Antibacterial composition comprising triethyl citrate and a peptide consisting of 15 amino acids of the sequence FAKALKALLKALKAL-NH2, in which F is phenylalanine, A is alanine, K is lysine, and L is leucine.Composición antibacteriana que comprende citrato de trietilo y un péptido que consiste en 15 aminoácidos de secuencia FAKALKALLKALKAL-NH2, en la que F es fenilalanina, A es alanina, K es lisina, y L es leucina.