Effect of different surfactants on the efficacy of triclosan against bacillus subtilis

Abstract

Drugs designed for oral dosage forms have major challenge of their bioavailability. Any drug must be present in the form of an aqueous solution at the site of absorption. Triclosan, an effective antibacterial agent, inhibits an essential enzyme present in most of the bacteria (Fab I) thereby blocking their fatty acid biosynthesis. However, the molecule is poorly soluble in aqueous solutions. A study was carried out to understand the effect of six different surfactants on the IC50 value of triclosan against Bacillus Subtilis. Four of the six surfactants contained long alkyl or alkoxy chains namely, Tween-80, Tween-20, TritonX-100 and CTAB. The other two surfactants were carbohydrate and steroid based namely γ-cyclodextrin and sodiumdeoxycholate. Tween-80 and Tween-20 enhanced the growth of bacteria in presence of triclosan thereby inhibiting the effect of drug. TritonX-100 marginally inhibited the growth of bacteria around its CMC values there by suggesting it to be the best surfactant among six to dissolve triclosan. All other surfactants themselves inhibited the growth of bacteria and there by masked the effect of triclosan.