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1.
Microphysiometry was used to evaluate the effects of terpene trilactone and flavonoid constituents of Ginkgo biloba on human platelet‐activating‐factor receptor (PAFR). Inhibition of the platelet‐activating factor response by terpene trilactones was confirmed using this functional assay. Ginkgolide B (GB) and 10‐O‐benzyl‐GB showed the strongest inhibition (81 and 93%, resp.) of the PAFR response, while the flavonoids rutin, quercetin, and kaempferol showed negligible response inhibition. G. biloba extract mixtures were also tested, and results indicate possible synergistic effects among various components.  相似文献   

2.
The leaves of Ginkgo biloba L. have received much attention, whereas there has been little systematic analysis of the cortex and xylem from roots and branches. A comprehensive evaluation of the 44 compounds in the cortex and xylem would thus be of value to fully understand the potential medicinal properties of roots and branches. An assay of amino acids, terpene lactones, flavones, and phenolic acids was accomplished using ultra high performance liquid chromatography with tandem mass spectrometry. All of the calibration curves showed good linear regression (R2 > 0.9902) within the tested ranges. The intra‐ and interday precision was less than 4.9% and the accuracy was within ±6.8%. The amount of terpene lactones in the cortex was 1.75–2.07‐fold higher than that in the leaves. The amount of glutamine (360 μg/g) in the taproot xylem was 2.64‐fold higher than that in the leaves (136 μg/g). Principal component analysis decreased in the order leaves > taproot cortex > rootlet > laterals cortex > branch cortex > stem cortex > taproot xylem > branch xylem > laterals xylem > stem xylem. The taproot of G. biloba might provide a supplementary source of terpene lactones, especially ginkgolide A and C, and of glutamine.  相似文献   

3.
In this study, an effective method was developed for the isolation and enrichment of Ginkgo biloba extract by continuous chromatography system. The adsorption and desorption ratio of flavonoids as main index, the best macroporous resin was screened out from six resins by static adsorption and desorption tests. At the same time the adsorption and desorption parameters were optimized by dynamic adsorption and desorption tests. Under optimal parameters, five operations consisting of loading, washing, desorbing, regenerating, and balancing were integrated across the continuous chromatography system for the purpose of refining 66 L of crude extract solution. The results were as follows, 198.22 g of Ginkgo biloba extracts was produced, which contained 65.83 g of flavonoids and 15.44 g of lactones. The content of flavonoids and lactones increased from 2.76 and 0.72% in the crude extract to 33.21 and 7.79%, with a recovery yield of 91.26 and 81.21%. Methodology validation showed that the proposed method had high stability and reproducibility. Compared with the traditional macroporous resin method, the proposed method had a short processing time and low solvent consumption. Our studies indicated that the newly developed method is an effective procedure for the isolation and enrichment of Ginkgo biloba extract.  相似文献   

4.
The flavonoids and the terpene lactones are regarded as the two main active components of Ginkgo biloba that affect human health. In the work discussed in this paper, two analytical methods for the characterization of G. biloba authentic materials and commercial products, an LC–UV chromatographic fingerprinting method and a traditional flavonol quantification method, were compared. The traditional method was used to determine the total flavonol content (as glycosides) after acid hydrolysis. The fingerprinting method examined the chromatographic profiles of methanol–water extracts using chemometric methods. The traditional method showed that all the commercial products met the current voluntary standard of 24% flavonols by weight. The chromatographic fingerprinting method revealed significant variations in the commercial products with regard to the relative concentration of individual flavonols.  相似文献   

5.
Abstract

The chemical profile of Bambusa multiplex cv. Fernleaf (B. multiplex) leaves was analysed by UPLC-DAD-Q-TOF-MS. Twelve compounds were identified and C-glycosyl flavonoids, including vitexin, isovitexin, isoorientin and its derivatives, are the main constitutes of the plant. Besides, a HPLC method for isoorientin quantification was developed. The RSD of retention time and peak area were 0.05% and 2.04% for six times analysis of isoorientin with concentration of 20?μg/mL. The recovery of isoorientin in real sample was 99.2%. The general trend of isoorientin content in B. multiplex leaves was that it steady increased from Jan. to May, and then quickly decreased. The maximum was found on May with value of 4.7?mg/g. The lowest level of isoorientin was found during Aug. to Nov. with value of about 1.66?mg/g. In different seasons, isoorientin is always the most dominant flavonoid which was accounted for about 50% of total flavonoids in the sample.  相似文献   

6.
Ginkgo biloba is one of the most popular herbal nutritional supplements, with terpene lactones and flavonoids being the two major active components. An on-line purification high-performance liquid chromatography/mass spectrometry (HPLC/MS) method was successfully developed for the quantitative determination of flavonoids and terpene lactones excreted in human urine after ingesting the herbal supplement. Satisfactory separation was obtained using a C18 capillary column made in-house with sample clean-up and pre-concentration achieved using a C18 pre-column with column switching. High selectivity and limits of detection of 1-18 ng/mL were achieved using a selected ion monitoring (SIM) scan in negative ion mode; the on-line solid-phase extraction (SPE) recovery of the active components in Ginkgo biloba determined in this study was greater than 75%.  相似文献   

7.
Deep eutectic solvents (DESs)-based ultrasonic extraction of terpene trilactones (TTLs) from Ginkgo biloba leaves was efficiently developed. Sixteen DESs were prepared, and DESs composed of choline chloride-urea (ChCl-U) and betaine-ethylene glycol (BE-EG) gave higher TTL extraction yields than the present, most efficient solvent 70% ethanol. The extraction conditions were further optimized, and the optimum conditions were as follows: taking BE-EG containing 40% (w/w) water as the extraction solvent, 1:10 of G. biloba leaves powder-to-solvent ratio, and ultrasonic treatment at 45°C and 100?W for 20?min. A total extraction yield of 1.94?±?0.03?mg/g was obtained under the optimum conditions, which indicated that 99.37% of TTLs could be extracted from the G. biloba leaves powder by a single extraction. Moreover, the polyamide resin was used to recover the TTLs in DES extracting solution, and recovery yield of 95.1% was attained. Therefore, BE-EG containing 40% (w/w) water was a potential alternative solvent for TTLs extraction from G. biloba leaves.  相似文献   

8.
Abstract

GC-EIMS analysis, antifungal- and anti-aflatoxigenic activities of the ethanolic extract of Capsicum chinense and Piper nigrum fruits and their main bioactive compounds were evaluated upon Aspergillus parasiticus. The GC-EIMS analysis showed capsaicin (50.49%) and piperine (95.94%) as the major constituents in C. chinense and P. nigrum, respectively. MIC50 values revealed that capsaicin (39?μg/mL) and piperine (67?μg/mL) were lower than those from fruit extracts of C. chinense (381?μg/mL) and P. nigrum (68?μg/mL). Extracts and bioactive compounds showed anti-aflatoxigenic activity. Maximum aflatoxin inhibition occurred at 150?µg/mL of extracts and compounds. The present study showed satisfactory results concerning the effects of ethanolic extract of C. chinense and P. nigrum fruits upon A. parasiticus, showing the capabilities of inhibiting fungal growth development and altering aflatoxins production.  相似文献   

9.
Neither secondary metabolites of the spring leaves nor the autumn leaves of Eleutherococcus senticosus species cultivated in Poland, or the bioactivity are known. The richest in polyphenols was the autumn leaves (171.1 mg/g DE), while in flavonoids the spring leaves (107.9 mg/g DE). Using LC-ESI-MS/MS, protocatechuic acid has been identified as the most abundant compound in the spring and autumn leaves (200 and 70 μg/g DE, respectively). Amongst flavonoids, naringenin 7-O-glucoside occurred in the largest amount (20 and 10 mg/g DE in the spring and autumn leaves, respectively). The autumn leaves inhibited Hyal the strongest (74.3%), comparing to the spring leaves (33%). A weak inhibition was found towards AChE (0.64 and 5.8% for the autumn and spring leaves, respectively). To our best knowledge, no information was available on the phytochemical composition and activity of the leaves of E. senticosus cultivated in Poland.  相似文献   

10.
A method of ultra high performance liquid chromatography coupled to quadrupole time‐of‐flight mass spectrometry was developed for the simultaneous quantification of 11 sesquiterpene lactones in 11 Jerusalem artichoke leaf samples harvested in a number of areas at different periods. The optimal chromatographic conditions were achieved on a ZORBAX Eclipse Plus C18 column (3.0 × 150 mm, 1.8 μm) with linear gradient elution of methanol and water in 8 min. Quantitative analysis was carried out under selective ion monitoring mode. All of the sesquiterpene lactones showed good linearity (R 2 ≥ 0.9949), repeatability (relative standard deviations < 4.66%), and intra‐ and interday precisions (relative standard deviations < 4.52%) with an accuracy of 95.24–104.84%. The recoveries measured at three concentration levels varied from 95.07 to 104.87% with relative standard deviations less than 4.9%. The limit of detection and limit of quantitation for this method were 0.89–5.05 and 1.12–44.33 ng/mL, respectively. The results showed that the contents of sesquiterpene lactones varied significantly in the Jerusalem artichoke leaf samples from different areas. Among them, the content of sesquiterpene lactones in the sample collected from Dalian, Liaoning province was the highest and the early flowering period was considered to be the optimal harvest time.  相似文献   

11.
Eremanthus species display sesquiterpene lactones with therapeutic potential. We are proposing the development of a new analytical method that has been completely validated to qualify Eremanthus species and its main lactones in raw material using HPLC‐ELSD. For the sample preparation, 10.0 mg of powdered Eremanthus leaves was extracted with a 5 mL MeOH/H2O (9:1 v/v) solution containing scopoletin at 140 µg/mL as the internal standard. For the separation of eight compounds, six of which were lactones, one internal (IS) and one secondary standard were performed utilizing monolithic columns with a nonlinear gradient. The selectivity, stability, precision and matrix effects parameters showed values of RSD of <10%. The six lactones and scopoletin (IS) were recovered with a proportion between 74 and 90% with accuracy represented by error at ?25.41%. The linear dynamic range was obtained between 10.0 and 310.0 µg/mL for all compounds with r2 > 0.9987. The limits of detection and quantitation ranged from 2.00 to 6.79 µg/mL and from 6.00 to 20.40 µg/mL, respectively. Assessing the robustness study, this method can be used in inter‐laboratory studies. Using the HPLC‐ELSD method, six sesquiterpene lactones including 4β,5‐dihydro‐2′,3′‐dihydroxy‐15‐deoxy‐goyazensolide, goyazensolide, 4β,5‐dihydro‐2′,3′‐epoxy‐15‐deoxy‐goyazensolide, centratherin, 4β,5‐dihydro‐15‐deoxy‐goyazensolide and lychnofolide, were detected and quantified from distinct Eremanthus species, which were collected in different regions. Copyright © 2015 John Wiley & Sons, Ltd.  相似文献   

12.
The aim of this study was to identify the presence of tannins, phenols and flavonoids on the hydroalcoholic extract of Caryocar coriaceum leaves (HECCL) and to determine the antioxidant and antibacterial activity of this extract. The extract was tested alone (1024–1 μg/mL) or associated (MIC/8) with several antibiotics in order to identify any antibacterial activity against multiresistant bacterial strains (Escherichia coli, Staphylococcus aureus and Pseudomonas aeruginosa). The existence of tannins, total phenols (901.31 mg/g) and flavonoids (89.68 mg/g) was confirmed in the HECCL. The presence of rutin and quercetin were confirmed by Thin-layer chromatography (TLC). Using the 2,2-diphenyl-1-picrylhydrazyl (DPPH) method, the antioxidant activity of the extract (9 μg/mL) was determined. Moreover, the Minimum Inhibitory Concentration (MIC) value found for HECCL was 1024 μg/mL and the association between HECCL (MIC/8) with benzylpenicillin significantly changed its minimum inhibitory concentration from 2500 to 625 μg/mL against E. coli.  相似文献   

13.
Ethanol extract and fractions obtained from fresh and dry aerial parts of Lippia alba were examined in order to determine their phytochemical composition, antioxidant capacity and antibacterial activities. The ethanol extracts and fractions exhibited an antioxidant effect by the DPPH assay, especially samples of fresh plant. HPLC analysis of the ethyl acetate fractions identified the presence of phenolic acids and flavonoids. The ethanol extract and fractions showed activity against reference and multidrug-resistant strains of Staphylococcus aureus and Enterococcus faecalis (MIC range 2000–250 μg/mL). The hexane and dichloromethane fractions of fresh plant showed better activity against reference strains of Escherichia coli (MIC of 250 and 125 μg/mL, respectively), but all extracts and fractions were less active against multidrug-resistant strains of all the Gram-negative species evaluated. The results showed that the extract and fractions of L alba aerial parts showed antibacterial activity, even against multidrug-resistant Gram-positive bacteria, and antioxidant effect (DPPH assay).  相似文献   

14.
Abstract

Two new compounds, 5-[2-hydroxypropane-1-yl]-2,6-dimethlbenzene-1,3-diol (1) and coniochaetone L (2), together with 19 known compounds (3–21), were isolated from a deep-sea fungus, Penicillium sp. SCSIO 06720. Their structures and absolute configurations were elucidated by detailed NMR, MS spectroscopic analyses, chiral-phase HPLC analysis, and electronic circular dichroism spectra. All the isolated compounds (1–21) were tested for their antibacterial and HIV latency-reversal activities. Among these compounds, compound 16 showed moderate antibacterial activities against Staphylococcus aureus ATCC 29213 and Methicillin-Resistant Staphylococcus Aureus-shh-1 with MIC values of 10.4?±?3.7?μg/mL and 46.9?±?29.7?μg/mL, respectively, which were comparable to that of the positive control ampicillin with MIC values of 0.5?±?0.4?μg/mL and 2.7?±?0.9?μg/mL, respectively.  相似文献   

15.
This study was designed to investigate antioxidant and anticholinesterase potential of Iris germanica var; florentina. Acetylcholinesterase (AChE) and butyrylcholinesterase (BChE) inhibitory potential of plant samples were investigated by Ellman’s assay. Antioxidant activity was performed using DPPH, H2O2 and ABTS free radical scavenging assays. Total phenolics and flavonoids contents were expressed in mg GAE/g dry weight and mg RTE/g, respectively. In AChE inhibition assay, Ig.Fl, Ig.Sp and Ig.Cf fractions exhibited highest activity with IC50 values of < 0.1, 5.64 and 19 μg/mL, respectively. In BChE inhibitory assay, Ig.Fl, Ig.Sp, Ig.Cf and Ig.Cr were most active with IC50 of < 0.1, < 0.1, 31 and 78 μg/mL, respectively. In DPPH assay, Ig.Fl and Ig.Cf exhibited highest inhibition of free radicals, 80.52% (IC50 = 9 μg/mL) and 78.30% (IC50 = 8 μg/mL), respectively. In ABTS assay Ig.Cr, Ig.Cf, Ig.Fl and Ig.Sp exhibited IC50 values of < 0.1, 2, 2 and 3 μg/mL, respectively.  相似文献   

16.
Abstract

Hyptis pectinata is a herb popularly used in Brazil for the treatment of inflammations, pain, bacterial infections and cancer. In the present study, inflorescences (MPIn), leaves (MPL), branches (MPB), root (MPR) extracts and three compounds isolated from MPIn were assayed against breast tumor cell lines. The structures of the three compounds (pectinolide J, hyptolide and pectinolide E) were determined by means of spectroscopic analysis. Pectinolide J was isolated for the first time. The MPIn, MPL and MPR exhibited specific antiproliferative activity on tumor cell lines when compared to normal cell lines with IC50 of 52.01?±?0.64, 45.91?±?0.02?μg/mL and 82.84?±?0.03?μg/mL, respectively. Although the isolated substances did not present good antiproliferative activity, when the three were associated, a greater biological effect was observed, suggesting a synergistic effect. Hyptolide (5.6?±?0.4?μg/mL) showed IC50 sufficiently low to be considered as a drug prototype.  相似文献   

17.
Abstract

A series of novel 1,2,4-triazole derivatives containing a pyrimidine moiety were synthesized and their fungicidal activities were evaluated. The preliminary biological test indicated that some of the target compounds exhibited moderate to good fungicidal activities against the tested plant pathogenic fungi compared with the commercial agent. Among them, compounds 9n and 9o exhibited excellent antifungal activity against Phompsis sp., with the half-maximal effective concentration (EC50) values of 25.4 and 31.6?μg/mL, which were even better than the commercial agent of Pyrimethanil (32.1?μg/mL). Meanwhile, compound 9o showed better fungicidal activities against B. dothidea and B. cinerea with 40.1 and 55.1?μg/mL, respectively, in comparison with that of commercial Pyrimethanil (57.6 and 62.8?μg/mL).  相似文献   

18.
Abstract

A fishing platform was developed using immobilized capillary enzyme reactors in combination with liquid chromatography-mass spectrometry (LC-MS) to fish acetylcholinesterase inhibitor (AChEI) from Mahonia bealei (Fort.) Carr. (M. bealei) extract. Four potential AChEIs (columbamine, jatrorrhizine, berberine, and palmatine) were successfully screened out and identified. Their AChE inhibitory activities were further verified by an in vitro assay with IC50 values of 0.93?±?0.12?μg/mL (columbamine), 3.50?±?0.15?μg/mL (jatrorrhizine), 2.51?±?0.12?μg/mL (berberine), and 1.52?±?0.13?μg/mL (palmatine). A synergy study of these AChEIs was subsequently investigated. In comparison with the IC50 value of M. bealei extract (IC50=0.83?±?0.21?μg/mL), it can be stated that M. bealei extract is much more active than any single AChEI. Thereafter, the determination of these four alkaloids were investigated and AChE inhibitory effect were compared in terms of the extract and corresponding contents of these four alkaloids. The inhibitory effects of extract at each concentration were stronger than four alkaloids mixture. The results demonstrated that not the four AChEI mixture cause the synergistic effect but rather than the concentrations or ratios of these AChEIs play a vital role in their synergy study.  相似文献   

19.
A single-laboratory validation was completed for a method to determine total terpene lactones in Ginkgo biloba products. The method determines terpene lactones on the basis of the main terpene lactones (Bilobalide, Ginkgolide A, Ginkgolide B, Ginkgolide C, and Ginkgolide J) by high-performance liquid chromatography with evaporative light-scattering detection after extraction. Nine matrixes were chosen for study, including crude leaf material, standardized dry powder extract, single- and multiple-entity finished products, and alcohol and glycerin tinctures. The sample purification with prepacked columns allows selective extraction of the terpene lactones with no interferences from any matrix under study. A Youden ruggedness trial testing 7 instrumental and preparation factors with the potential to affect quantitative results showed that 2 factors (volume of the column elution solvent and pH of the diluent) were the most important parameters to control during sample preparation. The method performed well in terms of precision; 4 matrixes tested in triplicate over a 3-day period showed an overall repeatability relative standard deviation (RSD) of about 3%. HorRat values were within the limits for performance acceptability, ranging from 0.5 to 1.0. Analysis of variance testing at a = 0.05 showed no significant differences among the within-or between-group sources of variation, although comparison of within-day, between-day, and total precision showed that most of the RSD came from within-day determinations except those for the Ginkgo dry extract (Gb-SLV-2). Accuracy testing at 4 concentration levels of terpene lactones obtained by spiking a negative control matrix at approximately 300, 750, 1500, and 2250 microg/mL gave recoveries of about 91% for the 300 microg/mL level, about 98% for the 750 microg/mL level, about 99% for the 1500 microg/mL level, and 97% for the 2250 microg/mL level with an overall recovery of 96% and an RSD of 3.2%.  相似文献   

20.
Ginkgo biloba L. has always been a popular area of research due to its various active ingredients and pharmacological effects. Ginkgo biloba is rich in ginkgo flavonoids, ginkgolides, and ginkgolic acid, with anti-inflammation, antioxidation, neuroprotection, anti-platelet agglutination, hypolipidemic effect, anti-cancer, and anti-radiation properties. There are many methods to extract and separate the active components of ginkgo. Among them, supercritical carbon dioxide fluid extraction (SFE-CO2) is known for its green, clean, and environment-friendly properties. In this paper, the pharmacological activities, the active components, and structures of different parts of ginkgo, the extraction methods of its effective ingredients, and the application of the SFE-CO2 method for the extraction and separation of active ingredients in Ginkgo biloba from leaves, seeds, pollen, and roots were reviewed, in order to make best use of ginkgo resources, and provide support and references for the development of SFE-CO2 of active components from Ginkgo biloba.  相似文献   

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