Beauvericin is a depsipeptide with antibiotic and insecticidal effects belonging to the enniatin family. It was isolated from the fungus Beauveria bassiana, but is also produced by several other fungi, including several Fusarium species; it may therefore occur in grain contaminated with these fungi. Beauvericin is active against Gram-positive bacteria and mycobacteria, and is also capable of inducing programmed cell death in mammals. Chemically, beauvericin is a cyclic hexadepsipeptide with alternating methyl-phenylalanyl and hydroxy-iso-valeryl residues. Its ion-complexing capability allows beauvericin to transport alkaline earth metal and alkali metal ions across cell membranes. Beauvericin, a cyclic hexadepsipeptide with antibiotic properties, has been shown to reduce contraction force and to affect action potential parameters of guinea pig papillary muscles.