Evaluation of Direct Mutagenesis in some of Natural Food Colors Using Ames Test

Nowadays, colors are widely used in various food industries, including sweets, confectionery, ice cream, beverages, and so on. Colors can have asthma-like complications, hyperactivity in children and cancers. Therefore, the aim of this study was to evaluate the direct mutagenic effect of several types of natural colors via Ames method.
After preparation of 6 natural colors from three different brands, their direct mutagenesis was investigated by Ames test. In this test, the strains of Salmonella typhimurium TA98 and TA100, carrying the selective mutation in His-Hiscoprotein Histidine, were cultured on glucose culture medium at least in the presence of color samples, and only the bacteria that had His mutation were colonized.
Direct mutagenicity of the food colors was measured by counting colonies in the plates containing edible color and comparing it with negative controls. The results showed that the number of referent colonies in plates containing cherry red and golden yellow for company B for both strains and the dark brown color of company B and C, and orange color for TA100 and TA98 strains in some concentrations were more than twice comparing the negative control plates and had direct mutagenic effects. The dark green and light green colors of the A, B, C, and golden yellow for companies A, C and cherry red and orange for companies C did not show direct mutagenic activity.
Based on these results, some of the studied colors, despite being declared natural, showed direct mutagenic activity.