Effect of herbicide stress on the content of tyramine and its metabolites in Japanese radish sprouts (Raphanus sativus)

Japanese radish Daikon (Raphanus sativus) sprouts were exposed, under the model plant growing conditions, to herbicide stress induced by triketone herbicides (mesotrione and sulcotrione) as well as degradation products (4-methylsulfonyl-2-nitrobenzoic acid, amino-4-(methylsulfonyl)benzoic acid, 2-chloro-4-mesylbenzoic acid and cyclohexane-1,3-dione). Changes in the content of selected l -tyrosine metabolites (dopamine, tyramine, normetanephrine) and catecholamine synthesis cofactors (water-soluble vitamins) were monitored in plant tissues using high-performance liquid chromatography. Normetanephrine content increased up to 0.13 mg per gram of sprouts, 1500-fold higher than in the control sample. Tyramine and dopamine content increased by 50 % and 100 %, respectively. These changes corresponded with changes in the content of B3 and B9 vitamins. It has been proved that contact of the plant with this group of herbicides and theirs degradation products leads to a disturbance in the l -tyrosine metabolism. Consequently, this also leads to significant changes in the quality of foods of plant origin.