Chromium is essential in organism e.g., for the correct metabolism of glucose (an ingredient of the glucose tolerance factor ñ GTF), but it is also a toxic metal. Toxicity of chromium depends closely on its valence and is connected substantially with its oxidative properties. Cr(VI) is classified by IARC as carcinogenous for people (1, 2). Scutellaria baicalensis is a Chinese plant rich in flavonoids, especially baicalin, baicalein and wogonosid (3, 4). The extract received from this plant ñ

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... oxyd (Bioactive Products Factory) showed to be an active radicals scavenger, also inhibiting the lipid peroxidation caused by chromium compounds (5). It was interesting to know whether baicalin, abundantly present in Antoxyd, can be responsible for this effect. In this study baicalinís influence on lipid peroxidation caused by chromium in human erythrocytes was evaluated. Also the scavenging ability of baicalin towards the hydroxyl radical generated by chromium ions in mitochondria of the human placenta was investigated. The aim of the study was to examine baicalinís interaction with chromium ions as well. EXPERIMENTAL The materials used in the research were fresh blood and mitochondria. The blood taken on the sodium citrate was obtained from The Casualty Department of the Surgery patients of the Academic Hospital in Wroc≥aw. It was centrifuged and the plasma was rejected. The erythrocytes were washed three times with physiological salt solution and then a 10% suspension of blood corpuscles in PBS buffer was prepared. The level of hemoglobin was measured by Drabkin method. Mitochondria were received from the human placenta (Department of Reproduction and Obstetrics, University of Medicine in Wroclaw) from physiological deliveries. Placenta after the initial purification were homogenized in the TRIS-HCl buffer pH 7.4 containing 0.23 M mannitol; 0.07 M sucrose; 1 mM EDTA and 0.2% bovine serum albumin (BSA) and were proceeded acc. to (6). The concentration of the protein was evaluated with Lowry method. The TBARS (thiobarbituric acid reactive species) level was measured using Stocksí method (7) with thiobarbituric acid (TBA) at the wave length of 535 nm. The TBARS concentration was expressed in nmol/g Hb. The ∑ OH level (hydroxyl radical) was evaluated colorimetrically by the measurement of the deoxyribose degradation, at the wavelength of 532 nm (8). The concentration of the ∑ OH radical was expressed in nmol/mg proteins. Baicalin (Baicalin, 95%; Sigma-Aldrich) was used at the following concentrations: 1; 10; 20; 100 and 200 µmol/mL in DMSO (dimethyl sulfoxide). Aqueous solution of salt chromium III (CrCl 3 ∑6H 2 O p.p.a; Riedel de Haen) and chromium VI (K 2 Cr 2 O 4 p.p.a.; POCh) at concentrations of 0.05; 0.5 and 1 µg/mL were used. The results were evaluated statistically using the one-factor analysis ANOVA and the post hoc RIR Tukeyís test (p < 0.05). RESULTS AND DISCUSSION Baicalin at concentrations from 10 µmol/mL to 200 µmol/mL showed its antioxidative effect by the decrease of TBARS level in the erythrocytes (p < 0.001) in comparison to the control K1 (Fig. 1) . It was observed that there was a statistically significant linear negative correlation between the