Submitted to: Economic Botany
Publication Type: Peer Reviewed Journal
Publication Acceptance Date: November 30, 2000
Publication Date: N/A
Interpretive Summary: Hypericum perforatum, also known as St. John's wort, has become a popular herbal treatment of depression, and its active constituents are also known to be potent photoactive agents for use in antiviral therapy. Our study focused on analyzing the chemical composition of hypericins from wild populations of Hypericum perforatum collected in the Pacific Northwest in areas where wildcrafters collect material for sale to the U.S. herbal industry. It is not well documented whether genetic, physiological, or environmental influences can affect hypericin yields. We found significant differences in concentrations of hypericins among the eight sites and found indications of both genetic and environmental influences on hypericin yields.
Representatives from eight wild populations of Hypericum perforatum L. were collected from Montana and Northern California at flowering, and subsequently were analyzed for hypericin and pseudohypericin using HPLC analysis. Total plant yields in these wild populations were from 0.0003 to 0.1250% DW hypericin and 0.0019 - 0.8458% DW pseudohypericin. In general, hypericin concentrations were highest in the plant's reproductive tissues, followed by leaf and stem tissues, respectively. Hypericin and pseudohypericin concentrations were positively correlated in all samples, although the relative ratio of hypericin to pseudohypericin varied with site location.