Structural characterization of degradation products in various food dyes by HPLC DAD MS MS and evaluating their in vitro genotoxic potential by bacterial reverse mutation assay

Abstract

quotObjective: 1. Non-target screening of photodegradation products of selected azo dyes in commercial beverages. 2. To propose the structures of degradation products based on accurate mass data and elemental composition. 3. Analytical method validation and 4. In vitro mutagenicity evaluation of photodegradation products. newlineMethodology: After a thorough literature survey, three azo dyes were selected namely, Tartrazine (E102), Carmoisine (E122) and Ponceau 4R (E124). The stability of these dyes was evaluated by photodegradation studies both in standard model solutions and beverages. A high resolution UHPLC-Q-TOF mass spectrometer is used to identify the degradation products. Mutagenic potential of beverage containing dye before and after sunlight irradiation was studied by the Ames assay. newlineResults: The standard model solutions and beverages containing E102, E122 and E124 were exposed to natural sunlight. It was observed that dyes were decolourized rapidly in beverages when compared to standard model solutions. The degraded beverages containing dyes were then subjected to UHPLC-Q-TOF MS/MS analysis to identify and to characterize the degradation products. Photodegradation of E102, E122 and E124 in beverages has yielded six, four and six degradation species, respectively. Further, the mutagenic potential of beverages containing E102, E122 and E124 before and after sunlight irradiation was studied by the Ames assay using five bacterial strains. It was observed that photodegradation products of E122 and E124 in beverage were mutagenic in in vitro. newlineConclusion: The results indicated that photodegradation products of E122 and E124 are mutagenic, which need to be further evaluated in in vivo systems. In conclusion, the identification of degradation products must be performed in real solutions not in simple model solutions. Further, the beverages containing E102, E122 and E124 must be protected from direct sunlight to prevent photodegradation. newlinequot