evaluation of cytotoxic effects of aqueous - methanolic saffron extract on vero, hela and hep2 cell lines using mtt assay method

background and objective: in addition to the use of chemicals in food, pharmaceutical, cosmetic and hygiene industries, use of herbal and natural compounds have also increased. it seems natural ingredients compared with the chemical components show less side effects, such as mutagenicity and carcinogenesis however, their use can also be associated with side effects and toxicity. some significant medicinal effects of saffron have been proven, which reveals the necessity to investigate the toxicity of the plant. this study aimed to evaluates the cytotoxic effects of saffron on cell lines vero, hela, and hep2 using mtt assay method. material and method: firstly the stigma of saffron was extracted by methanol: water 80:20 using maceration method. cytotoxic effects of different dilutions of saffron extract on vero normal cell lines and hela and hep2 cancerous cell lines was investigated using mtt assay method in a 96 well microplate. reading optical density (od) was done by microplate reader apparatus and ic50 (inhibition concentration 50%) was calculated for each cell line. results: aqueous - methanolic saffron extract on cell lines vero, hela, and hep2, showed ic50 equal 162, 653 and 208 μg/ml respectively. conclusion: saffron has a toxic effect on normal vero cell line. therefore, must be cautious to not to use it in food and as herbal medicine in high concentrations. also the extract of this plant revealed toxic effects on two cancerous cell lines, hepa2 and hela. however, its toxicity, especially on hela cancerous cell line was lower than the vero normal cell line.