Antimicrobial system which comprises a cationic surfactant, derived from the condensation of fatty acids and esterified dibasic amino acids, according to the following formula (I), where: X is Br, Cl or HSO.sub.4R.sub.1: is linear alkyl chain from an saturated fatty acid, or hydroxyacid from 8 to 14 atoms of carbon bonded to the .alpha.-amino acid group through amidic bond. R.sub.2 is a linear or branched alkyl chain from 1 to 18 carbon atoms or aromatic. R3: is Formula (II), where n can be from 0 to 4, and at least one antimicrobial agent characterised for its enhanced activity. ##STR00001##