Secondary Metabolites in Flax Root Extracts at Various Stages of Maturity and Effects on Proliferation and Cytotoxicity in Oestrogen-Receptor-Positive Breast Cancer

Flax contains large amounts of hormone-like compounds, especially lignans. These so-called phy-toestrogens are thought to inhibit the cell growth of hormone-sensitive cancers. Hence, we ana-lysed the influence of flax root extracts at various stages of maturity on the proliferation and cy-totoxicity in oestrogen-receptor-positive breast cancer cells (MCF7) in vitro. Flax root extracts were prepared by using lignan extraction. The extracted compounds were analysed by Pyroly-sis-Field Ionisation Mass Spectrometry. Various extract concentrations were applied to the cells to test for proliferation (BrdU test) and cytotoxicity (LDH test). A significantly higher inhibition of cell proliferation was observed with an extract made from 9-week-old flax roots in comparison with that of 3- and 6-week-old roots. Older roots contained more lignans and other phenolic sub-stances than younger roots. The maturity grade of plants or their various parts is thus important for the production and concentration of secondary metabolites and leads to different biologica