Antibacterial effects of enniatins J(1) and J(3) on pathogenic and lactic acid bacteria

Enniatins (ENs) are N-methylated cyclohexadepsipeptides, secondary metabolites produced by various species of the genus Fusarium. They are known to act as antifungal, antiyeast and antibacterial and to possess antiinsecticidal and phytotoxic properties. In this study we evaluated for the first time the antibiotic effect of pure fractions of EN J(1) and J(3) on several pathogenic strains and lactic acid bacteria. The ENs J(1) and J(3) were purified from the fermentation extract of Fusarium solani growth on solid medium of wheat kamut, using the technique of the low pressure liquid chromatography (LPLC) followed by a semipreparative liquid chromatography (LC). The purity and the structure of the isolated compound were confirmed by electrospray ionization-mass spectrometry study-linear ion trap (ESI-MS-LIT). The use of both chromatographic techniques have permitted to produce and purify 47mg of the En J(1) and 50mg of the EN J(3) with a mean purity of 98% completely characterized with the technique of the ESI-MS-LIT. Microbial bioassay analyses were carried out by incubation in MRSA and TSA for acid lactic and pathogenic bacteria, respectively during 24h at 37°C. None of the tested strains were inhibited by a 1ng dose of EN J(1) and J(3). These compounds were only not effective against Listeria monocytogenes, Pseudomonas aeruginosa and Salmonella enteric. This study highlight ENs J(1) and J(3) could be potentially effective antibacterial agents against several pathogenic and lactic acid bacteria.