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1.
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   

2.
Abstract

In Brazilian folk medicine, Protium heptaphyllum is used to treat inflammatory conditions and to hasten wound repair. This paper aims to investigate the chemical composition and the in vitro antibacterial effects of the essential oils (EOs) obtained from P. heptaphyllum leaves and ripe and unripe fruits against a representative panel of oral pathogens. The GC-FID and GC-MS analysis revealed that the major components determined in P. heptaphyllum essential oils were myrcene (59.0%), β-elemene (17.2%), limonene (12.9%), spathulenol (12.6%), α-cubebene (11.6%), germacrene D (10.6%), trans-nerolidol (9.8%), and α-cadinol (8.8%). The essential oils of the ripe and unripe fruits showed the strongest antibacterial activity against the anaerobic bacteria Prevotella nigrescens (MIC?=?50?µg/mL). The leaf essential oil displayed very promising activity against Streptococcus mutans (MIC?=?50?µg/mL) and Streptococcus mitis (MIC?=?62.5?µg/mL). The antibacterial activity of EOs against oral pathogens is also described for the first time.

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3.
Abstract

The volatile constituents of the leaves and flowers of Brachychiton rupestris and Brachychiton discolor (Malvaceae) were characterized by GC-FID and GC-MS. A total of 92 compounds were identified. The major component of B. rupestris leaves was α-farnesene (34.57%) while in the flowers it was n-heptacosane (29.5%). (8Z, 11Z, 14Z)-heptadecatrienal (21.2%) in the leaves and palmitic acid (83.49%) in the flowers represent the abundant ingredients of B. discolor. Unsupervised pattern recognition techniques of multivariate data analysis exemplified by hierarchical cluster analysis (HCA) and principle component analysis (PCA) relying upon chromatographic results effectively discriminate the two related species. Also, both investigated species were assessed for their cytotoxic and antimicrobial efficacy. Results revealed that B. discolor flowers showed the highest cytotoxicity against human lung carcinoma (A-549) cell lines with IC50 equals 7.98?μg/mL, whereas B. discolor leaves exhibited the highest antimicrobial potency against all tested microorganisms namely Streptococcus pneumonia, Bacillus subtilis, Escherichia coli as well as Aspergillus fumigatus and Geotrichum candidum (MICs between 0.98 and 15.63?µg/mL) except for Salmonella typhi.  相似文献   

4.
Abstract

In searching for drugs from natural product scaffolds has gained interest among researchers. In this study, a series of twelve halogenated thiourea (ATX 1-12) via chemical modification of aspirin (a natural product derivative) and evaluated for cytotoxic activity against nasopharyngeal carcinoma (NPC) cell lines, HK-1 via MTS-based colorimetric assay. The cytotoxicity studies demonstrated that halogens at meta position of ATX showed promising activity against HK-1 cells (IC50 value ≤15?µM) in comparison to cisplatin, a positive cytotoxic drug (IC50 value =8.9?±?1.9?µM). ATX 11, bearing iodine at meta position, showed robust cytotoxicity against HK-1 cells with an IC50 value of 4.7?±?0.7?µM. Molecular docking interactions between ATX 11 and cyclooxygenase-2 demonstrated a robust binding affinity value of ?8.1?kcal/mol as compared to aspirin’s binding affinity value of ?6.4?kcal/mol. The findings represent a promising lead molecule from natural product with excellent cytotoxic activity against NPC cell lines.  相似文献   

5.
Abstract

Twenty-four compounds were isolated from the roots of Polygonatum cyrtonema Hua, including a new octopamine dimer, named trans-bis(N-feruloyl)octopamine (1). The structure was established on the basis of spectroscopic and chemical methods. All the extracts and compounds were evaluated for cytotoxic and antioxidant activities by using MTT and chemiluminescence assay. The extracts showed activity against MCF-7 and HepG-2 cell lines from IC50 0.30 to 1.01 mg mL?1. Compound 3 exhibited activity against HepG-2 cell lines with IC50 8.99?μM. Compound 7 exhibited activity against Hela cell lines with IC50 2.53?μM and BGC-823 cell lines with IC50 7.77?μM. Moreover, compound 7 showed antioxidant with IC50 12?µM compared to the positive control with IC50 77?µM. Compound 16 exhibited activity against HepG-2 cell lines with IC50 1.05?μM and MCF-7 cell lines with IC50 1.89?μM. These results indicated that this plant might be potential in natural medicine and healthy food.  相似文献   

6.
Herein, we report the synthesis of fluorescent 1,4-dihydropyridine-linked bis-triazoles (2a2n) through Hantzsch synthesis by the condensation of o/m-chloro-substituted benzaldehyde, ethyl 3-oxo-4(prop-2-yn-1-yloxy)butanoate, and ammonium acetate in the presence of Ba(NO3)2 as a catalyst followed by the click reaction of resultant Hantzsch product (1) with various aromatic as well as aliphatic azides. All the synthesized compounds were well characterized by 1H-NMR, 13C-NMR, FTIR, and HRMS spectral techniques. Antibreast cancer evaluation of all the synthesized derivatives revealed that the compounds 2f (IC50?=?7?±?0.02?µM) and 2g (IC50?=?5?±?0.03?µM) showed better anticancer activity (lower IC50) than the standard drug tamoxifen (IC50?=?11.2?±?0.01?µM) against breast carcinoma (MDA-MB-231) cell line. The synthesized compounds were also screened against normal human embryonic kidney (HEK-293) cell line and found to be nontoxic. The fluorescent nature and cytotoxicity assay of these newly synthesized hybrids recommend their utility in tumor cell imaging.  相似文献   

7.
《Analytical letters》2012,45(2):290-307
Abstract

Distinguishing chemicals and improvement on analytical methods has a direct impact on modern chemical analysis. In this work, the dissociative ionization of xylene isomers was investigated using a femtosecond laser mass spectrometry (FLMS) method with a custom-built linear time-of-flight (TOF) instrument. Laser beams at 800?nm and 400?nm were used and intensity-dependent analysis of the obtained mass spectra was performed using principal component analysis (PCA) to distinguish the xylene isomers, which give identical mass spectra in appearance that cannot be distinguished using normal mass spectrometry methods. The results show that there is a statistically highly significant difference between the xylene isomers for two principal components (1 ? α?>?99.99%) and minimal information loss (<5%) took place during the PCA procedure. Also, the use of the k-medoid clustering method showed that the isomers may be distinguished in real-time for a wide range of ionization laser pulse powers with approximately 99% accuracy. The results suggest that real-time isomer analysis by the FLMS method is suitable for mass spectral identification applications. The FLMS method has been shown to be an important alternative to other mass spectrometric methods that use different ionization mechanisms.  相似文献   

8.
Abstract

Two new ceanothane triterpenes, 3,7-O,O-dibenzoyl ceanothic acid methylester (1) and 3-O-acetyl-7-O-benzoyl ceanothic acid methylester (2), along with nine known compounds (311), were isolated from the roots of Colubrina asiatica. The isolated compounds were identified by spectroscopic evidence. Compounds 1 and 2 showed antimalarial activity against Plasmodium falciparum with IC50 values of 4.67 and 3.07?µg/mL, respectively. Compound 2 also showed antimycobacterial activity against Mycobacterium tuberculosis (MIC 6.25?µg/mL). In addition, compounds 1, 2, 10 and 11 showed cytotoxicity against three cancer cell lines (KB, NCI-H187 and MCF-7) with IC50 values ranging from 8.32 to 46.72?µg/mL.  相似文献   

9.
Two Schiff-base copper(II) complexes, bis(N-n-butyl-5-chlorosalicylaldiminato) copper(II) (1) and bis(N-n-butyl-4-methoxysalicylaldiminato) copper(II) (2), were synthesized and their solid-state structures were determined by X-ray crystallography. Complex 1 displays a distorted square-planar geometry, while 2 possesses square-planar geometry. Copper(II) complexes 1 and 2 showed strong inhibitory activity against jack bean urease (IC50?=?2.7, 3.5?µmol?L?1), compared with acetohydroxamic acid (IC50?=?63.00?µmol?L?1). A molecular modeling study was carried out via the DOCK program to gain understanding of the potent inhibitory activity of these copper species against jack bean urease.  相似文献   

10.
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   

11.
The effects of Cr(III) and Cr(VI) species (Cr2O72?, CrO42? and Cr3+) on the growth of Escherichia coli (E. coli) have been investigated in detail by microcalorimetry at 37 °C. Parameters including the growth rate constant (k), inhibitory ratio (I), half‐inhibitory concentration (IC50), total heat output (Qtotal), time of the maximum heat production (tlog) in the log phase have been obtained. The results showed that Cr(VI) and Cr(III) had the inhibition effect on the growth of E. coli in aquatic environment; however, the inhibitory ratio of Cr(III) to E. coli was smaller than that of Cr(VI). The k values of E. coli in the presence of Cr(VI) and at high concentrations of Cr(III) were decreased with increasing the concentrations of these chromium species. Among the three chromium species investigated, Cr2O72? was found to be the most poisonous species against E. coli with an IC50 value of 35.52 µg·mL?1. CrO42? exhibited moderate toxicity on E. coli with an IC50 of 50.24 µg·mL?1, and Cr3+ had the lowest toxicity with an IC50 of 84.30 µg·mL?1. Microcalorimetry can provide a convenient, sensitive and reliable method to study the effect of various metal species on the growth of bacteria or other microorganisms.  相似文献   

12.
In continuing our efforts to find new effective antimicrobial agents for overcoming the problem of microbial resistance, a new series of functionalized 5-hetarylthiazoles have been designed and synthesized starting from readily accessible 1-(2-allylamino-4-methylthiazol-5-yl)ethanone (3). The structures of newly synthesized compounds were confirmed by elemental analyses, spectral data, and chemical transformations. The synthesized compounds were evaluated in vitro for their antimicrobial activity against some human pathogenic bacterial and fungal strains. The compounds 7, 18, and 24 exhibited higher antibacterial activity with minimum inhibitory concentration (MIC) values ranging from (0.03–0.06?µg/mL) than ampicillin (MIC, 0.12?µg/mL) against Streptococcus pneumoniae. Whereas compounds 4, 22, and 24 revealed higher antifungal potency than amphotericin B against Aspergillus fumigatus. The structure and antimicrobial activity relationship was also discussed.  相似文献   

13.
Abstract

A new cyclic pentapeptide, pentaminolarin (1), and a new cytochalasin, xylochalasin (2), along with thirteen known compounds (315) were isolated from the wood-decaying fungus Xylaria sp. SWUF08-37. The absolute configurations of 1 were determined by a combination of Marfey’s method and TDDFT ECD calculation and the absolute configurations of 2 were established by TDDFT ECD calculation. Compound 12 showed moderate cytotoxicity against HeLa (IC50?=?19.60?µg/mL), HT29 (IC50?=?17.31?µg/mL), HCT116 (IC50?=?14.28?µg/mL), MCF-7 (IC50?=?15.38?µg/mL), and Vero (IC50?=?24.97?µg/mL) cell lines by MTT assay. Compounds 1 and 2 showed slight cytotoxicity against all tested cancer cell lines.  相似文献   

14.
Abstract

The CHCl3 fraction of MeOH extract of Periploca somaliensis (family Asclepiadaceae) fruits afforded a new scalarane sesterterpene, namely perisomalien A (1), along with lupeol acetate (2), β-amyrin (3), cycloart-23Z-ene-3β,25-diol (4), and β-sitosterol-3-O-β-D-glucopyranoside (5). Their chemical structures were established by various spectroscopic analyses, in addition to comparison with the formerly reported data. Moreover, the cytotoxic activity of these metabolites was assessed towards MCF-7, HepG2, and HCT-116 tumour cell lines using sulforhodamine B (SRB) assay. Compound 4 showed the most potent cytotoxic profile with IC50 9.0?µM towards MCF-7, compared to doxorubicin (IC50 0.18?µM). Also, 1 and 4 possessed the most potent effect towards HepG2 with IC50s 26.7 and 25.9?μM, respectively. In addition, all tested compounds showed cytotoxic effects with IC50 values ranging from 19.9 to 39.3?µM against HCT-116.  相似文献   

15.
An efficient method for the simultaneous profiling analysis of 44 fatty acids including 24 aliphatic, 12 hydroxyl, and eight methyl-branched fatty acids as tert-butyldimethylsilyl (TBDMS) derivatives was developed by gas chromatography–mass spectrometry. In this study, new mass spectral databases of isolauric, 11-methyllauric, isomyristic, isopentadecylic, isopalmitic, isostearic, 17-methylstearic, and 19-methylarachidic acids were constructed as TBDMS derivatives. Under the optimal conditions, linearity in the range of 0.1–10.0?µg/mL (24 aliphatic fatty acids) and 0.01–1.0?µg/mL (eight methyl-branched and 12 hydroxy fatty acids) showed good correlation coefficients (r?≥?0.997). The repeatability showed relative standard deviation of less than 11.2% and accuracy (percent relative error) varied from ?11.0 to 7.8 for the 44 fatty acids studied. The recoveries ranged from 61.7 to 90.1% with good repeatability. When applied to human plasma sample, 18 aliphatic, three 2-hydroxy, three 3-hydroxy, and five methyl-branched fatty acids were positively identified and quantified. Therefore, the present method will be useful for profiling analysis of various fatty acids in biological samples including plasma.  相似文献   

16.
Phytochemical investigations of different species of Lamiaceae family (rosemary-Rosmarinus officinalis L., sage-Salvia officinalis L., winter savory-Satureja montana L., clary sage-Salvia sclarea L. and sticky sage-Salvia glutinosa L.), using gas chromatography and mass spectrometry (GC-MS) were performed. The studies were focused on oleanolic, betulinic and ursolic acid. Since oleanolic and ursolic acid are position isomers with very similar structures, the difficulties in their separation and identification have been reported by several authors. However, both compounds can be well distinguished by order of elution during gas chromatography and by intensities of the fragment ion signals in their mass spectra, where the retro-Diels-Alder reaction was primarily observed. A combination of ultrasonic extraction, solid phase extraction, size exclusion chromatography, trimethylsilylation, and GC-MS resulted in simultaneous separation, identification and quantification of the mentioned compounds. The compounds have been identified by retention time and comparison of mass spectra with those of pure standards. The mass spectral fragmentation behavior of all three derivatised acids was investigated. The obtained characteristic fragment patterns are discussed in the presented work. Good linearity over the concentration range 1–50 mg L−1 for all three compounds was confirmed. The correlation coefficients (r 2 ) were in the range of 0.9980–0.9983. Quantitative analyses of different Lamiaceae extracts showed that the oleanolic acid content ranged from 0.09 to 0.9% dry weight, content of betulinic acid ranged from traces to 0.6%, and that of ursolic acid varied from 0.09 to 1.6% dry weight.  相似文献   

17.
Seaweed, biologically and phycologically referred to as algae, is classified as Rhodophyta (red), Chlorophyta (green), and Ochrophyta (brown). In this study, the concentrations of 13 elements (As, Ca, Cd, Co, Cr, Cu, Fe, Mg, Mn, Ni, Pb, Se, and Zn) were investigated for 14 seaweed species of varying classes (Amphiroa bowerbankii, Ceramium virgatum, Dichotomaria tenera, Ellisolandia (Coralline) elongata, Gelidium abbottiorum, Gracilaria canaliculata, Jania rubens, and Jania (Haliptylon) squamata of the Rhodophyta (red); Caulerpa filiformis, Codium capitatum, Halimeda cuneata, and Ulva rigida of the Chlorophyta (green); and Cystoseira myrica and Sargassum elegans of the Ochrophyta (brown) to determine the nutritional value of seaweed based on its medicinal properties, industrial importance, and natural abundance. The elemental distribution in seaweeds was in decreasing order of Ca?>?Mg?>?Fe?>?Cu?>?Mn?>?Zn?>?Cr?>?Co?>?Se?>?As?>?Pb?>?Ni?>?Cd. All edible species contained high levels of macro and microelements with the corali sp. accumulating high levels of Ca. Of the edible seaweeds characterized, only three (G. abbottiorum, E. (Coralline) elongate and C. virgatum) are suitable for human consumption due to high levels of As, Cd, and Pb present in the other species. These three species are also rich in essential nutrients, specifically C. virgatum, which is high in Cu and Se. Hierarchical cluster analysis showed a clear similarity in distribution of essential and toxic elements in similar classes of seaweed.  相似文献   

18.
Abstract

Two new p-terphenyls, neonambiterphenyls A and B (12), a new benzoquinone, neonambiquinone A (3), together with six known sesquiterpenes (49), were isolated from the bioluminescent mushroom Neonothopanus nambi PW3. The isolated compounds were identified by mass, IR and spectroscopic analyses (1D and 2D NMR). Compounds 13 and 57 showed cytotoxicity against cancer cell lines such as KB, NCI-H187 and MCF-7 with IC50 values ranging from 1.45 to 49.31?µg/mL. In addition, compounds 1 and 5 showed cytotoxicity against Vero cells with IC50 values of 38.72 and 32.90?µg/mL, respectively.  相似文献   

19.
Abstract

Aloe vera leaf contains some bioactive compounds that have a strong binding affinity toward estrogen receptor as compared to standard drug tamoxifen. In this study, we have found that the IC50 of Aloe vera leaf extract against breast cancer cell line (MCF-7) is 23?µg/mL which is much lower than the IC50 (332?µg/mL) of Aloe vera leaf extract against non-cancerous cell line (NIH-3T3). We have also calculated the total concentration of phenolic acid (385.662?µg/mL), flavonoids (160.402?µg/mL) and alkaloids (276.754?µg/mL) in Aloe vera leaf extract. The free radical scavenging activity of Aloe vera leaf extract is 67% to 89% (at 50 to 300?µg/ml). Our virtual molecular docking study suggests that bioactive compounds like Aloe-emodin (?8.8?Kcal/mol), 7-hydroxy-2,5 dimethylchromone (?7.5?Kcal/mol), Beta-sitosterol (?7.3?Kcal/mol) etc. have a greater binding affinity toward estrogen alpha receptor as compared to standard drug Tamoxifen (?6.4?Kcal/mol).

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20.
《Analytical letters》2012,45(1):122-139
Abstract

Species of Garcinia (Guttiferae) are used for flavoring curries, as a supplement, and to treat various diseases. This study describes the comparison and discrimination of Garcinia cambogia, Garcinia indica, Garcinia mangostana and Garcinia atroviridis fruits by analyzing their major phytochemicals, elemental content, antioxidant, antidiabetic, and anticholinesterase enzymes activities. For phytochemical and elemental profiling, ultraviolet (UV), near infrared/infrared (NIR/IR), inductively coupled plasma-optical emission spectroscopy (ICP-OES) and ICP-mass spectrometric (ICP-MS) techniques were used. The chemometric multivariate tests of linear discriminant and principal component analyses (LDA, PCA) were used to discriminate the subject fruit samples. Spectroscopic data showed resonances of phenolics and flavonoidal constituents present in the fruits. G. mangostana exhibited the highest phenolics (721.6 to 2815.3?µM GAE/g), whereas G. cambogia was rich in flavonoids (51.9 to 2709.2?µM QE/g). Anthocyanin (cyanidin-3-O-glucoside) evaluated by high performance liquid chromatographic was 9.01?mg/kg in G. mangostana fruit. In the analyzed fruits, Ca, K and Na were high, trace essential elements were at appreciable contents, whereas the toxic elements As, Cd, Tl, and Pb were within the safe limits. G. mangostana contained potent free radicals and cholinesterase enzyme inhibitors, whereas G. cambogia inhibited α-amylase enzyme more significantly. PCA and LDA discriminated the fruit samples with distinct classification and variability indices. The analyzed fruits were shown to be good sources of free radicals, cholinesterase, and α-amylase enzymes inhibition, mineral and essential elements, and safe for human consumption.  相似文献   

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