Determination of the stoichiometry of the copper complexes with dehydrosilybine A

Charles University Faculty of Pharmacy in Hradec Králové Department of Pharmacology and Toxicology Candidate: Kateřina Klimková Supervisor: Assoc. Prof. Přemysl Mladěnka, Pharm. D., Ph.D. Consultant: Assoc. Prof. Kateřina Valentová, Ph.D. Title of Thesis: Determination of the stoichiometry of the copper complexes with dehydrosilybin A Silymarin, the standardized extract of the milk thistle (Silybum marianum), is a widely used approved over-the-counter drug that is recommended for a number of liver diseases. Silymarin contains as one of its components 2,3-dehydrosilybinA, which has an appropriate metal binding site in its structure. In general, flavonolignans, due to their structure, can interact with transition metals in the gastrointestinal tract by forming complexes. This property can be useful for the protection against excessive amounts of metals in the body. The aim of this in vitro study was to analyse the interaction of 2,3-dehydrosilybin A with copper, which plays a crucial role in the organism as a cofactor of many enzymes. Although being an essential element, it can, however, be toxic at elevated levels. Stoichiometry, as one of the most important characteristics of the complex, was determined by UV-Vis spectrophotometry in four (patho)physiological pH conditions (4.5; 5.5; 6.8; 7.5)...