XVI International Botanical Congess

Hypericum perforatum L., St. John's Wort, an herbaceous perennial in the Hypericaceae, has been widely used on the general market for the herbal treatment of depression, and some of its constituents may also be useful as antiviral treatments. Analysis of Hypericum samples has become important since hypericins have been used as the measure of extract potency. We describe a new method for the analysis of hypericins from crude extracts using HPLC. Hypericin and related compounds were separated in 15 minutes using a simple isocratic elution method on a modified phenyl column. We also report on the photoconversion of protohypericins to hypericins, as well as the stability of hypericin and pseudohypericin as a function of light, time, and storage conditions.