Urinary excretion of mutagens and the effects of sorbic acid on the lipid peroxide level in the mice fed on a 15% sorbic acid diet.

The urine of the mice fed on a 15% sorbic acid diet was treated with or without beta-glucuronidase and was fractionated by XAD-2 column chromatography. The non-polar urine fraction was slightly mutagenic towards TA 98 when metabolically activated, but not towards TA 100. From the comparison of thin-layer chromatograms between the intestinal and urinary samples, it was suggested that a part of the mutagens produced in the intestine was excreted in the urine. As for the lipid peroxidation, the levels of lipid peroxide in the liver of the mice fed on a 15% sorbic acid diet were lower than those in the control over the feeding period of 15 months. Moreover, there was a correlation between the concentration of sorbic acid (X) in the diet and the lipid peroxide level (Y) in mice fed on potassium sorbate diets, obeying the linear equation, Y=-8.39X+ 341 (p less than 0.01). However, the lipid peroxide levels of 15% sorbic acid group did not fit with the above equation, and was higher than those of 20.1% potassium sorbate group, which was equivalent to 15% sorbic acid group in respect of sorbic acid concentration. Accordingly, the difference of lipid peroxide levels between the two groups (15% sorbic acid and 20.1% potassium sorbate group) might reflect productive difference of the mutagens.