Saša Ratković

Learn More
Two different fractions of manganese were found in the maize plant root apoplasm (intercellular space containing cell walls) after soaking the roots in MnCl2 solutions (concentration range 0.01-10 mmol.l-1): (a) an Mn2+ fraction in the water free space (WFS) which gave a characteristic six-line spectrum, and (b) an immobilized fraction that gave no(More)
The proton NMR relaxation of water in maize roots in the presence of paramagnetic centers, Mn2+, Mn- EDTA2 -, and dextran-magnetite was measured. It was shown that the NMR method of Conlon and Outhred (1972, Biochem. Biophys. Acta. 288:354-361) can be applied to a heterogenous multicellular system, and the water exchange time between cortical cells and the(More)
The hydration mechanism of various plant seeds has been investigated by a) sorption-desorption isotherms, b) ac-dielectric spectroscopy in the 10 Hz to 1 GHz frequency range and the -80 to + 40 degrees C temperature range, and c) thermally stimulated depolarization current techniques in the -170 to + 23 degrees C temperature range. Seeds of different(More)
Two different pulse sequences used in 1H NMR spectroscopy termed free induction decay amplitude recovery (FIDAR) and spin-echo recovery (SER) were applied to studies of transport of paramagnetic ions in multicellular systems. The molar relaxivity of several paramagnetic species (Fe3+, Co2+, Ni2+, Cu2+, Mn2+, MnEDTA2-, dextran-magnetite) in water solutions(More)
We review here the recent achievements in high resolution NMR spectroscopy of four biologically most important nuclei (1H, 13C, 15N, 31P) applied on plant seeds in vivo or on extracts from the same tissue. Most often used nuclei in NMR analysis of seeds were protons (1H). The application of low resolution NMR for nondestructive analysis of moisture and oil(More)
The effect was studied of biochemical and morphological changes induced by antithyroid substances (PTU, C10(-4)) on proton spin-relaxation properties of rat thyroid gland. It was found that thyroid stimulated by PTU (0.05%) or C10(-4) (1.0%) exhibit marked morphological changes (hyperplasia and epithelial hypertrophy) with alteration of the soluble(More)
The osmotic changes in root cells of Zea mays L. under the effect of mannitol (concentration range 1-15%; range of osmotic pressures: -0.13 to -2.01 MPa) were studied by measuring time and concentration dependence of water self-diffusion constant (Deff) and proton spin-lattice relaxation time (T1) using proton NMR relaxation spectroscopy. In addition, in(More)
  • 1