Figure 6.

Comparisons of the videodensitogram fingerprint profiles of STSs (1 μL, 50 mg/mL) from leaves and rhizomes of the same knotweed species (Japanese (A), Bohemian (B) and giant (C) knotweed) with the videodensitogram of standards (−)-epicatechin (EC; R_F = 0.82) and procyanidin B2 (B2; R_F = 0.63) (30 ng; dashed green line). The videodensitograms were obtained in absorption mode by image analysis of the HPTLC silica gel plates after the development with toluene–acetone–formic acid (3:6:1, v/v) and after the derivatization with DMACA detection reagent. The asterisks (*) in dicate peaks that are only present in the rhizomes of Japanese and Bohemian knotweed.