Evaluation of the inhibition of mercury absorption by vegetable juices using a red sea bream intestine model

Abstract

The ability of vegetables to inhibit methylmercury absorption was verified, with the aim of lowering the mercury level in cultured fish. Vegetable juice was obtained from 17 varieties of commercial vegetables. A test solution containing 1 μg/g methylmercury, 10% vegetable juice, and 90% physiological saline (v/v) was introduced into the intestinal tract of red sea bream, and the mercury absorption rate was measured. A significant inhibitory effect was observed for green pepper, burdock, and red shiso, mainly in the fraction with a molecular weight >3 kDa. Frozen storage for one month did not affect the inhibitory effect of green pepper; however, the inhibitory effect of frozen burdock and red shiso were destroyed after one week and one month, respectively. During one month of storage in frozen conditions, the inhibitory effect of green pepper was observed in fractions larger than 100 kDa. Molecular weight distribution of the effective fraction varied among the vegetables.