RESUMEN
Bacillus subtilis strains are known to produce a vast array of antimicrobial compounds. However, some compounds remain to be identified. Disk assays performed in vitro with Bacillus subtilis CU12 showed a significant reduction in mycelial growth of Alternaria solani, Botrytis cinerea, Fusarium sambucinum, and Pythium sulcatum. Crude B. subtilis culture filtrates were subsequently extracted with ethyl acetate and butanol. A bioassay guided purification procedure revealed the presence of one major antifungal compound in the butanol extract. Purification of the compound was performed using a reverse-phase C18 solid phase extraction (SPE) cartridge and flash column chromatography. NMR data showed that the main antimicrobial compound was a cyclic dimer of 3-hydroxypropionaldehyde (HPA). This study demonstrated the antimicrobial activity of B. subtilis strain CU12 against phytopathogenic microorganisms is mediated at least in part by the production of HPA. It also suggests that this B. subtilis strain could be effective at controlling pathogens through protection of its ecological niche by antibiosis.
Asunto(s)
Antiinfecciosos/metabolismo , Bacillus subtilis/metabolismo , Gliceraldehído/análogos & derivados , Propano/metabolismo , Alternaria/efectos de los fármacos , Antiinfecciosos/aislamiento & purificación , Antiinfecciosos/farmacología , Bacillus subtilis/química , Botrytis/efectos de los fármacos , Cromatografía de Fase Inversa , Dimerización , Fusarium/efectos de los fármacos , Gliceraldehído/aislamiento & purificación , Gliceraldehído/metabolismo , Gliceraldehído/farmacología , Pruebas de Sensibilidad Microbiana , Propano/aislamiento & purificación , Propano/farmacología , Pythium/efectos de los fármacos , Extracción en Fase SólidaRESUMEN
Investigations of the stem and root bark of Myrica arborea (Myricaceae) have yielded two novel diarylheptanoids, myricarborin and 11-O-beta-D-xylopyranosylmyricanol along with the known myricanol and 5-O-beta-D-glucopyranosylmyricanol. The structures of the novel compounds were determined by spectroscopic methods.
Asunto(s)
Heptanos/aislamiento & purificación , Rosales/química , Heptanos/química , Estructura Molecular , Análisis EspectralRESUMEN
A new Diels-Alder-type adduct, dorstenone (1), was isolated from Dorstenia barteri together with three known flavonoids, 4,2', 4'-trihydoxy-3'-prenylchalcone; 4,2',4'-trihydoxy-3, 3'-diprenylchalcone; and 5,7,4'-trihydoxy-8-prenylflavone. The structure of 1 was elucidated using a combination of highfield NMR techniques, particularly, gradient-enhanced HMQC and HMBC.
Asunto(s)
Flavonoides/aislamiento & purificación , Plantas Medicinales/química , Flavonoides/química , Espectroscopía de Resonancia Magnética , Estructura Molecular , Análisis EspectralRESUMEN
Four urea derivatives were isolated from the roots of Pentadiplandra brazzeana, and their structures were elucidated by spectroscopic techniques. N-Benzyl-N'-(4-methoxybenzyl)urea (1) is a new compound, although N,N'-di-(4-methoxybenzyl)urea (2), N,N'-dibenzylurea (3), and p-methoxythiobenzaldehyde (4) are reported from a natural source for the first time.
Asunto(s)
Plantas Medicinales/química , Urea/química , Estructura Molecular , Análisis Espectral , Urea/aislamiento & purificaciónRESUMEN
A new isodaucane sesquiterpenoid, 6,7,10-trihydoxyisodaucane, was isolated from the fruits of Reneilmia cincinnata, together with the known sesquiterpenoids oplodiol, oplopanone, 5E,10(14)-germacradien-1 beta, 4 beta-diol, 1(10)E,5E-germacradien-4 alpha-ol and eudesman-1,4,7-triol. A large amount of 5-hydroxy-3,7,4'-trimethoxyflavone was also isolated. Their structures were established by NMR techniques using 1D and 2D experiments. Three of the known sesquirernenoids exhibited noteworthy anti-plasmodial activity against Plasmodium falciparum strains.