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1.
Species identification of five Dendrobium plants was conducted using phylogenetic analysis and the validity of the method was verified. Some Dendrobium plants (Orchidaceae) have been used as herbal medicines but the difficulty in identifying their botanical origin by traditional methods prevented their full modern utilization. Based on the emerging field of molecular systematics as a powerful classification tool, a phylogenetic analysis was conducted using sequences of two plastid genes, the maturase-coding gene (matK) and the large subunit of ribulose 1,5-bisphosphate carboxylase-coding gene (rbcL), as DNA barcodes for species identification of Dendrobium plants. We investigated five medicinal Dendrobium species, Dendrobium fimbriatum, D. moniliforme, D. nobile, D. pulchellum, and D. tosaense. The phylogenetic trees constructed from matK data successfully distinguished each species from each other. On the other hand, rbcL, as a single-locus barcode, offered less species discriminating power than matK, possibly due to its being present with little variation. When results using matK sequences of D. officinale that was deposited in the DNA database were combined, D. officinale and D. tosaense showed a close genetic relationship, which brought us closer to resolving the question of their taxonomic identity. Identification of the plant source as well as the uniformity of the chemical components is critical for the quality control of herbal medicines and it is important that the processed materials be validated. The methods presented here could be applied to the analysis of processed Dendrobium plants and be a promising tool for the identification of botanical origins of crude drugs.  相似文献   

2.
Three new ent-abietanoids, named xerophilusins XIV–XVI, and four known analogues, as well as four known chemical constituents were isolated from the leaves of Isodon xerophilus. Their structures were elucidated by extensive spectroscopic studies, and comparison with literature data. In addition, the cytotoxic activity of the ent-abietanoids against chronic myelogenous leukemia (K562), stomach adenocarcinoma (MKN45), and hepatocellular carcinoma (HepG2) human cell lines was investigated and no activities were observed.  相似文献   

3.
4.
A new Erythrina alkaloid, 10-hydroxy-11-oxoerysotrine (1), has been isolated from the flowers of Erythrina herbacea together with five known compounds: erytharbine (2), 10,11-dioxoerysotrine (3), erythrartine (4), erysotramidine (5) and erysotrine-N-oxide (6). The structure of the new compound was elucidated on the basis of its spectral data, including 2-D NMR and mass (MS) spectra. The new compound is a rare C-10 oxygenated Erythrina alkaloid. The antioxidant activities of the isolated compounds 16 were evaluated by scavenging with peroxynitrite.  相似文献   

5.
Bioassay-guided fractionation of the MeOH extract of Suaeda glauca yielded four phenolic compounds, methyl 3,5-di-O-caffeoyl quinate (1) and 3,5-di-O-caffeoyl quinic acid (2), isorhamnetin 3-O-beta-D-galactoside (3), and quercetin 3-O-beta-D-galactoside (4). Compounds 1 and 2 were hepatoprotective against tacrine-induced cytotoxicity in human liver-derived Hep G2 cells with the EC(50) values of 72.7+/-6.2 and 117.2+/-10.5 microM, respectively. Silybin as a positive control showed an EC(50) value of 82.4+/-4.1 microM.  相似文献   

6.

Rationale  

±3,4-Methylenedioxymethamphetamine (MDMA, ‘ecstasy’) is a psychoactive drug that has marked effects on the serotonergic system. Serotonergic agonists are known to interact with the circadian pacemaker located in the suprachiasmatic nuclei (SCN).  相似文献   

7.
8.
Twenty-eight samples of mericarps of Perilla frutescens var. frutescens were collected through fieldwork performed in Phongsali and Xieng Khouang provinces in northern Laos. No perilla samples were collected from Savannakhet province in the south although more than 20 sites were investigated. Perilla plants are mostly grown mixed with dry-paddy rice by slash-and-burn cultivation in Laos. The most popular local name for perilla mericarps in the area was “Ma Nga Chan”. Weight of 1,000 grains and hardness of the mericarps were measured, and all mericarps were found to be large (weight of 1,000 grains around 2 g) and soft (limit load weight under 300 g), which were preferred for culinary use in Laos. The composition of the essential oils obtained from the herbaceous plants raised from the mericarps was divided into five types, perillaketone, elemicine plus myristicine, shisofuran, piperitenon, and myristicine, and GC–MS analysis of these Laotian perilla samples showed that they were similar to those of corresponding types of known Japanese perilla strains. One of the shisofuran-type perilla contained large amounts of putative α-naginatene, which is likely to be an intermediate of the biosynthesis of naginataketone. The farmers' indifference to the oil type of the leaf seems to leave Laotian perilla as a good genetic resource for studies of the biosynthesis of oil compounds.  相似文献   

9.
A new C-alkylated flavonoid (5,7-dihydroxy-3′-(4″-acetoxy-3″-methylbutyl)-3,6,4′-trimethoxyflavone (1), along with two known C-alkylated flavonoids (5,7-dihydroxy-3′-(3-hydroxymethylbutyl)-3,6,4′-trimethoxyflavone (2), 5,7,4′-trihydroxy-3′-(3-hyroxymethylbutyl)-3,6-dimethoxyflavone (3) and two new source C-alkylated flavonoids (5,7-dihydroxy-3′-(2-hydroxy-3-methyl-3-butenyl)-3,6,4′-trimethoxyflavone (4), 5,7,4′-trihydroxy-3,6-dimethoxy-3′-isoprenyl-flavone (5) were isolated from the aerial parts of Dodonaea viscosa. The structures of all compounds were established on the basis of 1D and 2D NMR spectroscopy and mass spectrometry. The isolated compounds were evaluated for their inhibitory effect on urease and α-chymotrypsin enzyme. All the compounds (1–5) exhibited mild inhibition against urease but remained recessive in case of α-chymotrypsin.  相似文献   

10.

Purpose  

It has been suggested that drug-metabolizing enzymes might play important roles in the development of anti-tuberculosis drug (ATD)-induced maculopapular eruption (MPE), as in ATD-induced hepatitis. We investigated the associations between the genetic polymorphisms of drug-metabolizing enzymes and ATD-induced MPE.  相似文献   

11.
Objective This study aimed to evaluate the safety for an injection with a mixture of extracts from Herba Artemisiae annuae, Fructus Gardeniae and Flos Lonicerae and to determine the risk factors that may affect its adverse drug reactions. Methods A drug-oriented prospective observational study was performed. Physicians filled in clinical observation forms with detailed information of the patients including general information, drug information, therapeutic effects and adverse drug events. The adverse drug reaction factors were analyzed by both mono-factor and multiple-factor logistic regression methods. Results From April to July 2007, we collected 12,427 observation forms from 46 hospitals in Jiangsu Province of China. Among the 11,707 observation forms we analyzed, 8,074 patients were children younger than 14 years old (69%). Among 51 reported adverse drug events, 45 cases were adverse drug reactions. The total adverse drug reaction incidence of the injection was 0.38%. While most adverse drug reactions were previously known (e.g., rash, pruritus, vomiting and diarrhea), we observed three new ADR symptoms: shiver, phlebitis and anhelation. All the adverse drug reactions were controlled very well through the follow-up therapy, and none of them was life threatening. The mono-factor analysis showed that adverse drug reactions of the injection were significantly correlated with total medication dose (P = 0.0049) and combination medication (P = 0.0143), especially with antimicrobial drugs (P = 0.0079) and macrolides (P = 0.0017). The multiple factor analysis confirmed these results: medication dosage and combination medication had a crucial impact on adverse drug reactions of the injection; the risk was increased by 24.8% (the estimated value of relative risk was 1.248, 95% confidence interval: 1.054–1.479) and 89% (1.890, 1.001–3.566), respectively. Conclusion The total adverse drug reaction incidence of the injection was 0.38% and lower than we expected. Moreover, we observed three new adverse drug reactions, none of which was severe.  相似文献   

12.
Oxidized low-density lipoprotein (oxLDL) plays a key role in the inflammatory processes of atherosclerosis. Jaceosidin isolated from the methanolic extracts of the aerial parts of Artemisia princeps Pampanini cv. Sajabal was tested for antioxidant and anti-inflammatory activities. Jaceosidin inhibited the Cu2+-mediated LDL oxidation with IC50 values of 10.2 μM in the thiobarbituric acid-reactive substances (TBARS) assay as well as the macrophage-mediated LDL oxidation. The antioxidant activities of jaceosidin were exhibited in the conjugated diene production, relative electrophoretic mobility, and apoB-100 fragmentation on copper-mediated LDL oxidation. Jaceosidin also inhibited the generation of reactive oxygen species (ROS) concerning in regulation of NF-κB signaling. And jaceosidin inhibited nuclear factor-kappa B (NF-κB) activity, nitric oxide (NO) production, and suppressed expression of inducible nitric oxide synthase (iNOS) in lipopolysaccharide (LPS)-induced RAW264.7 macrophages.  相似文献   

13.
Several new N,N-dialkyl substituted chalcones (chalconoids or benzylideneacetophenones) have been synthesized via the condensation of corresponding N,N-dialkylbenzaldehyde with various aryl methyl ketones. All the chalcones have been synthesized from readily available and cheap starting materials under environmentally benign conditions in very high yields without work up and column chromatographic purification. Synthesized compounds have been tested for their biological activity against pathogenic microorganisms such as Escherichia coli, Bacillus subtilis, and Mycobacterium smegmatis. Anti-cancer activity of these compounds has also been tested against multiple myeloma (RPMI-8226) and human mammary adenocarcinoma (MCF-7) cell lines. The most hydrophilic molecules 23 and 24 showed very good anti-cancer activity against MCF-7 cell lines at low micro-molar concentrations. All the compounds have also been evaluated for their activity against Beta-secretase 1 enzyme. One of the synthesized compounds showed Beta-secretase 1 enzyme inhibition activity at micro-molar concentration.  相似文献   

14.
The aim of our study is to find functional compounds from natural resources. We focus on plants grown in tropical areas, especially Madagascar and Thailand, because they have unique flora and are expected to contain interesting compounds. We review the functional compounds of the seed kernels of Entada phaseoloides and E. rheedei and their biological activities such as anti-proliferation and melanogenesis inhibitory properties, etc.  相似文献   

15.
Three new acetylated C-glycosylflavones, 3″,6″-di-O-acetylswertiajaponin (1), 4″,6″-di-O-acetylswertiajaponin (2), and 6″-O-acetylswertiajaponin (3), together with six known compounds were isolated from the whole herb of Swertia mileensis. Their structures were elucidated on extensive NMR experiments and mass spectrometry studies. 1H and 13C NMR data exhibited doublet signals at room temperature. Variable temperature 1H NMR experiments were carried out to investigate the presence of rotational isomerism of C-glycosylflavones. All compounds showed potential antioxidant activities against apoptosis of H2O2-induced human embryo liver L02 cells.  相似文献   

16.
A novel cycloartane-type triterpenoid was isolated from the fruits of Nandina domestica (Berberidaceae). The structure was characterized as 24-methylene-3-oxocycloartane 13-carboxylic acid on the basis of NMR spectroscopic data.  相似文献   

17.
After a century of applications of the seminal Michaelis-Menten equation since its advent it is timely to scrutinise its principal parts from an in vivo point of view. Thus, the Michaelis-Menten system was revisited in which enzymatic turnover, i.e. synthesis and elimination was incorporated. To the best of our knowledge, previous studies of the Michaelis-Menten system have been mainly based on the assumption that the total pool of enzyme, free and bound, is constant. However, in fact this may not always be the case, particularly for chronic indications. Chronic (periodic) administration of drugs is often related to induction or inhibition of enzymatic processes and even changes in the free enzymatic load per se. This may account for the fact that translation of in vitro metabolism data have shown to give systematic deviations from experimental in vivo data. Interspecies extrapolations of metabolic data are often challenged by poor predictability due to insufficient power of applied functions and methods. By incorporating enzyme turnover, a more mechanistic expression of substrate, free enzyme and substrate-enzyme complex concentrations is derived. In particular, it is shown that whereas in closed systems there is a threshold for chronic dosing beyond which the substrate concentration keeps rising, in open systems involving enzyme turnover this is no longer the case. However, in the presence of slow enzyme turnover, after an initial period of adjustment which may be quite long, the relation between substrate concentration and dose rate reduces to a linear expression. This new open framework is also applicable to transporter systems.  相似文献   

18.
The food/feed quality of a variety of genetically modified (GM) maize expressing Cry1Ab Bt-toxin was tested over the life-cycle of Daphnia magna, an arthropod commonly used as model organism in ecotoxicological studies. Demographic responses were compared between animals fed GM or unmodified (UM) near isogenic maize, with and without the addition of predator smell. Age-specific data on survival and birth rates were integrated and analysed using life tables and Leslie matrices. Survival, fecundity and population growth rate (PGR) data generally disfavoured transgenic Bt-maize as feed for D. magna compared to animals fed the unmodified (UM) near isogenic line of maize. Decomposition of age-specific effects revealed that the most important contributions to a reduced PGR in the GM-fed group came from both fecundity and survival differences early in life. We conclude that juvenile and young adult stages are the most sensitive experimental units and should be prioritized in future research. These stages are often omitted in toxicological/ecotoxicological studies and in feeding trials.  相似文献   

19.
20.
Boi and its original plant Sinomenium acutum from Japan were compared with Seifuto and its botanical origins from China in terms of their internal transcribed spacer (ITS) sequences and major chemical components. Boi, Seifuto, and their botanical origins overall showed seven variable sites in the ITS sequence and six genotypes. Japanese S. acutum and Boi had one nucleotide variation at position 593 to show two genotypes (J1 and J2) and their heterozygote (J3). Seifuto samples and their botanical origins, S. acutum and S. acutum var. cinereum from China, showed three genotypes (C1, C2, and C3), which did not agree with the botanical classification, indicating that they cannot be distinguished according to their ITS sequences. All Seifuto samples from Henan market showed the same ITS genotype (C1). The Japanese and Chinese genotypes differed in the nucleotide position 424, which can be used to distinguish the country of origin of these materials. In the HPLC analysis of six major components, sinomenine (1), magnoflorine (2), menisperine (3), 6-O-methyllaudanosoline glucoside (4), liriodendrin (5), and menisdaurin (6), all were detected in Boi, whereas five (all except for menisdaurin) were detected in Seifuto. The main component in the rhizome of Seifuto was sinomenine, whereas magnoflorine was the main component in the rhizome and the climbing stem of Boi. The content of sinomenine in Seifuto was almost twice that in Boi. Although the individual content of alkaloids 14 differed between Boi and Seifuto, the total contents of these alkaloids were comparable between them both in the climbing stem and rhizome.  相似文献   

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