Evaluation of the Antimicrobial Effects of Several Isothiocyanates on Helicobacter pylori

Abstract

The antibacterial activity of sulforaphane [4-(methylsulfinyl)butyl isothiocyanate] has been previously described. We have analysed the activities of 12 isothiocyanates (ITC) including sulphoraphane on 25 strains of Helicobacter pylori using an agar dilution assay. In addition, bactericidal effects against H. pylori were determined for the 6 most active ITCs, both directly and against intracellular bacteria in cultured human epithelial (HEp-2) cells. The MIC₉₀ values for these ITCs ranged between 4 and 32 μg/mL and four of the most potent compounds exhibited bactericidal activity against both extra- and intracellular bacteria. Overall, our data indicate that ITCs have a potent antibacterial effect against H. pylori and these naturally occurring phytochemicals might have potential as novel therapeutic agents for H. pylori eradication.

Key words

Helicobacter pylori - isothiocyanate - time-to-kill assay - minimal inhibitory concentration

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