title: Phytotoxic dioxolanone-type secondary metabolites from Guignardia bidwellii.
abstract: Phenguignardic acid was recently described as a phytotoxic secondary metabolite from submerged cultures of the grape black rot fungus Guignardia bidwellii. Since the production rate of this natural product in submerged culture is very low, fermentation optimisation was carried out. The optimisation of cultivation conditions led to the identification of seven secondary metabolites, structurally related to guignardic acid, a known secondary metabolite from Guignardia species containing a dioxolanone moiety. All metabolites presented here have not been described to date and are presumably biosynthesised via deamination products of amino acids, such as phenylalanine, valine, tyrosine, and alanine. Four of the seven compounds showed phytotoxic activity. Based on the structures determined by NMR spectroscopy a preliminary structure activity relationship indicated a free carboxyl group as presumably required for the phytotoxic activity.
authors: Institute of Biotechnology and Drug Research, Erwin-Schrödinger-Strasse 56, D-67663 Kaiserslautern, Germany. buckel@ibwf.de
authors: Iris
authors: I
authors: Buckel
authors: Daniel
authors: D
authors: Molitor
authors: Johannes C
authors: JC
authors: Liermann
authors: Louis P
authors: LP
authors: Sandjo
authors: Beate
authors: B
authors: Berkelmann-Löhnertz
authors: Till
authors: T
authors: Opatz
authors: Eckhard
authors: E
authors: Thines
mesh_terms: D001203:Ascomycota / Q000254:growth & development / Q000378:metabolism*; D004148:Dioxolanes / Q000737:chemistry / Q000302:isolation & purification / Q000378:metabolism* / Q000633:toxicity*; D005285:Fermentation; D006863:Hydrogen-Ion Concentration; D013696:Temperature; D027843:Vitis / Q000187:drug effects
chemical_list: D004148:Dioxolanes; C575777:phenguignardic acid