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1.
Abstract

The in vitro antifungal activity of extracts obtained from 14 medicinal plants of the mongolian flora were investigated by measuring their minimal inhibitory concentration (MIC) against fungi cause of cutaneous diseases such as Candida species, dermatophytes and Malassezia furfur. Among the species examined, Stellaria dichotoma L., Scutellaria scordifolia L. Aquilegia sibirica Fisch. Et Schrenk. and Hyoscyamus niger L. extracts demonstrated antifungal activity against all studied fungi. In particular, S. scordifolia L. methanol extract, obtained at room temperature, showed the best activity against Candida spp., Malassezia furfur and dermatophytes with GMMIC50 values of 22?µg/mL, 64?µg/mL and 32?µg/mL, respectively. The flavones, luteolin and apigenin, identified in S. scordifolia extracts, and rutin identified in S. dichotoma and Hyoscyamus niger L. extracts, could be responsible of the observed antifungal activity.  相似文献   

2.
3.
Chitosan (CH) is a biopolymer with biocompatible, biodegradable, and bioactive properties. N,N,N‐trimethyl chitosan chloride (TMC) is a quaternized form of CH that is highly cationic and more water soluble than unmodified CH. The physiological activities of CHs with different molecular weights (Mw) and degrees of TMCs quaternization were investigated in U937 and 3T3‐L1 cell lines. 1H‐NMR spectrometry and size exclusion chromatography were used for characterization of the biopolymers. The half inhibition concentration (IC50) of DPPH‐radical‐scavenging activity was below 0.9 mg/m with quaternized CHs. The IC50 values of chitooligosaccharides, low‐ and medium‐molecular‐weight CHs were 8.4, 10.9, and 13.9 mg/ml, respectively. High‐molecular‐weight CHs and TMCs showed apoptotic activity on U937 cells. T41, a TMC of 549 kDa with a 41% degree of quaternization (DQ), yielded 30.7% apoptotic cell death in U937 at 20 µg/ml and effectively repressed cell differentiation and triglyceride accumulation in 3T3‐L1. Depolymerized CHs reduced triglyceride accumulation but also caused cell differentiation. TMCs showed repressor activity to both cell differentiation and triglyceride accumulation. Increasing the molecular weight of CHs and TMCs generally resulted in increased physiological activity. Copyright © 2010 John Wiley & Sons, Ltd.  相似文献   

4.
Twenty nine novel N‐4‐methyl‐1,2,3‐thiadiazole‐5‐carbonyl‐N′‐phenyl ureas were designed and synthesized, and their structures were confirmed by proton nuclear magnetic resonance (1H NMR), infra red spectroscopy (IR) and high‐resolution mass spectroscopy (HRMS). Compounds V‐9 , V‐11 , V‐12 , V‐15 , V‐19 , V‐21 , V‐22 and V‐24 exhibit excellent activity against Culex pipiens pallens. Compounds V‐12 and V‐22 present good insecticidal activity against Plutella xylostella L. Their median lethal concentrations (LC50) are 164.15 and 89.69 mg·L?1, respectively. Compound V‐11 also has potential wide spectrum of fungicide activity. Its median effective concentrations (EC50) detected from 3.82 µg·mL?1 against Physalospora piricola to 31.60 µg·mL?1 against Cercospora arachidicola. Compounds V‐15 and V‐24 show outstanding induction activities as same as positive controls TDL and ningnanmycin, furthermore V‐24 has the highest induction activity of 41.85%±4.43%. To elucidate the structure activity relationship in these compounds, a 3D‐QSAR model has been built. The established model showed a reliable predicting ability with q2 values of 0.643 and r2 values of 0.982.  相似文献   

5.
Abstract

The chemical composition of Tussilago farfara L. essential oil from the Saguenay-Lac-St-Jean region of Quebec, Canada was analyzed by gas chromatography–flame ionisation detector (GC-FID) and gas chromatography–mass spectrometry (GC-MS), and the antibacterial activity of the oil was tested against Escherichia coli and Staphylococcus aureus. Forty-five (45) compounds were identified from the GC profile. The main components were 1-nonene (40.1%), α-phellandrene (26.0%) and ρ-cymene (6.6%). The essential oil demonstrated antibacterial activity against E. coli (MIC50 = 468 µg·mL?1; MIC90 = 6869 µg·mL?1) and S. aureus (MIC50 = 368 µg·mL?1; MIC90 = 773 µg·mL?1). Dodecanoic acid was found to be active against both bacteria having a MIC50 and MIC90 of 16.4 µg·mL?1 and 95 µg·mL?1, respectively for E. coli and a MIC50 and MIC90 of 9.8 µg·mL?1 and 27.3 µg·mL?1, respectively for S. aureus. In addition, 1-decene and (E)-cyclodecene were also found to be active against E. coli.  相似文献   

6.
This study shows the results of application liquid chromatography‐tandem mass spectrometry (LC/MS/MS) for assay of the content of α‐tocopherol and coenzyme Q10 in bee products of animal origin, i.e. royal jelly, beebread and drone homogenate. The biological matrix was removed using extraction with n‐hexane. It was found that drone homogenate is a rich source of coenzyme Q10. It contains only 8 ± 1 µg/g of α‐tocopherol and 20 ± 2 µg/g of coenzyme Q10. The contents of assayed compounds in royal jelly were 16 ± 3 and 8 ± 0.2 µg/g of α‐tocopherol and coenzyme Q10, respectively. Beebread appeared to be the richest of α‐tocopherol. Its level was 80 ± 30 µg/g, while the level of coenzyme Q10 was only 11.5 ± 0.3 µg/g. Copyright © 2016 John Wiley & Sons, Ltd.  相似文献   

7.
A rapid, simple, sensitive, gradient and reproducible, reverse‐phase high‐performance liquid chromatographic method was developed for the quantitative estimation of bioactive alkaloids, lysergol and chanoclavine in the seeds of Ipomoea muricata. The clavine alkaloid, lysergol, is a bioenhancer for the drugs and nutrients. The samples were analyzed by reverse‐phase chromatography on a Waters spherisorb ODS2 column (250 × 4.6 mm, i.d., 10 µm) using binary gradient elution with acetonitrile and 0.01 m phosphate buffer (NaH2PO4) containing 0.1% glacial acetic acid at a flow rate of 0.8 mL/min, a column temperature of 25 °C and UV detection at λ 254 nm. The limits of detection (LOD) and quantitation (LOQ) were 0.035 and 0.106 µg/mL for lysergol and 0.039 and 0.118 µg/mL for chanoclavine, respectively. Standard curves were linear in the range of 2–10 µg/mL (r > 99) for both analytes. Good results were achieved with respect to repeatability (RSD < 2%) and recovery (99.20–102.0). The method was validated for linearity, accuracy repeatability, LOQ and LOD. The method is simple, accurate and precise, and may be recommended for routine quality control analysis of I. muricata seed extracts containing these two clavine alkaloids (1, 2) as bioactive principles of the herb. Copyright © 2011 John Wiley & Sons, Ltd.  相似文献   

8.
Abstract

The present study evaluates the chemical composition of Zinnia elegans and Gazania rigens based on their metabolomic profiles using liquid chromatography coupled with high-resolution mass spectrometry (LC‐HR-MS), alongside with the anti-infective activities of their ethanol extracts, as well as, different fractions. A significant difference was observed between the LC-MS profiles of the two plants such as, coumarins, sesquiterpene lactones and phenylethanoids which were characteristic for Z. elegans, while amides and phenolic acid derivatives were characteristic for G. rigens. These results highlight the chemical potential of Z. elegans and G. rigens. Furthermore, the ethyl acetate fraction of Z. elegans showed a significant antimalarial activity with IC50 values of 21.03 and 13.72?µg/mL against Plasmodium falciparum D6 and P. falciparum W2, respectively.  相似文献   

9.
Three tin(IV) complexes of 2‐benzoylpyridine N(4)‐phenylthiosemicarbazone (H2Bz4Ph) were prepared: [Sn(L)Cl3] (1), [BuSn(L)Cl2] (2) and [(Bu)2Sn(L)Cl] (3), in which L stands for the anionic ligand formed upon complexation with deprotonation and release of HCl. The complexes were characterized by a number of spectroscopic techniques. The crystal structures of H2Bz4Ph and complex 3 were determined. The antifungal activity of the ligand and its tin(IV) complexes was tested against Candida albicans. The thiosemicarbazone proved to be more active than the tin(IV) complexes. Copyright © 2003 John Wiley & Sons, Ltd.  相似文献   

10.
Macroinitiator‐amino terminated poly(ethylene glycol) (PEG) (NH2‐PEO‐NH2) was prepared by converting both terminal hydroxyl groups of PEG to more reactive primary amino groups. The synthetic route involved reactions of chloridize, phthalimide and finally hydrazinolysis. Furthermore, poly(γ‐benzyl‐L ‐glutamate)‐poly(ethylene oxide)‐poly(γ‐benzyl‐L ‐glutamate) (PBLG‐PEO‐PBLG) triblock copolymer was synthesized by polymerization of γ‐benzyl‐L ‐glutamate N‐carboxyanhydride (Bz‐L‐GluNCA) using NH2‐PEO‐NH2 as macroinitiator. The resultant NH2‐PEO‐NH2 and triblock copolymer were characterized by FT‐IR, 1H‐NMR and gel permeation chromatography (GPC) techniques. The results demonstrated that the degree of amination of the NH2‐PEO‐NH2 could be up to 1.95. The molecular weight of the PBLG‐PEO‐PBLG triblock copolymer could be adjusted easily by controlling the molar ratio of Bz‐L ‐Glu NCA to the macroinitiator NH2‐PEO‐NH2. Copyright © 2004 John Wiley & Sons, Ltd.  相似文献   

11.
A fast liquid chromatography method with diode‐array detection (DAD) and time‐of‐flight mass spectrometry (TOF‐MS) has been developed for analysis of constituents in Flos Lonicerae Japonicae (FLJ), a traditional Chinese medicine derived from the flower bud of Lonicera japonica. The chromatographic analytical time decreased to 25 min without sacrificing resolution using a column packed with 1.8‐µm porous particles (4.6 × 50 mm), three times faster than the performance of conventional 5.0‐µm columns (4.6 × 150 mm). Four major groups of compounds previously isolated from FLJ were structurally characterized by DAD‐TOF‐MS: iridoid glycosides showed maximum UV absorption at 240 nm; phenolic acids at 217, 242, and 326 nm; flavonoids at 255 and 355 nm; while saponins had no absorption. In electrospray ionization (ESI)‐TOF‐MS experiments, elimination of a glucose unit (162 Da), and successive losses of H2O, CH3OH and CO, were generally observed in iridoid glycosides; saponins were characterized by a series of identical aglycone ions; phenolic acids typically generated a base peak at [M–H–caffeoyl]? by loss of a caffeic acid unit (162 Da) and several marked quinic acid moiety ions; cleavage of the glycosidic bond (loss of 162 or 308 Da), subsequent losses of H2O, CO, RDA and C‐ring fragmentation were the most possible fragmentation pathways for flavonoids. By accurate mass measurements within 4 ppm error for each molecular ion and subsequent fragment ions, as well as the ‘full mass spectral’ information of TOF‐MS, a total of 41 compounds including 13 iridoid glycosides, 11 phenolic acids, 7 saponins, and 10 flavonoids were identified in a methanolic extract of FLJ. Copyright © 2009 John Wiley & Sons, Ltd.  相似文献   

12.
Two types of three‐arm and four‐arm, star‐shaped poly(D,L ‐lactic acid‐alt‐glycolic acid)‐b‐poly(L ‐lactic acid) (D,L ‐PLGA50‐b‐PLLA) were successfully synthesized via the sequential ring‐opening polymerization of D,L ‐3‐methylglycolide (MG) and L ‐lactide (L ‐LA) with a multifunctional initiator, such as trimethylolpropane and pentaerythritol, and stannous octoate (SnOct2) as a catalyst. Star‐shaped, hydroxy‐terminated poly(D,L ‐lactic acid‐alt‐glycolic acid) (D,L ‐PLGA50) obtained from the polymerization of MG was used as a macroinitiator to initiate the block polymerization of L ‐LA with the SnOct2 catalyst in bulk at 130 °C. For the polymerization of L ‐LA with the three‐arm, star‐shaped D,L ‐PLGA50 macroinitiator (number‐average molecular weight = 6800) and the SnOct2 catalyst, the molecular weight of the resulting D,L ‐PLGA50‐b‐PLLA polymer linearly increased from 12,600 to 27,400 with the increasing molar ratio (1:1 to 3:1) of L ‐LA to MG, and the molecular weight distribution was rather narrow (weight‐average molecular weight/number‐average molecular weight = 1.09–1.15). The 1H NMR spectrum of the D,L ‐PLGA50‐b‐PLLA block copolymer showed that the molecular weight and unit composition of the block copolymer were controlled by the molar ratio of L ‐LA to the macroinitiator. The 13C NMR spectrum of the block copolymer clearly showed its diblock structures, that is, D,L ‐PLGA50 as the first block and poly(L ‐lactic acid) as the second block. © 2001 John Wiley & Sons, Inc. J Polym Sci Part A: Polym Chem 40: 409–415, 2002  相似文献   

13.
A series of novel 1‐(3‐chloropyridin‐2‐yl)‐N‐substituted‐5‐(trifluoromethyl)‐pyrazole carboxamide derivatives TC1 , TC2 , TC3 , TC4 , TC5 , TC6 , TC7 , TC8 , TC9 , TC10 , TC11 were synthesized and characterized by IR, 1H NMR, 13C NMR, MS, and elemental analysis. All the target compounds were tested in vitro for their antibacterial activities and antifungal activities. The preliminary bioassays indicated that compound TC6 exhibited excellent activity against Xanthomonas oryzae (94.9% and 84.9%) at different concentrations (200 µg/mL and 100 µg/mL), which was higher than that of Bismerthiazol (94.6% and 64.0%), respectively. At the same time, most of the compounds exhibited moderate antifungal activities against four kinds of phytopathogenic fungi  相似文献   

14.
Overcoming epidermal growth factor receptor resistance is a critical problem that needs to be solved in clinical practice. Drugs that downregulate the fatty acid synthase‐epidermal growth factor receptor will become novel treatments for non‐small cell lung cancer. Solanum nigrum, extracted with water at 4°C, shows strong cytotoxic activity and inhibits tumor growth in Lewis tumor bearing‐mice in a dose‐dependent manner. A novel active compound in S. nigrum, solaoiacid, was successfully separated and purified from S. nigrum by preparative high‐performance liquid chromatography with mass spectrometry and ultra high performance liquid chromatography with time‐of‐flight tandem mass spectrometry. The IC50 of solaoiacid on lung cancer cells was 2.3 µmol/L, which was significantly lower than that of the known steroidal glycoalkaloid. Label‐free proteomics and STRING Network analysis were used to identify significantly deregulated proteins in lung cancer cells that were treated with the fresh ripe fruit extracts of S. nigrum. S. nigrum regulates multiple signal pathways, including the epidermal growth factor receptor pathway. S. nigrum downregulated 24 main proteins with direct roles in fatty acid biosynthesis. Both S. nigrum and solaoiacid showed strong downregulation of the fatty acid synthase‐epidermal growth factor receptor and anti‐non‐small cell lung cancer effects, and thus will become a novel drug for the treatment of non‐small cell lung cancer.  相似文献   

15.
The study was focused on the structure–activity relationship of some newly synthesized hexacoordinated dimethyltin(IV) complexes of fluorinated β‐diketone/β‐diketones and sterically congested heterocyclic β‐diketones. These complexes were screened for their antibacterial activity against a Gram‐negative bacterium (Pseudomonas aeruginosa) and Gram‐positive bacteria (Streptomyces griseus, Staphylococcus aureus, Bacillus subtilis) and the results were compared with those of a standard antibacterial drug. Some of the complexes were also screened for their antifungal activity against various fungi (Aspergillus niger, A. flavus, Trichoderma viride, Fusarium oxysporum) and were found to be active. These new hexacoordinated complexes of dimethyltin(IV) were generated by reactions of dimethyltin(IV) dichloride and sodium salts of fluorinated β‐diketone/β‐diketones and sterically congested heterocyclic β‐diketones in 1:1:1 molar ratio in refluxing dry benzene. Plausible structures of these complexes were suggested with the aid of physicochemical and spectroscopic studies. 119Sn NMR spectral data revealed the presence of a hexacoordinated tin centre in these dimethyltin(IV) complexes. Copyright © 2015 John Wiley & Sons, Ltd.  相似文献   

16.
A series of novel 2‐substituted methlthio‐5‐(4‐amino‐2‐methylpyrimidin‐5‐yl‐)‐1,3,4‐thiadiazole derivatives were synthesized, characterized and evaluated for antiviral activities against tobacco mosaic virus (TMV). The preliminary biological results indicated that most compounds exhibit excellent antiviral activity against TMV in vivo. Among these compounds, compounds 9c , 9i , and 9p displayed the similar curative effect against TMV (EC50 = 287.05–322.47 µg/mL) to that of the commercial agent Ningnanmycin (EC50 = 301.83 µg/mL). In particular, compound 9d demonstrated the best curative effect against TMV (EC50 = 266.21 µg/mL), which was better than that of commercial Ningnanmycin.  相似文献   

17.
Araucaria angustifolia seeds are characterised by a relatively high content of starch and protein. This study aimed to verify the presence of α-amylase inhibitors in the seeds and to characterise a trypsin inhibitor found in the embryo tissues. Inhibitor purification was carried out by the saline extraction of proteins, acetone precipitation and affinity chromatography. Two protein bands of molecular weight estimated by SDS-PAGE at about 35 kDa were further examined by high-performance liquid chromatography coupled to a mass spectrometer and were shown to be 36.955 Da (AaTI-1) and 35.450 Da (AaTI-2). The sequence of the N-terminal region shows that AaTI-1 and AaTI-2 are structurally similar to plant inhibitors of the serpin family. A mixture of AaTI-1 and AaTI-2, identified as AaTI, shows selectivity for the inhibition of trypsin (Kiapp 85 nM) and plasmin (Kiapp 7.0 μM), but it does not interfere with the chymotrypsin, human plasma kallikrein, porcine kallikrein or other coagulation enzymes activity.  相似文献   

18.
Based on the structure of natural product 2‐aryl‐4,5‐dihydrothiazole‐4‐carboxylic acid, a series of novel (R)‐2‐aryl‐4,5‐dihydrothiazole‐4‐carboxylic acid derivatives were designed and synthesized. Their structures were characterized by 1H NMR, 13C NMR and HRMS. The single crystal structure of compound 9b was determined by X‐ray diffraction analysis. The antifungal activities were evaluated for the first time. The bioassay results indicated that most compounds exhibited moderate to good antifungal activities. The antifungal activities of compound 13a (against Cercospora arachidicola Hori), 13d (against Alternaria solani), and 16e (against Cercospora arachidicola Hori) were 61.9%, 67.3% and 61.9%, respectively, which are higher than those of the commercial fungicides chlorothalonil and carbendazim. Moreover, compound 13d exhibited excellent antifungal activities against 7 kinds of the fungi tested (66.7%, 77.3%, 63.0%, 87.9%, 70.0%, 70.0% and 80.0% at 50 µg?mL). Therefore, 13d can be used as a new lead structure for the development of antifungal agents.  相似文献   

19.
Factors affecting the syntheses of high‐molecular‐weight poly(2,5‐dialkyl‐1,4‐phenylene vinylene) by the acyclic diene metathesis polymerization of 2,5‐dialkyl‐1,4‐divinylbenzenes [alkyl = n‐octyl ( 2 ) and 2‐ethylhexyl ( 3 )] with a molybdenum or ruthenium catalyst were explored. The polymerizations of 2 by Mo(N‐2,6‐Me2C6H3) (CHMe2 Ph)[OCMe(CF3)2]2 at 25 °C was completed with both a high initial monomer concentration and reduced pressure, affording poly(p‐phenylene vinylene)s with low polydispersity index values (number‐average molecular weight = 3.3–3.65 × 103 by gel permeation chromatography vs polystyrene standards, weight‐average molecular weight/number‐average molecular weight = 1.1–1.2), but the polymerization of 3 was not completed under the same conditions. The synthesis of structurally regular (all‐trans), defect‐free, high‐molecular‐weight 2‐ethylhexyl substituted poly(p‐phenylene vinylene)s [poly 3 ; degree of monomer repeating unit (DPn) = ca. 16–70 by 1H NMR] with unimodal molecular weight distributions (number‐average molecular weight = 8.30–36.3 × 103 by gel permeation chromatography, weight‐average molecular weight/number‐average molecular weight = 1.6–2.1) and with defined polymer chain ends (as a vinyl group, ? CH?CH2) was achieved when Ru(CHPh)(Cl)2(IMesH2)(PCy3) or Ru(CH‐2‐OiPr‐C6H4)(Cl)2(IMesH2) [IMesH2 = 1,3‐bis(2,4,6‐trimethylphenyl)‐2‐imidazolidinylidene] was employed as a catalyst at 50 °C. © 2005 Wiley Periodicals, Inc. J Polym Sci Part A: Polym Chem 43: 6166–6177, 2005  相似文献   

20.
The molecular weight and the proposed structure of the Angelica sinensis polysaccharide‐iron complex (APIC) were studied. Fourier transform infrared spectroscopy, X‐ray powder diffraction, differential scanning calorimetry, transmission electron microscopy, electron paramagnetic resonance, thermogravimetric analysis, atomic force microscopy, and gel filtration chromatography were used to characterize APIC, which is a macromolecule complex composed of Angelica sinensis polysaccharide (ASP) and iron. The structure of APIC was proposed to be a polynuclear ferrihydrite core chelated firmly by an encircling framework of ASP chains, forming a core molecule, which is surrounded by a removable outer protective sheath of colloidal ASP. And the molecular formula of APIC was proposed to be {[(Fe2O3·2.2H2O)1043(ASP)32](ASP)12}, with MW=270000 Da.  相似文献   

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