Effects of anthocyanin-rich extract from red cabbage leaves on meristematic cells of Allium cepa L. roots treated with heavy metals

The incubation of Allium cepa L. roots in Pb(NO3)2, Cd(NO3)2×4H2OCd(NO3)2×4H2O or Cr(NO3)3×9H2OCr(NO3)3×9H2O solution at the concentration of 100μM lowered the mitotic index (MI) value in meristem by 58%, 39%, 48%, respectively. The proportion of mitotic phases (mainly prophases and telophases) in MI value was also changed. Moreover, mitotic disturbances such as: c-metaphases, sticky and lagging chromosomes, chromosome bridges, binucleate cells, micronuclei, “budding” nuclei and nucleoli partly outside nuclei were induced in the presence of the tested heavy metals, most frequently after Pb treatment. Pre-incubation in the ATH-rich extract from red cabbage leaves caused 2.5%, 1.8% or 1.6% increase in MI value as compared to the meristematic cells of A. cepa   L. roots treated only with Cd, Pb, or Cr, respectively. Additionally, the ATH-rich extract was responsible for changing phase index values towards the control level in the material incubated in Pb or Cd. Moreover, the total number of mitotic abnormalities induced by the tested metals was reduced due to the preincubation in the ATH-rich extract, most effectively in the roots treated with Cd (by 23) while by half in Cr presence. These data suggest a protective action of the ATH-rich extract from red cabbage leaves against heavy metal toxicity.