in vitro evaluation of capsaicin inhibitory effects on zonula occludens toxin in vibrio cholerae atcc14035 strain

background: cholera is a potentially epidemic and life-threatening secretory diarrhoea characterized by voluminous watery stools, often accompanied by vomiting, and resulting in hypovolemic shock and acidosis. it is caused by certain strains of the species vibrio cholerae which can also cause mild or in apparent infections. the aim of this study is the evaluation of capsaicin, as a potential inhibitor of zonula occludens toxin production in v. cholerae atcc 14035. materials and methods: mic of capsaicin was determined by broth microdilution method according to clsi guidelines. the zot gene expression level were analysed using real-time rt–pcr technique. results: results from mic test showed that 100 μg ml−1of capsaicin was the highest concentration that did not affect the bacterial growth however, zonula occludens toxin (zot) gene expression of the tested strain was significantly inhibited by capsaicin in a dose-dependent manner at sub-bacteriocidal concentrations. the reca gene did not show any significant difference in its expression with or without capsaicin. conclusion: capsaicin is one of the active compounds of red chili that can drastically suppress zot gene expression and shows promising inhibitory effect against v. cholerae zot production. thus, routine intake of red chilli, which is easily available and inexpensive, may be an alternative approach to prevent and control symptoms of cholera.