Submitted to: Journal of Applied & Environmental Microbiology
Publication Type: Peer Reviewed Journal
Publication Acceptance Date: 9/4/1998
Publication Date: N/A
Interpretive Summary: Fungi that parasitize and kill other fungi offer a potential source of novel antifungal agents useful to agriculture and medicine. The fungus Humicola fuscoatra NRRL 22980 was isolated as a parasite of the important aflatoxin-producing fungus Aspergillus flavus that was buried for three years in a Georgia cornfield. When grown in laboratory culture H. fuscoatra produced antifungal agents, including a new monorden compound, that strongly inhibited the growth of Aspergillus. The strategy of selecting fungal parasites of Aspergillus as potential sources of antifungal antibiotics with activity against the same mold that causes aspergillosis in humans and poultry is unprecedented. These new compounds should be of interest to agricultual and pharmaceutical companies.
Technical Abstract: The mycoparasite Humicola fuscoatra NRRL 22980 was isolated from a sclerotium of Aspergillus flavus that had been buried in a corn field near Tifton, Georgia. When grown on autoclaved rice, this fungus produced the antifungal metabolites monorden, monocillin IV, and a new monorden analog which is identified. Each of these metabolites produced a clear zone of inhibition surrounding paper assay disks on agar plates seeded with conidia of A. flavus. Cerebrosides C and D, metabolites known to potentiate the activity of cell wall-active antibiotics, were separated from the ethyl acetate extract but were not inhibitory to A. flavus when tested as pure compounds. This is the first report of natural products from H. fuscoatra.