Validamycin A

Validamycin A is an antifungal agent used to protect rice plants against sheath blight caused by the pathogenic fungus, R. solani, due to its ability to inhibit trehalase, a trehalose-hydrolizing enzyme (Ki = 1.9 nM; IC50 = 0.7 μM). It is also effective against the growth and sporulation of R. cerealis, F. culmorum, and other fungi. Validamycin A also demonstrates antiviral activity against fungal plant pathogens, including Pellicularia sasakii and Rhizoctonia solani, but does not appear to be fungicidal in these cases.