1. Institute of Chemistry, Faculty of Science, P. J. Šafárik University; Košice Slovakia
2. Central Laboratories, Faculty of Chemical and Food Technology; Slovak University of Technology in Bratislava; Bratislava Slovakia
3. Centre of the Region Haná for Biotechnological and Agricultural Research, Department of the Phytochemistry, Faculty of Science; Palacký University; Olomouc Czech Republic
4. Institute of Physics, Czech Academy of Sciences; Praha Czech Republic