Biological activity of a heptaketide metabolite from Pleiochaeta setosa.
An uncommon heptaketide metabolite, setosol (2,8-dimethyl-4 methoxy-6,10,11-trihydroxy-benzo-oxaonin), was isolated from a liquid culture filtrate of the fungus Pleiochaeta setosa. The biological activity of the molecule was studied by using 12 microbial strains consisting of three bacteria, three yeasts and six fungi. The level of activity was compared with those of known antibiotics and antifungal agents. The metabolite exhibited antifungal and antibiotic activity against Drechslera oryzae, Gerlachia oryzae, Pyricularia oryzae, Cryptococcus neoformans, and Staphylococcus aureus. The acetylated derivative of setosol did not inhibit the growth of any of the target pathogens. Phytotoxicity studies on whole lupine leaves show that setosol is implicated in the pathogenesis of the brown spot disease of lupines since artificial inoculation of the leaves with the metabolite provoked lesions similar to the characteristic brown spots and lesions on lupine leaves infected by the fungus.
Okeke
B
B
Laborätoire de Botanique, Cryptogamie, Biologie Cellulaire et Génétique, UFR de Pharmacie, Université Joseph Fourier, Meylan, France.
Seigle-Murandi
F
F
Steiman
R
R
D000107:Acetylation; D000900:Anti-Bacterial Agents / Q000494:pharmacology*; D000935:Antifungal Agents / Q000494:pharmacology*; D001236:Aspergillus oryzae / Q000187:drug effects; D001419:Bacteria / Q000187:drug effects*; D002176:Candida albicans / Q000187:drug effects; D003455:Cryptococcus neoformans / Q000187:drug effects; D004926:Escherichia coli / Q000187:drug effects; D005658:Fungi / Q000187:drug effects*; D005670:Fusarium / Q000187:drug effects; D006571:Heterocyclic Compounds / Q000302:isolation & purification / Q000494:pharmacology; D003904:Mitosporic Fungi / Q000378:metabolism*; D010935:Plant Diseases; D011550:Pseudomonas aeruginosa / Q000187:drug effects; D013211:Staphylococcus aureus / Q000187:drug effects; D013329:Structure-Activity Relationship
D000900:Anti-Bacterial Agents; D000935:Antifungal Agents; D006571:Heterocyclic Compounds; C092938:setosol