[In vitro antibacterial activity of a halogenated derivative of D-alanine]

The "in vitro" effect of beta-chloro-D-alanine, a drug that inhibits cell-wall synthesis, was studied. We used some strains of microorganisms, mainly Gram-negative and resistant to antibiotics with the same mechanism of action. MIC and MBC values obtained show a poor efficacy of this drug. Therefore we studied the association of beta-chloro-D-alanine with ampicillin and fosfomycin. The evaluation of the results, determined by means of a graphic and a mathematical method, shows a good synergistic effect with both associations. Synergism is more marked with ampicillin.