ABSTRACT
Novel autoregulatory metabolites, arthrosporols A-C (1-3), involved in regulating the morphological switch in fungi, were purified and characterized from the carnivorous fungus Arthrobotrys oligospora. These compounds possess a novel hybrid carbon skeleton consisting of an epoxy-cyclohexenol combined with a rare monocyclic sesquiterpenol substructure. This is the first report of a monocyclic sesquiterpenol of this type of fungal origin. Compounds 1-3 displayed significant inhibitory activities toward the formation of conidiophores, while compounds 1 and 3 showed the opposite effects on the formation of a two-dimensional network with increasing rates of 40-90% and inhibiting rates of 30-90%, respectively.
Subject(s)
Ascomycota/chemistry , Cyclohexanols/isolation & purification , Sesquiterpenes/isolation & purification , China , Cyclohexanols/chemistry , Molecular Structure , Nuclear Magnetic Resonance, Biomolecular , Sesquiterpenes/chemistryABSTRACT
Arthrobotrys oligospora is a carnivorous fungus that can use mycelia trapping devices to capture their prey. Three novel oligosporons, named arthrobotrisins A-C (1-3), were isolated from A. oligospora and identified by spectroscopic analysis in combination with X-ray diffraction. This is the first time that the relative configuration of naturally occurring oligosporon metabolites has been fully determined. Compound 3 exhibited specific antibacterial activities.
Subject(s)
Anti-Bacterial Agents/isolation & purification , Antinematodal Agents/isolation & purification , Epoxy Compounds/isolation & purification , Mitosporic Fungi/chemistry , Nematoda/drug effects , Animals , Anti-Bacterial Agents/chemistry , Anti-Bacterial Agents/pharmacology , Antinematodal Agents/chemistry , Antinematodal Agents/pharmacology , Crystallography, X-Ray , Epoxy Compounds/chemistry , Epoxy Compounds/pharmacology , Molecular Conformation , Molecular StructureABSTRACT
Chemical investigation of one fungal strain P. chlamydosporia YMF 1.00613 isolated from root knots of tobacco infected by Meloidogyne incognita led to the isolation and identification of four aurovertin-type metabolites, which include a new compound, aurovertin I (A1), and three known metabolites, aurovertins E, F and D (A2-A4). Their structures were established by spectroscopic studies such as 1D- and 2D-NMR and MS analysis. Aurovertin I (A1) is the first natural product with an aurovertin skeleton with one less carbon. Compounds A3 and A4 showed the toxicity to the worms of the free-living nematode Panagrellus redivevus with the LC(50) values 88.6 and 41.7 microg/mL at 48 h, respectively. All four aurovertins did not show obvious inhibitory effects on egg hatch of root knot nematode Meloidogyne incognita. The results suggested that the aurovertin-type metabolites produced by P. chlamydosporia might be one of the pathogenic factors involved in the suppression of nematodes.
