Figure 1: HPLC spectra for chemical constituents of milk thistle extract, silymarin, and silibinin (chemical structure) (a) and for isoflavones present in prepared soybean extract (b). The peaks of silymarin and silibinin were identified, as confirmed by the UV contour plot obtained by a photodiode-array detector (a). The peaks of daidzin, genistin, glycitin, daidzein, genistein, and glycitein were also identified (b).