Concentrations of flavonoid glycosides and naphthodianthrones in Hypericum samples. The compounds are: rutin (Rn), hyperoside (He), isoquercitrin (In), quercitrin (Qn), pseudohypericin (Pn), and hypericin (Hn). Values are given in μmol/g FW and as means±SD, N=3 technical replicates for each plant sample. From 10 H. perforatum and 6 H. hirsutum branches having been cut in the field and maintained at the laboratory, leaves and inflorescences were taken from them after 1, 8, and 15 d (i.e., dark grey, light grey, and white bars, respectively, for each compound), and from one potted plant of each species (black bar)