QUANTITATIVE ESTIMATION OF FLAVONOIDS IN THE VEGETATIVE AND REPRODUCTIVE ORGANS OF SHOWY TICK TREFOIL (DESMODIUM CANADENSE) G. Puodziunene, 1 V. Janulis, 1 L. Ivanauskas, 1 A. Lukosius, 1 Z. Barsteigene, 1 and V. Ribokaite 2 Translated from Khimiko-Farmatsevticheskii Zhurnal, Vol. 43, No. 6, pp. 18 – 21, June, 2009. Original article submitted July 28, 2008. Qualitative and quantitative analysis of flavonoids in the vegetative and reproductive organs of showy tick trefoil [Desmodium canadense (L) DC., Fabaceae] herbs (stems, leaves, buds, inflorescences, legumes, and seeds) collected at various stages of vegetation at the Department of Medicinal Herbs of the Kaunas Botanical Garden (Vytautas Magnus University) was performed using HPLC techniques. A total of 15 flavonoids of aglycon and glycoside nature including apigenin, apigenin-7-O-glycoside, luteolin, rutin, vicenin-2, vitexin, isovitexin, vitexin rhamnoside, orientin, homoorientin, quercitrin, quercetin, hyperoside, astragalin, and kaempferol were identified. Among the vegetative organs, the maximum amount of flvaonoids was found in leaves, where the total content of flavonoids was 23,952.2 mg/g in the budding phase and reached a maximum of 25,472.71 mg/g (2.55%) at the ripening phase (1.88 times greater than in herbs at the beginning of flower- ing). In stems, the maximum amount of flavonoids (2,318.0 mg/g) was accumulated in the budding phase while the minimum (1,910.77 mg/g) was found at the beginning of seed ripening phase. the maximum amount of flavonoids in the reproductive organs was found in inflorescences, where the total content of flavonoids was 8,164.1 mg/g at the budding phase, reached a maximum of 15,226.39 mg/g in the full flowering phase, and then gradually decreased. Legumes at the beginning of ripening contained 8,892.3 mg/g flavonoids while seeds in the fully ripened phase contained only 4,270.1 mg/g (0.43%) flavonoids. Among the individual flavonoids, orientin and homoorientin predominated in all cases. Thus, not only the inflorescences of showy tick trefoil but also leaves can be used as medicinal raw material. The optimum time for collecting leaves for the raw material is from the budding phase until the beginning of fruit ripening. Key words: showy tick trefoil (Desmodium canadense), herbs, flavonoids, vegetative organs, reproductive organs, vegetative phase. Our previous investigation of the qualitative and quanti- tative flavonoid content in Desmodium canadense herb col- lected in various vegetative phases in the Department of Me- dicinal Herbs of the Kaunas Botanical Garden (Vytautas Magnus University) used HPLC to identify 15 algycon and glycoside flavonoids: apigenin, apigenin-7-O-glycoside, lu- teolin, rutin, vicenin-2, vitexin, isovitexin, vitexin rhamnoside, orientin, homoorientin, quercitrin, quercetin, hyperoside, astragalin, and kaempferol [1]. Collection of the medicinal raw material, D. canadense herb, was recom- mended at the beginning of flowering when the greatest quantity of flavonoids had accumulated (up to 1.36%). Therefore, it seemed interesting to establish the distribution of flavonoids in the vegetative and reproductive organs of D. canadense in various vegetative phases. EXPERIMENTAL Tops of D. canadense stems about 40 cm in length in various vegetative phases such as budding, the beginning of flowering, full flowering, the beginning of fruiting, and fully ripe fruit were collected. The collected material was divided into stems, leaves, buds, inflorescences, legumes, and seeds. Standard samples, reagents, extraction, chromatographic analysis, and statistical processing of results have been previ- ously reported [1]. 324 0091-150X/09/4306-0324 © 2009 Springer Science+Business Media, Inc. Pharmaceutical Chemistry Journal Vol. 43, No. 6, 2009 1 Kaunas University of Medicine, Kaunas, Lithuania. 2 Herbaria Drugstore, Kaunas, Lithuania.