Influence of extract from shoots of Taxus baccata var. 'Elegantissima' on mitotic activity of meristematic cells of Allium cepa L. roots

Abstract

We investigated the influence of different concentrations of alcoholic extract from young shoots of <em>Taxus baccata</em> var. 'Elegantissima' (TbE), containing paclitaxel (81.6 µg/g fresh mass), on mitotic activity and DNA content in meristematic ` cells of <em>Allium cepn</em> adventitious root tips. During 24 hours of incubation we obtained different level of inhibition of mitotic activity: ranging from slight changes (dilution 1:32), through complete inhibition reversible in postincubation (dilution 1:8), to whole inhibition irreversible in postincubation (dilution 1:4). Inhibition of mitotic activity was connected with an increase of prophases and metaphases and changes in morphology of chromosomes (thick chromosomes of prophases with diluted karyolymph and c-metaphases). During the experiment, the number of aberrations and micronuclei didn't increase but the number of cells with replicated DNA (4C) blocked in G2 phase was higher. This study was done by a flow cytometry method. The optimal concentration of the TbE extract, which inhibited mitotic activity, did not damage the genetic material (chromosomes) visibly

Polygala extraaxillaris: oxidative stress in Brachiaria decumbens mediated by volatile oils

“…The growth interference of B. decumbens in the presence of volatile oils is associated with interferences in the process of cell division, by means of partial blocking of subsequent phases of division at higher concentrations, which may be associated with changes in the structure of chromosomes in prophase and metaphase, as well as disturbances in prophase and anaphase. Similar changes were observed in A. cepa cell chromatids submitted to a Taxus baccata aqueous extract (Majewska et al, 2000).…”

Atividade fitotóxica de Croton doctoris S. Moore

“…Esse fato pode ser atribuído à capacidade dos compostos presentes na FAE em reduzir o índice mitótico, bloqueando parcialmente as fases subsequentes da divisão celular nas maiores concentrações. Mudanças semelhantes Ciência Rural, v.43, n.4, abr, 2013. foram observadas nas cromátides das células de A. cepa, submetidas ao extrato aquoso de Taxus baccata (MAJEWSKA et al, 2000). Essa interferência na divisão celular causada pela ação das substâncias químicas contidas na FAEC com acentuado efeito sobre a morfologia do sistema radicular provavelmente representa um dos mecanismos de ação das substâncias (s) com atividade fi totóxica.…”

Flow cytometry – a modern method for exploring genome size and nuclear DNA synthesis in horticultural and medicinal plant species

“…Using this strategy, Sánchez-Moreiras et al (2008) found that benzoxazolin-2(3H)-one, an allelopathic compound produced by Secale cereale, retarded the cell cycle in L. sativa root meristems by blocking the G 2 /M checkpoint. Similar effects on A. cepa root tips were induced by extracts of the medicinal plants Rhodiola rosea, Taxus baccata, and T. brevifolia (Majewska et al, 2000(Majewska et al, , 2003(Majewska et al, , 2008. Roots of A. cepa were also used to determine the mode of action of cyanamide, an allelochemical produced by Vicia villosa (Soltys et al, 2011).…”