title: pH modulation of zopfiellin antifungal activity to Colletotrichum and Botrytis.
abstract: Zopfiellin, a novel cyclooctanoid natural product isolated from Zopfiella curvata No. 37-3, was evaluated in a 96-well microtiter assay for fungicidal activity against Botrytis cinerea, Colletotrichum acutatum, Colletotrichum fragariae, Colletotrichum gloeosporioides, and Fusarium oxysporum. Zopfiellin exhibited pH-dependent activity, with the most mycelial growth inhibition demonstrated at pH 5.0. Mass spectrometry and nuclear magnetic resonance spectroscopy studies indicated that zopfiellin undergoes structural changes with changes in pH. At pH 5.0, zopfiellin showed the greatest activity against B. cinerea (IC(80) = 10 microM), C. gloeosporioides (IC(80) = 10 microM), and C. fragariae (IC(80) = 10 microM) and intermediate activity against C. acutatum (IC(80) = 30 microM), and was not active against F. oxysporum (IC(80) > 100 microM).
authors.affiliation: Shiraoka Research Station of Biological Science, Nissan Chemical Industries, Ltd., 1470 Shiraoka, Minamisaitama, Saitama 349-0294, Japan.
authors.forename: Mitsugu
authors.initials: M
authors.lastname: Futagawa
authors.forename: Agnes M
authors.initials: AM
authors.lastname: Rimando
authors.forename: Mario R
authors.initials: MR
authors.lastname: Tellez
authors.forename: David E
authors.initials: DE
authors.lastname: Wedge
mesh_terms: D001203:Ascomycota / Q000737:chemistry*; D020171:Botrytis / Q000187:drug effects*; D002851:Chromatography, High Pressure Liquid; D020231:Colletotrichum / Q000187:drug effects*; D034242:Cyclooctanes / Q000737:chemistry / Q000302:isolation & purification / Q000494:pharmacology*; D005659:Fungicides, Industrial / Q000737:chemistry / Q000302:isolation & purification / Q000494:pharmacology*; D005670:Fusarium / Q000187:drug effects; D006863:Hydrogen-Ion Concentration; D009682:Magnetic Resonance Spectroscopy; D013058:Mass Spectrometry; D010935:Plant Diseases / Q000382:microbiology
chemical_list: D034242:Cyclooctanes; D005659:Fungicides, Industrial; C470145:zopfiellin