Induction of hypericins in Hypericum perforatum in response to chromium

Seedlings of Hypericum perforatum were grown with 0.01 and 0.1mMof chromium added to the nutrient media. A treatment with 0.01 mM Cr(VI) for seven days resulted in an increased production of protopseudohypericin (+135%), hypericin (+38%) and pseudohypericin (+5%). Treatment with 0.1 mM Cr(VI) for two days also caused an increase of protopseudohypericin (+167%), hypericin (25%) and pseudohypericin (+5%). The greatest effect of chromium treatment was observed at a concentration of 0.1 mM for seven days: protopseudohypericin increased +404% and pseudohypericin to +379%. Hypericin was not affected by this treatment. © 2006 Elsevier B.V. All rights reserved. Keywords: Hypericum perforatum; Chromium; Hypericin;