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1.
During a survey of 6 Eurasian and 10 South American Briza species for leaf flavonoids, 27 components were found. Twelve of these were identified: tricin 5-glucoside, tricin 7-glucoside, quercetin 3-glucoside, kaempferol 3-glucoside, vitexin, isovitexin, orientin, iso-orientin, and the 4′-O-glucoside of all 4 glycoflavones, 3 of which are reported for the first time. The Eurasian species, with the exception of Briza maxima, are remarkably uniform in their flavonoid pattern, accumulating mainly vitexin and isovitexin; whereas the South American species are characterized by the presence of orientin, iso-orientin and 9 unidentified flavonoids. In Briza media and the South American species, ploidy level is shown to play a large part in flavonoid variation. Examination of 12 diploid and 8 autotetraploid plants of B. media revealed that diploids accumulate vitexin and isovitexin, whereas tetraploids accumulate orientin and iso-orientin, autotetraploidy having apparently upset regulatory genes in the formation of the flavone C-glycosides. Mild alkaline treatment of both isovitexin and iso-orientin was found to give 100% conversion to the corresponding 8-C-glucoside.  相似文献   

2.
Antioxidant activity of fruit bodies of Laetiporus sulphureus (Bull.: Fr.) Murr. (Polyporales) obtained by the natural plantation growing method in Pribaikal'e (Irkutsk region) has been studied. It was determined that the ethyl acetate fraction of L. sulphureus, which was chromatographically separated into seven compounds identified as quercetin, kaempferol, (+)-catechin, p-coumaric, gallic, caffeic, and chlorogenic acids was characterized with more expressed antioxidant activity. All compounds were extracted from this basidiomycete species for the first time. The quantitative amount of the substances isolated from L. sulphureus was determined by HPLC. It was found that antioxidant activity of preparations obtained from L. sulphureus is conditioned by phenolic compounds.  相似文献   

3.
Acylated flavone C-glycosides from Cucumis sativus   总被引:3,自引:0,他引:3  
Leaves of Cucumis sativus plants treated with silicon and infected with Sphaerotheca fuliginea yielded five new acylated flavone C-glycosides identified as isovitexin 2"-O-(6"'-(E)-p-coumaroyl)glucoside (6), isovitexin 2"-O-(6"'-(E)-p-coumaroyl)glucoside-4'-O-glucoside (7), isovitexin 2"-O-(6"'-(E)-feruloyl)glucoside-4'-O-glucoside (11), isoscoparin 2"-O-(6"'-(E)-p-coumaroyl)glucoside (9), and isoscoparin 2"-O-(6"'-(E)-feruloyl)glucoside-4'-O-glucoside (12). The known flavone-glycosides isovitexin (1), saponarin (2), saponarin 4'-O-glucoside (3), vicenin-2 (4), apigenin 7-O-(6"-O-p-coumaroylglucoside) (5), isovitexin 2"-O-(6"'-(E)-feruloyl)glucoside (8) and isoscoparin 2"-O-(6"'-(E)-feruloyl)glucoside (10), were also identified in this plant material.  相似文献   

4.
The leaves of 5 fern species of the genusCyathea, i.e.C. fauriei, C. mertensiana, C. leichhardtiana, C. podophylla andC. hancockii, have been chemically analysed. The former 3 species have kaempferol 3-sophoroside (sophoraflavonoloside) and kaempferol 7-rhamnoglucoside as glycosidic components, and the latter 2 species contain kaempferol 3-galactoside (trifolin) and kaempferol 3-rhamnoglucoside (nicotiflorin). In addition, vitexin, orientin, kaempferol 3-glucoside (astragalin), kaempferol 3-rhamnoside (afzelin) and kaempferol 7-arabinoside are detected as common constituents in all the 5 species analysed.  相似文献   

5.
S-M Chung  J E Staub  J-F Chen 《Génome》2006,49(3):219-229
To investigate phylogenetic relationships in the genus Cucumis, 9 consensus chloroplast simple sequence repeat (ccSSR) primer pairs (ccSSR3, 9, 11, 13, 14, 17, 20, 21, and 23) were employed for DNA fragment length variation and 5 amplified fragments, ccSSR4, 12, 13, 19, and 20, were sequenced using total DNA from 13 accessions representing 7 African Cucumis species (x = 12), 3 Cucumis melo L. (x = 12) accessions, 2 Cucumis sativus L. (x = 7) accessions, and 1 Cucumis hystrix Chakr. (x = 12) accession. A Citrullus lanatus (Thunb.) Matsum. & Nakai (x = 11) accession was used as an outgroup. While fragment length analysis revealed the existence of 3 major species clusters (i.e., a group of African Cucumis species, a group composed of C. melo accessions, and a group containing C. sativus and C. hystrix species), sequence variation analysis identified 2 major species clusters (i.e., a group of African Cucumis species and a group composed of C. melo, C. sativus, and C. hystrix species). Comparative analysis using nuclear DNA (previous studies) and cpDNA sequence substitution data resulted in the placement of C. melo and C. sativus in different cluster groupings. Thus, both nuclear and cytoplasmic DNA should be employed and compared when a putative progenitor or specimens of an ancestral Cucumis species lineage is investigated. In addition, C. ficifolius (2x) and C. aculeatus (4x) of the African Cucumis species clustered together in this study. This result does not agree with reported isozyme analyses, but does agree with previously characterized chromosome homologies between these 2 species. Although African Cucumis species and C. hystrix do not share a close relationship, genetic affinities between C. sativus and C. hystrix are considerable. Combined evidence from previously published studies and data presented herein lend support to the hypothesis that C. hystrix is either a progenitor species of C. sativus or that they at least share a common ancestral lineage.  相似文献   

6.
Antioxidant activity of fruit bodies of Laetiporus sulphureus (Bull.: Fr.) Murr. (Polyporales) obtained by the natural plantation growing method in Pribaikal’e (Irkutsk region) has been studied. It was determined that the ethyl acetate fraction of L. sulphureus, which was chromatographically separated into seven compounds identified as quercetin, kaempferol, (+)-catechin, p-coumaric, gallic, caffeic, and chlorogenic acids was characterized with more expressed antioxidant activity. All compounds were extracted from this basidiomycete species for the first time. The quantitative amount of the substances isolated from L. sulphureus was determined by HPLC. It was found that antioxidant activity of preparations obtained from L. sulphureus is conditioned by phenolic compounds.  相似文献   

7.
A series of kaempferol derivatives have been identified in fronds of three parental species of the Appalachian Asplenium complex. Asplenium platyneuron is characterised by the presence of the 7-glucoside of kaempferol 3,4′-dimethyl ether and also contains kaempferol 3,7-diglucoside, free and with an aliphatic acyl attachment. By contrast, A. rhizophyllum contains a remarkable caffeoyl complex of kaempferol glycosides, which appears to be chromatographically homogenous. However, on deacylation, the complex yields caffeic acid and the 7-glucoside, 3,7-diglucoside, 3-sophoroside-7-glucoside and 7,4′-diglucoside of kaempferol. Asplenium montanum, in addition to having previously characterised glycosylxanthones, has two further kaempferol derivatives. It has been confirmed that these various species specific flavonoids are inherited in an additive fashion in three interspecific hybrids.  相似文献   

8.
From the needles of Taxus baccata the following flavonoids were isolated: 3-O-rutinosides quercetin, myricetin and kaempferol, 7-O-glucosides kaempferol and quercetin, kaempferol, quercetin, myricetin. The composition of flavonols and biflavones in some of the species of the genus Taxus, namely T. celebica, T. cuspidata, T. media and cultivar varieties T. baccata 'Aurea', T. baccata 'Aurea decora', T. baccata 'Elegantissima', T. baccata 'Fastigiata', T. baccata 'Pyramidalis', T. media 'Hatfieldii' were compared by HPLC separation.  相似文献   

9.
《Phytochemistry》1986,25(11):2591-2597
The sterol compositions of six Cucurbitaceae seeds, Cucurbita pepo, C. lagenaria, Citrullus lanatus, Cucumis sativus, C. melo and Luffa aegyptiaca, were examined by TLC, GLC, HPLC and m some cases by mass spectrometry and 1HNMR spectroscopy. Thirteen components were identified. They were codisterol, 25(27)-dehydroporiferasterol, clerosterol, isofucosterol, stigmasterol, campesterol, 22-dihydrobrassicasterol, sitosterol, 25(27)-dehydrofungisterol, 25(27)-dehydrochondrillasterol, 24β-ethyl-25(27)-dehydrolathosterol, avenasterol, spinasterol, 24ξ-methyllathosterol and 22-dihydrospinasterol. 24-Methylenecholesterol may also have been present. The Δ5-sterols were observed in all species. The pattern of sterols suggests the existence of four biosynthetic pathways operating from a 24(25)-dehydroprecursor. This work represents only the second time either codisterol or 25(27)-dehydrofungisterol has been isolated from a higher plant.  相似文献   

10.

Introduction

The plant species Ipomoea aquatica contains various bioactive constituents, e.g. phenols and flavonoids, which have several medical uses. All previous studies were executed in Asia; however, no reports are available from Africa, and the secondary metabolites of this plant species from Africa are still unknown.

Objective

The present study aims finding suitable conditions to identify the bioactive compounds from different fractions.

Methodology

Chromatographic fingerprint profiles of different fractions were developed using high‐performance liquid chromatography (HPLC) and then these conditions were transferred to thin‐layer chromatography (TLC). Subsequently, the chemical structure of some bioactive compounds was elucidated using ultra‐performance liquid chromatography‐quadrupole time of flight‐tandem mass spectrometry (UPLC‐QTOF‐MS) and liquid chromatography‐solid phase extraction‐nuclear magnetic resonance (LC‐SPE‐NMR) spectroscopy.

Results

The HPLC fingerprints, developed on two coupled Chromolith RP‐18e columns, using a gradient mobile phase (methanol/water/trifluoroacetic acid, 5:95:0.05, v/v/v), showed more peaks than the TLC profile. The TLC fingerprint allows the identification of the types of chemical constituents, e.g. flavonoids. Two flavonoids (nicotiflorin and ramnazin‐3‐O‐rutinoside) and two phenolic compounds (dihydroxybenzoic acid pentoside and di‐pentoside) were tentatively identified by QTOF‐MS, while NMR confirmed the structure of rutin and nicotiflorin.

Conclusion

The HPLC and TLC results showed that HPLC fingerprints give more and better separated peaks, but TLC helped in determining the class of the active compounds in some fractions. Bioactive constituents were identified as well using MS and NMR analyses. Two flavonoids and two phenolic compounds were tentatively identified in this species for the first time, to the best of our knowledge. Copyright © 2017 John Wiley & Sons, Ltd.  相似文献   

11.
The Chinese Pharmacopoeia indicates the use of field thistle (Cirsium setosum) and Japanese field thistle (C. japonicum) in the treatment of bleeding and inflammation. In the absence of an analytical method for the differentiation and analysis of these two species, TLC and HPLC-MS methods have been developed for this purpose. Both species could be readily distinguished by their flavonoid pattern as revealed by TLC on silica gel layers eluted with ethyl acetate:formic acid:acetic acid:water. The quantitative determination of four flavonoids, namely hispidulin-7-neohesperidoside, linarin, pectolinarin and luteolin, was possible using HPLC. Their optimum separation was achieved on a C12 column eluted with water and 0.025% trifluoroacetic acid in acetonitrile. HPLC-MS experiments were performed to confirm peak identity. In samples of C. japonicum, pectolinarin was the major flavonoid (0.32-2.00%), followed by linarin, hispidulin-7-neohesperidoside and luteolin; the total flavonoid content varied from 0.81 to 3.67%. In C. setosum only one flavonoid (linarin; 1.36-2.83%) was assignable. The HPLC method was validated for linearity, limit of detection (< or = 1.7 ng on-column), peak purity, repeatability (< or = 2.3%) and accuracy (recovery rates of spiked samples were between 99.2 and 101.6%).  相似文献   

12.
The flavonoids and xanthones in the leaves of Amorphophallus titanum, which has the largest inflorescence among all Araceous species, were surveyed. Eight C-glycosylflavones, five flavonols, one flavone O-glycoside and two xanthones were isolated and characterized as vitexin, isovitexin, orientin, isoorientin, schaftoside, isoschaftoside, vicenin-2 and lucenin-2 (C-glycosylflavones), kaempferol 3-O-robinobioside, 3-O-rutinoside and 3-O-rhamnosylarabinoside, and quercetin 3-O-robinobioside and 3-O-rutinoside (flavonols), luteolin 7-O-glucoside (flavone), and mangiferin and isomangiferin (xanthones). Although the inflorescence of this species has been surveyed for flavonoids, those of the leaves were reported for the first time.  相似文献   

13.
罗汉果叶中黄酮甙元的研究   总被引:10,自引:0,他引:10  
陈全斌  杨建香  义祥辉  程忠泉   《广西植物》2006,26(2):217-220
以罗汉果叶为原料提取出黄酮,黄酮经水解、溶剂萃取、柱层析等手段,得到高纯度甙元;经TLC、液相色谱、红外光谱、核磁共振法等分析手段进行结构鉴定,证实甙元分别为山奈酚、槲皮素。  相似文献   

14.
We have purified from human placenta a low molecular mass substance that inhibits cAMP-dependent protein kinase and activates protein kinase C. This protein kinase regulator was purified in three steps: (1) homogenizing placentas in chloroform/methanol and extracting the regulator into water; (2) eluting a strong anion exchange high performance liquid chromatography (HPLC) column with a quaternary gradient; and (3) eluting a reversed-phase HPLC column with a binary gradient. The regulator was found to be highly purified by HPLC, thin-layer chromatography (TLC) and laser desorption ionization mass spectrometry with a molecular mass of 703 Daltons by the latter procedure. The physical and biochemical properties of this protein kinase regulator suggest that it is a phospholipid but it did not co-elute by HPLC or by TLC with any of the known phospholipid activators of protein kinase C.  相似文献   

15.
Flavonoids were identified by PC and HPLC from the flowers of three cholla species and their known diploid and triploid hybrids. All the individuals examined produce quercetin 3-glucoside, quercetin 3-rutinoside and kaempferol 3-glucoside, which vary quantitatively among taxa.  相似文献   

16.
Cucumber (Cucumis sativus L.) roots were analyzed by HPLC and TLC for their levels of secondary metabolites upon inoculation with the arbuscular mycorrhizal fungus, Glomus caledonium. Three compounds in EtOAc extracts from the mycorrhizal roots showed significant increases six weeks after inoculation. These compounds were isolated by column chromatography and determined to be two novel triterpenes, 2beta-hydroxybryonolic acid (2beta,3beta-dihydroxy-D:C-friedoolean-8-en-29-oic acid) and 3beta-bryoferulic acid [3beta-O-trans-ferulyl-D:C-friedooleana-7,9(11)-diene-29-oic acid], and the known triterpene, bryonolic acid, by spectroscopic methods. Time-course experiments showed that the levels of the three terpenoids in cucumber roots were significantly increased by the application of a 53-microm sieving from a soil inoculum of the arbuscular mycorrhizal fungus containing soil microbes but no mycorrhizal fungi, and that mycorrhizal colonization further promoted the terpenoid accumulation. Inoculation with Glomus mosseae also enhanced the accumulation of the triterpenes, whereas no accumulation was observed by inoculating with the fungal pathogen, Fusarium oxysporum f. sp. cucumerinum. 2Beta-hydroxybryonolic acid was also isolated from the roots of melon and watermelon.  相似文献   

17.
24 species of Oenothera, representing 8 subgenera, were examined for their phenolics by TLC. Several phenolic acids, hydrolysable tannins, a quercetin-glucoside and galactosides of quercetin, kaempferol and myricetin were identified. In addition delphinidin and cyanidin were found.  相似文献   

18.
An HPLC method for the separation and analysis of arachidonic acid and eight phospholipid classes is described: phosphatidylglycerol, phosphatidylinositol, cardiolipin, phosphatidylserine, phosphatidylethanolamine, phosphatidylcholine, sphingomyelin, and 2-lysophosphatidylcholine. The separation is carried out at 60 degrees C on 2 cyanopropyl columns using a gradient of acetonitrile and 5 mM sodium acetate (pH 5.0). Cyanopropyl columns require a lower proportion of water in the mobile phase to elute the more polar phospholipids than other types of columns and are thus less prone to equilibration problems. The method is highly reproducible (average coefficient of variation for each retention time less than or equal to 3.5%) and permits analysis of peaks by phosphorus content. Data obtained by analyzing lipid extracts from rat alveolar macrophages prelabeled with [G-3H]-arachidonic acid were analyzed by this HPLC method and compared to standard analysis by TLC. There was a significant correlation between the radioactivity profiles obtained with the two chromatographic methods (HPLC versus TLC) by linear regression analysis [HPLC = 0.83 (TLC) + 3.58, n = 25, r = 0.95, P less than 0.001].  相似文献   

19.
Cytochalasin B (CB) was prepared by methanol extraction of dehydrated mold (Drechslera dematioidea) matte, reverse-phase C18 silica gel batch adsorption, selective elution with 1:1 (v/v) hexane:tetrahydrofuran (THF), crystallization, preparative TLC, and recrystallization. Unit gravity silica gel normal phase chromatography afforded additional CB. Yield per liter of medium was 300 mg of CB greater than 95% pure by NMR, HPLC (60:40 hexane:THF, Lichrosorb Si60 silica gel, 230 nm), and TLC. CB added exogenously to mouse organs at 1 and 5 micrograms/organ was recovered 70 to 100% by methanol extraction, adsorption to C18 silica gel Sep-Pak cartridges, elution with ethyl acetate, and analysis by TLC and/or HPLC. Limiting sensitivity (micrograms/extract) was 0.5 TLC; 1.0 HPLC. Quantitative extraction was confirmed with 3H-labeled CB. CB ip in mice at 50 mg/kg (LD10) distributed rapidly into liver, renal fat, kidney, intestines, mesentery, pancreas, spleen, and blood cells and was cleared from all but liver within 24 h. CB was below detectable levels in thymus, lymph nodes, heart, brain, bone marrow, and lungs. Cytochalasin A is fixed to tissues and not extractable. This work affords a source of CB in quantities permitting in vivo study, provides methods for extraction and analysis, and reveals the pharmacokinetics of ip bolus CB.  相似文献   

20.
Using 7,7,8,8-tetracyanoquinodimethane (TCNQ) as a new derivatization reagent for HPLC and TLC, novel methods are described to detect secondary amine-bearing antidepressants (paroxetine, desipramine, fluoxetine, nortriptyline, maprotiline). The HPLC method is sensitive enough to detect these drugs in plasma at therapeutic levels whereas the latter has potential to detect them in overdose or forensic cases. The methods are based on purple chromogens formed by the displacement reaction of the drugs with TCNQ. The resulting chromogens are directly separated by either reversed-phase HPLC on a C(18) column or TLC on silicagel plates. For HPLC, acetonitrile-water (60:40) was used as mobile phase, with detection at 567 nm and separation in 40 min. For TLC, three developing solvent systems were used. By HPLC, 36 ng ml(-1) spiked plasma concentration of the drugs gave easily detectable signals whereas by TLC, detection limits varied mostly between 240 and 480 ng ml(-1). The HPLC method was applied to real plasma samples. The methods described are simple and very selective; some metabolites of these antidepressants and a vast number of drugs do not interfere with detection.  相似文献   

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