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The content of the main flavonoids in the root of Scutellaria baicalensis Georgi cultivated in Central Europe was evaluated using the new simple RP-HPLC method with gradient of acetonitrile in mobile phase. The main components of the roots were baicalin (8.12% of dry root mass) and wogonin glucuronide (2.52%). The content of flavonoids was comparable with the content in plants cultivated in natural localities. Five main flavonoids were evaluated for their scavenging ability with DPPH radical-generating system and due to limited solubility only two flavonoids were investigated for their ability to scavenge hydroxyl radical by the aromatic hydroxylation method. The total extract was also tested in both the experimental arrangements. In experiments with DPPH, only baicalin and baicalein displayed a significant scavenging effect, while the production of OH radicals generated by UV photolysis of H(2)O(2) was considerable decreased in the presence of baicalin and wogonin glucuronide. After comparison with results obtained for the total extract, it was concluded, that the scavenging activity of the extract against DPPH is mainly derived from baicalin. On the other hand, baicalin, wogonin glucuronide and probably other flavonoids participate in scavenging OH radical.

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Quaternary benzo(c)phenanthridine alkaloids are a relatively small group of isoquinoline alkaloids with attractive biological activities. They are produced by a number of plant species of the Papaveraceae, Fumariaceae, and Rutaceae families. Differential cytotoxicity of minor, naturally occurring derivatives sanguirubine, chelirubine, and macarpine and better known benzophenanthridines sanguinarine and chelerythrine in cancer and normal cells was assessed in vitro by MTT assay using a panel consisting of either transformed cell lines (HeLa; A431; HL60) or primary fibroblasts of human origin. IC 50 values were determined 72 h after addition of the alkaloids. A wide range (0.01-1.44 mg=mL) of IC 50 was observed, and the highest toxicity was determined for macarpine. Human promyelocytic leukemia line HL60 has been documented to be the most sensitive to alkaloid treatment followed by human skin fibroblasts, while human cervix adenocarcinoma HeLa cells and epidermal carcinoma cells A431 appeared more resistant. The most sensitive cell line HL60 was selected for demonstrating the ability of the alkaloids to induce apoptosis by analyzing morphologic changes upon DAPI staining, ultrastructural changes, and annexin V versus propidium iodide staining assay. Apoptosis was induced by sanguirubine, chelirubine, chelerythrine, and macarpine at a concentration of 1 mg=mL. The results show that the alkaloids tested have a strong antiproliferative effect in vitro due predominately to apoptosis.

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The structure of chelerythrine free base was examined. When chelerythrine chloride [lb] was treated with aqueous K2CO} solution, bis[6-(5,6-dihydrochelerythrinyl)] ether[3] was obtained. An excess of aqueous ammonia under the same conditions yielded bis [6-(5,6-dihydrochelerythrinyl)] amine [4], The structures of both derivatives were determined by elemental analysis, ir, ID and 2D nmr, eims, and cims. The formation of an unstable hydroxy adduct 2a (pseudobase) was observed in 'H-nmr experiments only.