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1.
Fossen T  Andersen ØM 《Phytochemistry》2003,62(8):1217-1220
Four anthocyanins with the same novel 4-substituted aglycone, carboxypyranocyanidin, have been isolated from acidified, methanolic extracts of the edible scales as well as from the dry outer scales of red onion, Allium cepa L. The structures of 1 and 2 were identified as the 3-O-beta-glucopyranoside and 3-O-(6"-O-malonyl-beta-glucopyranoside) of 5-carboxypyranocyanidin, respectively. This aglycone, 5-carboxy-2-(3,4-dihydroxyphenyl)-3,8-dihydroxy-pyrano[4,3,2-de]-1-benzopyrylium, is with exception of the substitution pattern on the phenyl ring similar to carboxypyranomalvidin (vitisidin A) recently isolated from red wines. In addition to 1 and 2, two analogues of 2 methylated at the terminal carboxyl group of the acyl moiety (3) or at the aglycone carboxyl (4), respectively, were also identified. These latter compounds are most probably formed by esterification of 2 with the solvent (acidified methanol) during the isolation process. The structures were elucidated by 2D NMR spectroscopy and LC-MS.  相似文献   

2.
The biomass production of Cymbopogon citratus shoots cultivated in bioreactors according to the temporary immersion (TIS) principle was assessed under different growth conditions. The effect of gassing with CO2-enriched air, reduced immersion frequency, vessel size and culture time on total phenolic and flavonoid content and free radical scavenging effect of the methanolic extracts was measured. From the TIS-culture of C. citratus, seven compounds were isolated and identified as caffeic acid (1), chlorogenic acid (2), neochlorogenic acid (3), p-hydroxybenzoic acid (4), p-hydroxybenzoic acid 3-O-beta-D-glucoside (5), glutamic acid (6) and luteolin 6-C-fucopyranoside (7). The occurrence of compounds 1-7 and their variability in C. citratus grown under different TIS conditions was determined by HPLC. The free radical scavenging effect of the methanolic extract and compounds was measured by the discoloration of the free radical 1,1-diphenyl-2-picrylhydrazyl (DPPH). The main metabolites in 6- and 8-week-old cultures, both in 5 and 10 1 vessels, were chlorogenic acid (2) (100-113 mg%) and neochlorogenic acid (3) (80-119 mg%), while in the cultures with CO2-enriched air and reduced immersion frequency the main compound detected in the extracts was glutamic acid (6) (400 and 670 mg% for the green and white biomass and 619 and 630 mg% for the green and white biomass, respectively). The most active compounds, as free radical scavengers, in the DPPH discoloration assay were caffeic acid (1), chlorogenic acid (2), neochlorogenic acid (3) and the flavonoid luteolin 6-C-fucopyranoside (7).  相似文献   

3.
Marine algae are rich sources ofbioactive compounds capable of harboring secondary metabolites which are structurally and biologically active. In our study, the methanolic extract of marine algae Caulerpa racemosa (green algae) was employed to determine the antibacterial and larvicidal activity. The antibacterial activity showed effective inhibition against five pathogenic bacteria. A significant zone size of 16 mm was observed for Pseudomonas aeruginosa. The methanolic extract of Caulerpa racemosa showed effective larvicidal activity against Culex tritaeniorhynchus and the histopathological studies revealed the rupture in mid gut of larvae. The bioactive compounds in the crude extract were further identified as 2-(-3-bromo-1-adamantyl) acetic acid methyl ester and Chola-5, 22- dien-3-ol by GC-MS. Hence the bioactive compounds obtained from the methanolic extracts could be used for the bactericidal and larvicidal activity which will overcome the harmful impact of synthetic insecticide on environment.  相似文献   

4.
A chemosystematic HPLC-UV and HPLC-MS investigation of New Zealand members of the Apiaceae was performed. Diterpenes were identified and quantified in methanolic extracts from subaerial parts of 28 taxa and 54 samples of Aciphylla, Anisotome, Apium, Gingidia, Lignocarpa, Oreomyrrhis, and Scandia. Six diterpenes (1-2, 4-7) and four polyacetylenes (8-11) were identified. The known compounds were the diterpenes anisotomenoic acid 1, anisotomene-1-ol 2, 16-acetoxyanisotomenoic acid 4 and anisotomene-1,12-diol 5; and the polyacetylenes falcarinol 8, falcarindiol 9, (+)-9(Z),17-octadecadiene-12,14-diyne-1,11,16-triol 10, and (+)-9(Z),17-octadecadiene-12,14-diyne-1,11,16-triol 1-acetate 11. New irregular diterpenes 13,14-dihydroanisotom-12E-ene-1,14-diol 6 and 14-methoxy-13,14-dihydroanisotom-12E-ene-1-ol 7 were isolated from A. haastii. Isomers of the new semi-synthetic diterpene 16-hydroxyanisotomenoic acid 3 were detected in extracts of Anisitone flexuosa. Structure elucidation was performed by HR mass spectrometry and 1D and 2D NMR spectroscopy. In crude extracts, compounds were identified by their HPLC retention times and their on-line HPLC-UV and MS spectra. Anisotomene diterpenes occurred in eight out of 16 species of the genus Anisotome, but were not detected in any of the other genera. In contrast, polyacetylenes were present in all the genera investigated.  相似文献   

5.
Antibacterial bromophenols from the marine red alga Rhodomela confervoides   总被引:8,自引:0,他引:8  
Xu N  Fan X  Yan X  Li X  Niu R  Tseng CK 《Phytochemistry》2003,62(8):1221-1224
Two bromophenols, together with three known compounds, were isolated from the methanolic extract of the marine alga, Rhodomela confervoides. By means of MS and NMR spectroscopic analyses, they were identified as 3-bromo-4-[2,3-dibromo-4,5-dihydroxyphenyl] methyl-5-(hydroxymethyl) 1,2-benzenediol (1) and 3-bromo-4-[2,3-dibromo-4,5-dihydroxyphenyl] methyl-5- (ethoxymethyl) 1,2-benzenediol (2). Three known compounds were also isolated, namely 3-bromo-4-[2,3-dibromo-4,5-dihydroxyphenyl] methyl-5-(methoxymethyl) 1,2-benzenediol (3), 4,4'- methylenebis [5,6-dibromo-1,2-benzenediol] (4) and bis (2,3-dibromo-4,5-dihydroxybenzyl) ether (5). Compound 5 was the most active against five strains of bacteria with the MIC less than 70 microg/ml, while compounds 2, 3 and 4 exhibited moderate activity.  相似文献   

6.
Three C-17 diacetylenic compounds (1-3), one monoterpenoid (4), seven ceramides (leucoceramides A-G, 5a-g), six cerebrosides (leucocerebrosides A-F, 6a-f) and nine known compounds were isolated from the methanolic extract of Hydrocotyle leucocephala. Their structures were established by spectroscopic methods. The isolated compounds 1-3, 5a-g, 6a-f and 7 were shown to be active in the lipopolysaccharide (LPS) induced cytokine production assay for IL-10, IL-12, and TNF-alpha.  相似文献   

7.
三丫苦的化学成分研究   总被引:1,自引:0,他引:1  
采用硅胶柱层析从三丫苦的乙酸乙酯萃取物中分离得到6种化合物,经波谱分析鉴定为4,7-二甲氧基呋喃喹啉生物碱(1)、顺式-3,4,5-三羟基-6-乙酰基-7-甲氧基-2,2-二甲基色烷(2)、3-羟基-4-乙氧基-5,7-二甲氧基-6-乙酰-2,2-二甲基色烷(3)、3,5-二羟基-4-乙氧基-6-乙酰基-7-甲氧基-2,2-二甲基色烷(4)、异吴茱萸酮酚(5)和异吴茱萸酮酚甲醚(6)。所有化合物均首次从该植物的根部分离得到。  相似文献   

8.
In our screening program for new photosensitizers from Malaysian biodiversity for photodynamic therapy (PDT) of cancer, MeOH extracts of ten terrestrial plants from Cameron Highlands in Pahang, Peninsular Malaysia, were tested. In a short-term 3-(4,5-dimethylthiazol-2-yl)-2,5-diphenyl-2H-tetrazolium bromide (MTT) assay, 20 μg/ml each of these extracts were incubated in a pro-myelocytic leukemia cell-line, HL60, with or without irradiation with 9.6 J/cm(2) of a broad spectrum light. Three samples, Labisia longistyla, Dichroa febrifuga, and Piper penangense, were photocytotoxic by having at least twofold lower cell viability when irradiated compared to the unirradiated assay. The extract of the leaves of Piper penangense, a shrub belonging to the family Piperaceae and widely distributed in the tropical and subtropical regions in the world, was subsequently subjected to bioassay-guided fractionation using standard chromatography methods. Eight derivatives of pheophorbide-a and -b were identified from the fractions that exhibited strong photocytotoxicity. By spectroscopic analysis, these compounds were identified as pheophorbide-a methyl ester (1), (R,S)-13(2) -hydroxypheophorbide-a methyl ester (2 and 3), pheophorbide-b methyl ester (4), 13(2) -hydroxypheophorbide-b methyl ester (5), 15(2) -hydroxylactone pheophorbide-a methyl ester (6), 15(2) -methoxylactone pheophorbide-a methyl ester (7), 15(2) -methoxylactone pheophorbide-b methyl ester (8).  相似文献   

9.
丽江蚤缀的化学成分   总被引:5,自引:0,他引:5  
常忠义  龚维红 《广西植物》2005,25(3):278-280
利用DiaionHP20及硅胶柱层析进行化合物的分离,从乙酸乙酯萃取部位分离得到了8个化合物,借助多种光谱技术进行结构鉴定分别鉴定为E对甲氧基肉桂酸(pEMethoxycinnamicacid)(Ⅰ),Z对甲氧基肉桂酸甲酯(3(4Methoxyphenyl)2Zpropenoicacidmethylester)(Ⅱ),Z对甲氧基肉桂酸(pZMethoxycinnamicacid)(Ⅲ),E对羟基肉桂酸甲酯(pEHedroxycinnamicacidmethylester)(Ⅳ),2,4,6,4′fourhydroxydihydrochalcone(Ⅴ),5,7,4′三羟基3′,5′二甲氧基黄酮(Ⅵ),β谷甾醇(βSidosterol)(Ⅶ),胡萝卜苷(Daucosterol)(Ⅷ)。所有化合物均为已知化合物,并首次从该植物中分得。  相似文献   

10.
Eight limonoids, anthothecanolide (1), 3-O-acetylanthothecanolide (2), 2,3-di-O-acetylanthothecanolide (3), 6R,8alpha-dihydroxycarapin (4), 3beta-acetoxy-3-deoxo-6R-hydroxycarapin (5), methyl angolensate, methyl 6-hydroxyangolensate and khayalactone together with sitosterol glucoside, have been isolated from the extracts of the stem bark of Khaya anthotheca. Compounds 1-4 are described for the first time. Their structures were established by analysis of the high-field NMR and MS data. The structure of compound 4 was confirmed by a single crystal X-ray structure analysis.  相似文献   

11.
The antimicrobial activity of samples of Northern Argentine propolis (Tucumán, Santiago del Estero and Chaco) against phytopathogenic bacteria was assessed and the most active samples were identified. Minimal inhibitory concentration (MIC) values were determined by agar macrodilution and broth microdilution assays. Strong antibacterial activity was detected against Erwinia carotovora spp carotovora CECT 225, Pseudomonas syringae pvar tomato CECT 126, Pseudomonas corrugata CECT 124 and Xanthomonas campestris pvar vesicatoria CECT 792. The most active propolis extract (Tucumán, T1) was selected to bioguide isolation and identified for antimicrobial compound (2',4'-dihydroxychalcone). The antibacterial chalcone was more active than the propolis ethanolic extract (MIC values of 0.5-1 μg ml(-1) and 9.5-15 μg ml(-1), respectively). Phytotoxicity assays were realized and the propolis extracts did not retard germination of lettuce seeds or the growth of onion roots. Propolis solutions applied as sprays on tomato fruits infected with P. syringae reduced the severity of disease. Application of the Argentine propolis extracts diluted with water may be promising for the management of post harvest diseases of fruits.  相似文献   

12.
From a methanolic extract of the leaves of Croton stipuliformis, three ent-3,4-seco-labdanes (1-3) and an ent-labdane (4) together with the known compounds 6-hydroxynidorellol (5), maravuic acid, and sitosterol were isolated and identified from their spectroscopic data. The absolute stereochemistry of compound 4 was determined by application of Mosher's method in the NMR tube.  相似文献   

13.
Bioassay-guided fractionation of two phytotoxic extracts (a CH(2)Cl(2)-MeOH (1:1) and an aqueous) prepared from the aerial parts of Hofmeisteria schaffneri led to isolation of thymol analogs 3-5, along with seven known compounds, 1, 2 and 6-10. Compounds 3-5 were identified by spectroscopic methods as 1,4-bis(2'-hydroxy-4'-methylphenyl)butane-1,4-dione (3), 2-isopropyl-5-methylphenyl (2Z)-2-methylbut-2-enoate (4) and 2-hydroxy-2-(2-hydroxy-4-methylphenyl)propane-1,3-diyl (2Z,2'Z)bis(2-methylbut-2-enoate) (5) and designated trivial names of hofmeisterins II-IV, respectively. Their conformational behavior was also studied by molecular modeling using density functional theory calculations at the B3LYP/DGDZVP level. Compounds 1-4 and 6-10 significantly inhibited radicle growth of seedlings of Amaranthus hypochondriacus and Echinochloa crus-galli in the Petri dish bioassay with IC(50)'s10(-4)M. Furthermore, the northymol analog 3 provoked significant bleaching of seedlings of A. hypochondriacus. However, none of the isolates affected either seedling growth or germination of Medicago sativa.  相似文献   

14.
Using techniques previously employed to identify ginger constituents in fresh organically grown Hawaiian white and yellow ginger varieties, partially purified fractions derived from the silica gel column chromatography and HPLC of a methylene chloride extract of commercially processed dry ginger, Zingiber officinale Roscoe, Zingiberaceae, which demonstrated remarkable anti-inflammatory activity, were investigated by gas chromatography-mass spectrometry. In all, 115 compounds were identified, 88 with retention times (R(t)) >21 min and 27 with <21 min. Of those 88 compounds, 45 were previously reported by us from fresh ginger, 12 are cited elsewhere in the literature and the rest (31) are new: methyl [8]-paradol, methyl [6]-isogingerol, methyl [4]-shogaol, [6]-isoshogaol, two 6-hydroxy-[n]-shogaols (n=8 and 10), 6-dehydro-[6]-gingerol, three 5-methoxy-[n]-gingerols (n=4, 8 and 10), 3-acetoxy-[4]-gingerdiol, 5-acetoxy-[6]-gingerdiol (stereoisomer), diacetoxy-[8]-gingerdiol, methyl diacetoxy-[8]-gingerdiol, 6-(4'-hydroxy-3'-methoxyphenyl)-2-nonyl-2-hydroxytetrahydropyran, 3-acetoxydihydro-[6]-paradol methyl ether, 1-(4'-hydroxy-3'-methoxyphenyl)-2-nonadecen-1-one and its methyl ether derivative, 1,7-bis-(4'-hydroxy-3'-methoxyphenyl)-5-methoxyheptan-3-one, 1,7-bis-(4'-hydroxy-3'-methoxyphenyl)-3-hydroxy-5-acetoxyheptane, acetoxy-3-dihydrodemethoxy-[6]-shogaol, 5-acetoxy-3-deoxy-[6]-gingerol, 1-hydroxy-[6]-paradol, (2E)-geranial acetals of [4]- and [6]-gingerdiols, (2Z)-neral acetal of [6]-gingerdiol, acetaldehyde acetal of [6]-gingerdiol, 1-(4-hydroxy-3-methoxyphenyl)-2,4-dehydro-6-decanone and the cyclic methyl orthoesters of [6]- and [10]-gingerdiols. Of the 27 R(t)<21 min compounds, we had found 5 from fresh ginger, 20 others were found elsewhere in the literature, and two are new: 5-(4'-hydroxy-3'-methoxyphenyl)-pent-2-en-1-al and 5-(4'-hydroxy-3'-methoxyphenyl)-3-hydroxy-1-pentanal. Most of the short R(t) compounds are probably formed by thermal degradation during GC (which mimics cooking) and/or commercial drying. The concentrations of gingerols, the major constituents of fresh ginger, were reduced slightly in dry ginger, while the concentrations of shogaols, the major gingerol dehydration products, increased.  相似文献   

15.
Anti-inflammatory phytocompounds from Crateva adansonii DC leaf extracts were identified by GCMS analysis and its anti-inflammatory potential was evaluated by in silico molecular docking study against inflammatory molecular targets. Three different (Aqueous, Methanol and Petroleum ether) dried leaf extracts of Crateva adansonii were obtained from soxhlet extraction method. Preliminary phytoconstituents analysis of three different leaf extracts of C. adansonii confirmed the presence of various major classes of bioactive phytoconstituents such as polyphenols (tannins and flavonoids), steroids, alkaloid, coumarin, carbohydrate and terpenoids. Among three leaf extracts, methanolic leaf extract possess highest total phenolic content of 77?±?1.65?µg gallic acid equivalent (GAE)/g of dry weight of leaf extract, subsequently methanolic leaf extract also shows maximal in vitro antioxidant activity (DPPH scavenging activity) of 71.22?±?1.32% among three different leaf extracts. GC–MS analysis of petroleum ether leaf extract revealed the presence of nine phytocompounds representing 95.43% peak area percentage, among nine identified phytocompounds three phytocompounds of C. adansonii possess anti-inflammatory property namely phytol, 1-Hexyl-2-Nitrohexane and 2-Isopropyl-5-Methylcyclohexyl 3-(1-(4-Chlorophenyl)-3-Oxobutyl)-Coumarin-4-Yl Carbonate were chosen for in silico molecular docking study against four inflammatory receptor targets (COX-2, TNFα, IL-1β and IL-6) and they shows less binding energy with highest docking score ranging from ?15.9500 to 5.0869. The present study substantially indicated and proven that anti-inflammatory potential of phytocompounds from C. adansonii leaf extracts which can be exploited for commercial designing of novel anti-inflammatory drug to treat various inflammatory disorders.  相似文献   

16.
Effects of Welsh onion extracts on human platelet function in vitro   总被引:3,自引:0,他引:3  
Chen JH  Chen HI  Wang JS  Tsai SJ  Jen CJ 《Life sciences》2000,66(17):1571-1579
Welsh onion has been consumed for prevention of cardiovascular disorders. However, its underlying mechanisms are still unclear. This study investigated whether Welsh onion extracts can alter human platelet function (ie, platelet adhesion, aggregation, and thromboxane release). To clarify the underlying mechanisms, we also measured the intracellular calcium ([Ca2+]i) and cyclic nucleotide levels in platelets. Our results showed that 1) boiled extracts directly induced platelet aggregation in a dose-dependent manner; 2) raw extracts inhibited platelet adhesion and ADP-evoked platelet aggregation, while boiled extracts enhanced them; 3) raw green extract suppressed ADP-stimulated platelet [Ca2+]i elevation and thromboxane production, whereas boiled green extract enhanced them; 4) raw green extract elevated platelet cAMP level, whereas boiled green extract had no effect on cAMP level. Furthermore, the boiled green extract, but not the raw extract, induced pronounced platelet morphological changes. In conclusion, raw extracts of Welsh onion inhibit platelet function in vitro while boiled extracts activate platelets.  相似文献   

17.
A Glu–Phe (EF) was isolated from onion (Allium cepa L. cv. Sunpower). The chemical structure of EF was determined by nuclear magnetic resonance and electrospray ionization–mass (ESI?MS) spectroscopy. We showed that EF reduced lipid accumulation in mouse hepatocytes by inhibiting the expression of sterol regulatory element-binding protein-1c (SREBP–1c) and its lipogenic target genes. We also found that AMP-activated protein kinase (AMPK) was required for the inhibitory effect of EF on lipid accumulation in mouse hepatocytes. Furthermore, EF was qualified in nine onion cultivars by selective multiple reaction-monitoring detection of liquid chromatography–ESI?MS. These results suggest that EF could contribute to the beneficial effect of onion supplement in maintaining hepatic lipid homeostasis.  相似文献   

18.
Ge F  Ke C  Tang W  Yang X  Tang C  Qin G  Xu R  Li T  Chen X  Zuo J  Ye Y 《Phytochemical analysis : PCA》2007,18(3):213-218
Two chlorogenic acids and five chlorogenic acid derivatives were simultaneously separated and purified from Stemona japonica by preparative high-performance liquid chromatography. Five of the collected compounds were over 95% pure while the other two compounds were over 90% pure. Their structures were elucidated as 3-O-feruloylquinic acid (1), 4-O-feruloylquinic acid (2), methyl 3-O-feruloylquinate (3), methyl 5-O-caffeyolquinate (4), methyl 4-O-feruloylquinate (5), ethyl 3-O-feruloylquinate (6) and the new compound ethyl 4-O-feruloylquinate (7) by UV, NMR and ESI-MS. All compounds were obtained from Stemona species for the first time, however compounds 6 and 7 are believed to be artefacts from the ethanol extraction. The anti-AIV (H5N1) activities were evaluated by Neutral Red uptake assay. Compounds 3 and 4 exerted moderate inhibitory effect against AIV (H5N1) in vitro.  相似文献   

19.
From the polar portion of the methanolic extract of the fruit of anise (Pimpinella anisum L.), which has been used as a spice and medicine since antiquity, four aromatic compound glucosides, an alkyl glucoside and a glucide were isolated together with 24 known compounds. The structures of the new compounds were clarified as (E)-3-hydroxyanethole beta-D-glucopyranoside, (E)-1'-(2-hydroxy-5-methoxyphenyl)propane beta-D-glucopyranoside, 3-hydroxyestragole beta-D-glucopyranoside, methyl syringate 4-O-beta-D-glucopyranoside, hexane-1,5-diol 1-O-beta-D-glucopyranoside and 1-deoxy-L-erythritol 3-O-beta-D-glucopyranoside by spectral investigation.  相似文献   

20.
Gibberellins A1, A3, A4 and A7 were identified by combined gas chromatography mass spectrometry (GC-MS) in leaf and stem tissues of 17-day-old seedlings of wheat ( Triticum aestivum L. ), cvs Siete Cerros (semi-dwarf, Rht1) and Møystad (tall), of F1, hybrids from the cross Møystad × Siete Cerros and of 2 selected lines from the cross Møystad x Sonora 64 (Rht1 and Rht2). GA, and GA, were identified by full scan mass spectra separately in all 5 extracts, GA4 and GA7, were identified by selected ion monitoring in a bulked fraction. About 90% of the biological activity (Tan-ginbozu dwarf rice bioassay) in all 5 extracts was due to the GA1/GA3-fraction.  相似文献   

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