RESUMO
Three new alkaloids, phomapyrrolidones A-C (1-3), bearing a cyclopenta[b]fluorene ring system were isolated from the mycelium extract of the endophytic fungal strain Phoma sp. NRRL 46751, inhabiting Saurauia scaberrinae. Methylation of 1 afforded its N-methyl derivative 4. The planar structures and relative configurations of 1-4 were elucidated by extensive spectroscopic analysis. Phomapyrrolidones B (2) and C (3) exhibited weak antitubercular activity at subcytotoxic concentrations.
Assuntos
Actinidiaceae/microbiologia , Alcaloides/isolamento & purificação , Alcaloides/farmacologia , Antituberculosos/isolamento & purificação , Antituberculosos/farmacologia , Ascomicetos/química , Mycobacterium tuberculosis/efeitos dos fármacos , Succinimidas/isolamento & purificação , Succinimidas/farmacologia , Alcaloides/química , Animais , Antituberculosos/química , Chlorocebus aethiops , Ensaios de Seleção de Medicamentos Antitumorais , Feminino , Humanos , Masculino , Estrutura Molecular , Micélio/química , Ressonância Magnética Nuclear Biomolecular , Succinimidas/química , Células VeroRESUMO
A novel species, Metschnikowia cibodasensis, is proposed to accommodate eight strains (ID03- 0093(T), ID03-0094, ID03-0095, ID03-0096, ID03-0097, ID03-0098, ID03-0099, and ID03-0109) isolated from flowers of Saurauia pendula, Berberis nepalensis, and Brunfelsia americana in Cibodas Botanical Garden, West Java, Indonesia. The type strain of M. cibodasensis is ID03- 0093(T) (= NBRC 101693(T) =UICC Y-335(T) = BTCC-Y25(T)). The common features of M. cibodasensis are a spherical to ellipsoidopedunculate shaped ascus, which contains one or two needleshaped ascospores, and lyse at maturity. Asci generally develop directly from vegetative cells but sometimes from chlamydospores. The neighbor-joining tree based on the D1/D2 domain of nuclear large subunit (nLSU) ribosomal DNA sequences strongly supports that M. cibodasensis (eight strains) and its closest teleomorphic species, M. reukaufii, are different species by a 100% bootstrap value. The type strain of M. cibodasensis, ID03-0093(T), differed from M. reukaufii NBRC 1679(T) by six nt (five substitutions and one deletion) in their D1/D2 region of nLSU rDNA, and by 18 nt (five deletions, four insertions, and nine substitutions) in their internal transcribed spacer regions of rDNA, respectively. Four strains representative of M. cibodasensis (ID03-0093(T), ID03-0095, ID03-0096, and ID03-0099) showed a mol% G+C content of 44.05 ± 0.25%, whereas that of M. reukaufii NBRC 1679(T) was 41.3%. The low value of DNADNA homology (5-16%) in four strains of M. cibodasensis and M. reukaufii NBRC 1679(T) strongly supported that these strains represent a distinct species.
Assuntos
Flores/microbiologia , Metschnikowia/classificação , Metschnikowia/isolamento & purificação , Actinidiaceae/microbiologia , Composição de Bases , Berberis/microbiologia , Análise por Conglomerados , DNA Fúngico/química , DNA Fúngico/genética , DNA Ribossômico/química , DNA Ribossômico/genética , DNA Espaçador Ribossômico/química , DNA Espaçador Ribossômico/genética , Genes de RNAr , Indonésia , Metschnikowia/citologia , Metschnikowia/genética , Dados de Sequência Molecular , Filogenia , RNA Fúngico/genética , RNA Ribossômico/genética , Análise de Sequência de DNA , Solanaceae/microbiologiaRESUMO
Phomodione, [(4aS(*),9bR(*))-2,6-diacetyl-7-hydroxy-4a,9-dimethoxy-8,9b-dimethyl-4a.9b-dihydrodibenzo[b,d]furan-1,3(2H,4H)-dione], an usnic acid derivative, was isolated from culture broth of a Phoma species, discovered as an endophyte on a Guinea plant (Saurauia scaberrinae). It was identified using NMR, X-ray crystallography, high resolution mass spectrometry, as well as infrared and Raman spectroscopy. In addition to phomodione, usnic acid and cercosporamide, known compounds with antibiotic activity, were also found in the culture medium. Phomodione exhibited a minimum inhibitory concentration of 1.6 microg/mL against Staphylococcus aureus using the disk diffusion assay, and was active against a representative oomycete, ascomycete and basidiomycete at between three and eight micro-grams per mL.
