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1.
Mar Drugs ; 19(4)2021 Apr 20.
Artículo en Inglés | MEDLINE | ID: mdl-33924262

RESUMEN

Epicotripeptin (1), a new cyclic tripeptide along with four known cyclic dipeptides (2-5) and one acetamide derivative (6) were isolated from seagrass-associated endophytic fungus Epicoccum nigrum M13 recovered from the Red Sea. Additionally, two new compounds, cyclodidepsipeptide phragamide A (7) and trioxobutanamide derivative phragamide B (8), together with eight known compounds (9-16), were isolated from plant-derived endophyte Alternaria alternata 13A collected from a saline lake of Wadi El Natrun depression in the Sahara Desert. The structures of the isolated compounds were determined based on the 1D and 2D NMR spectroscopic data, HRESIMS data, and a comparison with the reported literature. The absolute configurations of 1 and 7 were established by advanced Marfey's and Mosher's ester analyses. The antimicrobial screening indicated that seven of the tested compounds exhibited considerable (MIC range of 2.5-5 µg/mL) to moderate (10-20 µg/mL) antibacterial effect against the tested Gram-positive strains and moderate to weak (10-30 µg/mL) antibacterial effect against Gram-negative strains. Most of the compounds exhibited weak or no activity against the tested Gram-negative strains. On the other hand, four of the tested compounds showed considerable antibiofilm effects against biofilm forming Gram-positive and Gram-negative strains.


Asunto(s)
Alternaria/metabolismo , Antibacterianos/farmacología , Ascomicetos/metabolismo , Biopelículas/efectos de los fármacos , Bacterias Aerobias Gramnegativas/efectos de los fármacos , Bacterias Grampositivas/efectos de los fármacos , Antibacterianos/aislamiento & purificación , Biopelículas/crecimiento & desarrollo , Fermentación , Bacterias Aerobias Gramnegativas/crecimiento & desarrollo , Bacterias Grampositivas/crecimiento & desarrollo , Pruebas de Sensibilidad Microbiana , Estructura Molecular , Relación Estructura-Actividad
2.
Diagn Microbiol Infect Dis ; 98(1): 115100, 2020 Sep.
Artículo en Inglés | MEDLINE | ID: mdl-32622288

RESUMEN

We evaluated the Copan Eswab transport system for the quantitative recovery of Escherichia coli, Klebsiella pneumoniae, and Pseudomonas aeruginosa after 1, 2, 3, 5, and 7 days of storage at room and refrigerator temperatures, and 7 and 30 days of storage at -80 °C and -20 °C using mono- and polymicrobial samples. The study was based on Clinical and Laboratory Standards Institute (CLSI) M40-A2 standard procedures on the quality control of microbiological transport systems. Eswab met the CLSI standards at room and refrigerator temperatures for all (combinations of) bacterial strains tested. At room temperature, after 24 h, bacterial growth was observed. At -80 °C, bacterial viability was maintained in monomicrobial samples; however, in polymicrobial samples, P. aeruginosa recovery was compromised. Storage at -20 °C was unsuitable. We conclude that specimens collected using Eswab should be transported to the laboratory as soon as possible. If transport or processing is delayed, specimens should preferably be stored at refrigerator temperatures.


Asunto(s)
Técnicas Bacteriológicas/métodos , Bacterias Aerobias Gramnegativas/crecimiento & desarrollo , Manejo de Especímenes/métodos , Recuento de Colonia Microbiana , Medios de Cultivo , Escherichia coli/crecimiento & desarrollo , Heces/microbiología , Humanos , Klebsiella pneumoniae/crecimiento & desarrollo , Viabilidad Microbiana , Pseudomonas aeruginosa/crecimiento & desarrollo , Refrigeración , Temperatura , Factores de Tiempo
3.
Microb Ecol ; 76(3): 584-587, 2018 Oct.
Artículo en Inglés | MEDLINE | ID: mdl-29492594

RESUMEN

Achromatium is the largest freshwater bacterium known to date and easily recognised by conspicuous calcite bodies filling the cell volume. Members of this genus are highly abundant in diverse aquatic sediments and may account for up to 90% of the bacterial biovolume in the oxic-anoxic interfaces. The high abundance implies that Achromatium is either rapidly growing or hardly prone to predation. As Achromatium is still uncultivated and does not appear to grow fast, one could assume that the cells might escape predation by their unusual shape and composition. However, we observed various members of the meiofauna grazing or parasitizing on Achromatium. By microphotography, we documented amoebae, ciliates, oligochetes and plathelminthes having Achromatium cells ingested. Some Achromatium cells harboured structures resembling sporangia of parasitic fungi (chytrids) that could be stained with the chitin-specific dye Calcofluor White. Many Achromatia carried prokaryotic epibionts in the slime layer surrounding the cells. Their regular distribution over the cell might indicate that they are commensalistic rather than harming their hosts. In conclusion, we report on various interactions of Achromatium with the sediment community and show that although Achromatium cells are a crispy diet, full of calcite bodies, predators do not spare them.


Asunto(s)
Sedimentos Geológicos/microbiología , Bacterias Aerobias Gramnegativas/crecimiento & desarrollo , Lagos/microbiología , Amoeba/fisiología , Animales , Cilióforos/fisiología , Sedimentos Geológicos/parasitología , Bacterias Aerobias Gramnegativas/clasificación , Bacterias Aerobias Gramnegativas/genética , Bacterias Aerobias Gramnegativas/aislamiento & purificación , Lagos/parasitología , Oligoquetos/fisiología
4.
J Appl Microbiol ; 124(2): 408-422, 2018 Feb.
Artículo en Inglés | MEDLINE | ID: mdl-29178633

RESUMEN

AIMS: To enhance the antimicrobial and antibiofilm activity of norfloxacin against the planktonic and biofilm mode of growth in ESKAPE pathogens using chemically modified norfloxacin salts. METHODS AND RESULTS: Antimicrobial testing, synergy testing and time-kill curve analysis were performed to evaluate antibacterial effect of norfloxacin carboxylic acid salts against ESKAPE pathogens. In vivo efficacy to reduce bacterial bioburden was evaluated in zebrafish infection model. Crystal violet assay and live-dead staining were performed to discern antibiofilm effect. Membrane permeability, integrity and molecular docking studies were carried out to ascertain the mechanism of action. The carboxylic acid salts, relative to parent molecule norfloxacin, displayed two- to fourfold reduction in minimum inhibitory concentration against Staphylococcus aureus and Pseudomonas aeruginosa, in addition to displaying potent bacteriostatic effect against certain members of ESKAPE pathogens. In vivo treatments revealed that norfloxacin tartrate (SRIN2) reduced MRSA bioburden by greater than 1 log fold relative to parent molecule in the muscle tissue. In silico docking with gyrA of S. aureus showed increased affinity of SRIN2 towards DNA gyrase. The enhanced antibacterial effect of norfloxacin salts could be partially accounted by altered membrane permeability in S. aureus and perturbed membrane integrity in P. aeruginosa. Antibiofilm studies revealed that SRIN2 (norfloxacin tartrate) and SRIN3 (norfloxacin benzoate) exerted potent antibiofilm effect particularly against Gram-negative ESKAPE pathogens. The impaired colonization of both S. aureus and P. aeruginosa due to improved norfloxacin salts was further supported by live-dead imaging. CONCLUSION: Norfloxacin carboxylic acid salts can act as potential alternatives in terms of drug resensitization and reuse. SIGNIFICANCE AND IMPACT OF THE STUDY: Our study shows that carboxylic acid salts of norfloxacin could be effectively employed to treat both planktonic- and biofilm-based infections caused by select members of ESKAPE pathogens.


Asunto(s)
Antibacterianos/farmacología , Biopelículas/efectos de los fármacos , Bacterias Aerobias Gramnegativas/efectos de los fármacos , Infecciones por Bacterias Gramnegativas/microbiología , Norfloxacino/farmacología , Staphylococcus aureus/efectos de los fármacos , Acinetobacter baumannii/efectos de los fármacos , Acinetobacter baumannii/crecimiento & desarrollo , Acinetobacter baumannii/fisiología , Animales , Antibacterianos/química , Ácidos Carboxílicos/química , Ácidos Carboxílicos/farmacología , Enterobacter/efectos de los fármacos , Enterobacter/crecimiento & desarrollo , Enterobacter/fisiología , Enterococcus faecium/efectos de los fármacos , Enterococcus faecium/crecimiento & desarrollo , Enterococcus faecium/fisiología , Escherichia coli/efectos de los fármacos , Escherichia coli/crecimiento & desarrollo , Escherichia coli/fisiología , Bacterias Aerobias Gramnegativas/crecimiento & desarrollo , Bacterias Aerobias Gramnegativas/fisiología , Klebsiella pneumoniae/efectos de los fármacos , Klebsiella pneumoniae/crecimiento & desarrollo , Klebsiella pneumoniae/fisiología , Pruebas de Sensibilidad Microbiana , Norfloxacino/química , Pseudomonas aeruginosa/efectos de los fármacos , Pseudomonas aeruginosa/crecimiento & desarrollo , Pseudomonas aeruginosa/fisiología , Infecciones Estafilocócicas/microbiología , Staphylococcus aureus/crecimiento & desarrollo , Staphylococcus aureus/fisiología
5.
Nutrients ; 9(4)2017 04 03.
Artículo en Inglés | MEDLINE | ID: mdl-28368356

RESUMEN

Green cincau (Premna oblongifolia Merr) is an Indonesian food plant with a high dietary fibre content. Research has shown that dietary fibre mixtures may be more beneficial for colorectal cancer prevention than a single dietary fibre type. The aim of this study was to investigate the effects of green cincau extract on short chain fatty acid (SCFA) production in anaerobic batch cultures inoculated with human faecal slurries and to compare these to results obtained using different dietary fibre types (pectin, inulin, and cellulose), singly and in combination. Furthermore, fermentation supernatants (FSs) were evaluated in Caco-2 cells for their effect on cell viability, differentiation, and apoptosis. Cincau increased total SCFA concentration by increasing acetate and propionate, but not butyrate concentration. FSs from all dietary fibre sources, including cincau, reduced Caco-2 cell viability. However, the effects of all FSs on cell viability, cell differentiation, and apoptosis were not simply explainable by their butyrate content. In conclusion, products of fermentation of cincau extracts induced cell death, but further work is required to understand the mechanism of action. This study demonstrates for the first time that this Indonesian traditional source of dietary fibre may be protective against colorectal cancer.


Asunto(s)
Anticarcinógenos/metabolismo , Apoptosis , Neoplasias del Colon/prevención & control , Fibras de la Dieta/metabolismo , Microbioma Gastrointestinal , Extractos Vegetales/metabolismo , Prebióticos , Anticarcinógenos/aislamiento & purificación , Células CACO-2 , Diferenciación Celular , Supervivencia Celular , Celulosa/metabolismo , Neoplasias del Colon/metabolismo , Neoplasias del Colon/microbiología , Neoplasias del Colon/patología , Ácidos Grasos Volátiles/metabolismo , Heces/microbiología , Fermentación , Bacterias Aerobias Gramnegativas/crecimiento & desarrollo , Bacterias Aerobias Gramnegativas/aislamiento & purificación , Bacterias Aerobias Gramnegativas/metabolismo , Bacterias Grampositivas/crecimiento & desarrollo , Bacterias Grampositivas/aislamiento & purificación , Bacterias Grampositivas/metabolismo , Humanos , Indonesia , Inulina/metabolismo , Lamiaceae/química , Pectinas/metabolismo , Extractos Vegetales/química , Extractos Vegetales/aislamiento & purificación , Hojas de la Planta/química , Prebióticos/análisis
6.
J Sci Food Agric ; 97(3): 929-938, 2017 Feb.
Artículo en Inglés | MEDLINE | ID: mdl-27220662

RESUMEN

BACKGROUND: The objective of the present work was to develop strategies for increasing the shelf-life of red raspberries (Rubus idaeus L.), by preventing microorganism growth. RESULTS: Fruits coated with alginate plus lemon essential oil (0.2%) or orange essential oil (0.1%) after 15 days of storage had less red skin than the remaining samples. The less red color verified in these samples was also coincident with the lower concentration of anthocyanins at the end of the experiment as well as the lower capacity for scavenging ABTS free radicals or quenching singlet oxygen. Cyanidin and pelargonidin glucosides were found in raspberries fruits. The edible coatings supplemented with the essential oil of orange either at 0.1% or 0.2% were very efficient for controlling yeast and mold growth after 15 days of storage. To control the development of aerobic mesophilic bacteria the use of essential oil of lemon 0.2% and essential oil of orange 0.1% were the most efficient. CONCLUSION: The application of the film improved post-harvest quality of raspberry, since the addition of essential oils of citrus films promoted to the inhibitory effect of fungi and bacteria growth after 15 days of storage, without changing quality parameters. © 2016 Society of Chemical Industry.


Asunto(s)
Citrus/química , Conservantes de Alimentos/química , Calidad de los Alimentos , Almacenamiento de Alimentos , Frutas/química , Aceites Volátiles/química , Rubus/química , Alginatos/química , Antocianinas/análisis , Antocianinas/química , Antibacterianos/efectos adversos , Antibacterianos/química , Antibacterianos/metabolismo , Brasil , Conservantes de Alimentos/efectos adversos , Conservantes de Alimentos/metabolismo , Depuradores de Radicales Libres/análisis , Depuradores de Radicales Libres/química , Frutas/microbiología , Hongos/crecimiento & desarrollo , Hongos/aislamiento & purificación , Fungicidas Industriales/efectos adversos , Fungicidas Industriales/química , Fungicidas Industriales/metabolismo , Ácido Glucurónico/química , Bacterias Aerobias Gramnegativas/crecimiento & desarrollo , Bacterias Aerobias Gramnegativas/aislamiento & purificación , Bacterias Grampositivas/crecimiento & desarrollo , Bacterias Grampositivas/aislamiento & purificación , Ácidos Hexurónicos/química , Humanos , Valor Nutritivo , Aceites Volátiles/efectos adversos , Aceites Volátiles/metabolismo , Pigmentos Biológicos/análisis , Pigmentos Biológicos/química , Análisis de Componente Principal , Rubus/microbiología , Propiedades de Superficie , Levaduras/crecimiento & desarrollo , Levaduras/aislamiento & purificación
7.
Foodborne Pathog Dis ; 13(12): 656-660, 2016 12.
Artículo en Inglés | MEDLINE | ID: mdl-27992273

RESUMEN

Organic foods have risen in popularity recently. However, the increased risk of bacterial contamination of organic foods has not been fully evaluated. In this study, 100 samples each of organic and conventional fresh vegetables (55 lettuce samples and 45 sprout samples) sold in South Korea were analyzed for aerobic bacteria, coliforms, Escherichia coli, and Bacillus cereus. Although the aerobic bacteria and coliform counts were not significantly different between the two farming types (p > 0.05), the occurrence rate of B. cereus was higher in organically cultivated vegetables compared with those grown conventionally (70% vs. 30%, respectively). The mean contamination level of B. cereus-positive organic samples was also significantly higher (1.86 log colony-forming unit [CFU]/g vs. 0.69 log CFU/g, respectively) (p < 0.05). In addition, six samples of organic vegetables were found to be contaminated with B. cereus at over 4 log CFU/g categorized as unsatisfactory according to Health Protection Agency guideline. The relatively higher occurrence rate of B. cereus in organic vegetables emphasizes the importance of implementing control measures in organic vegetable production and postharvest processing to reduce the risk of food poisoning.


Asunto(s)
Bacillus cereus/aislamiento & purificación , Contaminación de Alimentos , Calidad de los Alimentos , Alimentos Orgánicos/microbiología , Verduras/microbiología , Bacillus cereus/crecimiento & desarrollo , Recuento de Colonia Microbiana , Enterobacteriaceae/crecimiento & desarrollo , Enterobacteriaceae/aislamiento & purificación , Escherichia coli/crecimiento & desarrollo , Escherichia coli/aislamiento & purificación , Inspección de Alimentos , Conservación de Alimentos , Alimentos Orgánicos/efectos adversos , Alimentos Orgánicos/economía , Alimentos Orgánicos/normas , Enfermedades Transmitidas por los Alimentos/epidemiología , Enfermedades Transmitidas por los Alimentos/etiología , Enfermedades Transmitidas por los Alimentos/microbiología , Enfermedades Transmitidas por los Alimentos/prevención & control , Bacterias Aerobias Gramnegativas/crecimiento & desarrollo , Bacterias Aerobias Gramnegativas/aislamiento & purificación , Bacterias Grampositivas/crecimiento & desarrollo , Bacterias Grampositivas/aislamiento & purificación , Guías como Asunto , Humanos , Lactuca/economía , Lactuca/crecimiento & desarrollo , Lactuca/microbiología , Lactuca/normas , Hojas de la Planta/efectos adversos , Hojas de la Planta/crecimiento & desarrollo , Hojas de la Planta/microbiología , Práctica de Salud Pública , Control de Calidad , República de Corea/epidemiología , Riesgo , Plantones/efectos adversos , Plantones/crecimiento & desarrollo , Plantones/microbiología , Verduras/economía , Verduras/crecimiento & desarrollo , Verduras/normas
8.
J Sci Food Agric ; 96(13): 4514-22, 2016 Oct.
Artículo en Inglés | MEDLINE | ID: mdl-26869338

RESUMEN

BACKGROUND: Chestnut is a relatively new cultivated crop for Michigan, and postharvest loss due to decay has been problematic as production has increased each year. In 2007, more than 25% of chestnuts were lost to postharvest decay, equivalent to approximately 5300 kg of fresh product. To determine the organisms responsible for decay, a microbiological survey was performed in 2006 and 2007 to identify microorganisms involved in postharvest shell (external surface) mold and internal kernel (edible portion) decay of chestnuts. RESULTS: Filamentous fungi including Penicillium expansum, Penicillium griseofulvum, Penicillium chrysogenum, Coniophora puteana, Acrospeira mirabilis, Botryosphaeria ribis, Sclerotinia sclerotiorum, Botryotinia fuckeliana (anamorph Botrytis cinerea) and Gibberella sp. (anamorph Fusarium sp.) were the predominant microorganisms that negatively impacted fresh chestnuts. Populations of microorganisms varied between farms, harvesting methods and chestnut parts. CONCLUSION: Chestnuts harvested from the orchard floor were significantly (P < 0.05) more contaminated than chestnuts harvested directly from the tree, by more than 2 log colony-forming units (CFU) g(-1) . In addition, a significant difference (P < 0.05) in the microbial population was seen between chestnuts submitted by different growers, with average count ranges of fungi, mesophilic aerobic bacteria (MAB) and yeasts equal to 4.75, 4.59 and 4.75 log CFU g(-1) respectively. © 2016 Society of Chemical Industry.


Asunto(s)
Producción de Cultivos , Productos Agrícolas/microbiología , Fagaceae/microbiología , Inspección de Alimentos , Almacenamiento de Alimentos , Hongos/crecimiento & desarrollo , Nueces/microbiología , Ascomicetos/clasificación , Ascomicetos/crecimiento & desarrollo , Ascomicetos/aislamiento & purificación , Basidiomycota/clasificación , Basidiomycota/crecimiento & desarrollo , Basidiomycota/aislamiento & purificación , Botrytis/clasificación , Botrytis/crecimiento & desarrollo , Botrytis/aislamiento & purificación , Productos Agrícolas/crecimiento & desarrollo , Cruzamientos Genéticos , Fagaceae/crecimiento & desarrollo , Hongos/clasificación , Hongos/aislamiento & purificación , Bacterias Aerobias Gramnegativas/clasificación , Bacterias Aerobias Gramnegativas/crecimiento & desarrollo , Bacterias Aerobias Gramnegativas/aislamiento & purificación , Bacterias Grampositivas/clasificación , Bacterias Grampositivas/crecimiento & desarrollo , Bacterias Grampositivas/aislamiento & purificación , Michigan , Tipificación Molecular , Técnicas de Tipificación Micológica , Nueces/crecimiento & desarrollo , Penicillium/clasificación , Penicillium/crecimiento & desarrollo , Penicillium/aislamiento & purificación , Phaeophyceae/clasificación , Phaeophyceae/crecimiento & desarrollo , Phaeophyceae/aislamiento & purificación , Microbiología del Suelo , Análisis Espacio-Temporal , Propiedades de Superficie , Levaduras/clasificación , Levaduras/crecimiento & desarrollo , Levaduras/aislamiento & purificación
9.
Meat Sci ; 111: 53-9, 2016 Jan.
Artículo en Inglés | MEDLINE | ID: mdl-26340741

RESUMEN

The microbial contamination of animal carcasses with respect to the limits established by Regulation (EC) No. 2073/2005 was investigated. Bovine, ovine, and swine carcasses (n=536 samples) from three small-scale abattoirs were sampled using abrasive sponges and tested for aerobic colony counts (ACC) and Enterobacteriaceae in the period 2010-2013. Mean ACC values reached 1.96 log cfu/cm(2) on bovine carcasses and 2.27 log cfu/cm(2) on both swine and ovine carcasses; Enterobacteriaceae counts of 0.01, 0.20 and 0.27 log cfu/cm(2) were found for bovine, swine and ovine carcasses, respectively. Abattoir 1 showed the highest values of ACC; no differences among abattoirs were highlighted for Enterobacteriaceae. Compared with swine and ovine carcasses, bovine carcasses showed significantly lower means for both ACC and Enterobacteriaceae. The data collected indicated that the management of the three abattoirs met high quality standards, thereby proving that it is feasible to achieve good microbiological quality in abattoirs when adequate Good Hygiene Practices are applied.


Asunto(s)
Enterobacteriaceae/aislamiento & purificación , Contaminación de Alimentos , Manipulación de Alimentos , Inspección de Alimentos , Bacterias Aerobias Gramnegativas/aislamiento & purificación , Industria para Empaquetado de Carne/métodos , Carne/microbiología , Mataderos , Animales , Bovinos , Recuento de Colonia Microbiana , Enterobacteriaceae/crecimiento & desarrollo , Unión Europea , Contaminación de Alimentos/prevención & control , Manipulación de Alimentos/normas , Bacterias Aerobias Gramnegativas/crecimiento & desarrollo , Guías como Asunto , Análisis de Peligros y Puntos de Control Críticos , Italia , Industria para Empaquetado de Carne/tendencias , Control de Calidad , Oveja Doméstica , Sus scrofa
10.
Mar Drugs ; 13(4): 2526-40, 2015 Apr 22.
Artículo en Inglés | MEDLINE | ID: mdl-25913707

RESUMEN

Eleven new polyphenols namely spiromastols A-K (1-11) were isolated from the fermentation broth of a deep sea-derived fungus Spiromastix sp. MCCC 3A00308. Their structures were determined by extensive NMR data and mass spectroscopic analysis in association with chemical conversion. The structures are classified as diphenyl ethers, diphenyl esters and isocoumarin derivatives, while the n-propyl group in the analogues is rarely found in natural products. Compounds 1-3 exhibited potent inhibitory effects against a panel of bacterial strains, including Xanthomanes vesicatoria, Pseudomonas lachrymans, Agrobacterium tumefaciens, Ralstonia solanacearum, Bacillus thuringensis, Staphylococcus aureus and Bacillus subtilis, with minimal inhibitory concentration (MIC) values ranging from 0.25 to 4 µg/mL. The structure-activity relationships are discussed, while the polychlorinated analogues 1-3 are assumed to be a promising structural model for further development as antibacterial agents.


Asunto(s)
Antibacterianos/aislamiento & purificación , Organismos Acuáticos/química , Ascomicetos/química , Clorofenoles/aislamiento & purificación , Descubrimiento de Drogas , Éteres Difenilos Halogenados/aislamiento & purificación , Éteres Fenílicos/aislamiento & purificación , Polifenoles/aislamiento & purificación , Altitud , Antibacterianos/química , Antibacterianos/farmacología , Océano Atlántico , Bacillales/efectos de los fármacos , Bacillales/crecimiento & desarrollo , Clorofenoles/química , Clorofenoles/farmacología , Dicroismo Circular , Fermentación , Bacterias Aerobias Gramnegativas/efectos de los fármacos , Bacterias Aerobias Gramnegativas/crecimiento & desarrollo , Éteres Difenilos Halogenados/química , Éteres Difenilos Halogenados/farmacología , Halogenación , Espectroscopía de Resonancia Magnética , Metilación , Pruebas de Sensibilidad Microbiana , Estructura Molecular , Éteres Fenílicos/química , Éteres Fenílicos/farmacología , Polifenoles/química , Polifenoles/farmacología , Microbiología del Suelo , Espectrometría de Masa por Ionización de Electrospray , Relación Estructura-Actividad
11.
Pharm Biol ; 53(9): 1386-90, 2015.
Artículo en Inglés | MEDLINE | ID: mdl-25874387

RESUMEN

CONTEXT: Amanita ovoidea (Bull.) Link (Amanitaceae) is a well-known species due to its pleasant aroma and flavor since ancient times in the worldwide. This species is also known in Turkey and people consume it extensively. OBJECTIVE: To evaluate medicinal importance of A. ovoidea for human health, to explain the effect of mushroom extracts on bacterial DNA, and to find preventive role on bacterial disease. MATERIALS AND METHODS: Chloroform, acetone, and methanol extracts of A. ovoidea were tested for the antimicrobial activities against four Gram-positive bacteria, five Gram-negative bacteria, and yeast using a micro-dilution method. In addition, DNA binding, DNA cleavage activity, and restriction enzyme digestion of the methanol extract of A. ovoidea were examined at different concentrations (40.000-78.125 µg/mL). RESULTS: The highest minimum inhibitory concentration (MIC) value observed against the test micro-organisms was with the chloroform extract (MIC 19.5 µg/mL concentration) against Candida albicans. Other highest antimicrobial effects observed against the test micro-organisms were with the methanol extracts against Bacillus subtilis, Staphylococcus aureus, Listeria monocytogenes, Streptococcus pyogenes, Candida albicans, Klebsiella pneumoniae, Proteus vulgaris, and Salmonella enteritidis (MICs, 78 µg/mL concentrations). All concentrations reduced the mobility of plasmid DNA. BamHI and HindIII targeted specially to supercoils and cut them. Amanita ovoidea extract prevented cutting with HindIII by binding especially to the AA region in open circular DNA. DISCUSSION AND CONCLUSION: Present results demonstrated that A. ovoidea has excellent antimicrobial and antifungal activities by its DNA interaction activity on pBR322.


Asunto(s)
Amanita , Antibacterianos/farmacología , Antifúngicos/farmacología , Candida albicans/efectos de los fármacos , Bacterias Aerobias Gramnegativas/efectos de los fármacos , Bacterias Grampositivas/efectos de los fármacos , Plásmidos/efectos de los fármacos , Acetona/química , Amanita/química , Antibacterianos/aislamiento & purificación , Antifúngicos/aislamiento & purificación , Candida albicans/crecimiento & desarrollo , Cloroformo/química , Bacterias Aerobias Gramnegativas/crecimiento & desarrollo , Bacterias Grampositivas/crecimiento & desarrollo , Metanol/química , Pruebas de Sensibilidad Microbiana , Fitoterapia , Solventes/química
12.
Pharm Biol ; 53(9): 1339-43, 2015.
Artículo en Inglés | MEDLINE | ID: mdl-25864864

RESUMEN

CONTEXT: Brazilin is a major active principle of Caesalpinia sappan L. (Leguminosae or Fabaceae). For industry aspects, brazilin-rich extract (BRE) has been prepared and standardized to contain 39% w/w brazilin. BRE may have more advantages than brazilin in term of a lower-cost production process. OBJECTIVES: To investigate the antioxidant, antibacterial, and anti-inflammatory activities of BRE. MATERIAL AND METHODS: BRE was prepared by a simple one-step purification of the crude ethanol extract of C. sappan heartwood (CSE) using a Diaion® HP-20 column. The antioxidant activities were determined using three methods, including DPPH radical scavenging, reducing power, and ß-carotene bleaching assays, at concentration ranges of 1-10, 10-100, and 10-100 µg/mL, respectively. Minimum inhibitory concentration (MIC) and minimum bactericidal concentration (MBC) of BRE (15.6-1000 µg/mL) against Gram-positive and Gram-negative bacteria were determined by the broth microdilution method. Anti-inflammatory activity of BRE (0.1-5 µg/mL) was evaluated as anti-denaturation activity using bovine serum albumin as a substrate. RESULTS AND DISCUSSION: On the basis of ß-carotene bleaching assay, BRE showed antioxidant activity with an EC50 value of 60.5 µg/mL, which was almost equal to that of pure brazilin (52.1 µg/mL). Gram-positive bacteria were more sensitive to all tested samples than Gram-negative bacteria. BRE possessed higher antibacterial activities than CSE, but lower than brazilin. MIC/MBC values of 62.5-125/125 and 250-500/250-500 µg/mL were obtained for BRE against Gram-positive and Gram-negative bacteria, respectively. A low concentration (0.1 µg/mL) of brazilin, BRE, and CSE showed anti-inflammatory activity by inhibiting protein denaturation up to 46.8, 54.1, and 61.9%, respectively.


Asunto(s)
Antibacterianos/farmacología , Antiinflamatorios/farmacología , Antioxidantes/farmacología , Benzopiranos/farmacología , Caesalpinia , Extractos Vegetales/farmacología , Antibacterianos/química , Antibacterianos/aislamiento & purificación , Antibacterianos/normas , Antiinflamatorios/química , Antiinflamatorios/aislamiento & purificación , Antiinflamatorios/normas , Antioxidantes/química , Antioxidantes/aislamiento & purificación , Antioxidantes/normas , Benzopiranos/química , Benzopiranos/aislamiento & purificación , Benzopiranos/normas , Compuestos de Bifenilo/química , Caesalpinia/química , Relación Dosis-Respuesta a Droga , Etanol/química , Bacterias Aerobias Gramnegativas/efectos de los fármacos , Bacterias Aerobias Gramnegativas/crecimiento & desarrollo , Bacterias Grampositivas/efectos de los fármacos , Bacterias Grampositivas/crecimiento & desarrollo , Pruebas de Sensibilidad Microbiana , Oxidación-Reducción , Fitoterapia , Picratos/química , Extractos Vegetales/química , Extractos Vegetales/aislamiento & purificación , Extractos Vegetales/normas , Plantas Medicinales , Desnaturalización Proteica , Albúmina Sérica Bovina/química , Solventes/química , beta Caroteno/química
13.
Meat Sci ; 106: 1-5, 2015 Aug.
Artículo en Inglés | MEDLINE | ID: mdl-25839997

RESUMEN

Microbiological contamination in dry-cured ham can occur in the early stages of the process, a large number of microorganisms involved in spoilage can produce alterations in the product. These include non-common odours, which are detected at the end of the process by a procedure called "cala", consisting of a sharp instrument punctured in every ham; this is smelled by an expert taster, who classifies hams as good and altered hams. An electronic device would be suitable for this process given the large amount of hams. The present research aims to develop objective equipment based on the potentiometry technique that identifies altered hams. A probe was developed, containing silver, nickel and copper electrodes, and was employed to classify altered and unaltered hams prior to classification by a tester. The results shown lower Ag and higher Cu potential values for altered hams. The differences in potentiometric response reveal a classification model, although further studies are required to obtain a reliable classification model.


Asunto(s)
Inspección de Alimentos/instrumentación , Calidad de los Alimentos , Alimentos en Conserva/análisis , Carne/análisis , Animales , Fenómenos Químicos , Alimentos en Conserva/microbiología , Bacterias Aerobias Gramnegativas/crecimiento & desarrollo , Bacterias Aerobias Gramnegativas/aislamiento & purificación , Carne/microbiología , Viabilidad Microbiana , Micrococcaceae/crecimiento & desarrollo , Micrococcaceae/aislamiento & purificación , Potenciometría/instrumentación , Análisis de Componente Principal , España , Sus scrofa , Muslo
14.
J Chemother ; 27(2): 67-73, 2015 Feb.
Artículo en Inglés | MEDLINE | ID: mdl-24548089

RESUMEN

The study for monitoring antimicrobial resistance trends (SMART) surveillance program monitors the epidemiology and trends in antibiotic resistance of intra-abdominal pathogens to currently used therapies. The current report describes such trends during 2010-2011. A total of 25,746 Gram-negative clinical isolates from intra-abdominal infections were collected and classified as hospital-associated (HA) if the hospital length of stay (LOS) at the time of specimen collection was ≥48 hours, community-associated (CA) if LOS at the time of specimen collection was <48 hours, or unknown (no designation given by participating centre). A total of 92 different species were collected of which the most common was Escherichia coli: 39% of all isolates in North America to 55% in Africa. Klebsiella pneumoniae was the second most common pathogen: 11% of all isolates from Europe to 19% of all isolates from Asia. Isolates were from multiple intra-abdominal sources of which 32% were peritoneal fluid, 20% were intra-abdominal abscesses, and 16.5% were gall bladder infections. Isolates were further classified as HA (55% of all isolates), CA (39% of all isolates), or unknown (6% of all isolates). The most active antibiotics tested were imipenem, ertapenem, amikacin, and piperacillin-tazobactam. Resistance rates to all other antibiotics tested were high. Considering the current data set and high-level resistance of intra-abdominal pathogens to various antibiotics, further monitoring of the epidemiology of intra-abdominal infections and their susceptibility to antibiotics through SMART is warranted.


Asunto(s)
Antibacterianos/uso terapéutico , Farmacorresistencia Bacteriana , Salud Global , Bacterias Aerobias Gramnegativas/efectos de los fármacos , Infecciones por Bacterias Gramnegativas/tratamiento farmacológico , Infecciones Intraabdominales/tratamiento farmacológico , Absceso Abdominal/tratamiento farmacológico , Absceso Abdominal/epidemiología , Absceso Abdominal/microbiología , Antibacterianos/farmacología , Líquido Ascítico/microbiología , Colecistitis/tratamiento farmacológico , Colecistitis/epidemiología , Colecistitis/microbiología , Infección Hospitalaria/tratamiento farmacológico , Infección Hospitalaria/epidemiología , Infección Hospitalaria/microbiología , Farmacorresistencia Bacteriana Múltiple , Monitoreo Epidemiológico , Escherichia coli/efectos de los fármacos , Escherichia coli/crecimiento & desarrollo , Escherichia coli/aislamiento & purificación , Infecciones por Escherichia coli/tratamiento farmacológico , Infecciones por Escherichia coli/epidemiología , Infecciones por Escherichia coli/microbiología , Bacterias Aerobias Gramnegativas/crecimiento & desarrollo , Bacterias Aerobias Gramnegativas/aislamiento & purificación , Infecciones por Bacterias Gramnegativas/epidemiología , Infecciones por Bacterias Gramnegativas/microbiología , Humanos , Incidencia , Infecciones Intraabdominales/epidemiología , Infecciones Intraabdominales/microbiología , Infecciones por Klebsiella/tratamiento farmacológico , Infecciones por Klebsiella/epidemiología , Infecciones por Klebsiella/microbiología , Klebsiella pneumoniae/efectos de los fármacos , Klebsiella pneumoniae/crecimiento & desarrollo , Klebsiella pneumoniae/aislamiento & purificación , Tiempo de Internación , Pruebas de Sensibilidad Microbiana
15.
J Sci Food Agric ; 95(5): 1016-23, 2015 Mar 30.
Artículo en Inglés | MEDLINE | ID: mdl-24931827

RESUMEN

BACKGROUND: Supercritical carbon dioxide (SC-CO2 ) has been shown to have a good pasteurising effect on food. However, very few research papers have investigated the possibility to exploit this treatment for solid foods, particularly for seafood. Considering the microbial safety of raw seafood consumption, the study aimed to explore the feasibility of microbial inactivation of shrimp (Metapenaeus ensis) and conch (Rapana venosa) by SC-CO2 treatment. RESULTS: Response surface methodology (RSM) models were established to predict and analyse the SC-CO2 process. A 3.69-log reduction in the total aerobic plate count (TPC) of shrimp was observed by SC-CO2 treatment at 53°C, 15 MPa for 40 min, and the logarithmic reduction in TPC of conch was 3.31 at 55°C, 14 MPa for 42 min. Sensory scores of the products achieved approximately 8 (desirable). The optimal parameters for microbial inactivation of shrimp and conch by SC-CO2 might be 55°C, 15 MPa and 40 min. CONCLUSION: SC-CO2 exerted a strong bactericidal effect on the TPC of shrimp and conch, and the products maintained good organoleptic properties. This study verified the feasibility of microbial inactivation of shrimp and conch by SC-CO2 treatment.


Asunto(s)
Dióxido de Carbono/química , Conservación de Alimentos , Gastrópodos/microbiología , Bacterias Aerobias Gramnegativas/crecimiento & desarrollo , Bacterias Grampositivas/crecimiento & desarrollo , Penaeidae/microbiología , Mariscos/microbiología , Animales , China , Recuento de Colonia Microbiana , Estudios de Factibilidad , Conservación de Alimentos/instrumentación , Alimentos Congelados/análisis , Alimentos Congelados/microbiología , Gastrópodos/química , Bacterias Aerobias Gramnegativas/aislamiento & purificación , Bacterias Grampositivas/aislamiento & purificación , Calor , Humanos , Viabilidad Microbiana , Penaeidae/química , Transición de Fase , Presión , Sensación , Mariscos/análisis , Mariscos/economía , Estadística como Asunto , Factores de Tiempo
16.
Br J Nutr ; 112(8): 1296-302, 2014 Oct 28.
Artículo en Inglés | MEDLINE | ID: mdl-25313574

RESUMEN

The present study was conducted to investigate the effects of dietary fructo-oligosaccharide (FOS) (0, 1, 2 and 3%) supplementation on the growth performance, haemato-immunological parameters, cultivable autochthonous (non-adherent) intestinal microbiota and stress resistance of common carp (Cyprinus carpio) fry (3·23 (SEM 0·14) g). These parameters were measured after feeding the carp fry with the experimental diets for 7 weeks. Dietary FOS supplementation had no significant effects on the growth performance and food intake of carp fry compared with the control treatment. It also had no significant effects on the following haematological parameters: erythrocyte count; leucocyte counts (WBC); haematocrit; Hb; mean corpuscular volume; mean corpuscular Hb content; mean corpuscular Hb concentration. However, WBC and respiratory burst activity were significantly affected by dietary FOS supplementation. Evaluation of the cultivable autochthonous intestinal microbiota revealed a significant increase in the levels of total viable heterotrophic aerobic bacteria and lactic acid bacteria in fish fed diets supplemented with 2 and 3% FOS. Furthermore, dietary FOS supplementation significantly increased the survival rate and stress resistance of carp fry compared with the control treatment. These results encourage conducting further research on the administration of FOS and other prebiotics in carp fry studies.


Asunto(s)
Carpas/crecimiento & desarrollo , Dieta/veterinaria , Resistencia a la Enfermedad , Enfermedades de los Peces/prevención & control , Intestinos/microbiología , Oligosacáridos/uso terapéutico , Estrés Fisiológico , Animales , Acuicultura , Adhesión Bacteriana , Carpas/inmunología , Carpas/microbiología , Ingestión de Energía , Enfermedades de los Peces/sangre , Enfermedades de los Peces/etiología , Enfermedades de los Peces/inmunología , Fructosa/análisis , Bacterias Aerobias Gramnegativas/crecimiento & desarrollo , Bacterias Aerobias Gramnegativas/inmunología , Bacterias Aerobias Gramnegativas/aislamiento & purificación , Inmunidad Innata , Irán , Lactobacillales/crecimiento & desarrollo , Lactobacillales/inmunología , Lactobacillales/aislamiento & purificación , Leucocitos/inmunología , Viabilidad Microbiana , Oligosacáridos/administración & dosificación , Oligosacáridos/química , Prebióticos , Análisis de Supervivencia , Aumento de Peso
17.
Acta Pharm ; 64(3): 379-85, 2014 Sep.
Artículo en Inglés | MEDLINE | ID: mdl-25296683

RESUMEN

This study evaluated the effectiveness of the essential oil of Pimenta pseudocaryophyllus in inhibiting the growth of the main bacteria responsible for bad perspiration odor (Staphylococcus epidermidis, Proteus hauseri, Micrococcus yunnanensis and Corynebacterium xerosis). The chemical profile of the essential oil was evaluated by high-resolution gas chromatography (HR-GC) and four constituents were identified, eugenol being the major component (88.6%). The antimicrobial activity was evaluated by means of the turbidimetric method, using the microdilution assay. The minimum inhibitory concentration (MIC) values of the essential oil ranged from 500 to 1,000 µg mL⁻¹. Scanning electron microscope (SEM) observations confirmed the physical damage and morphological alteration of the test bacteria treated with the essential oil, reference drugs and eugenol. The findings of the study demonstrated that this essential oil can be used in the formulation of personal care products.


Asunto(s)
Antiinfecciosos/farmacología , Aceites Volátiles/farmacología , Pimenta , Aceites de Plantas/farmacología , Antiinfecciosos/aislamiento & purificación , Bacterias Aerobias Gramnegativas/efectos de los fármacos , Bacterias Aerobias Gramnegativas/crecimiento & desarrollo , Bacterias Aerobias Gramnegativas/ultraestructura , Bacterias Grampositivas/efectos de los fármacos , Bacterias Grampositivas/crecimiento & desarrollo , Bacterias Grampositivas/ultraestructura , Pruebas de Sensibilidad Microbiana , Microscopía Electrónica de Rastreo , Aceites Volátiles/aislamiento & purificación , Fitoterapia , Pimenta/química , Aceites de Plantas/aislamiento & purificación , Plantas Medicinales
18.
Intensive Care Med ; 38(11): 1738-50, 2012 Nov.
Artículo en Inglés | MEDLINE | ID: mdl-23001446

RESUMEN

PURPOSE: Gut overgrowth is the pathophysiological event in the critically ill requiring intensive care. In relation to the risk of developing a clinically important outcome, gut overgrowth is defined as ≥10(5) potential pathogens including 'abnormal' aerobic Gram-negative bacilli (AGNB), 'normal' bacteria and yeasts, per mL of digestive tract secretion. Surveillance samples of throat and gut are the only samples to detect overgrowth. Gut overgrowth is the crucial event which precedes both primary and secondary endogenous infection, and a risk factor for the development of de novo resistance. Selective decontamination of the digestive tract (SDD) is an antimicrobial prophylaxis designed to control overgrowth. METHODS: There have been 65 randomised controlled trials of SDD in 15,000 patients over 25 years and 11 meta-analyses, which are reviewed. RESULTS AND CONCLUSIONS: These trials demonstrate that the full SDD regimen using parenteral and enteral antimicrobials reduces lower airway infection by 72 %, blood stream infection by 37 %, and mortality by 29 %. Resistance is also controlled. Parenteral cefotaxime which reaches high salivary and biliary concentrations eradicates overgrowth of 'normal' bacteria such as Staphylococcus aureus in the throat. Enteral polyenes control 'normal' Candida species. Enteral polymyxin and tobramycin, eradicate, or prevent gut overgrowth of 'abnormal' AGNB. Enteral vancomycin controls overgrowth of 'abnormal' methicillin-resistant S. aureus. SDD controls overgrowth by achieving high antimicrobial concentrations effective against 'normal' and 'abnormal' potential pathogens rather than by selectivity.


Asunto(s)
Profilaxis Antibiótica , Infecciones Bacterianas/prevención & control , Portador Sano/tratamiento farmacológico , Descontaminación/métodos , Sistema Digestivo/microbiología , Portador Sano/diagnóstico , Enfermedad Crítica , Bacterias Aerobias Gramnegativas/crecimiento & desarrollo , Humanos , Metaanálisis como Asunto , Ensayos Clínicos Controlados Aleatorios como Asunto
19.
Food Sci Technol Int ; 17(5): 471-9, 2011 Oct.
Artículo en Inglés | MEDLINE | ID: mdl-21954309

RESUMEN

The role of different washing solutions and contact times was investigated to determine their use as potential sanitizers for maintaining the microbial quality and food safety of fresh-cut paprika. Samples were cut into small pieces, washed for both 90 and 180 s by different washing solutions: tap water, chlorinated water (100 mg/L and pH 6.5-7), electrolyzed water (pH 7.2) and ozonized water (4 mg/L). Then, samples were packaged in 50 µm polypropylene bags and stored at 5 °C for 12 days, followed by an evaluation of the antimicrobial efficacy of the treatments. Various quality and safety parameters, such as gas composition, color, off-odor, electrical conductivity and microbial numbers, were evaluated during storage. Results revealed insignificant differences in gas composition, and no off-odor was observed in any of the samples during the storage period. However, longer contact time resulted in slightly lower hue angle value than a short one for all washing solutions. Moreover, samples washed with ozone washings showed lower electrolyte leakage than other washing solutions. Samples washed for longer contact time except those washed in ozonized water showed increased microbial numbers during storage. Hence, it has been concluded that longer contact time with ozone has positive effects, whereas the other washing solutions adversely affect the microbial quality and safety aspects of fresh-cut paprika.


Asunto(s)
Capsicum/microbiología , Comida Rápida/microbiología , Conservación de Alimentos/métodos , Frutas/microbiología , Capsicum/química , Recuento de Colonia Microbiana , Desinfectantes/química , Desinfectantes/farmacología , Conductividad Eléctrica , Electrólitos/análisis , Enterobacteriaceae/efectos de los fármacos , Enterobacteriaceae/crecimiento & desarrollo , Enterobacteriaceae/aislamiento & purificación , Comida Rápida/análisis , Manipulación de Alimentos , Embalaje de Alimentos , Frutas/química , Bacterias Aerobias Gramnegativas/efectos de los fármacos , Bacterias Aerobias Gramnegativas/crecimiento & desarrollo , Bacterias Aerobias Gramnegativas/aislamiento & purificación , Humanos , Viabilidad Microbiana , Odorantes , Ozono/química , Ozono/farmacología , Pigmentación , Control de Calidad , Factores de Tiempo
20.
J Food Sci ; 76(6): M387-91, 2011 Aug.
Artículo en Inglés | MEDLINE | ID: mdl-21729071

RESUMEN

The effects of turmeric extract (T), shallot extract (Sh), and their combination (T + Sh) on the quality of vacuum-packaged rainbow trout (Oncorhynchus mykiss) were examined during refrigerated storage (4 ± 1 °C) over a period of 20 d. Fish samples were divided into 4 batches; 3 batches were treated by dipping for 30 min in aqueous solution of turmeric extract (1.5%; v/v), shallot extract (1.5%; v/v), or turmeric and shallot extract combination (1.5%+ 1.5% v/v), while the fourth batch was dipped in distilled water as a control sample. The control and the treated fish samples were analyzed periodically for microbiological (total viable count, psychrotrophic count), chemical (total volatile base nitrogen [TVB-N], peroxide value [PV], and thiobarbituric acid [TBA] value), and sensory characteristics. The results indicated that the effect of the T, Sh, and T + Sh on the fish samples were to enable the good quality characteristics to be retained longer and to extend the shelf life during the refrigerated storage.


Asunto(s)
Curcuma/química , Embalaje de Alimentos , Conservantes de Alimentos/química , Oncorhynchus mykiss , Extractos Vegetales/química , Alimentos Marinos/análisis , Chalotes/química , Animales , Antioxidantes/química , Antioxidantes/farmacología , Femenino , Conservantes de Alimentos/farmacología , Bacterias Aerobias Gramnegativas/efectos de los fármacos , Bacterias Aerobias Gramnegativas/crecimiento & desarrollo , Bacterias Aerobias Gramnegativas/aislamiento & purificación , Humanos , Irán , Masculino , Viabilidad Microbiana/efectos de los fármacos , Oncorhynchus mykiss/microbiología , Extractos Vegetales/farmacología , Control de Calidad , Refrigeración , Alimentos Marinos/microbiología , Sensación , Especias/análisis , Vacio
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