Title: New secondary metabolites from bioactive extracts of the fungus Armillaria tabescens Authors
|Herath, Bandara H.M.T. -|
|Jacob, Melissa -|
|Wilson, A. Dan -|
|Nanayakkara, Dhammika -|
Submitted to: Journal of Natural Products
Publication Type: Peer Reviewed Journal
Publication Acceptance Date: September 11, 2012
Publication Date: November 9, 2012
Citation: Herath, B., Jacob, M., Wilson, A., Abbas, H.K., Nanayakkara, D. 2012. New secondary metabolites from bioactive extracts of the fungus Armillaria tabescens. Journal of Natural Products. 27(17):1562-1568. Interpretive Summary: We discovered that extracts of a mushroom, Armillaria tabescens, produce compounds, 2 of which are new and are active against harmful bacteria and fungi. These natural products have potential to be developed into antibiotics to help humans and animals. They are active against harmful bacteria and fungi for human health such as Candida albicans (yeast infection), Escherichia coli, and Staphylococcus aureus, which also cause important illnesses. This research should benefit farmers as well because fungi and bacteria are a problem for crops.
Technical Abstract: Ethyl acetate extracts of Armillaria tabescens (strain JNB-OZ344) mycelium showed significant fungistatic and bacteristatic activities against several major human pathogens including Candida albicans, Cryptococcus neoformans, Escherichia coli and Mycobacterium intracellulare. Chemical analysis of these extracts led to the isolation and identification of four new compounds, emestrin-F (1), emestrin-G (2), 6-0-(4-O-methyl-ß-D-glucopyranosyl)-8-hydroxy-2,7-dimethyl-4H-benzopyran-4-one (3) and cephalosporolide-J (4) along with five other previously known compounds, emestrin (5), cephalosporolide-E (6), decarestrictine-C2 (7), ergosterol and brassicasterol. Structural elucidation of all compounds was carried out by NMR and MS analysis. Antimicrobial assays revealed that compounds 1 and 5 were responsible for the observed growth-inhibitory activities of the fungal extracts against the human pathogens tested.