RESUMEN
The twigs and leaves of Blepharispermum hirtum Oliver (Asteraceae) were investigated for their larvicidal and antimicrobial activity. Fractionation of the extracts of the twigs, directed by brine shrimp test and antibacterial activities, led to the isolation of compounds 1-4; two of which are new ent-kaurene diterpenoids, blepharispins A and B (1 and 2, resp.). The structures of compounds 1 and 2 were established from spectral data. The absolute configuration at C(15) in 1 was inferred from Mosher ester analysis and relative configurations were suggested by a NOESY experiment. Compound 4 was significantly larvicidal to newly hatched naupleii of Artemia salina L. (BST LC(50)=1.3 (3.7-0.0) microg/ml), but the blepharispins were not (BST LC(50) > 500 microg/ml). Nevertheless, compound 1 inhibited the growth of Staphylococcus aureus and Bacillus subtilis at a MIC value of 62.5 microg/ml. The significance of the bioactivity results and the presence of ent-kaurene diterpenoids in B. hirtum are discussed from biosynthetic and local utilization viewpoints.
Asunto(s)
Antiinfecciosos/química , Antiinfecciosos/farmacología , Asteraceae/química , Diterpenos de Tipo Kaurano/química , Diterpenos de Tipo Kaurano/farmacología , Animales , Antiinfecciosos/aislamiento & purificación , Artemia/efectos de los fármacos , Bacterias/efectos de los fármacos , Diterpenos de Tipo Kaurano/aislamiento & purificación , Hongos/efectos de los fármacos , Larva/efectos de los fármacos , Pruebas de Sensibilidad Microbiana , Estructura Molecular , Extractos Vegetales/química , Extractos Vegetales/aislamiento & purificación , Extractos Vegetales/farmacología , Hojas de la Planta/químicaRESUMEN
The chemotypes of Ocimum forskolei Benth and Ocimum basilicum L. growing wild in Oman have been established by (13)C-NMR analyses of the vegetative and floral oils of the plants. The chemotypes, estragole for O. forskolei and linalool for O. basilicum, suggested by (13)C-NMR fingerprinting were also confirmed by GC-FID and GC/MS analyses. The oil of O. forskolei demonstrated better activities against bacteria and dermatophytes. The significance of the presence of estragole and linalool in the volatile oils of plants whose fragrances are traditionally inhaled, added to food, or rubbed on the skin are discussed.
Asunto(s)
Anisoles/química , Monoterpenos/química , Ocimum basilicum/química , Ocimum/química , Monoterpenos Acíclicos , Derivados de Alilbenceno , Anisoles/análisis , Anisoles/farmacología , Flores/química , Hongos/efectos de los fármacos , Bacterias Gramnegativas/efectos de los fármacos , Bacterias Grampositivas/efectos de los fármacos , Espectroscopía de Resonancia Magnética , Pruebas de Sensibilidad Microbiana , Monoterpenos/análisis , Monoterpenos/farmacología , Hojas de la Planta/química , Aceites de Plantas/análisis , Aceites de Plantas/química , Aceites de Plantas/farmacología , Plantas Medicinales/químicaRESUMEN
The chemical composition of the essential oil of Haplophyllum tuberculatum (Forsskal) A. Juss (Rutaceae) was analyzed by gas chromatography-mass spectral (GC-MS) and 13C NMR spectroscopy. Thirty compounds, constituting about 99.7% of the total oil, were identified. The most abundant oil components are beta-phellandrene (23.3%), limonene (12.6%), (Z)-beta-ocimene (12.3%), beta-caryophyllene (11.6%), myrcene (11.3%), and alpha-phellandrene (10.9%). Ten microlitres (25 mg) of pure oil partially inhibited the growth of Escherichia coli, Salmonella choleraesuis, and Bacillus subtilis to the same extent as 0.10 microg of gentamycin sulfate. The oil also affected the mycelial growth of Curvularia lunata and Fusarium oxysporium in a dose-dependent manner but had no effect on the germination of their spores.
Asunto(s)
Antibacterianos/química , Antifúngicos/química , Aceites Volátiles/química , Rutaceae/química , Flores/química , Cromatografía de Gases y Espectrometría de Masas , Bacterias Gramnegativas/efectos de los fármacos , Espectroscopía de Resonancia Magnética , Pruebas de Sensibilidad Microbiana , Hongos Mitospóricos/efectos de los fármacos , Omán , Extractos Vegetales/química , Tallos de la Planta/químicaRESUMEN
Two new sesquiterpenes, godotol A (1) and godotol B (2), were isolated from Pluchea arabica. Their structures were determined by analysis of NMR data. The absolute configurations of 1 and 2 were established by Mosher ester methodology. The godotols displayed weak activity against bacteria and the brine shrimp larvae. They were also inactive in the DPPH antioxidant assay.