RESUMEN
Caboxamycin, a new benzoxazole antibiotic, was detected by HPLC-diode array screening in extracts of the marine strain Streptomyces sp. NTK 937, which was isolated from deep-sea sediment collected in the Canary Basin. The structure of caboxamycin was determined by mass spectrometry, NMR experiments and X-ray analysis. It showed inhibitory activity against Gram-positive bacteria, selected human tumor cell lines and the enzyme phosphodiesterase.
Asunto(s)
Antibacterianos/biosíntesis , Antibacterianos/farmacología , Benzoxazoles/farmacología , Streptomyces/metabolismo , Antibacterianos/aislamiento & purificación , Antibióticos Antineoplásicos/farmacología , Benzoxazoles/aislamiento & purificación , Benzoxazoles/metabolismo , Línea Celular Tumoral , Supervivencia Celular , Evaluación Preclínica de Medicamentos , Ensayos de Selección de Medicamentos Antitumorales , Fermentación , Bacterias Grampositivas/efectos de los fármacos , Humanos , Espectroscopía de Resonancia Magnética , Pruebas de Sensibilidad Microbiana , Modelos Moleculares , Conformación Molecular , Agua de Mar/microbiología , Espectrometría de Masa por Ionización de Electrospray , Espectrofotometría Infrarroja , Espectrofotometría Ultravioleta , Streptomyces/química , Microbiología del AguaRESUMEN
The emergence of antibiotic resistant H. pylori strains has necessitated the identification of alternative additive therapies for the treatment of this infection. The study tested whether a specific pine bark extract (Pycnogenol is effective in inhibiting the growth and adherence of H. pylori in vitro. Inhibition of H. pylori growth by Pycnogenol was tested in liquid medium as well as in an in vitro model by using sessile bacteria attached to AGS cells. Adherence was determined by co-incubation of gastric cells with Pycnogenol and H. pylori in vitro. Pycnogenol inhibited H. pylori growth in suspension with an MIC(50) of 12.5 microg/mL. Growth of H. pylori in infected cells was reduced to 10% of the control value by 125 microg/mL Pycnogenol. Adherence of H. pylori to gastric cells was reduced by 70% after 3 h incubation with 125 microg/mL Pycnogenol. The results show a significant, yet limited inhibition of growth and adherence of H. pylori to gastric cells by Pycnogenol. In vivo studies have to demonstrate the clinical relevance of these findings.