Absorption of bioactive compounds from steamed broccoli and their effect on plasma glutathione S-transferase activity

Abstract

Cruciferous vegetables are characterized by high amounts of glucosinolates (GLSs) that are hydrolysed to isothiocyanates (ITCs) and other phytochemicals. The aim of the study was to verify the effect of broccoli intake on plasma levels of carotenoids, vitamins and ITCs and on glutathione S-transferase (GST) activity. Twenty healthy subjects, characterized for GSTM1 and GSTT1 genotype, participated in a cross-over intervention study (broccoli diet versus cruciferous-free diet). Subjects consumed a daily portion of broccoli (10 days, 200 g) providing glucosinolates (200 micromol non-indolyl ITCs evaluated by cyclocondensation reaction after myrosinase treatment), vitamin C (about 100 mg) and carotenoids (about 5 mg lutein and beta-carotene). An increase of folate, carotenoids and ITC plasma concentrations was found. The increase of plasma ITC concentration was independent of the GST genotype. Broccoli intervention did not affect plasma GST activity. Broccoli is a bioavailable source of diverse compounds whose effects on endogenous defence systems deserve further investigation.

Dietary Broccoli Sprouts Protect Against Myocardial Oxidative Damage and Cell Death During Ischemia-Reperfusion

“…In addition to sulforaphane, broccoli sprouts provide a variety of phytochemicals that may have contributed to the protection [14][15][16][17][18][19][20][21][22][23][24][25][26][27][28][29]. The dose of broccoli sprouts used herein (equivalent to 80-100 g fresh/day for humans) is achievable in a regular diet, posing a feasible dietary intervention against myocardial oxidative stress and ischemia-reperfusion injury.…”

“…In particular, broccoli and broccoli sprouts are rich in seleno compounds such as Se-methyl selenocysteine [16][17][18][19], carotenoids [20][21][22][23][24], tocopherols [23,24] and polyphenols [24][25][26][27]. Selenium [17,28] and polyphenols [24,29] have previously been implicated in antioxidant effects of broccoli.…”

“…Selenium [17,28] and polyphenols [24,29] have previously been implicated in antioxidant effects of broccoli. In some studies, antioxidant or other effects of broccoli are seen in the absence of effects on phase 2 enzymes [22,28,[30][31][32]. While mature broccoli has received much attention, very few studies have examined broccoli sprouts.…”

Functional Foods: From Theory to Practice

“…The results obtained (figure 1) demon- [19] strated that the regular consumption of broccoli (200 g for 10 days) was able to reduce significantly H 2 O 2 -induced DNA damage, thus increasing lymphocyte capacity to protect against oxidative DNA damage, in both smokers and non smokers. Moreover, broccoli intake was able to double ITC concentrations in plasma, but also to increase lutein, bcarotene and folate plasma concentrations (table 3) [33].…”

“…mean ( SD) plasma lutein, b-carotene, isothiocyanate and folate concentrations in all subjects (n=20), before and after each period of diet[33] a significantly different from each other point of the same row, p< 0.01; b significantly different from each other point of the same row, p<0.005; c significantly different from each other point of the same row, p<0.05Figure 1. Effect of 10 days broccoli consumption in smokers and nonsmokers on H 2 O 2 -induced DNA damage expressed as % variation [i.e.…”