RESUMO
Four quinic acid gallates were isolated from the dried pods of Tara [Caesalpinia spinosa (Molina) Kuntze]. These compounds intensified the susceptibility of methicillin-resistant Staphylococcus aureus (MRSA) to oxacillin. 3,4,5-Tri-O-galloylquinic acid methyl ester (2) was the most effective compound of them.
Assuntos
Antibacterianos/farmacologia , Caesalpinia/química , Infecções Estafilocócicas/tratamento farmacológico , Staphylococcus aureus/efeitos dos fármacos , beta-Lactamas/farmacologia , Antibacterianos/uso terapêutico , Sinergismo Farmacológico , Ácido Gálico/análogos & derivados , Ácido Gálico/química , Ácido Gálico/farmacologia , Resistência a Meticilina , Testes de Sensibilidade Microbiana/métodos , Oxacilina/farmacologia , Extratos Vegetais/química , Extratos Vegetais/farmacologia , Ácido Quínico/análogos & derivados , Ácido Quínico/química , Ácido Quínico/farmacologia , beta-Lactamas/uso terapêuticoRESUMO
Ethyl acetate extracts of the air-dried fruits of Ferula kuhistanica afforded three daucane esters: kuhistanicaol H, I and J, together with nine other known compounds. Their structures were established on the basis of spectroscopic evidence. Isolated compounds in this paper and previously reported compounds from the roots and stems of F. kuhistanica were tested for antibacterial activity. Some of them were selectively toxic against Gram-positive bacteria, including methicillin-sensitive and methicillin-resistant Staphylococcus aureus (MSSA and MRSA).
Assuntos
Ferula/química , Sesquiterpenos/farmacologia , Staphylococcus aureus/efeitos dos fármacos , Staphylococcus epidermidis/efeitos dos fármacos , Antibacterianos/química , Antibacterianos/isolamento & purificação , Antibacterianos/farmacologia , Frutas/química , Meticilina/farmacologia , Sesquiterpenos/química , Sesquiterpenos/isolamento & purificaçãoRESUMO
A careful investigation of the subterranean part of Vitex rotundifolia has shown that this plant contains five novel lignans having a 1-phenylnaphthalene-type skeleton together with four known lignans. These structures were elucidated on the basis of spectroscopic data. Furthermore, some of the isolated compounds showed antibacterial activity against methicillin-resistant Staphylococcus aureus (MRSA).
Assuntos
Antibacterianos/isolamento & purificação , Resistência a Meticilina , Naftalenos/isolamento & purificação , Naftalenos/farmacologia , Plantas Medicinais/química , Staphylococcus aureus/efeitos dos fármacos , Antibacterianos/farmacologia , Ásia , Espectrometria de Massas , Testes de Sensibilidade Microbiana , Raízes de Plantas/química , Espectrofotometria Infravermelho , Espectrofotometria UltravioletaRESUMO
A crude extract prepared from Scutellaria barbata D. Don (Lamiaceae) was analyzed in the effort to discover antibacterial compounds against high-level strains of methicillin-resistant Staphylococcus aureus (MRSA). Apigenin and luteolin were isolated from the plant as active constituents against the bacteria. These flavonoid congeners were selectively toxic to S. aureus, including the MRSA and methicillin-sensitive S. aureus strains.
Assuntos
Antibacterianos/isolamento & purificação , Flavonoides/isolamento & purificação , Lamiaceae/química , Resistência a Meticilina , Staphylococcus aureus/efeitos dos fármacos , Antibacterianos/farmacologia , Sequência de Bases , Primers do DNA , Flavonoides/farmacologia , Testes de Sensibilidade MicrobianaRESUMO
This study was conducted to find constituents of an annual herb, Xanthium sibiricum Patr er Widd, with effective antibacterial activity against methicillin-resistant Staphylococcus aureus (MRSA). By monitoring antibacterial activity against MRSA strains, it was shown that a sesquiterpene lactone, identified as [3aR-(3a alpha, 7 beta,8a beta)]-3,3a,4,7,8,8a-hexahydro-7- methyl-3-methylene-6-(3-oxo-1-butenyl)-2H-cyclohepta[b]furan-2-one, or xanthatin, isolated from leaves of the herb, had outstandingly potent activity against S. aureus species, including MRSA; its activity against MRSA and MSSA strains was similar. Other bacteria, e.g. Staphylococcus epidermidis, Klebsiella pneumoniae, Bacillus cereus, Pseudomonas aeruginosa and Salmonella typhi, were also susceptible at the concentrations tested but the compound had no inhibitory effect on some other bacteria, including Escherichia coli. The results show that xanthatin has outstandingly potent activity against strains of S. aureus but that the activity of the compound is highly species-specific.
Assuntos
Antibacterianos/química , Antibacterianos/farmacologia , Furanos/química , Furanos/farmacologia , Resistência a Meticilina , Plantas Medicinais/química , Staphylococcus aureus/efeitos dos fármacos , Bactérias/efeitos dos fármacos , Cromatografia em Camada Fina , Testes de Sensibilidade Microbiana , Extratos Vegetais/química , Extratos Vegetais/farmacologiaRESUMO
Examination of the EtOH extract of the fruiting bodies of Terminalia chebula RETZ. led to the isolation of two potent antimicrobial substances against even methicillin-resistant strains of Staphylococcus aureus. On the basis of spectroscopic evidence, the two isolates have been identified as gallic acid and its ethyl ester.