RESUMEN
Monogastric animals exhibit different biological responses to structurally diverse glucosinolates and their transformation products, depending on the dietary levels. The transformations of 2-hydroxyalkenyl and aromatic glucosinolates were examined in vitro under gastric conditions, ex vivo in ligated porcine stomachs and in vivo in a rat model. Intact glucosinolates were almost completely transformed in vitro within 1â¯h at pH 3 (73-88%) and at pH 5 (97-100%) upon addition of Fe2+ ranging from two-fold molar excess. Glucosinolate transformations reached 78-99% when incubated ex vivo in ligated porcine stomachs. Rat in vivo feeding trials showed major reductions (81-84%) in the intact glucosinolate contents upon passage through the gastrointestinal (GI) tract. Non-enzymatic transformations of glucosinolates occur in the stomach, where pH and the level of Fe2+ are primary determinants. This is the first study to show a complex formation between iron-progoitrin and iron-sinalbin, facilitating the transformation into nitriles and thionamides.
