Secondarv Metabolites Of Two Fungi With Antagonistic Activity To Wheat Fusarium Graminearum

Fusarium Head Blight (FHB) disease is the most diffuse wheat ear disease throughout the world, and Fusarium graminearum is one of the most important causal agents of the fungal disease. F. graminearum not only reduces yield and seed quality but also constitutes a risk to public or animal health owing to its ability to contaminate grains with mycotoxins. Chemical fungicides, like triazoles, are the main measure to control the impact of the F. graminearum infection, Nevertheless, the problems of fungicide-resistance and environmental pollution have arisen. Consequently, there is a clear need to discover new biomolecules to replace currently available fungicides. Marine microbes are capable of producing secondary metabolites with novel structures and potent bioactivities to be potential antibiotics in agricuture. In this study, we aim to discover some new antibiotics against F. graminearum from marine microorganism.Two antagonistic fungi against F. graminearum, Capnodium sp. SZ-F22 and Trichoderma sp. NB-F14, were isolated and screened from mangrove-plants and marine sediment through dilute and spread plate method and flat confrontation method. We further purified and identified 19 compounds (1-19) from the broth extract of the two fungi, compound 3 was a new eremophilane sesquiterpene, and compound 4 was identified as a single natural product for the first time. All compounds did not show expected antifungal activity against F. graminearum.