Optimization and validation of analytical RP-HPLC methods for the quantification of glucosinolates and isothiocyanates in Nasturtium officinale R. Br and Brassica oleracea

Watercress contains a considerable amount of vitamins, minerals and secondary metabolites is used in food for its medicinal properties. These latter are mainly attributed to glucosinolates which precursors bioactive compounds such as isothiocyanates. Broccoli an edible vegetable the family Brassicaceae that rich vitamins metabolites. Because biological activity sulforaphane, broccoli became popular supplement. However, also glucosinolate progoitrin derivative goitrin, antithyroid compound goitrogen, can enlarge thyroid gland. To avoid these effects, daily intake goitrin limited 20 mg 5 mg. Since quality supplements watercress depends on content their derivatives, quantitative HPLC methods were developed validated conform ICH guidelines analyse glucosinolates, phenylethyl isothiocyanate goitrin. The linear ranges 0.084–0.418 μmol/mL(gluconasturtiin), 0.013–1.04 μmol/mL (phenylethyl isothiocyanate), 0.044–1.312 (glucotropaeolin) 0.0077–3.0965 (goitrin). precision with respect time concentration was acceptable. A recovery 99.2% 100.6% obtained