首页 | 本学科首页   官方微博 | 高级检索  
相似文献
 共查询到20条相似文献,搜索用时 990 毫秒
1.
A high yield of betulinic acid (up to 17% from the ethanolic extract) was found in the leaves of Eugenia florida collected in south-eastern Brazil, making this species a potential commercial source of the title compound. Extracts of E. florida were subjected to solvent partition, and rapid high-speed counter-current chromatography (HSCCC) was applied to the semi-crude extracts to afford betulinic acid in high purity. The mobile and stationary phases were derived from the two-phase solvent system composed of n-hexane-ethyl acetate-methanol-water (10:5:2.5:1). The developing solvent system (stationary and mobile phases) for optimum HSCCC separation was chosen by dissolving the fraction to be chromatographed in the proposed solvent mixture and determining the amount of betulinic acid in each phase by densitometric TLC. Purified betulinic acid was characterized by 13C-NMR, GC-MS and co-injection of its methyl ester with standards in GC-FID. The HSCCC technique is commonly employed to isolate triterpene glycosides, but is applied in this study to an aglycone.  相似文献   

2.
Black cohosh (Actaea racemosa L. syn. Cimicifuga racemosa (L.) Nutt.), a North American perennial plant, is a promising natural alternative to hormone replacement therapy for treating menopausal symptoms, but the mechanism of action is not understood. The clinical actions of this plant have been attributed to the isoflavonone formononetin since 1985, when its presence was reported in a black cohosh extract. Others have since looked for formononetin, but have not detected it. We looked for formononetin in extracts of black cohosh roots and rhizomes collected in thirteen locations in the eastern United States, including Maryland, New Jersey, New York, North Carolina, Pennsylvania, Virginia, and Tennessee. The rhizome samples were extracted using 80% methanol, and the extracts were partially purified using solid-phase extraction to concentrate any isoflavonoids that might be present. We tested for formononetin in these partially purified samples using thin-layer chromatography and high-performance liquid chromatography with a photodiode array detector and a mass spectrometer. Formononetin was not detected in any of the thirteen plant populations examined. Remifemin, a German product now on the United States market, and CimiPure, a commercially available black cohosh rhizome extract, were also analyzed. We did not detect formononetin, or ononin (formononetin-7-glucoside), in any sample tested by the above-mentioned chemical analyses. Therefore, the clinically observed estrogen-like actions of black cohosh, such as reduction of hot flashes, are likely due to a compound, or combination of compounds, other than formononetin.  相似文献   

3.
Four phenylpropanoid esters, cimiracemates A-D (1-4), along with three known compounds, isoferulic acid, ferulic acid and methyl caffeate were isolated from the EtOAc fraction of the rhizome of Cimicifuga racemosa. The structures of the esters were elucidated by means of spectral data, including 2D NMR spectroscopy.  相似文献   

4.
The roots of Anemone altaica Fisch. ex C. A. Mey. have been used in the treatment of epilepsia, neurasthenia, and arthritis in Chinese folk medicine for a long time. In order to find new and bioactive compounds, the chemical constituents of the roots of A. altaica were investigated and nine compounds were isolated from the EtOH extract of this plant. On the basis of spectroscopic methods, the structures of these compounds were elucidated as 4-(9H-β-carbolin- 1-yl)-4-oxo-butyric acid (1), carboxymethyl isoferulate (2), isoferulic acid (3), cirsiumaldehyde (4), 5-hydroxy-4-oxo-pentanoic acid (5), triacontane (6), palmic acid (7), β-sitosterol (8), and daucosterol (9). Among them, 1 and 2 were new compounds, and 3 and 4 were obtained from this genus for the first time.  相似文献   

5.
Triterpene glycosides from the roots of Sanguisorba officinalis   总被引:1,自引:0,他引:1  
Five triterpene glycosides were isolated from the MeOH extract of Sanguisorba officinalis (Rosaceae) roots, as confirmed by detailed analysis of their 1H, 13C, and two-dimensional NMR data, and by the results of hydrolytic cleavage. Three known triterpenes and six known triterpene glycosides were also isolated and identified. The isolated compounds were evaluated for their cytotoxic activities against HSC-2 cells and HGF.  相似文献   

6.
Despite their high nutritional value and a lack of physical defenses, most marine sponges appear to be minimally affected by predators, competitors, and fouling organisms, possibly due to sponge chemical defenses. In the last 15 years, several triterpene glycosides have been isolated from sponges, but their ecological or physiological roles are largely unknown. We tested triterpene glycosides from Erylus formosus and Ectyoplasia ferox, Caribbean sponges belonging to two different orders, in field and laboratory assays for effects on fish feeding, attachment by potential biofilm-forming bacteria, fouling by invertebrates and algae, and overgrowth by neighboring sponges. Formoside and other triterpene glycosides from Erylus formosus deterred predation, microbial attachment, and fouling by invertebrates and algae. Triterpene glycosides from Ectyoplasia ferox were found to be antipredatory and allelopathic. Thus, triterpene glycosides in these sponges appear to have multiple ecological functions. Tests with different triterpene glycosides at several concentrations indicated that small differences in molecular structure affect ecological activity. In order to establish whether triterpene glycosides could be involved in water-borne versus surface-mediated interactions, the presence of triterpene glycosides in the seawater surrounding live sponges was measured using two in situ sampling methods followed by HPLC and NMR spectral analysis. Water-borne triterpene glycosides were below detection limits for both species. However, top sponge layers and swabs of the surfaces of both sponges contained sufficiently high concentrations of triterpene glycosides to deter bacterial settlement and fouling of Erylus formosus surfaces and overgrowth of Ectyoplasia ferox by neighboring sponges. Enemies of these sponges appear to be deterred by surface contact of triterpene glycosides rather than by water-borne interactions. The dual strategy of employing one group of compounds for multiple purposes and minimizing the loss of compounds into seawater suggests that these organisms utilize chemical defenses with efficiency.  相似文献   

7.
Berry extracts rich in anthocyanins have been linked to protective effects including the modulation of age-related neurological dysfunction and the improvement of the resistance of red blood cells against oxidative stress in vitro . In this study the bioavailability, metabolism and elimination of polyphenols from blackcurrant juice, rich in anthocyanins, flavonols, and hydroxycinnamates, were investigated. The four major native anthocyanidin glycosides of blackcurrant juice, delphinidin-3-glucoside, delphinidin-3-rutinoside, cyanidin-3-glucoside and cyanidin-3-rutinoside, were detected and identified in low amounts by HPLC and LC-MS in plasma and urine post-ingestion. Elimination of the anthocyanins was fast (maximum excretion after 1 h) and plasma levels (0-128.6 nmol/l) and total urinary excretion (0.07-1.35 mg; 0.007-0.133% of the dose ingested) were low. Most significantly, of the hydroxycinnamates, conjugated and free ferulic, isoferulic, p -coumaric, sinapic and vanillic acids were identified in plasma and urine, using GC-MS techniques. Quercetin and kaempferol (as glucuronides) and the proposed colonic metabolite of quercetin, 3-hydroxyphenylacetic acid, were detectable in a minority of subjects. Increased daily urinary hippuric, 4-hydroxyhippuric and 3-hydroxyhippuric acid levels were also observed post-ingestion in all volunteers.  相似文献   

8.
《Free radical research》2013,47(11):1229-1241
Berry extracts rich in anthocyanins have been linked to protective effects including the modulation of age-related neurological dysfunction and the improvement of the resistance of red blood cells against oxidative stress in vitro . In this study the bioavailability, metabolism and elimination of polyphenols from blackcurrant juice, rich in anthocyanins, flavonols, and hydroxycinnamates, were investigated. The four major native anthocyanidin glycosides of blackcurrant juice, delphinidin-3-glucoside, delphinidin-3-rutinoside, cyanidin-3-glucoside and cyanidin-3-rutinoside, were detected and identified in low amounts by HPLC and LC-MS in plasma and urine post-ingestion. Elimination of the anthocyanins was fast (maximum excretion after 1 h) and plasma levels (0-128.6 nmol/l) and total urinary excretion (0.07-1.35 mg; 0.007-0.133% of the dose ingested) were low. Most significantly, of the hydroxycinnamates, conjugated and free ferulic, isoferulic, p -coumaric, sinapic and vanillic acids were identified in plasma and urine, using GC-MS techniques. Quercetin and kaempferol (as glucuronides) and the proposed colonic metabolite of quercetin, 3-hydroxyphenylacetic acid, were detectable in a minority of subjects. Increased daily urinary hippuric, 4-hydroxyhippuric and 3-hydroxyhippuric acid levels were also observed post-ingestion in all volunteers.  相似文献   

9.
Triterpene glycosides from Schefflera octophylla.   总被引:1,自引:0,他引:1  
T V Sung  W Steglich  G Adam 《Phytochemistry》1991,30(7):2349-2356
In addition to 3-epi-betulinic acid, three triterpene glycosides were isolated from leaves of Schefflera octophylla. The structures of the glycosides have been determined as 28-O-[alpha-L-rhamnopyranosyl(1----4)-O-beta-D-glucopyranosyl(1----6)-be ta-D- glucopyranosides of 3 alpha-hydroxy-lup-20(29)-ene-23,28-dioic acid, 3 alpha,11 alpha- dihydroxy-lup20(29)-ene-23,28-dioic acid and 3-epi-betulinic acid by spectroscopic data and chemical transformations. The last two compounds were found for the first time in the plant kingdom.  相似文献   

10.
11.
Aqueous leachates of roots of the perennial weed Pluchea lanceolata (DC.) C. B. Clarke, its root-incorporated soil and rhizosphere soil, interfered with the seedling growth of certain plant species. The soils from the rhizosphere zone of this plant had significantly higher total phenolics and HPLC analysis revealed that phenolic fractions represented by retention times of 1.6, 1.9, 2.5 (simple phenol, chlorogenic acid and phloroglucinol respectively), 3.7 and 4.3 min were contributed by roots of the weed to the soil. The phenolic fraction represented by the retention time 3.3 (formononetin 7-O-glucoside) was detected in the weed's rhizosphere soils and not in the rootincorporated soils. UV spectral studies established the presence of phloroglucinol, simple phenol, chlorogenic acid, formononetin 7-O-glucoside, and methylated coumarins in the root leachate, which affect the seedling growth of mustard ( Brassica juncea ). Present research established the allelopathic potential of P. lanceolata roots, and the possible involvement of allelopathy in its interference success.  相似文献   

12.
Liu BS  Yi YH  Li L  Sun P  Han H  Sun GQ  Wang XH  Wang ZL 《化学与生物多样性》2008,5(7):1425-1433
Two new triterpene glycosides, argusides D and E (1 and 2, resp.), have been isolated from the sea cucumber Bohadschia argus Jaeger collected in the South China Sea. Their structures have been established by spectral analysis (ESI-MS, and 1D- and 2D-NMR) and chemical evidence. Compounds 1 and 2 both possess an holostane-type triterpene aglycone with a C(9)=C(11) bond, an OH group at C(12), and tetrasaccharide moieties, but differ in the side chains. The two glycosides exhibited significant cytotoxicities against four human tumor cell lines, A549, HCT-116, HepG2, and MCF-7.  相似文献   

13.
The chemical components of the volatiles from Vetiveria zizanioides were analyzed by SPME and GC-MS. In the roots, the main component was valencene (30.36%) abstract, while in the shoots and leaves, they were 9-octadecenamide (33.50%) abstract, 2,6,10,15,19,23-hexamethyl-2,6,10,14,18,22-tetracosahexaene (27.46%) abstract, and 1,2-benzendicarboxylic acid, diisooctyl ester(18.29%) abstract The results showed that there were many terpenoids in the volatils. In shoot volatiles, there existed 3 monoterpenes, 2 sesquiterpenes and 1 triterpene. Most of the volatiles in roots were sesquiterpenes.  相似文献   

14.
香根草挥发物化学成分的分析   总被引:8,自引:2,他引:6  
The chemical components of the volatiles from Vetiveria zizanioides were analyzed by SPME and GC-MS. In the roots, the main component was valencene (30.36%), while in the shoots and leaves, they were 9-octadece-namide (33.50 % ), 2, 6, 10, 15, 19, 23-hexamethyl-2, 6, 10, 14, 18, 22-tetracosahexaene (27.46% ), and 1,2-benzendicarboxylic acid, diisooctyl ester(18.29% ). The results showed that there were many terpenoids in the volatils. In shoot volatiles, there existed 3 monoterpenes, 2 sesquiterpenes and 1 triterpene. Most of the volatiles in roots were sesquiterpenes.  相似文献   

15.
Liu BS  Yi YH  Li L  Sun P  Yuan WH  Sun GQ  Han H  Xue M 《化学与生物多样性》2008,5(7):1288-1297
Two new triterpene glycosides, argusides B and C (1 and 2, resp.), have been isolated from the sea cucumber Bohadschia argus Jaeger collected in the South China Sea. Their structures have been established by spectral analysis (2D-NMR and ESI-MS) and chemical evidence. Compounds 1 and 2 both possess a holostane-type triterpene aglycone with a C(9)==C(11) bond and a OH group at C(12), but differ in their substituents at C(17) and the hexasaccharide moiety. The two glycosides exhibited significant cytotoxicities against four human tumor cell lines (A549, HCT-116, HepG2, and MCF-7). In comparison with the positive control V-16 (etoposide), 1 and 2 showed higher cytotoxicities to A549 and HCT-116 cell lines.  相似文献   

16.
Baibutoside (5), a new cycloartane-type triterpene glycoside, has been isolated from the roots of Astragalus baibutensis along with four known glycosides, acetylastragaloside I (1), and astragalosides I, II, and IV (2-4, resp.). The structure elucidation of the compounds were achieved by a combination of one- and two-dimensional NMR techniques (DQF-COSY, HSQC, HMBC, and ROESY), and mass spectrometry (ESI-MS), where all the compounds were shown to have cycloastragenol (=(20R,24S)-3beta,6alpha,16beta,25-tetrahydroxy-20,24-epoxy-9,19-cyclolanostane) as aglycone. All compounds were tested for in vitro antiprotozoal activity. Compounds 1-4 displayed notable activity vs. Trypanosoma brucei rhodesiense, with acetylastragaloside I (1) being the most potent (IC50 9.5 microg/ml). Acetylastragaloside I (1) was also lethal to T. cruzi (IC50 5.0 microg/ml), and it is the first cycloartane-type triterpene with remarkable trypanocidal activity against both T. brucei rhodesiense and T. cruzi. However, it exhibits some cytotoxicity on mammalian cells.  相似文献   

17.
Balanophora involucrata Hook .f. & Thomson (Balanophoraceae) is a parasite plant often growing on the roots of leguminous plants. The whole herb has been used medicinally for the treatment of irregular menstruation, cough, hemoptysis, traumatic injury and bleeding, dizziness and gastralgia in Yunnan Province, China. The 2,2‐diphenyl‐2‐picrylhydrazyl (DPPH) assay on the 60% aq. acetone extract of the fresh whole plant of B. involucrata showed considerable radical‐scavenging activity (SC50 15.3 μg/ml). Further purification on the extract led to the isolation of one new phenolic glycoside, sieboldin‐3′‐ketocarboxylic acid ( 1 ), and one new cyanogenic glycoside, proacacipetalin 6′‐Oβ‐D ‐glucopyranoside ( 2 ), together with 26 known compounds including three 4″‐O‐galloyl and 2″,3″‐O‐(S)‐hexahydroxydiphenoyl (HHDP) derivatives of dihydrochalcone glucosides, seven hydrolyzable tannins, and alkane glycosides. The cyanogenic compound isolated from the Balanophoraceae family for the first time might be a signal molecule between B. involucrata and its hosts. The free‐radical‐scavenging activity of the isolated compounds was also examined by DPPH assay.  相似文献   

18.
The medicinal plants of Huang-qi (Radix Astragali) and Sheng-ma (Cimicifuga foetida) demonstrate significantly better antioxidant effects when used in combination than when used alone. However, the bioactive components and interactional mechanism underlying this synergistic action are still not well understood. In the present study, 2,2-diphenyl-1-picrylhydrazyl (DPPH) radical scavenging assay was employed to investigate the antioxidant capacity of single herbs and their combination with the purpose of screening synergistic antioxidant compounds from them. Chromatographic isolation was performed on silica gel, Sephadex LH-20 columns and HPLC, and consequently to yield formononetin, calycosin, ferulic acid and isoferulic acid, which were identified by their retention time, UV λmax, MS and MS/MS data. The combination of isoferulic acid and calycosin at a dose ratio of 1∶1 resulted in significant synergy in scavenging DPPH radicals and ferric reducing antioxidant power (FRAP) assay. Furthermore, the protective effects of these four potential synergistic compounds were examined using H2O2-induced HepG2 Cells bioassay. Results revealed that the similar synergy was observed in the combination of isoferulic acid and calycosin. These findings might provide some theoretical basis for the purported synergistic efficiency of Huang-qi and Sheng-ma as functional foods, dietary supplements and medicinal drugs.  相似文献   

19.
Homology based PCRs with degenerate primers designed from the conserved sequences among the known oxidosqualene cylases (OSCs) have resulted in cloning of a triterpene synthase (KcMS) from the young roots of Kandelia candel (L.) Druce (Rhizophoraceae). KcMS consists of a 2286 bp open reading frame, which codes for 761 amino acids. The deduced amino acid sequence showed 79% homology to a lupeol synthase from Ricinus communis suggesting it to be a lupeol synthase of K. candel. KcMS was expressed in a lanosterol synthase deficient yeast with the expression vector pYES2 under the control of GAL1 promoter. GC-MS analysis showed that the transformant accumulated a mixture of lupeol, beta-amyrin and alpha-amyrin in a 2:1:1 ratio, indicating that KcMS encodes a multifunctional triterpene synthase, although it showed high sequence homology to a R. communis lupeol synthase. This is the first OSC cloning from mangrove tree species.  相似文献   

20.
Eupatorium cannabinum subsp. corsicum (L.) is an endemic subspecies from the island of Corsica. The essential oil from the roots of this aromatic plant has been studied by GC, GC-MS and by 13C-NMR. In contrast to the essential oil from the aerial parts, which is dominated by hydrocarbon compounds (76.9%) and particularly by sesquiterpene components (43.3%), the essential oil from the roots was characterized by a high content of oxygenated compounds (61.0%), particularly oxygenated monoterpenes (54.0%). In the root oil, 106 components were identified representing 96.1% of the total amount. This oil was dominated by the monoterpenes esters (33%), the major components of which were neryl isobutyrate (17.6%), thymyl methyl oxide (15.1%), delta-2-carene (14.5%) and beta-pinene (5.7%). Aromatic esters, nerol derivatives (esters and diesters) and a benzofuran were investigated by GC-MS using different ionization modes including electron impact ionization, and positive- and negative-chemical ionization. These components have not previously been reported in the essential oil of aerial parts of E. cannabinum from Corsica island.  相似文献   

设为首页 | 免责声明 | 关于勤云 | 加入收藏

Copyright©北京勤云科技发展有限公司  京ICP备09084417号