Bioaccessibility of glucosinolates, isothiocyanates and inorganic micronutrients in cruciferous vegetables through INFOGEST static in vitro digestion model

Abstract

Green tissues and seeds from cruciferous vegetables growing in conventional and ecological conditions (Brassica carinata; Brassica rapa; Eruca vesicaria and Sinapis alba) were analyzed to determine their contents of glucosinolates, isotihiocyanates (ITCs) and inorganic micronutrients (Ca, Cr, Cu, Fe, Mn, Ni, Se and Zn), and the bioaccessibility of these compounds. Regarding total contents and bioaccessibility values of these compounds, no clear difference was found between the organic and conventional systems. Glucosinolates bioaccessibility present in green tissues were high, with values around 60–78%. In additon, it was quantified in bioaccessible fraction ITCs concentrations such as Allyl – ITC; 3 – Buten – 1 – yl – ITC and 4 – Penten – 1 – yl – ITC. Trace elements bioaccessibility in green tissues was also high for Ca (2.26–7.66 mg/g), Cu (0.60–2.78 µg/g), Se (9.93–74.71 µg/Kg) and Zn (12.98–20.15 µg/g). By contrast, the bioaccessibility of glucosinolates and trace elements in cruciferous seeds was extremely low. With the exception of Cu, these bioaccessibility percentages did not exceed 1% in most cases.