Carpesium divaricatum Sieb. & Zucc. is a plant species rich in terpenoids of anti-inflammatory and cytotoxic activity, especially germacranolides of potential medicinal value. The present study describes in vitro multiplication of C. divaricatum, analysis of active constituents in the multiple shoots, and assessment of cytotoxic activities of extracts prepared from in vitro- and field-grown plants. The plant extracts were evaluated for cytotoxicity using two melanoma cell lines (HTB140 and A375); human keratinocytes (HaCaT); two colon cancer cell lines (Caco2 and HT29); human hepatocellular carcinoma cells (HepG2); two lines of prostate cancer cells (DU145 and PC3) and prostate epithelial cells (PNT2). Chemical compositions of the assayed extracts were analyzed by HPLC/DAD, in reference to isolated compounds. Maximum of 4.07 ± 1.61 shoots regenerated from a nodal explant of C. divaricatum, cultivated in a liquid MS medium supplemented with thidiazuron (1 μM). In vitro grown shoots and plantlets of C. divaricatum accumulated terpenoids that are known as active constituents of the intact plant. Cytotoxic activity of the extracts prepared from the in vitro cultured plants was like that demonstrated by the extracts prepared from field-grown plants and seemed to be more selective than cytotoxicities of the individual germacranolides.
Keywords: Carpesium; cytotoxicity; micropropagation; multiple shoots; plant tissue culture; sesquiterpene lactones; thymol derivatives.