Hypericin and pseudohypericin in some Hypericum species.

Hypericin and pseudohypericin were found in 27 of the 36 evaluated species from Hypericum L., belonging to 17 sections of the genus. Pseudohypericin is reported by us in 15 taxa for the first time. Most of the species contained both components and the amount of pseudohypericin usually exceeded that of hypericin. In H. hirsutum and H. empetrifolium only hypericin was found, whereas H. formosissimum yielded pseudohypericin only. The total content of hypericins varied widely from 0.009% in H. empetrifolium to 0.512% in H. boissieri and the largest amounts were established in taxa of sections Drosocarpium, Hypericum and Thasia. The distribution of hypericin and pseudohypericin in Hypericum species has an important taxonomic value for infrageneric classification of the genus. These components were not found in the primitive sections Ascyreia, Androsaemum, Inodora, Roscyna, Bupleuroides and Spachium but occur widely in Hypericum, Adenosepalum and the sections from Olympia group. Although the genera of subfamily Hypericoideae are characterized by the presence of anthrone derivatives, condensed anthrones such as hypericin and pseudohypericin have not been found in these genera and the remaining subfamilies of the Guttiferae.