Broccoli isothiocyanate content and in vitro availability according to variety and origin

Abstract

Broccoli is considered one of the healthiest vegetables due to its high content of beneficial biologically active compounds, i.e. the breakdown products of glucosinolates (GLSs), the isothiocyanates (ITCs). The aim of this work was to characterize the production of ITCs (sulforaphane and iberin and related metabolites) from different sources of GLSs by means of comparison between different broccoli cultivars and commercial samples in terms of their composition and in vitro bioavailability. Differences in the major intact GLSs were observed between the different experimental and commercial samples, showing lower concentrations of GLSs in the latter. The simulation of digestion reduced the concentration of the parent phytochemicals (GLSs), producing via hydrolysis the biologically active ITCs. The commercial samples showed lower levels of ITCs than the experimental broccoli cultivars. Measurement of GLSs by UPLCQqQ-MS/MS allowed for exact quantification of these compounds, particularly ITCs, which will help in future cancer chemoprevention studies.