The Effect of Dioctyl Sodium Sulphosuccinate on Tartrazine Azo reduction by Intestinal Bacteria

1. Washed whole-cell suspensions of Proteus vulgaris and micro-organisms from rat faeces, reductively cleave the azo bond of the food dye tartrazine under anaerobic conditions. 2. Dioctyl sodium sulphosuccinate, a common faecal softening laxative, when added to incubations in vitro at concentrations greater than 0 005%, increases tartrazine azo reduction in P. vulgaris whole-cell suspensions. 3. By contrast, concentrations of dioctyl sodium sulphosuccinate greater than 0 005% when added to incubations in vitro of rat faecal preparations, resulted in an inhibition of tartrazine azo reduction.