[Studies on coloring constituents in commercial madder color].

Two main coloring constituents in the commercial madder color were isolated and identified as ruberthric acid and lucidin-3-O-primeveroside. On quantitative analysis by high-performance liquid chromatography, the contents of ruberthric acid and lucidin-3-O-primeveroside in commercial madder color were determined 0.07% and 0.04%, respectively.