Cytotoxic activity of Bulgarian Linum species

As part of our ongoing program on the investigation of lignans and their cytotoxic activity in Bulgarian Linum species, extracts of the aerial parts of L. tauricum ssp. linearifolium and L. elegans both endemic in the Balkan area were examined. The aryltetralin lignan 6-methoxypodophyllotoxin (MPTOX) is the main lignan in the extract from L. elegans with about 2 mg/g dry weight. Podophyllotoxin (PTOX) is the main lignan in the extract from L. tauricum ssp. lineraifolium with about 8 mg/g dry weight. The cytotoxicity of the extracts from both species was measured using the MTT–dye assay on human leukemic cell lines. Both showed moderate cytotoxic activity.