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1.
Major dicaffeoylquinic acids from Artemisia vulgaris. 总被引：1，自引：0，他引：1
The two major caffeoylquinic acids, 3,5-di-O-caffeoylquinic acid and 1,5-di-O-caffeoylquinic acid, were new-isolated from the flowering tops of Artemisia vulgaris (yield 2.0% and 0.3% on dry weight, respectively) and characterized by spectroscopic analysis. 相似文献
2.
Ethanolic extracts of diploid Artemisia dracunculus L. (wild tarragon) from populations in the U.S., and polyploid tarragon from a variety of sources, were screened for the anti-diabetic compounds davidigenin; sakuranetin; 2’,4’-dihydroxy-4-methoxydihydrochalcone; 4,5-di-O-caffeoylquinic acid; 5-O-caffeoylquinic acid and 6-demethoxycapillarisin using LC-MS. Only decaploid plants contained all six target compounds and were the only plants that contained davidigenin and 2,4-dihydroxy-4-methoxydihydrochalcone. These results exhibit the importance of germplasm selection and provenance when studying plants for medicinal activity. Relying only on the “right species” for consistent medicinal activities may not be sufficient, as intraspecific variation may be highly significant. 相似文献
3.
《Fitoterapia》2014
The phytochemical investigation of natural products of Gynura divaricata led to the isolation of eleven caffeoylquinic acid derivatives. They were characterized by spectrometric methods as 5-O-caffeoylquinic acid (1), 5-O-p-coumaroylquinic acid (2), 5-O-feruloylquinic acid (3), methyl 5-O-caffeoylquinate (4), 3,4-dicaffeoylquinic acid (5), 3,5-dicaffeoylquinic acid (6), 4,5-dicaffeoylquinic acid (7), methyl 3,4-dicaffeoylquinate (8), methyl 3,5-dicaffeoylquinate (9), methyl 4,5-dicaffeoylquinate (10) and ethyl 4,5-dicaffeoylquinate (11). The individual compounds were screened for the inhibition of yeast α-glucosidase and Protein Tyrosine Phosphatase 1B (PTP1B) using in vitro assays. Among the isolated compounds, 3,4-dicaffeoylquinic acid (5), 4,5-dicaffeoylquinic acid (7), methyl 3,4-dicaffeoylquinate (8) and methyl 4,5-dicaffeoylquinate (10) exhibited significant inhibitory activities against α-glucosidase. In addition, 5-O-p-coumaroylquinic acid (2), 3,5-dicaffeoylquinic acid (6) and 4,5-dicaffeoylquinic acid (7) had considerable inhibitory effect against PTP1B. Based on these findings, the caffeoylquinic acid derivatives were deduced to be potentially responsible for the anti-diabetic activity of G. divaricata. The preliminary structure–activity relationship study suggests that the number and positioning of caffeoyl groups in the quinic acid derivatives are important for both α-glucosidase and PTP1B inhibitory potency. Moreover, the corresponding methyl esters of some dicaffeoylquinic acids have enhanced inhibitory activity against yeast α-glucosidase. 相似文献
4.
Phenolic compounds in seven South American Ilex species. 总被引：4，自引：0，他引：4
Ilex paraguariensis (common name: 'mate' or 'yerba mate') is used for the preparation of the most popular tea-like beverage of South America. Choleretic, hypocholesteremic, antioxidant, hepatoprotective and bitter taste properties of mate are attributed to the phenolic constituents of the leaves. I. paraguariensis has seven local congeneric substitutes or adulterants: I. brevicuspis; I. theezans; I. microdonta; I. dumosa var. dumosa; I. taubertiana; I. pseudobuxus; I. integerrima; and I. argentina. An HPLC method using UV with Photodiode Array Detector was developed for the identification and quantification of caffeoyl derivatives (caffeic acid, chlorogenic acid, 3,4-dicaffeoylquinic acid, 3,5-dicaffeoylquinic acid and 4,5-dicaffeoylquinic acid) and flavonoids (quercetin, rutin and kaempferol) in these species. I. paraguariensis showed a higher content of flavonoids and caffeoyl derivatives than the other assayed species. 相似文献
5.
One new compound, 4-hydroxy-4a,7-dimethoxy-4,4a-dihydrodibenzo-p-dioxin-2(3H)-one (1), was isolated from the aerial parts of the hybrid Hypericum x ‘Hidcote’, together with 8 known compounds: caryophyllene-4,5-epoxide, quercetin, quercitrin, quercetin-3-O-β-D-galactopyranoside, epicatechin, betulinic acid methyl ester, β-sitosterol and β-sitosterol glucoside. The structure of the new compound, as well as its absolute configuration, was established by means of spectroscopic data analyses, including 2D NMR spectroscopy and X-ray structural analysis. 相似文献
6.
There has been a mass mortality of oak trees in the area along the coast of the Japan Sea. This phenomenon is caused by the ambrosia beetle Platypus quercivorus, which carries the ambrosia fungus Raffaelea quercivora. Extractives of a necrotic brownish coloration formed in the infected sapwood of Quercus crispula were investigated. The methanol extract of the damaged sapwood of Q. crispula was concentrated in vacuo and centrifuged to yield precipitates and the supernatant. The precipitates were subjected to Sephadex LH-20 column chromatography and preparative HPLC to describe a novel ellagic acid derivative (1). The 10 % methanol water-soluble part of the supernatant was subjected to medium-pressure ODS column chromatography and preparative HPLC, respectively, to analyze a known lignan (2). Sulfuric acid hydrolysis of (1) yielded an ellagic acid and a gallic acid. NMR and LC-TOF/MS indicated that an ellagic acid and a gallic acid bonded to a xylose with glycosidic and ester bonds, respectively. Compound (1) was identified as 4,5-dihydroxy-6-(3,7,8–trihydroxy-5,10-dihydro–chromeno[5,4,3-cde]chromen-2-yloxy)-tetrahydro-pyran-3-yl ester, and compound (2) was identified as (–)-lyoniresinol. The presence of (–)-lyoniresinol from damaged sapwood indicated that infection of R. quercivora may cause the formation of a pseudo-heartwood in the sapwood of Q. crispula. 相似文献
7.
A new germacranolide has been isolated from the aerial parts of Artemisia pallens and the structure was established as 4,5 beta-epoxy-10 beta-hydroxy-1-en-3-one-trans-germacran-6 alpha,12-olide (1) by comparison with its 10 alpha-epimer isolated from the same plant. 相似文献
8.
Effects of Pouteria cambodiana extracts on in vitro immunomodulatory activity of mouse immune system
Immunomodulatory activity of water and acetone extracts of stem bark of Pouteria cambodiana was examined on murine macrophage phagocytosis [nitroblue tetrazolium (NBT) dye reduction and lysosomal enzyme activity] and proliferation of splenocytes and bone marrow cells by 3-(4,5-dimethylthiazole-2-yl)-2,5-diphenyltetrazolium bromide (MTT) assay with and without lipopolysaccharide (LPS) or pokeweed mitogen (PWM). Both aqueous and acetone extracts presented immunomodulatory activity without clear dose response relationship. 相似文献
9.
《Fitoterapia》1999,70(2):144-147
Two new piperidinamide dimers have been isolated from the leaves and immature buds of Piper peepuloides and their structures established by spectral analysis as cyclobutane-2-(1,3-benzodioxol-5-methoxy-6-yl)-4-(1,3-benzodioxol-4,5-dimethoxy-6-yl)-1,3-dicarboxapiperidide (1) and cyclobutane-2,4-bis-(1,3-benzodioxol-5-methoxy-6-yl)-1,3-dicarboxapiperidide (2). 相似文献
10.
Fechine IM Tavares JF da Silva MS Barbosa-Filho JM de Fátima Agra M da-Cunha EV 《Fitoterapia》2003,74(1-2):29-33
The stem and roots of Hornschuchia obliqua provided two new alkaloids, 4,5-didehydroguadiscine and demethoxyguadiscine. Four known alkaloids, roemerine, guadiscine, liriodenine and cleistopholine were also isolated. The structures of the novel compounds were elucidated by spectroscopic analysis, including 2D NMR and MS. 相似文献
11.
Three new eudesmanoids have been isolated from Sphaeranthus indicus and their structures were established as 11alpha,13-dihydro-3alpha,7alpha-dihydroxy-4,5-epoxy-6beta,7-eudesmanolide, 11alpha,13-dihydro-7alpha-acetoxy-3beta-hydroxy-6beta,7-eudesm-4-enolide and 3-keto-beta-eudesmol by comparison of spectral data with those of other 7alpha-hydroxyeudesmanolides. 相似文献
12.
Ankita Hazarika 《Wood material science & engineering》2017,12(1):24-39
Wood polymer nanocomposites (WPNCs) based on nano-ZnO and nanoclay were prepared by impregnation of melamine formaldehyde–furfuryl alcohol copolymer, 1,3-dimethylol-4,5-dihydroxyethyleneurea (DMDHEU), a cross-linking agent and a renewable polymer obtained as a gum from the plant Moringa oleifera under vacuum condition. Fourier transform infrared spectroscopy (FTIR) and X-ray diffractometry (XRD) studies were employed for the characterization of modified ZnO and WPNCs. The change in crystallinity index (CrI) value of the cellulose in wood and the distribution of ZnO nanoparticles in composites were determined using FTIR and XRD. Scanning electron microscopy and Transmission electron microscopy showed the presence of nanoparticles and nanoclay in the cell lumen or cell wall of wood. An enhanced UV resistance property was shown by the treated wood samples as judged by lower weight loss, carbonyl index, lignin index, cellulose CrI values, and mechanical property loss compared to the untreated wood samples. Wood polymer composites treated with 3 phr each of nanoclay, ZnO, and the plant gum showed an improvement in mechanical properties, flame-retarding properties, thermal stability, and lower water uptake capacity. 相似文献
13.
Chemical investigation on the seeds of Vitex negundo has afforded a new furan-containing sesquiterpenoid, negunfurol (1), a new norlabdane-type diterpenoid, negundoal (2), and two new norursane-type triterpenoids, negundonorins A (3) and B (4), together with two know compounds, 3-formyl-4,5-dimethyl-8-oxo-5H-6,7-dihydronaphtho[2,3-b]furan (5) and 3-epi-corosolic acid (6). Their structures and configurations were elucidated by detailed spectroscopic analyses on the basis of NMR, IR, and MS data. Compound 3 was strongly cytotoxic against ZR-75-30 cell line with IC50 value of 0.56 ± 0.19 μg/mL, whereas compound 1 was most active against HL-60 cell line with IC50 value of 0.94 ± 0.26 μg/mL. 相似文献
14.
Dr. G. Zimmermann 《Journal of pest science》1980,53(5):69-72
The entomopathogenic fungusPaecilomyces tenuipes was isolated from dead noctuid pupae the identification of which was impossible. Some remarks are given on the morphology of this fungus rarely occurring in our regions. Besides the conspicuous synnemata and the oblong oval conidia (6,0–10,0×2,0–3,8 μm from culture, 4,5–7,5 ×2,0–2,5 μm from infected larvae) brown coloured and thick-walled appressoria were formed on glass surfaces. Pathogenicity tests showed thatP. tenuipes can infect as well larvae ofMamestra brassicae andAgrotis segetum as pupae ofM. brassicae andAutographa gamma. The formation of a perfect state was never observed. 相似文献
15.
A new γ-lactone coumarin, named as excavarin-A, showing antifungal activity was isolated from the leaves of Clausena excavata by bioassay guided fractionation method. The structure was elucidated by spectroscopic data analysis and identified as 7((2E)-4(4,5-dihydro-3-methylene-2-oxo-5-furanyl)-3-methylbut-2-enyloxy) coumarin. Minimum inhibitory concentration (MIC) was determined against fifteen fungal strains pathogenic against plants and human. The least MIC was recorded against the human pathogen, Candida tropicalis and the plant pathogens Rhizoctonia solani and Sclerotinia sclerotiorum. Antifungal activities against the human pathogens, Aspergillus fumigatus and Mucor circinelloides and plant pathogens, Colletotrichum gloeosporioides, Lasiodiplodia theobromae, Fusarium oxysporum and Rhizopus stolonifer were stronger than that of the standard antimicrobials. 相似文献
16.
Thechemicalconstitutionsoftheextractivevaryquitindifferentfamily,genusandspecies.ThisVariancecanbeidentifvedmucheasierthanthevariancesofcollulose,semicolluloseand1ignin.Thusthestudyofchemicalconstitutionsofextractiveisanimportantbranchofphytochemistryandchemicalplanttaxonomy.TetracentronSinenseOliveisaspecialbroad-leavedspecies.Therearetracheidsbutnovessel.Bothcharactersofbroad-leavedandconiferspeciespresentinonespecies-Thusthestudyofchemicalconstitutionsoftheextractivefromthisspeciesisquite… 相似文献
17.
The wood powder ofTetracentron Sinense Olive was extracted with the benzene and alcohol (2:1 v/v). Then, the extractive is analyzed in Gc and Gc-Ms. Twenty chemical
constitutions of the extractive are separated and identified, which are as follows: calamenene; 2.6,10-trimethyldihexyl; 3-methoxybenzaldehyde;
Methyl-4-methox-ybenzoate; 4-methoxyphenylacetone; 3.4-dimethoxybenzaldehyde; 3.4-dimethoxyhypnone; methyl-3.4-dimethoxybenzoate; Methyl-4-methoxyphenylacrylate;
4,4′-dimethoxycabonyl-diphenylethane; Methyl-3, 4,5-erimethoxybenzoate; Methyl-3.4-dimethoxyphenylacrylate; Methyl-myristate;
Methyl-palmate; Methyl-zoomarate; Methyl-stearate; Methyl-oleate; Methyl-arachidate; Methyl-behenate; Dimethylazelate. 相似文献
18.
沙枣(Elaeagnus angustifolia)也叫银柳、香柳、桂香柳,与沙棘同属胡颓子科,常绿灌木,主产于西北地区,分布在新疆、甘肃、青海、内蒙古西部等与沙漠接壤的典型大漠干旱或戈壁滩上.其树皮、果实和花均可用于治疗风寒咳嗽、痢疾腹泻等疾病(江苏新医学院中药大辞典编写组,1977). 相似文献
19.
Inhibition of Trypanosoma cruzi growth by medical plant extracts 总被引：4，自引：0，他引：4
Schinella GR Tournier HA Prieto JM Ríos JL Buschiazzo H Zaidenberg A 《Fitoterapia》2002,73(7-8):569-575
This study describes the screening of extracts obtained from 18 plants and two fungi used in the Chinese and Mediterranean traditional medicines on epimastigote forms of Trypanosoma cruzi. The extracts were tested against epimastigote of T. cruzi Bra C15C2 clone in vitro at 27 degrees C and at a concentration of 250 microg/ml in axenic culture. Angelica dahurica, A. pubescens, A. sinensis, Astragalus membranaceus, Coptis chinensis, Haplophyllum hispanicum, Phellodendron amurense, Poria cocos, Ranunculus sceleratus and Scutellaria baicalensis showed significant effects against the parasite with a percentage of growth inhibition between 20 and 100%. C. chinensis and R. sceleratus showed the greatest activity with IC(50) values of 1.7 microg/ml for C. chinensis and 10.7 microg/ml for R. sceleratus. These activities are greater than that of allopurinol. C. chinesis and R. sceleratus extracts did not show cytotoxic effects on rat polimorphonuclear cells using 3-(4,5-dimethylthiazol-2-yl)-2,5-diphenyl tetrazolium bromide and lactic dehydrogenase assays. These results allowed us to suggest that R. sceleratus and C. chinensis could be a source of new compounds clinically active against T. cruzi. 相似文献
20.
山杏叶桦木酸、齐墩果酸和熊果酸的研究 总被引：1，自引：0，他引：1
我国山杏资源十分丰富,是绿化荒山的优良树种。采用HydersirBDSC18色谱柱（150×4．6mm,5μm）,流动相体积比为90：10的0．3‰硫酸甲醇溶液一3‰硫酸水溶液,检测波长210nm,建立了山杏叶中三萜酸测定的高效液相色谱法。结果表明：桦木酸、齐墩果酸与熊果酸的浓度在30～2000μg／mL（r桦=0．9971,r齐=0．9986,r熊=0．9978）范围内与色谱峰面积呈良好线性关系;平均加标回收率分别为99．9％、101．1％和98．9％。以山杏叶为材料,采用高效液相色谱法和紫外可见分光光度法分别对山杏叶中的三萜酸成分进行分析,结果表明,山杏叶富含三萜酸,落叶期山杏叶中总三萜酸（17078#g／g）、桦木酸（1842μg／g）、齐墩果酸（2536μg／g）和熊果酸（5706μg／g）含量均高于非落叶期。本研究首次建立了山杏叶中桦木酸、齐墩果酸和熊果酸同时测定的反向高效液相色谱法（HPLC）,发现落叶期山杏叶富含三萜酸,为山杏叶综合开发利用提供了基础数据。 相似文献