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1.
It has been found by ribosomal DNA analysis that the endophytic filamentous fungi isolated from the tea plant Camellia sinensis (Theaceae) are composed of six groups; one Fusarium sp., one Penicillium sp., two Schizophyllum sp., and two Diaporthe sp..  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.
Maturity index values reflect life history characteristics often inferred by morphology. We tested the hypothesis that Acrobeloides and Aphelenchus are sensitive to chemical pollutants, opposite of what their colonizer-persister (CP) value of 2 suggests. Acrobeloides and Aphelenchus were reared at 19°C and provided diets of Escherichia coli and Rhizoctonia solani, respectively. LC50 values for Aphelenchus exposed to copper or benzo(a)pyrene (BaP) are greater than Acrobeloides. Copper impedes growth of Acrobeloides at 10 μg/g, and results in 100% mortality at 20 μg/g. In contrast, Aphelenchus is more resilient, with no visible impact at 20 μg/g. Acrobeloides and Aphelenchus were sensitive to much lower concentrations of BaP than copper, i.e., 0.5 μg/g inhibited development of Acrobeloides and 2 μg/g for Aphelenchus. Egg size and hatch were unaffected at 15 μg/g copper. In contrast, 0.5 μg/g BaP reduced both egg size and hatch for Aphelenchus but not Acrobeloides. Survival of Acrobeloides and reproduction of Aphelenchus responded differently to copper and BaP, implying the relationship between this classification and their sensitivity to short-term effects may be less straightforward than presumed. Refinement of index values based on empirical evidence can be used to improve sensitivity and interpretation of nematode community indices for environmental monitoring.  相似文献   

4.
Phytochemical investigation of the 50% ethanol eluate fraction of macroporous resin for the flower of Datura metel L. led to the isolation of a new compound named yangjinhualine A (1) and five known megastigmane sesquiterpenes through repeated silica gel and ODS column chromatography and semipreparative HPLC. The structures of these compounds were determined by spectroscopic methods, including 2D-NMR, ESI-MS, and HR-ESI-MS spectrometry as well as by comparison with published data. Five known megastigmane sesquiterpenes were also isolated from D. metel L. for the first time.  相似文献   

5.
A new acylphloroglucinol glycoside was isolated from the leaves of Solidago altissima L. The chemical structure of the glycoside, which has a phloroglucinol moiety with a butyryl side chain, was elucidated based on the analysis of spectroscopic data.  相似文献   

6.
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   

7.
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   

8.
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   

9.
10.
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   

11.
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   

12.
13.
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   

14.
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   

15.
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   

16.
We isolated seven terpenes and five phenolic constituents from the aerial parts of Lactuca indica L. using column chromatographic separation of its MeOH extract. Their structures were determined by spectroscopic methods to be trans-phytol (1), 3beta-hydroxyglutin-5-ene (2), 5,6-epoxy-3-hydroxy-7-megastigmen-9-one (3), 11beta-13-dihydrolactucin (4), 2-phenylethyl beta-D-glucopyranoside (5), cichorioside B (6), 1-hydroxylinaloyl-6-O-beta-D-glucopyranoside (7), (6S,9S)-roseoside (8), benzyl-beta-D-glucopyranoside (9), 2-(3'-O-beta-D-glucopyranosyl-4'-hydroxyphenyl)-ethanol (10), 3-(beta-D-glucopyranosyloxymethyl)-2-(4-hydroxy-3-methoxyphenyl)-5-(3-hydroxypropyl)-7-methoxy-dihydrobenzofuran (11), and (+)-taraxafolin-B (12). Compounds 1-3, 5, and 7-12 were isolated for the first time from this plant source. The isolated compounds were tested for cytotoxicity against four human tumor cell lines in vitro using a Sulforhodamin B bioassay.  相似文献   

17.
A new coumarinolignan glucoside named yinxiancaoside C, along with five known benzofuran lignans, have been isolated from the whole plant of Chloranthus japonicus Sieb. The structures of compounds 1–6 were elucidated by chemical and spectroscopic methods including 1D-NMR, 2D-NMR, ESI-MS and HR-ESI-MS. Five known benzofuran lignans were firstly discovered in the Chloranthaceae. In addition, the cytotoxic activity of the isolated compounds against human hepatoma (Hepg-2), ovarian carcinoma (OV420), and breast cancer (MCF-7) cells was investigated by MTT method.  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.
Seedling development, accumulation and distribution of lead (Pb) in Iris lactea var. chinensis (Fisch.) Koidz. and I. tectorum Maxim. were studied using plants grown in sand culture and exposed to 0–10 mmol l−1 concentrations of Pb supplied as Pb(NO3)2 for 28 days. A significant reduction in dry weight (dw) of shoots and roots of I. lactea var. chinensis was observed at 6 and 10 mmol l−1, respectively, and a significant reduction in dw of shoots and roots of I. tectorum was observed at 6 mmol l−1. Concentration of Pb in the shoots and roots of I. lacteal var. chinensis exposed to 4 mmol l−1 Pb reached 1,109 μg g−1 and 2,408 μg g−1 dw, respectively. The index of tolerance (IT) of I. lactea var. chinensis among 0–8 mmol l−1 Pb treatments were not significantly different, while those of I. tectorum at 6 mmol l−1 Pb were significantly decreased. The results indicated that I. lactea var. chinensis was more tolerant to Pb than I. tectorum. Sub-cellular localization of Pb in root cells was evaluated using transmission electron microscopy (TEM) and Pb deposits were found along the plasma membrane of some root tip cells of I. lactea var. chinensis treated at 10 mmol l−1 Pb. Deposits of Pd were also observed along the surface, in the root tip cell wall and in the cytoplasm of a few malformed cells of I. tectorum exposed at 10 mmol l−1 Pb treatment. One possible mechanism to explain these observations may be that most cells can maintain normal activities in the plant by sacrificing a small number of cells that accumulate a large amount Pb and show toxicity. Future studies should be designed to test this hypothesis.  相似文献   

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