ABSTRACT
A new compound 6-formamide-chetomin (1) together with chetomin (2) was isolated from solid fermentation products of the endophytic fungus Chaetomium sp. M336, which were elucidated by extensive spectroscopic analyses, including 1D and 2D NMR, and HR-ESI-MS experiments. The bioassay result showed that compound 1 had strong antibacterial activity against Escherichia coli, Staphylococcus aureus, Salmonella typhimurium ATCC 6539 and Enterococcus faecalis with minimum inhibitory concentration (MIC) value of 0.78 µg/mL; meanwhile it exhibited strong cytotoxicity with IC50 values of 21.6-27.1 nM against cell lines HeLa, SGC-7901 and A549.
Subject(s)
Anti-Bacterial Agents/pharmacology , Antineoplastic Agents/pharmacology , Chaetomium/chemistry , Formamides/pharmacology , Anti-Bacterial Agents/chemistry , Antineoplastic Agents/chemistry , Cell Line, Tumor , Disulfides/chemistry , Disulfides/pharmacology , Endophytes/chemistry , Enterococcus faecalis/drug effects , Escherichia coli/drug effects , Formamides/chemistry , HeLa Cells , Humans , Indole Alkaloids/chemistry , Indole Alkaloids/pharmacology , Microbial Sensitivity Tests , Molecular Structure , Salmonella typhimurium/drug effects , Staphylococcus aureus/drug effectsABSTRACT
An endophytic fungus, Chaetomium sp. M453, was isolated from Huperzia serrata (Thunb. ex Murray) Trev. and subjected to phytochemical investigation. Three unusual C25 steroids, neocyclocitrinols E-G (1-3), and 3ß-hydroxy-5,9-epoxy-(22E,24R)-ergosta-7,22-dien-6-one (4) together with three known steroids were isolated from solid fermentation products of the fungus, which were elucidated by extensive spectroscopic analyses, including 1D-, 2D-NMR, and HR-ESI-MS experiments. The absolute configuration of 1 was determined by X-ray crystallographic analysis and CD analyses. The acetylcholinesterase inhibitory activities of compounds 1-4 were tested in vitro. Compound 4 showed weak acetylcholinesterase inhibitory activity.
Subject(s)
Chaetomium/chemistry , Cholinesterase Inhibitors/chemistry , Huperzia/microbiology , Steroids/chemistry , Cell Line, Tumor , Cholinesterase Inhibitors/isolation & purification , Humans , Molecular Structure , Plants, Medicinal/microbiology , Steroids/isolation & purificationABSTRACT
The white pine blister rust caused by Cronartium ribicola is a severe disease of Pinus armandii Franch in Sichuan Province, China. A mycoparasite was isolated from aeciospore piles of C. ribicola and identified as Pestalotipsis sp. The chemical constituents were investigated and nine new polyketides, named pestalotic acids A-I (1-9), were isolated from solid fermentation products of Pestalotiopsis sp. cr014. Their structures were elucidated by extensive spectroscopic methods, including 1D- and 2D- NMR, HR-MS experiments. Compounds 2-5 and 7-9 exhibited strong antibacterial activities in vitro against five plant pathogens, with minimum inhibitory concentration values of 0.78-100 µg/mL.