RESUMO
(1)H NMR spectroscopy was used as a method for quantitative analysis of sesquiterpene lactones present in a crude lactone fraction isolated from Arnica montana. Eight main components - tigloyl-, methacryloyl-, isobutyryl- and 2-methylbutyryl-esters of helenalin (H) and 11α,13-dihydrohelenalin (DH) were identified in the studied sample. The method allows the determination of the total amount of sesquiterpene lactones and the quantity of both type helenalin and 11α,13-dihydrohelenalin esters separately. Furthermore, 6-O-tigloylhelenalin (HT, 1), 6-O-methacryloylhelenalin (HM, 2), 6-O-tigloyl-11α,13-dihydrohelenalin (DHT, 5), and 6-O-methacryloyl-11α,13-dihydrohelenalin (DHM, 6) were quantified as individual components.
Assuntos
Arnica/metabolismo , Lactonas/análise , Espectroscopia de Ressonância Magnética/métodos , Extratos Vegetais/metabolismo , Sesquiterpenos/química , Técnicas de Química Analítica , Química Farmacêutica/métodos , Desenho de Fármacos , Flores/química , Lactonas/química , Modelos Químicos , Sesquiterpenos/análise , Sesquiterpenos de GuaianoRESUMO
Rhodiola rosea L. (Crassulaceae), or "rose root" is a perennial herbaceous plant, distributed in the Northern Hemisphere. Pharmacological studies have shown that R. rosea exhibits different biological activities - antioxidant, antidepressant, anticancer, etc. The aim of this study was to compare the chemical composition of essential oils from rhizomes of three commercial samples of R. rosea originated from Bulgaria (sample 1), China (sample 2) and India (sample 3). The oils were analyzed by GC and GC-MS. Thus, the main volatile component in the Bulgaria and Chinese R. rosea was geraniol, followed by myrthenol in sample 1 or octanol in sample 2. Phenethylalcohol was a principal constituent in the Indian oil. Myrtenol and octanol were in significant amounts too. Aliphatic hydrocarbons were characteristic of the latter sample. It is notable that cinnamyl alcohol, which was present in large concentration in Bulgarian sample, was not detected in the other two samples. The obtained results showed considerable differences in the composition of the studied three origins of R. rosea.
RESUMO
This work deals with ultrasonically assisted extraction (UAE) of biologically active compounds from rhizomes of Rhodiola rosea, a popular medicinal plant. The influence of temperature, type of solvent and solid/solvent ratio on the yield of total extracts, total phenols and flavonoids was established. The best extraction of total phenols and flavonoids was achieved by using 50% aqueous EtOH and MeOH, respectively. Five times increase of solid/solvent ratio (from 1:20 to 1:100 (w/v)) leads to slow increase of the yield of total phenols and flavonoids. The extraction effectiveness of conventional maceration with 50% EtOH and UAE performed for 1 h at 25 degrees C using the same solvent with respect of total phenols was comparable.
Assuntos
Flavonoides/química , Fenóis/química , Rhodiola/química , Calibragem , Etanol , Flavonoides/isolamento & purificação , Metanol , Fenóis/isolamento & purificação , Extratos Vegetais/química , Solventes , Espectrofotometria Ultravioleta , UltrassomRESUMO
Seven new irregular linear sesquiterpene lactones, epi-antheindurolide A (1), epi-antheindurolide A-5,6-oxide (2), 5-hydroxy-5,6-dihydro-6,13-dehydro-epi-antheinduro lide A (3), 5-hydroperoxy-5,6-dihydro-6,13-dehydro-epi-antheindurolide A (4), epi-antheindurolide B (5), 6-hydroxy-5,6-dihydro-4,5-dehydro-epi-antheindurolide A (6) and 6-hydroperoxy-5,6-dihydro-4,5-dehydro-epi-antheindurolide A (7), were isolated from the flowers of Anthemis auriculata Bioss. Their structures were established by spectroscopic techniques. The discussed compounds were found to be stereoisomers of recently reported lactones for A. arvensis.
Assuntos
Anthemis/química , Lactonas/química , Sesquiterpenos/química , Flores/química , Estrutura Molecular , Ressonância Magnética Nuclear Biomolecular , EstereoisomerismoRESUMO
Sesquiterpene lactones isolated from the genus Anthemis are used as chemotaxonomic markers. The obtained results support with some exceptions the botanical classification in Flora Europaea. Discrepancy between the lactone profile, cluster analysis and classification of A. melampodina, A. macedonica and A. austriaca in the genus Anthemis is discussed. The lactone composition of the undescribed as an European species A. plutonia correlates well with the guaianolide containing group of sect. Hiorthia.
Assuntos
Anthemis/química , Biomarcadores/química , Lactonas , Sesquiterpenos , Anthemis/classificação , Lactonas/química , Lactonas/isolamento & purificação , Conformação Molecular , Sesquiterpenos/química , Sesquiterpenos/isolamento & purificação , Especificidade da Espécie , EstereoisomerismoRESUMO
The aerial parts of Anthemis austriaca Jacq. afforded five new sesquiterpene lactones (two of which are dimeric guaianolides) and three new guaiane type sesquiterpene acids In addition, seven known terpenoids were also found in the studied species. Their structures were elucidated by spectral methods.
Assuntos
Asteraceae/química , Terpenos/química , Bulgária , Indicadores e Reagentes , Espectroscopia de Ressonância Magnética , Modelos Moleculares , Conformação Molecular , Extratos Vegetais/química , Extratos Vegetais/isolamento & purificação , Terpenos/isolamento & purificaçãoRESUMO
Four new eudesmanolides and two new guaianolides were isolated from the aerial parts of Anthemis carpatica Willd. and their structures elucidated by spectral methods. In addition, seven known sesquiterpene lactones were identified.