Each experimental unit contained 50 plants. For each cultivar, data were obtained on 10 different plants. For broccoli, plants were transplanted 40 days after sowing; plants had developed to the 4–6 leaf stage (5–10 mm plant diameter and 0.15 m plant height). For broccoli and collard green, the spacing between plants Selleckchem INCB024360 was 50 × 100 cm. Watercress, and rocket cultivations were planted with 20 × 25 cm and 20 × 15 cm spacing, respectively. During the experiment, mineral fertilizer treatment (120 g m−2) was applied two times (10 days before and 15 days after transplantation), and organic fertilizer (8 kg m−2 castor pomace) was applied at planting.

The regional climate is mesothermal, humid subtropical and dry during the winter. Irrigation was carried out twice a day. Broccoli (Brassica oleracea L. cv. Italic Ramoso Piracicaba) (Sakata Seed America®) was harvested 90 days after sowing; organic and conventionally grown plants were at the same physiological phase of maturation at the time of harvest. Plants were morphologically separated into inflorescence (I), leaves (L) and stalks (S). A portion of the broccoli was processed raw, and the other portion was treated at 100 °C for 5 min (cooked). The cooking procedure was carried out on the entire broccoli plant C59 wnt manufacturer (I + L + S), and

separate containers were used for organic and conventionally derived vegetables. Immediately thereafter, the broccoli samples were stored at to room temperature, dried with absorbent paper and separated into inflorescence, leaves and stalks, which was similar to the procedures for the raw material; samples were then frozen at −20 °C. Collard green leaves (B. oleracea L. cv. Manteiga Cabocla) (Sakata Seed America®) were harvested 80 days after sowing, and rocket (Eruca sativa L. cv. Folha Larga) (TopSeed®) and watercress (Nasturtium officinale R. Br. cv. Agrião d`Água) (Sakata Seed

America®) were harvested at 40 and 60 days after seed germination, respectively. The same procedures described above for broccoli were conducted on the other vegetables. All samples from were previously selected in agreement with the producers and according to cultivation procedures and thermal processing. The samples were washed with water, sanitized with acetic acid (1.201 g L−1) for 10 min and again washed with water. After drying, the samples were rapidly frozen by immersion in liquid nitrogen (SCRIO 22 container) and stored at −20 °C until use. The extraction of total glucosinolates was carried out on Brassicaceae vegetal material (raw and/or cooked) according to Kiddle et al. (2001) with minor modifications. Samples (3 g) were homogenized (n = 3, in triplicate for each vegetable and condition) in a porcelain mortar containing 5 mL of 70:30 MeOH (mL):water (mL) in the presence (+) or in the absence (−) of 1.49 g L−1 trifluoroacetic acid (TFA) (Sigma). Extracts were transferred to stoppered Erlenmeyer flasks and conditioned in a thermostatic bath under constant agitation.