patuletin and eriodictyol

Plants and their secondary metabolites, including flavonoids, exhibit a wide range of biological effects. Consequently, natural substances are receiving an increased attention in medicinal research. Owing to these facts, in vitro antiplatelet activity of ethanol summary extract and four flavonoids from Leuzea carthamoides was determined in human platelet-rich plasma. Arachidonic acid (AA), adenosine diphosphate (ADP), collagen (COL), and thrombin were used as agonists of platelet aggregation. The summary extract showed a significant inhibition of the aggregation induced by COL and ADP. Of the tested flavonoids, eriodictyol (1) and patuletin (2) influenced COL- and AA-induced aggregation. Their IC(50) values are presented. Flavonoid glycosides eriodictyol-7-beta-glucopyranoside (3) and 6-hydroxykaempferol-7-O-(6''-O-acetyl-beta-D[small cap]-glucopyranoside) (4) were found to be weak antiplatelet agents. These results confirmed the fact that glucosylation decreases the antiplatelet activity. Quantitative composition of tested flavonoids in L. carthamoides extract was also determined. Though two of the tested flavonoids inhibited platelet aggregation, further evaluation of L. carthamoides, in order to discover other antiplatelet active compounds and possible adverse health effects, is needed.

Topics: Adenosine Diphosphate; Arachidonic Acid; Blood Platelets; Chromones; Collagen; Dose-Response Relationship, Drug; Flavanones; Flavonoids; Humans; In Vitro Techniques; Kaempferols; Leuzea; Male; Plant Leaves; Platelet Aggregation; Platelet Aggregation Inhibitors; Platelet Function Tests; Thrombin

A simple and sensitive high-performance liquid chromatography method for the determination of four Leuzea carthamoides flavonoids, namely eriodictyol, patuletin, eriodictyol-7-beta-glucopyranoside, and 6-hydroxykaempferol-7-O-(6"-O-acetyl-beta-D-glucopyranoside), is presented. Using this method, quantitative composition of flavonoids ranged from 0.011% to 0.574% in dried plant material was determined. This method could be used in the future for the quantitative evaluation of major phenolic compounds in L. carthamoides.

Topics: Chromatography, High Pressure Liquid; Chromones; Flavanones; Flavonoids; Leuzea