONS: In vitro microbiological tests demonstrate that the hydroalcoholic extracts of pomegranate juice and peel are able to contrast the main cariogenic bacteria involved in tooth decay. Although being preliminary data, our results suggest that pomegranate polyphenolic compounds could represent a good adjuvant for the prevention and treatment of dental caries.
Asunto(s)
Caries Dental/tratamiento farmacológico , Lythraceae/química , Extractos Vegetales/administración & dosificación , Caries Dental/microbiología , Jugos de Frutas y Vegetales , Humanos , Pruebas de Sensibilidad Microbiana , Micrococcaceae/efectos de los fármacos , Micrococcaceae/patogenicidad , Extractos Vegetales/química , Streptococcus mutans/efectos de los fármacos , Streptococcus mutans/patogenicidadRESUMEN
Rhizobacterial volatile organic compounds (VOCs) play an important role in the suppression of soil-borne phytopathogens. In this study, the VOCs produced by a soil-isolate, Bacillus subtilis FA26, were evaluated in vitro for their antibacterial activity against Clavibacter michiganensis ssp. sepedonicus (Cms), the causal agent of bacterial ring rot of potato. The VOCs emitted by FA26 inhibited the growth of Cms significantly compared with the control. Scanning and transmission electron microscopy analyses revealed distorted colony morphology and a wide range of abnormalities in Cms cells exposed to the VOCs of FA26. Varying the inoculation strategy and inoculum size showed that the production and activity of the antibacterial VOCs of FA26 were dependent on the culture conditions. Headspace solid-phase microextraction/gas chromatography-mass spectrometry analyses revealed that FA26 produced 11 VOCs. Four VOCs (benzaldehyde, nonanal, benzothiazole and acetophenone) were associated with the antibacterial activity against Cms. The results suggested that the VOCs produced by FA26 could control the causal agent of bacterial ring rot of potato. This information will increase our understanding of the microbial interactions mediated by VOCs in nature and aid the development of safer strategies for controlling plant disease.
Asunto(s)
Antibacterianos/farmacología , Bacillus subtilis/metabolismo , Micrococcaceae/efectos de los fármacos , Micrococcaceae/ultraestructura , Compuestos Orgánicos Volátiles/metabolismo , Compuestos Orgánicos Volátiles/farmacología , Acetofenonas/metabolismo , Acetofenonas/farmacología , Aldehídos/metabolismo , Aldehídos/farmacología , Antibacterianos/biosíntesis , Benzaldehídos/metabolismo , Benzaldehídos/farmacología , Benzotiazoles/metabolismo , Benzotiazoles/farmacología , Cromatografía de Gases y Espectrometría de Masas , Pruebas de Sensibilidad Microbiana , Micrococcaceae/crecimiento & desarrollo , Enfermedades de las Plantas/microbiología , Nodulación de la Raíz de la Planta/fisiología , Microbiología del Suelo , Solanum tuberosum/microbiologíaRESUMEN
This study was the first to describe the hitherto deficiently evaluated alkaline tolerance of Kocuria marina isolate from a pediatric patient with continuous intravenous epoprostenol dosing therapy. Our isolate from blood of a 7-year-old Japanese boy was finally identified as K. marina by the morphological, cultural, and biochemical properties together with the comparative sequence analyses of the 16S rRNA genes. The K. marina isolate, the causative agent of catheter-related blood-stream infection, was not only revealed to be salt tolerant (NaCl 15%), but also demonstrated to be stably survived with no apparent decrease of cell counts for long periods (120 h) in an alkaline environment (pH 8, 9, 10, and 11) at 35 °C. Its remarkable tolerance to the stresses of high alkalinity compared with a clinical Staphylococcus aureus strain should provide consistent interpretation that the environment of high alkalinity (pH 10.2-10.8) measures should be insufficient to inactivate almost all the causative agents including K. marina strains in the solution of epoprostenol (pH 10.4) (Flolan(®), GlaxoSmithKline, Ltd., Tokyo, Japan.). To the best of our knowledge, the first description of the property of being tolerant to high alkalinity that the K. marina isolate exhibited was noteworthy and a useful piece of information. In conclusion, we believe that the present study should be a notification regarding the potential risk of catheter-related blood-stream infections due to K. marina, suggestive of an alkalophile, especially in patients receiving continuous intravenous epoprostenol dosing therapy.
Asunto(s)
Epoprostenol/farmacología , Infecciones por Bacterias Grampositivas/microbiología , Micrococcaceae/efectos de los fármacos , Micrococcaceae/fisiología , Inhibidores de Agregación Plaquetaria/farmacología , Bacteriemia/microbiología , Infecciones Relacionadas con Catéteres/microbiología , Niño , Epoprostenol/administración & dosificación , Humanos , Concentración de Iones de Hidrógeno , Masculino , Pruebas de Sensibilidad Microbiana , Micrococcaceae/aislamiento & purificación , Inhibidores de Agregación Plaquetaria/administración & dosificación , Tolerancia a la Sal , Estrés FisiológicoRESUMEN
No abstract available.
Asunto(s)
Adolescente , Adulto , Anciano , Anciano de 80 o más Años , Femenino , Humanos , Recién Nacido , Masculino , Persona de Mediana Edad , Antibacterianos/farmacología , Ceftriaxona/farmacología , Ecocardiografía , Endocarditis Bacteriana/diagnóstico , Inmunosupresores/uso terapéutico , Pruebas de Sensibilidad Microbiana , Micrococcaceae/efectos de los fármacos , ARN Ribosómico 16S/química , República de CoreaRESUMEN
In this study, two halophilic bacterial strains isolated from saline habitats in Argentina grew in the presence of gas oil. They were identified as Halomonas spp. and Nesterenkonia sp. by 16S ribosomal RNA sequencing. Chemotaxis towards gas oil was observed in Halomonas spp. by using swimming assays.
Asunto(s)
Quimiotaxis/efectos de los fármacos , Halomonas/efectos de los fármacos , Micrococcaceae/efectos de los fármacos , Petróleo , Argentina , Biodegradación Ambiental , Halomonas/crecimiento & desarrollo , Halomonas/aislamiento & purificación , Hidrocarburos , Micrococcaceae/crecimiento & desarrollo , Micrococcaceae/aislamiento & purificación , Ribotipificación , Tolerancia a la Sal , Agua de Mar/microbiología , Especificidad de la Especie , Microbiología del Agua , Contaminantes Químicos del AguaRESUMEN
In this study, two halophilic bacterial strains isolated from saline habitats in Argentina grew in the presence of gas oil. They were identified as Halomonas spp. and Nesterenkonia sp. by 16S ribosomal RNA sequencing. Chemotaxis towards gas oil was observed in Halomonas spp. by using swimming assays.
En el presente trabajo se aislaron dos cepas bacterianas halofílicas a partir de muestras obtenidas en ambientes salinos de Argentina, que crecieron en presencia de gasoil como única fuente de carbono. Las cepas aisladas se identificaron como Halomonas spp. y Nesterenkonia sp. mediante secuenciación del gen del ARN ribosomal 16S. En ensayos de swimming, las cepas del genero Halomonas spp. mostraron una respuesta quimiotáctica hacia el gas oil.
Asunto(s)
Quimiotaxis/efectos de los fármacos , Halomonas/efectos de los fármacos , Micrococcaceae/efectos de los fármacos , Petróleo , Argentina , Biodegradación Ambiental , Hidrocarburos , Halomonas/crecimiento & desarrollo , Halomonas/aislamiento & purificación , Micrococcaceae/crecimiento & desarrollo , Micrococcaceae/aislamiento & purificación , Ribotipificación , Tolerancia a la Sal , Especificidad de la Especie , Agua de Mar/microbiología , Microbiología del Agua , Contaminantes Químicos del AguaRESUMEN
Antibiotic residues in milk can cause serious problems for consumers and the dairy industry. Heat treatment of milk may diminish the antimicrobial activity of these antibiotic residues. This study analyzed the effect of milk processing (60 °C for 30 min, 120 °C for 20 min, and 140 °C for 10 s) on the antimicrobial activity of milk samples fortified with three concentrations of three macrolides (erythromycin: 20, 40 and 80 µg/liter; spiramycin: 100, 200, and 400 µg/liter; and tylosin: 500, 1,000, and 2,000 µg/liter) and one lincosamide (lincomycin: 1,000, 2,000, and 4,000 µg/liter). To measure the loss of antimicrobial activity, a bioassay based on the growth inhibition of Micrococcus luteus was done. The data were analyzed using a multiple linear regression model. The results indicate that treatment at 120 °C for 20 min produces inactivation percentages of 93% (erythromycin), 64% (spiramycin), 51% (tylosin), and 5% (lincomycin), while treatment at 140 °C for 10 s results in generally lower percentages (30% erythromycin, 35% spiramycin, 12% tylosin, and 5% lincomycin). The lowest loss or lowest reduction of antimicrobial activity (21% erythromycin and 13% spiramycin) was obtained by treatment at 60 °C for 30 min.
Asunto(s)
Antibacterianos/farmacología , Manipulación de Alimentos/métodos , Calor , Lincosamidas/farmacología , Macrólidos/farmacología , Micrococcaceae/efectos de los fármacos , Leche/química , Animales , Antibacterianos/análisis , Recuento de Colonia Microbiana , Seguridad de Productos para el Consumidor , Relación Dosis-Respuesta a Droga , Residuos de Medicamentos/análisis , Residuos de Medicamentos/farmacología , Humanos , Lincosamidas/análisis , Macrólidos/análisis , Pruebas de Sensibilidad Microbiana , Salud Pública , Factores de TiempoAsunto(s)
Infecciones por Actinomycetales/veterinaria , Caimanes y Cocodrilos , Sulfato de Cobre/uso terapéutico , Micrococcaceae/efectos de los fármacos , Enfermedades Cutáneas Bacterianas/veterinaria , Infecciones por Actinomycetales/tratamiento farmacológico , Infecciones por Actinomycetales/patología , Animales , Sulfato de Cobre/administración & dosificación , Sulfato de Cobre/farmacología , Formaldehído/administración & dosificación , Formaldehído/farmacología , Formaldehído/uso terapéutico , Inmersión , Pruebas de Sensibilidad Microbiana , Enfermedades Cutáneas Bacterianas/tratamiento farmacológico , Enfermedades Cutáneas Bacterianas/patología , Cloruro de Sodio/administración & dosificación , Cloruro de Sodio/farmacología , Cloruro de Sodio/uso terapéutico , Resultado del TratamientoRESUMEN
BACKGROUND: Literature reports indicate that phospholipid liposomes facilitate the accumulation of active agents in the infundibulum. OBJECTIVE: The study hypothesis of an improved antibacterial efficacy of benzoyl peroxide (BPO) in phospholipid liposomes was tested in comparison with a commercial and a pharmacopoeial BPO preparation. METHODS: The infundibular bacterial samples were obtained with the Permabond technique from 20 acne patients who had been treated with the test substances (vehicle-controlled) for 2 weeks twice per day in a single-blinded, comparative study on the upper back. RESULTS: A significant antibacterial effect in the infundibula (Propionibacteria and Micrococcaceae, both: p < 0.001) for a BPO phospholipid liposome formulation could be demonstrated. In comparison to the other significantly efficacious BPO formulations which were also tested (commercial product and pharmacopoeial formulation), the BPO phospholipid liposome formulation showed a significantly greater antibacterial efficacy for Propionibacteria and Micrococcaceae (both: p < 0.01). CONCLUSION: A BPO formulation in phospholipid liposomes may represent an improvement of the conventional external BPO treatment of acne.