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1.
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   

2.
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   

3.
4.
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   

5.
Bioassay-guided chromatographic purification of the antitubercular chloroform extract of Pandanus tectorius Soland. var. laevis leaves afforded a new tirucallane-type triterpene, 24,24-dimethyl-5β-tirucall-9(11),25-dien-3-one (1), squalene and a mixture of the phytosterols stigmasterol and β-sitosterol. Microplate Alamar Blue Assay (MABA) showed that 1 inhibited the growth of Mycobacterium tuberculosis H37Rv with a MIC of 64 μg/mL, while squalene and the sterol mixture have MICs of 100 and 128 μg/mL, respectively.  相似文献   

6.
Two abietane diterpenes were isolated from cyanobacteria Microcoleous lacustris, 20-nor-3α-acetoxyabieta-5,7,9,11,13-pentaene and 20-nor-3α-acetoxy-12-hydroxy-abieta-5,7,9,11,13-pentaene. These compounds were assayed against Staphylococcus aureus, Staphylococcus epidermidis, Salmonella typhi, Vibrio cholerae, Bacillus subtilis, Bacillus cereus, Escherichia coli, and Klebsiella pneumoniae. Both compounds showed activity against S. aureus, S. epidermidis, S. typhi, and V. cholerae, but not against the other bacteria.  相似文献   

7.
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   

8.
A new lignan glucoside (1) was isolated from the stems of Callicarpa japonica Thunb. var. luxurians Rehd. (Verbenaceae), along with six known lignan glucosides and three known triterpenoids. The chemical structure of 1 was characterized as (+)-lyoniresinol 3α-O-(6″-3,5-dimethoxy-4-hydroxybenzoyl)-β-d-glucopyranoside on the basis of spectroscopic data. In addition, the radical-scavenging effect of four lignans on the stable free radical 1,1-diphenyl-2-picrylhydrazyl was examined. Among the tested compounds, three compounds, including 1, showed almost the same scavenging activity as that of α-tocopherol.  相似文献   

9.
A new dibenzocyclooctadiene lignan, intermedin A (1), and a new natural bisabolane sesquiterpenoid, intermedin B (2), were isolated from the aerial parts of Schisandra propinqua var. intermedia. Their structures were elucidated on the basis of extensive spectroscopical analysis.  相似文献   

10.
With the goal of developing an accurate plant identification method, molecular analysis based on polymorphisms of the nucleotide sequence of chloroplast DNA (cpDNA) was performed in order to distinguish four Curcuma species: C. longa, C. aromatica, C. zedoaria, and C. xanthorrhiza. Nineteen regions of cpDNA were amplified successfully via polymerase chain reaction (PCR) using total DNA of all Curcuma plants. Using the intergenic spacer between trnS and trnfM (trnSfM), all four Curcuma plant species were correctly identified. In addition, the number of AT repeats in the trnSfM region was predictive of the curcumin content in the rhizome of C. longa.  相似文献   

11.
A new lignan, polystachyol (1), two lignan glycosides, lyoniside (2) and nudiposide (3), and a sterol, ergosta-4,6,8(14),22-tetraen-3-one (4), with stigmasterol, and oleic and linoleic acids, have been isolated from an MeOH extract of the dried bark of Aphanamixis polystachya. The structures of the isolated compounds were elucidated by analysis of 1D and 2D NMR and mass spectroscopic data. The compounds did not have growth inhibitory activity against HeLa cells.  相似文献   

12.
Frequencies of spontaneous mutation from inducible resistance to constitutive resistance were determined for the four clinical isolates of erythromycin-resistant enterococci, including one isolate with ermB gene and three clinical isolates with ermA gene. The rate of ermB mutation was higher than that of ermA mutation by more than 10 fold. Sequence analysis of the regulatory regions of erm genes revealed that mutation type of ermB was just point mutation, by contraries the mutation type of ermA was either deletion or tandem duplication. These results showed distinct characteristics in mutation patterns of ermB and ermA.  相似文献   

13.
By bioassay-guided separation, an already known saponin, Pulsatilla saponin D was isolated from the root of Pulsatilla koreana Nakai as a antitumor component when evaluated by in vivo antitumor activity as well as in vitro cytotoxic activity test. It showed potent inhibition rate of tumor growth (IR, 82%) at the dose of 6.4 mg/kg on the BDF1 mice bearing LLC cells.  相似文献   

14.
From the dried rhizomes of Curcuma comosa cultivating in Thailand, 26 known sesquiterpenes were isolated: zederone, zederone epoxide, furanodienone, isofuranodienone, 1(10)Z,4Z-furanodiene-6-one, glechomanolide, dehydrocurdione, neocurdione, curdione, 7α-hydroxyneocurdione, 7β-hydroxycurdione, germacrone-1(10),4-diepoxide, germacrone, 13-hydroxygermacrone, curzerenone, curcolonol, alismol, alismoxide, zedoarondiol, isozedoarondiol, procurcumenol, isoprocurcumenol, aerugidiol, zedoalactone B, curcumenone, and curcumadione. Their structures were elucidated on the basis of physicochemical evidence. Among them, glechomanolide, curzerenone, curcolonol, alismol, alismoxide, and zedoarondiol showed no significant optical activities, so they may be artifact products during the isolation or drying process.  相似文献   

15.
Digoxin is a drug with a narrow therapeutic index, which is a substrate of the ATP-dependent efflux pump P-glycoprotein. Increased or decreased digoxin plasma concentrations occur in humans due to the inhibition or induction of this drug transporter in organs with excretory function such as small intestine, liver and kidney. It is well known that serum concentrations of digoxin increase considerably in humans if propafenone is given simultaneously. However, it has not been investigated in detail whether propafenone and its metabolites are substrates and/or inhibitors of human P-glycoprotein. The aim of this study, therefore, was to investigate the P-glycoprotein-mediated transport and inhibition properties of propafenone and its major metabolites 5-hydroxypropafenone and N-desalkylpropafenone in Caco-2 cell monolayers. Inhibition of P-glycoprotein-mediated transport by propafenone and its metabolites was determined using digoxin as a P-glycoprotein substrate. No polarised transport was observed for propafenone and N-desalkylpropafenone in Caco-2 cell monolayers. However, 5-hydroxypropafenone translocation was significantly greater from basal-to-apical compared with apical-to-basal (Papp basal–apical vs. Papp apical–basal, 10.21±2.63×10–6 vs. 4.34±1.84×10–6 cm/s; P<0.01). Moreover, propafenone, 5-hydroxypropafenone and N-desalkylpropafenone inhibited P-glycoprotein-mediated digoxin transport with IC50 values of 6.8, 19.9, and 21.3 M, respectively. In summary, whereas propafenone and N-desalkylpropafenone are not substrates of P-glycoprotein, 5-hydroxypropafenone is translocated by human P-glycoprotein across cell monolayers. In addition, propafenone and its two major metabolites 5-hydroxypropafenone and N-desalkylpropafenone are inhibitors of human P-glycoprotein and therefore contribute to the digoxin–propafenone interaction observed in humans.  相似文献   

16.
From the EtOAc-soluble fraction of an MeOH extract of the stems of Tricalysia dubia, two new rearranged ent-kaurane derivatives, named tricalysiolides H and I, were isolated, together with five known rearranged ent-kauranes, i.e. tricalysiolides A–E, stigmast-4-en-6β-ol-3-one, (+)-pinoresinol, scopoletin and syringaldehyde. Their structures were elucidated from spectroscopic evidence, and their cytotoxicity toward KB cells and P-gp inhibitory activity were assayed.  相似文献   

17.
18.
A sesquiterpene lactone, 1-O-acetyl-4R,6S-britannilactone (1) isolated from the flowers of Inula britannica L. var. chinensis (Rupr.) Reg. (Compositae), was found as an iNOS inhibitory constituent for the first time with an IC50 value of 22.1 microM which is more potent than the positive control, L-N6-(1-iminoethyl)lysine (IC50 = 33.7 microM). Structure of compound 1 was identified by 1D and 2D NMR experiments and by comparison with the reference standard.  相似文献   

19.
The dichloromethane extract of the air-dried leaves of Artemisia vulgaris afforded a new sesquiterpene 1, caryophyllene oxide, phytyl fatty acid esters, squalene, stigmasterol and sitosterol. The structure of 1 was elucidated by extensive one- and two-dimensional nuclear magnetic resonance spectroscopy.  相似文献   

20.
Two new aconitine-type C19-diterpenoid alkaloids, hemsleyanines C (1) and D (2), were isolated from the roots of Aconitum hemsleyanium var. circinacum, their structures were determined by the chemical evidence and spectral analyses.  相似文献   

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