Secondary metabolites in Hypericum species and their distribution in different plant parts

The genus Hypericum (Hypericaceae) has attracted remarkable scientific interest as its members accumulate significant amounts of various bioactive compounds. In the current study, we investigated accumulation of several bioactive compounds in various parts of Hypericum hircinum L. subsp. majus (Ainton) N. Robson, H. pallens Banks et Sol., H. russeggeri (Fenzl) R. Keller and H. lanuginosum Lam. The plant materials were harvested at flowering, dissected into different tissues and subsequently subjected to high performance liquid chromatography (HPLC) analyses. Accumulation level of the investigated compounds varied greatly depending on species and plant parts. Among different plant tissues, flowers were found to be superior to leaves with respect to accumulation of the chemicals tested except for neochlorogenic, caffeic and 2,4-dihydroxybenzoic acids which were accumulated mainly in leaves. H. hircinum did not produce quercitrin or avicularin, H. lanuginosum did not accumulate hyperforins and caffeic acid, rutin was detected only in H. pallens. For the first time, chemical profiles of these Turkish species of Hypericum were reported and the results are discussed from a phytochemical point of view. The present data could be helpful in selecting the future targets for phytochemical and biological studies on Hypericum genus as well as enriching our current knowledge about Hypericum chemistry.