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1.
Nat Prod Commun ; 8(1): 59-61, 2013 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-23472460

RESUMO

Isophorone (3,5,5-trimethyl-2-cyclohexen-1-one), a monoterpene, and the structurally related 1,8-cineole and camphor, have demonstrated a protective effect against cancer, biological activity against a variety of microorganisms, and anti-oxidant properties. The derivatization of isophorone is, therefore, an important field of xenobiochemistry, pharmacology and toxicology. The aim of this study was to obtain derivatives of isophorone through microbial biotransformation and evaluate the biotransformation metabolites as potential antimicrobial agents. Incubation of isophorone with the fungi Alternaria alternata and Neurospora crassa afforded 4a-hydroxy- and 7-hydroxy-isophorone as transformation metabolites. The antimicrobial activities of isophorone and the metabolites were evaluated in vitro both by using agar dilution and microdilution methods. However, no significant antibacterial activity was observed when compared with those of standard substances.


Assuntos
Alternaria/metabolismo , Anti-Infecciosos/análise , Cicloexanonas/metabolismo , Neurospora crassa/metabolismo , Biotransformação , Cicloexanonas/química , Testes de Sensibilidade Microbiana
2.
J Hazard Mater ; 165(1-3): 279-84, 2009 Jun 15.
Artigo em Inglês | MEDLINE | ID: mdl-19013018

RESUMO

Biosorption potential of dried anaerobic sludge (DAS) for Burazol Blue ED (BB) was studied with respect to pH, equilibrium time, initial dye concentrations and temperature to determine equilibrium and kinetic models. The most suitable pH, equilibrium time and initial dye concentration were determined as 0.5+/-0.03, 75 min and 150 mg/L, respectively, at a biomass dosage of 0.4 g/L and 25 degrees C+/-1.0. The equilibrium data was best described by the Langmuir isotherm model. Maximum uptake capacity (q(m)) of DAS for the dyestuff (BB) were 118.3, 125.8 and 127.5mg/g biomass at temperatures of 25, 40 and 50 degrees C, respectively, indicating that the biosorption process is spontaneous and favored at higher temperatures. The overall biosorption process was best described by pseudo-second-order kinetic model. Gibbs free energy changes were calculated as -356.8, -519.7 and -520.6J/mol at 25, 40 and 50 degrees C, respectively.


Assuntos
Compostos Azo/isolamento & purificação , Biodegradação Ambiental , Corantes/isolamento & purificação , Naftalenossulfonatos/isolamento & purificação , Esgotos/microbiologia , Adsorção , Bactérias Anaeróbias , Biomassa , Resíduos Industriais , Cinética , Temperatura , Termodinâmica
3.
Environ Monit Assess ; 148(1-4): 477-84, 2009 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-18270800

RESUMO

The spores of Cladosporium spp. and Alternaria spp., commonly described as the most allergenic spores, were collected by means of Durham gravimetric sampler from the Sivrihisar (Eskisehir) atmosphere throughout 2005 to 2006. The weekly variations in spores/cm(2) of Cladosporium and Alternaria were recorded. During this period, a total of 6,198 spores belonging to Cladosporium spp. and Alternaria spp. were recorded. Of these spores, 2,969 were identified in 2005 and 3,229 in 2006. While 69.55% of the total spores were those of Cladosporium spp., 30.45% were Alternaria spp. Relationships between airborne fungal spore presence and weather conditions were examined statistically. A Shapiro-Wilk test revealed that the airborne spores of Cladosporium spp. and Alternaria spp. had a normal distribution. Following this, Chi-square test, t test and Pearson correlation analysis were performed. The effects of temperature and relative humidity on the spore numbers of Cladosporium spp. and Alternaria spp. were significant according to the month in which they were collected (p < 0.01). The spore concentrations of each species reached to their highest levels in June 2006.


Assuntos
Microbiologia do Ar , Alternaria/imunologia , Cladosporium/imunologia , Esporos Fúngicos/imunologia , Alérgenos/análise , Monitoramento Ambiental , Humanos , Turquia , Tempo (Meteorologia)
4.
Environ Monit Assess ; 144(1-3): 269-76, 2008 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-17929181

RESUMO

The application of different multivariate statistical approaches for the interpretation of a complex data matrix obtained during the period 2004-2005 from Uluabat Lake surface water is presented in this study. The dataset consists of the analytical results of a 1 year-survey conducted in 12 sampling stations in the Lake. Twelve parameters (T, pH, DO, PO(-3)(4), NH(4)-N, NO(2)-N, NO(3)-N, SO(3-)(4), BOD, COD, TC, FC) were monitored in the sampling sites on a monthly basis (except December 2004, January and February 2005, a total of 1,296 observations). The dataset was treated using cluster analysis, principle component analysis and factor analysis on principle components. Cluster analysis revealed two different groups of similarities between the sampling sites, reflecting different physicochemical properties and pollution levels in the studied water system. Three latent factors were identified as responsible for the data structure, explaining 77.35% of total variance in the dataset. The first factor called the microbiological factor explained 32.34% of the total variance. The second factor named the organic-nutrient factors explained 25.46% and the third factor called physicochemical factors explained 19.54% of the variances, respectively.


Assuntos
Monitoramento Ambiental/métodos , Água Doce/análise , Análise Multivariada , Poluentes Químicos da Água/análise , Abastecimento de Água/análise , Animais , Eutrofização , Humanos , Turquia , Poluição da Água
5.
J Hazard Mater ; 143(1-2): 335-40, 2007 May 08.
Artigo em Inglês | MEDLINE | ID: mdl-17034944

RESUMO

Biosorption of Reactive Black 5 (RB 5) dye onto dried Penicillium restrictum biomass was studied with respect to pH, contact time, biosorbent and dye concentrations. The effect of temperature on the biosorption efficiency was also carried out and the kinetic parameters were determined. Optimum initial pH, equilibrium time and biomass concentration for RB 5 dye were found to be 1.0, 75 min and 0.4 g dm(-3) at 20 degrees C, respectively. The maximum biosorption capacities (q(max)) of RB 5 dye onto dried P. restrictum biomass were 98.33 and 112.50mg (g biomass)(-1) at 175 mg dm(-3) initial dye concentration at 20 and 50 degrees C, respectively, and it was 142.04 mg (g biomass)(-1) at 200 mg dm(-3) initial dye concentration at 35 degrees C. The results indicate that the biosorption process obeys a pseudo-second-order kinetic model.


Assuntos
Naftalenossulfonatos/química , Penicillium/química , Adsorção , Biomassa , Concentração de Íons de Hidrogênio , Resíduos Industriais , Cinética , Temperatura , Indústria Têxtil , Fatores de Tempo
6.
Z Naturforsch C J Biosci ; 60(9-10): 686-92, 2005.
Artigo em Inglês | MEDLINE | ID: mdl-16320609

RESUMO

The in vitro antibacterial and antifungal activities of demethoxyviridin and some synthetic analogues were evaluated by the agar diffusion method. The minimum inhibitory concentrations (MIC) of the active compounds were also determined by the agar dilution method. Demethoxyviridin (1) showed moderate antibacterial activity against most of the strains tested. 1alpha-Hydroxydemethoxyviridin (3) showed antibacterial activity and the most potent in vitro antifungal activity with MIC of 20 microg/ml (0.062 mM) against Aspergillus niger, A. fumigatus, A. flavus, A. parasiticus, Fusarium solani, F. graminarum, Geotrichum candidum whereas 5'-methylfuro-(4',3',2'-4,5,6)androst-5-ene-3,17-dione (7) exhibited very weak antifungal activity against Candida albicans only.


Assuntos
Androstenos/síntese química , Androstenos/farmacologia , Antibacterianos/farmacologia , Antifúngicos/farmacologia , Inibidores Enzimáticos/síntese química , Inibidores Enzimáticos/farmacologia , Androstenos/metabolismo , Ascomicetos/metabolismo , Bactérias/efeitos dos fármacos , Fungos/efeitos dos fármacos , Testes de Sensibilidade Microbiana , Estrutura Molecular , Fosfolipases/antagonistas & inibidores , Relação Estrutura-Atividade
7.
J Basic Microbiol ; 45(4): 279-93, 2005.
Artigo em Inglês | MEDLINE | ID: mdl-16028200

RESUMO

The soil microfungi flora was investigated in four locations of Eskisehir (Turkey). 56 soil samples were seasonaly collected from 14 stations in the areas of Karacahöyük, Bahçecik, OGU I, and OGU II. A total of 110 species belonging to 32 genera were encountered including Absidia, Acremonium, Alternaria, Aspergillus, Beauveria, Botryoderma, Chaetomium, Chrysosporium, Cladosporium, Eupenicillium, Eurotium, Fusarium, Geotrichum, Gliocladium, Gonytrichum, Metarrhizium, Mucor, Myrothecium, Paecilomyces, Penicillium, Phoma, Plectosphaerella, Rhizoctania, Rhizopus, Scopulariopsis, Septonema, Stachybotrys, Trichocladium, Trichoderma, Ulocladium, Verticillium, and Wardomyces. Twenty five species were more frequent (all locations) while twenty seven species were rare (only one sample). Mainly, Acremonium kiliense, Aspergillus ochraceus, A. terricola var. americanus, A. versicolor, Cladosporium cladosporioides, Fusarium oxysporum, F. solani, Gliocladium roseum, Penicillium chrysogenum, P. corylophum, P. expansum, P. griseofulvum, P. implicatum, P. restrictum, and Stachybotrys chartarum were the most common and abundant microfungi in all locations. Five species Aspergillus subsessilis, A. terreus var. africanus, Eupenicillium egyptiacum, Paecilomyces ramosus, and Penicillium novae-zeelandiae are likely to be newly recorded for Turkey. The microfungi number in Eskisehir soils was between 25,000-234,000 CFU/g (mean value at 126,375 CFU/g).


Assuntos
Fungos/isolamento & purificação , Microbiologia do Solo , Estações do Ano
8.
Mikrobiyol Bul ; 36(3-4): 259-69, 2002.
Artigo em Turco | MEDLINE | ID: mdl-12838659

RESUMO

Bactericidal efficacy of seven different disinfectants (chlorhexidine gluconate, povidone-iodine, glutaraldehyde, benzalkonium chloride, sodium hypochloride, ethoxydiamino acridine, the mixture of "12% ethandiol + 0.5% pentanediol + 7.5% didecyldimethylammonium cloride") commonly used at Osmangazi University, Medical Faculty Hospital, was investigated against frequent nosocomial bacterial pathogens (19 Gram-negative and 25 Gram-positive strains) by using modified Kelsey-Sykes method. Chlorhexidine gluconate, povidone-iodine and glutaraldehyde were determined as the most effective disinfectants against all of the pathogens. There was no significant difference in terms of biocide resistance between antibiotic sensitive and resistant strains. All of the P. aeruginosa strains were found to be resistant to 0.01% benzalkonium chloride and 0.25%, 0.5% and 1% concentrations of "12% ethandiol + 0.5% pentanediol + 7.5% didecyldimethyl ammonium cloride" mixture. One vancomycin resistant E. faecium strain and one extended spectrum beta-lactamase (ESBL) positive K. pneumoniae strain were found to be resistant to 0.55% sodium hypochloride. Ethoxydiamino acridine showed little or no activity against all tested strains.


Assuntos
Anti-Infecciosos Locais/farmacologia , Infecção Hospitalar/microbiologia , Desinfetantes/farmacologia , Bactérias Gram-Negativas/efeitos dos fármacos , Bactérias Gram-Positivas/efeitos dos fármacos , Farmacorresistência Bacteriana , Humanos , Testes de Sensibilidade Microbiana
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