Variation of hypericins in Hypericum triquetrifolium Turra growing in different locations of Turkey during plant growth.

The principle medicinal secondary metabolites present in Hypericum species are thought to be naphthodianthrones hypericin and pseudohypericin. The present study was conducted to determine ontogenetic and morphogenetic variations of hypericin and pseudohypericin contents in Hypericum triquetrifolium growing in two sites located in Northern Turkey. Plants were harvested at vegetative, flowering and fructification stages. Plants were dissected into stem, leaf and reproductive tissues at the time of harvest, dried separately and assayed for hypericin and pseudohypericin contents by high-performance liquid chromatography. The hypericin and pseudohypericin concentrations in the leaves and reproductive parts were highest at flowering and fructification, whereas the stem contents of these compounds decreased with advancing plant growth in both sites. The leaves contained higher concentrations of both naphthodianthrones than the stems or reproductive parts of H. triquetrifolium.