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Cytotoxicity-guided fractionation of the MeOH extract of Helleborus lividus Aiton ex Curtis (Ranunculaceae) resulted in the isolation of five undescribed bufadienolide glycosides and two undescribed bufadienolides, along with three known compounds. Their structures were determined by detailed spectroscopic analysis and hydrolysis studies. The isolated compounds showed cytotoxicity against HL-60 human leukemia cells and A549 human lung adenocarcinoma cells, with IC50 values ranging from 2.20 ± 0.01 nM to 0.77 ± 0.01 μM. The undescribed compound 3β-[(O-β- d -glucopyranosyl-(1 → 4)-α- l -rhamnopyranosyl)oxy]-14β,16β-dihydroxy-5β-bufa-20,22-dienolide induced apoptosis in HL-60 cells via a mitochondria-dependent apoptotic pathway. The average IC50 values of bufadienolide monorhamnosides for HL-60 and A549 cells were 10–20 times lower than those for Na+/K+ ATPase, implying that they induce tumor cell death via a mechanism of action other than Na+/K+ ATPase inhibition.

For two years (2006 − 2007), seedlings and young plants of Helleborus lividus Aiton were grown in containers with a peat substrate, which was deacidified with calcium carbonate at the following doses: 2.5, 5.0, 7.5 and 10.0 g dm-3. The plants were divided into two groups in each variant of CaCO3 dosage, one fertilized with a solution of a lower (0.1%) and the other with a higher (0.3%) concentration of Peters Professional PL Special (15:11:29). Helleborus lividus growth in the first year of cultivation depended on the calcium carbonate dose. Taller plants, with a higher number of leaves, were produced using calcium carbonate at a dose of CaCO3 2.5-5.0 g dm-3. In the second year of cultivation good quality plants - taller, with higher numbers of leaves and shoots, were produced when grown in a substrate with 2.5-7.5 g CaCO3 per dm3. The application of solutions of various concentrations in top dressing did not have an effect on the growth of Helleborus lividus in the first year of cultivation, while in the second year taller plants, with more leaves as well as flowers and buds, were produced when applying a 0.3% fertilizer solution.