Subject(s)
Antibiotics, Antineoplastic/isolation & purification , Antifungal Agents/isolation & purification , Mitosporic Fungi/chemistry , Trichothecenes/isolation & purification , Antibiotics, Antineoplastic/chemistry , Antibiotics, Antineoplastic/pharmacology , Antifungal Agents/chemistry , Antifungal Agents/pharmacology , Crystallography, X-Ray , Humans , Magnetic Resonance Spectroscopy , Soil Microbiology , Trichothecenes/chemistry , Trichothecenes/pharmacology , Tumor Cells, CulturedABSTRACT
Bioassay-guided fractionation of the organic extract from a culture of Phomopsis longicolla, an endophytic fungus of the endangered mint Dicerandra frutescens, led to the isolation of dicerandrols A, B, and C. Extensive NMR and HRFABMS experiments were used to identify these new yellow antibiotic and cytotoxic compounds as 2,2'-dimeric tetrahydroxanthones.
Subject(s)
Antibiotics, Antineoplastic/isolation & purification , Ascomycota/chemistry , Xanthenes/isolation & purification , Xanthones , Antibiotics, Antineoplastic/chemistry , Antibiotics, Antineoplastic/pharmacology , Bacillus subtilis/drug effects , Colonic Neoplasms , Florida , Geotrichum/drug effects , Humans , Lamiaceae , Lung Neoplasms , Magnetic Resonance Spectroscopy , Molecular Structure , Saccharomyces cerevisiae/drug effects , Spectrophotometry, Infrared , Spectrophotometry, Ultraviolet , Staphylococcus aureus/drug effects , Stereoisomerism , Tumor Cells, Cultured/drug effects , Tumor Cells, Cultured/metabolism , Xanthenes/chemistry , Xanthenes/pharmacologyABSTRACT
[structure] Organic extracts from cultures of endophytic fungi collected in the Guanacaste Conservation Area of Costa Rica were screened for antibiotic activity. Two endophytes CR200 (Cytospora sp.) and CR146 (Diaporthe sp.) were found to have potent antibiotic activity. Bioassay-guided fractionation of the extracts from these fungi led to the identification of cytosporones D and E, antibacterial active trihydroxybenzene lactones, and three related but inactive metabolites. The five new octaketides were characterized using X-ray crystallography and NMR.
Subject(s)
Anti-Bacterial Agents/isolation & purification , Benzopyrans/isolation & purification , Lactones/isolation & purification , Mitosporic Fungi/metabolism , Anti-Bacterial Agents/chemistry , Anti-Bacterial Agents/pharmacology , Antifungal Agents/chemistry , Antifungal Agents/isolation & purification , Antifungal Agents/pharmacology , Bacteria/drug effects , Benzopyrans/chemistry , Benzopyrans/pharmacology , Crystallography, X-Ray , Fermentation , Lactones/chemistry , Lactones/pharmacology , Magnetic Resonance Spectroscopy , Microbial Sensitivity Tests , Mitosporic Fungi/chemistry , Models, MolecularABSTRACT
Three new cytotoxic cytochalasins (1-3) and the previously reported cytochalasin E (4) were isolated from a culture of the endophytic fungus Rhinocladiella sp. using bioassay-guided fractionation. Extensive NMR and HRCIMS experiments identified these new compounds as 22-oxa-[12]-cytochalasins.