Figure 3From: Thermal degradation of natural dyes and their analysis using HPLC-DAD-MSHPLC-DAD chromatograms of the mixed dye solution after 1 ~ 9 days of thermal degradation treatment. Numbers in the chromatograms indicate; 1 berberine, 2 palmatine, 3 alizarin, 4 purpurin, 5 indigotin, 6 indirubin.Back to article page