Multi-instrumental Investigation of the Effect of Cadmium(II) and Lead(II) Ions on Early Somatic Spruce Embryos

The main aim of this work was to use multi-instrumental analytical apparatus to investigate the effects of treatment with cadmium(II) and/or lead(II) ions (50, 250 and 500 μM) for twelve days on early somatic spruce embryos (ESEs). Primarily we used image analysis for estimation of growth and a fluorimetric sensor for enzymatic detection of viability of the treated ESEs. It follows from the obtained results that Cd caused higher toxicity to ESEs than Pb. Besides this fundamental finding, we observed that ESEs grew and developed better in the presence of 500 μM of the metal ions than in the presence of 250 μM. Based on the results obtained using nuclear magnetic resonance this phenomenon was related to an increase of the area of ESE clusters by intensive uptake of water from the cultivation medium, due to dilution of the heavy metal concentration inside the cluster. In addition we studied the glutathione content in treated ESEs by the adsorptive transfer stripping technique coupled with the differential pulse voltammetry Brdicka reaction. GSH contents increased up to 148 ng/mg (clone 2/32) and 158 ng/mg (clone PE 14) after twelve day long treatment with Cd-EDTA ions. The GSH content was about 150 and 160 % higher in comparison with the ESEs treated with Pb-EDTA ions, respectively. The difference between GSH contents determined in ESEs treated with Pb-EDTA and Cd-EDTA ions correlates with the higher toxicity of cadmium(II) ions.