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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.
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   

7.
Six phenolic compounds were isolated from the flowers of Trachelospermum asiaticum var. intermedium (Apocynaceae). These structures were determined on the basis of spectral data.  相似文献   

8.
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   

9.
Nonylphenol (NP) and octylphenol (OP), both of which are biodegradation products of alkylphenols, are widely used in industrial applications and in some domestic products. These chemicals are found widely in surface water and aquatic sediments. We have carried out a comparative embryotoxicity analysis of the effects of increasing concentrations of NP (seven concentrations ranging from 0.937 to 18.74 μg/l) and OP (six concentrations ranging from 5 to 160 μg/l) on embryos of the sea urchin Arbacia lixula. The indicators evaluated were larval malformations, developmental arrest and embryonic/larval mortality. The results revealed that low concentrations of these chemicals (NP, OP) generally caused malformations in the skeletal system. High concentrations (18.74 μg NP/l, 160 μg OP/l) were found to inhibit the growth of embryos in the early life stages by preventing mitosis. We conclude that NP and OP present a major risk to the normal development of A. lixula at the low concentrations that have been recorded in the environment. These chemicals are therefore most likely to represent an ecological hazard at the population level given the cumulative effects of other environmental pollutants.  相似文献   

10.
The antifungal activities of ligustilide and butylidene phthalide, which are major oil components comprising the essential oil of Ligusticum chuanxiong, in combination with antifungal drugs were evaluated. Checkerboard microtiter and microdilution tests were used to measure combined effects against Trichophyton species, T. erinacei, T. mentagrophytes, T. rubrum, T. schoenleinii, T. tonsurans and T. soudanense. Susceptibility of these Trichophyton species to L. chuanxiong essential oil differed distinctly. The fractional inhibitory concentrations (FICIs) against Trichophyton species ranged between 0.27 and 0.56 for ketoconazole combined with ligustilde or butylidene phthalide, indicating synergism or additive effects between the antibiotic and essential oil compounds. Testing by itraconazole instead of ketoconazole, similar combination effects were observed with FICIs from 0.31 to 0.63 against the tested strains of T. mentagrophytes, T. rubrum, T. schoenleinii, and T. soudanense. Thus, data reported here showed that Trichophyton susceptibility to ketoconazole and itraconazole could be notably improved by ligustilde and butylidene phthalide.  相似文献   

11.
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   

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.
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   

14.
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   

15.
In this study, two aquatic macrophytes Phragmites australis and Schoenoplectus lacustris and corresponding sediment samples were collected every three months from Lake Sapanca (Turkey) and analysed for their heavy-metal contents (Pb, Cr, Cu, Mn, Ni, Zn and Cd). Accumulation factor ratios of plant parts were calculated for all metals, and the two species were compared in terms of accumulation properties. The highest concentrations were measured in the root systems while relatively low concentrations were found in the rhizome and above-ground parts of the plants. The accumulation ratios of root for P. australis were usually higher than the ratios for S. lacustris. While the accumulation ratios of root were higher in winter than in the other seasons for P. australis, for S. lacustris the highest accumulation ratios were found in the autumn. Both plant species were found to be root accumulators of Pb, Cu, Mn, Ni, Zn and Cd.  相似文献   

16.
Objectives  The aims of this study were to characterize the population frequency of PEPT2 (SLC15A2) polymorphic variants in three Asian ethnic populations, namely Chinese, Malay and Asian Indian, and to investigate the associations of ethnicity (Chinese vs. Asian Indian), PEPT2 haplotype and cephalexin pharmacokinetics in healthy Asian subjects. Methods   PEPT2 polymorphisms were screened from a cohort of 96 Chinese, 96 Malay and 96 Asian Indian subjects. Cephalexin (1000 mg, orally) pharmacokinetics was characterized in an additional 15 Chinese and 15 Asian Indian healthy subjects. These 30 subjects were subsequently genotyped for their PEPT2 polymorphisms. Results  In total, ten common single nucleotide polymorphisms (SNPs) were detected in the three populations, forming two PEPT2 haplotypes. There were significant ethnic differences in PEPT2 haplotype distribution: the frequencies of the *1 and *2 alleles were 0.307 and 0.693 in the Chinese population, 0.495 and 0.505 in the Malay population and 0.729 and 0.271 in Asian Indian population, respectively. The C max of cephalexin was significantly lower in the Chinese (29.80 ± 4.09 μg ml−1) population than in the Asian Indian one (33.29 ± 4.97 μg ml−1; P = 0.045). This difference could be explained by the higher average body weight of the Chinese population. There was no other significant difference in cephalexin pharmacokinetics between either ethnic or PEPT2 genotype groups. Conclusion   PEPT2 polymorphism distributions differ significantly between Chinese, Malay and Asian Indian populations. However, cephalexin pharmacokinetics is not meaningfully different between Chinese and Asian Indians. The association between the PEPT2 haplotype and cephalexin pharmacokinetics could not be confirmed, and future studies under better controlled conditions are needed.  相似文献   

17.
A novel gallate of tannin, (−)-epigallocatechin-(2β→O→7′,4β→8′)-epicatechin-3′-O-gallate (8), together with (−)-epicatechin-3-O-gallate (4), (−)-epigallocatechin (5), (−)-epigallocatechin-3-O-gallate (6), and (+)-gallocatechin-(4α→8′)-epigallocatechin (7), were isolated from the tea plant Camellia sinensis (L.) O. Kuntze var. sinensis (cv., Yabukita). The structure of 8, including stereochemistry, was elucidated by spectroscopic methods and hydrolysis. The compounds, along with commercially available pyrogallol (1), (+)-catechin (2), and (−)-epicatechin (3), were examined for toxicity towards egg-bearing adults of Caenorhabditis elegans. The anthelmintic mebendazole (9) was used as a positive control. Neither 2 nor 3 were toxic but the other compounds were toxic in the descending order 8, 7 6, 9, 4, 5, 1. The LC50 (96 h) values of 8 and 9 were evaluated as 49 and 334 μmol L−1, respectively. These data show that many green tea polyphenols may be potential anthelmintics.  相似文献   

18.
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   

19.
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   

20.
There is increasing concern about the sub-lethal effect of hydrophobic chemicals in the water medium. Even though acetone is a commonly used solvent in toxicity testing, few studies have focussed on its chronic toxicity to Daphnia magna and the available results are often contradictory. In this study, acetone was tested on D. magna in a 21-day exposure experiment and the effects on mortality, fertility and morphology of exposed organisms (F0) and offspring (F1–F2, reared without acetone) were evaluated. No significant reduction of survival was observed with increasing concentrations, and no significant reduction in fecundity in any treatment group in terms of average number of daphnids per mother was observed. Abnormal development of second antennae was observed on F1 from F0 exposed to 79 mg l−1 solvent. The ET50 of acetone on the number of mothers that produced deformed offspring over time was 12.5 days. Our results suggest that the acetone concentration should not exceed 7.9 mg l−1, which is 10 times less than the allowed concentration as determined by OECD chronic assays on D. magna. More attention should be paid to small, water-soluble molecules usually considered of low concern for chronic toxicity because they might affect other metabolic pathways.  相似文献   

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