RESUMEN
The isolation of difficidin (1) and oxydifficidin (2) from fermentation broth of Bacillus subtilis ATCC 39320 and the physico-chemical characterization of these labile antibiotics are described. The structures of the compounds represent a new class of antibiotics, characterized as highly unsaturated 22-membered macrolide phosphates. Difficidin and oxydifficidin undergo reversible thermal isomerization to 3 and 4 respectively. Biological evaluation of the isomers is presented.
Asunto(s)
Antibacterianos , Fosfatasa Alcalina , Fenómenos Químicos , Química Física , Concentración de Iones de Hidrógeno , Hidroxilamina , Hidroxilaminas/farmacología , Isomerismo , Lactonas/aislamiento & purificación , Lactonas/farmacología , Espectroscopía de Resonancia Magnética , Pruebas de Sensibilidad Microbiana , TemperaturaRESUMEN
Restricticin (1) is a naturally-occurring antifungal agent which contains triene, pyran and glycine ester functionalities and is unrelated to any previously known family of natural products. This unstable compound, as well as its corresponding N,N-dimethyl derivative (2), have been produced and isolated from both solid and liquid fermentations of Penicillium restrictum. The desglycyl hydrolysis product, restrictinol (3), was produced via the hydrolysis of pure restricticin and as an artifact of the isolation of restricticin.
Asunto(s)
Antifúngicos/aislamiento & purificación , Glicina/análogos & derivados , Piranos/aislamiento & purificación , Antifúngicos/farmacología , Estabilidad de Medicamentos , Fermentación , Glicina/aislamiento & purificación , Glicina/farmacología , Pruebas de Sensibilidad Microbiana , Penicillium/análisis , Penicillium/metabolismo , Piranos/farmacologíaRESUMEN
The avermectins, a family of new anthelmintic agents, were isolated from the mycelia of Streptomyces avermitilis. Four closely related major components and four homologous minor components were separated from the complex. Solvent extraction, solvent partition, and adsorption methods were used to isolate and purify the complex; novel partition chromatography systems using Sephadex LH-20 were used to separate the components. A reverse-phase high-pressure liquid chromatography assay for the quantitative determination of all components was used extensively to monitor the purification methods.