Use of lipids to potentiate the antibacterial activity of aminoglycosides.

Linolenyl alcohol has been shown to inhibit the in vitro growth of several species of gram-positive bacteria. Since the double bonds in linolenyl alcohol could undergo autooxidation, the antimicrobial activities of saturated primary alcohols of similar molecular sizes against Streptococcus mutans BHT were evaluated. Tridecan-1-ol was identified as the most active compound, eliciting a bacteriostatic effect at concentrations at which growth occurred in the presence of other saturated alcohols or linolenyl alcohol. Evidence is also presented that the combined use of tridecan-1-ol and gentamicin sulfate produces a synergistic effect that is bactericidal to S. mutans BHT. A similar bactericidal response was observed when tridecan-1-ol was combined with other aminoglycosides or tested alone against other strains of S. mutans.