Fig. 2. Sample HPLC-DAD chromatograms (k = 272 nm) of ITC-NAC conjugates formed as a result of derivatization of ITCs present in mixture of ITC standards (A), broccoli extract (B), white cabbage extract (C) or horseradish extract (D). The conjugation reaction was carried out for 60 min at 50 C for mixtures containing 0.1 M NAC, 0.1 M NaHCO3 in water and 0.5 mL of 0.5 mM of each ITC standard or 0.5 mL of plant extract in isopropanol. The numbers of peaks of detected ITC-NAC conjugates correspond to analytes listed in Table 2.