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Aim: To reinvestigate the chemical constituents of the ethanolic extract of Meconopsis quintuplinervia Regel which is a traditional Tibetan medicine used for treatments of hepatitis, tuberculosis etc..; Methods: The compounds were enriched by column chromatography techniques over silica gel, macro porous resin and Sephadex LH-20 absorbents, and finally purified by reverse phase preparative HPLC methods with isocratic mobile phase systems of methanol-H2O-acetic acid (500:500:1) and acetonitrile-H2O-acetic acid (200:800:1). Structural determination of the pure compounds were based on extensive analyses of modern spectroscopic methods including IR, MS, HRMS, 1D- and 2D-NMR spectra.; Results: Three alkaloids were obtained and their structures were elucidated as norsanguinarine (I), O-methylflavinantine (II) and 6-methoxy-17-methyl-2, 3-[methylenebis (oxy)]-morphin-5-en-7-one (III).; Conclusion: Norsanguinarine (I) was isolated from genus Meconopsis for the first time, and 6-methoxy-17-methyl-2,3-[methylenebis(oxy)]-morphin-5-en-7-one (III) is a new alkaloid named as meconoquintupline.;
In plants with infrequent pollinator services, the benefits of reproductive assurance could be eroded by severe ovule discounting and inbreeding depression (ID). However, it remains unclear how selfing evolves under complete pollinator failure and strong ID. We examined the mating system and ID under netting and robbing conditions in <i>Comastoma pulmonarium</i> (Turcz.) Toyok. (Gentianaceae), an alpine annual experiencing a high ratio of nectar robbery on the Qinghai-Tibet Plateau. <i>Comastoma pulmonarium</i> produced seeds via selfing at the study site. No pollinator was observed and thus the nectar was consumed exclusively by robbers. Inbreeding depression occurred in the life stages of seed mass and germination, and the cumulative ID was much higher than 0.5 under netting and robbing conditions. Overall, in comparison with netting, the magnitude of ID under robbing conditions tended to decrease. Our results suggested that selfing could assure reproduction for plants under complete pollinator failure and strong ID, supporting the “better than nothing” role of selfing and providing one of the few cases of the evolution of selfing under strong ID.
OBJECTIVE: To establish a method for determination of 10 ingredients such as gentiopicroside, sweroside, and mangiferin in India swertia, and settle the index components and their limits.METHOD: By Welch materials AQ-C18 column, determination was conducted by the gradient elution with methanol and 0.4% formic acid as mobile phase, with column temperature 30 degrees C, flow rate at 1.0 mL x min(-1), and 254 nm as the detection wavelength. RESULT: The linear relatives of 10 ingredients were good. The method showed the high precision and good reproducibility, and recovery rates were between 97% and 103%. The ingredients of market com-modities varied greatly. CONCLUSION: This method is simple, sensitive, reproducible, and applicable to the determination of the main ingredients in India Swertia. Sweroside and mango glycosides were suggested as the index components for determination in Jia Di (Swertia chirayita), and their content limits are not less than 0.1%, 0.3%, respectively.
OBJECTIVE: To evaluate the medicinal reasonableness and resource utilization of Dida from different species.METHOD: With common characteristic absorption peaks of HPLC fingerprints and SPSS cluster, the composition similarity of Dida from different species was evaluated. RESULT: The composition similarity of HPLC fingerprints of 33 Dida samples from 15 species and 1 variety originated from Swertia, Halenia, Gentianopsis, Lomatogonium was difference. The original species can be clustered into four groups by the relative area of 10 common characteristic peaks of HPLC fingerprints. The compositions of four different genera are quite different. CONCLUSION: Because of containing iridoids, xanthones, and triterpenes which have liver protection and cholagogue functions, all of species from Swertia, Halenia, Gentianopsis and Lomatogonium in Gentianaceae are classified as Dida in Tibetan medicine. According to the composition difference among different species, the HPLC fingerprints established for Dida from different source are an effective means to identify nd control the quality of Dida.
OBJECTIVE: To study the chemical constituents of a Tibetan medicine Meconopsis quintuplinervia.METHOD: Column chromatographic techniques were applied to isolate constituents. A combination of IR, MS and NMR spectroscopy was used to identify structures of constituents. RESULT: Twelve compounds were isolated from the ethanolic extract and their structures were elucidated as quercetin 3-O-beta-D-glucopyranoside (I), quercetin 3-O-beta-D-galactopyranosyl-(1-->6)-glucopyranoside (II), kaempferol 3-O-beta-D-glucopyranosyl-(1-->2)-beta-D-glucopyranoside (III), isorhamnetin 3-0-beta-D-galactopyranosyl-(1-->6)-beta-D-glucopyranoside (IV), caffeic acid (V), protocatechuic acid (VI), p-hydroxycinnamic (VII), 2-(3,4-dihydroxyphenyl )-ethyl-O-beta-D-glucopyranoside (VIII), p-hydroxybenzoyl-beta-D-glucopyranoside (IX), 4-O-beta-D-glucopyranosyl-(Z)-p-coumaric acid (X), 5, 7-dihydroxy-4H-4-chromenone (XI), daucosterol (XII). CONCLUSION: Ten compounds were isolated from this genus for the first time except for XI and XII.
OBJECTIVE: To study the chemical constituents of Tibetan Madicine Wangla.METHOD: Sepearing the chemical constituents by means of chromatography and identifying their structures on the basis of MS and NMR spectra and TLC with authentic samples. RESULT: Eight compounds were isolated as 4-[(4-hydroxyphenyl) methoxy]benzenemethanol(I), 4,4'-dihydroxydiphenyl methane(II), 4,4'-dihydroxydibenzyl ether(III), gastrodin(IV), 4-hydroxy benzenemethanol(V), 4-hydroxybenz aldehyde(VI), beta-sitosterol(VII) and beta-daucosterol(VIII). CONCLUSION: All the compounds were obtained from genus Coeloglassum for the first time. The compound I is a new natural product.
OBJECTIVE: To investigate the xanthones from Tibetan medicine Halenia elliptica and their antioxidant activity.METHODS: Column chromatography over normal phase silica gel, reversed phase silica gel, Sephadex LH-20, and recrystallization techniques were used to isolate and purify constituents from Halenia elliptica. Infrared spectrometry, mass spectrometry, and nuclear magnetic resonance spectrometry were used to identify the structure of compounds. The antioxidant activity was evaluated by measuring the content of malondialdehyde product in mice liver cell microsomal induced by ferrous-cysteine. RESULTS: Eight xanthones (compound I-VIII) were isolated and identified from the ethyl acetate extract of Halenia elliptica, among which 1,7-dihydroxy-2,3,5-trimethoxyxanthone was a novel compound. Compound I, III at 10 microg/ml and 100 microg/ml could inhibit the production of malondialdehyde in mouse liver microsomes in vitro. CONCLUSION: Eight xanthones were isolated and they have certain antioxidant activity.