首页 | 本学科首页   官方微博 | 高级检索  
相似文献
 共查询到20条相似文献,搜索用时 109 毫秒
1.
A total of nine sesquiterpenoid lactones together with phenolic compounds and other terpenes were identified from the crude methanol extract of Elephantopus mollis Kunth. Compounds were isolated using different chromatographic techniques and their structures were determined by NMR and IR spectroscopy as well as mass spectrometry. The structures of some detected compounds were assigned based on LC-ToF-ESI-MS screening of main fractions/subfractions from flash chromatography and comparison with isolated analogues as standards. The findings revealed not only the in-source loss of water as the base peak in hirsutinolides but also the in-source loss of corresponding alcohol when the oxygen at position 1 is alkylated. The present study also draws up a complement of data with respect to hirsutinolide-like sesquiterpene lactones whose LC-MS characteristics are not available in the literature. The chemophenetic significance is also discussed. Some of the isolated compounds were reported for the first time to be found in the species, the genus as well as the plant family. The medium-polar fractions of the crude extract, also containing the larger amount of sesquiterpenoid lactones, exhibited activity both against a cancer cell line and bacterial strains. Isolated lactones were also active against the cancer cell line, while the chlorogenic derivatives also valuable in Elephantopus genus showed potent radical scavenging activity. This is the first report of cytotoxic and antibacterial activities of our samples against the tested strains and cell line. The present study follows the ongoing research project dealing with the characterization of taxa with antibacterial and antiparasitic activities from Cameroonian pharmacopeia.  相似文献   

2.
The phytochemical investigation on the chemical constituents of dichloromethane-methanol (1:1) stem-bark extract of Cola lateritia K. Schum. (Sterculiaceae) led to the isolation and characterization of five pentacyclic triterpenoids, one fatty acid and two phytosteroids. The compounds were identified as heptadecanoic acid (1), maslinic acid (2), betulinic acid (3), lupenone (4), lupeol (5), friedelin (6), β-stigmasterol (7) and ß-sitosterol-3-O-ß-D-glucoside (8). Their structures were determined by NMR analysis (1H, 13C, DEPT-135, COSY, HMBC and HSQC), high-resolution mass spectrometry (HR-ESI-MS) and comparisons with published data in the literature. This work, to the best of our knowledge, is the first isolation and identification of these compounds in pure forms from Cola lateritia. Also, compounds 13 are reported for the first time from Cola genus. In vitro antibacterial activity of the isolated compounds (18) and the crude extract were evaluated against Bacillus subtilis, Staphylococcus epidermidis, Enterococcus faecalis, Mycobacterium smegmatis, Staphylococcus aureus, Enterobacter cloacae, Klebsiella oxytoca, Proteus vulgaris, Klebsiella pneumonia, Escherichia coli, Proteus mirabilis and Klebsiella aerogenes with streptomycin, nalidixic acid and ampicillin as standard antibacterial drugs. Compound 2 was active against E. faecalis (MIC = 18.5 µg/mL), and it was 6.9 and 28 times lower and active than that of streptomycin (MIC 128 µg/mL) and nalidixic acid (MIC > 512 µg/mL) respectively. All the isolated compounds and crude extract showed significant activities against the tested bacterial strains.  相似文献   

3.
Entomopathogenic fungi are referred to as potential candidates as insect pest control agents. The objective of the study was to identify fatty acids and amino acids from Conidiobolus coronatus cultured on two different media. Each medium was extracted with ethyl acetate and its mixtures with isopropanol, acetonitrile and methanol. Analyses of fatty acids and amino acids of entomopathogenic fungus C. coronatus were performed by means of gas chromatography coupled with mass spectrometry. The analysis showed that the fungus C. coronatus produces the following groups of compounds: fatty acids and amino acids; α- and β-glucopyranose were also identified. The identified fatty acids included 12–20, 22 and 24 carbon atoms per chain. The highest content of fatty acids was detected in a mycelium sample cultured in a liquid minimal medium extracted with ethyl acetate. The lowest content of these organic compounds was identified in mycelium cultured in a liquid nutrient-rich medium extracted with ethyl acetate–methanol mixture. Fatty acids were found to account for 62.0 mass % to 94.4 mass % of all organic compounds in the analyzed mycelia. C18:1 acids were detected in the highest amounts when ethyl acetate was used as the extracting agent. The identified amino acids accounted for 4 mass % to 21 mass % of all organic compounds. Upon extraction of C. coronatus mycelium samples with the ethyl acetate—methanol mixture, two anomeric forms of glucose were also identified. An analysis of the studied material confirmed, that the entomopathogenic fungus C. coronatus is a very rich source of organic compounds, which might encourage its further research so as to identify an even larger number of compounds being produced by this species.  相似文献   

4.
The lipids of the tuberous roots ofMandragora turcomanica Mizger (fam. Solanaceae) have been characterized for the first time. By using CC, TLC, Ag+-TLC, UV and IR spectroscopies and mass spectrometry, 20 classes of lipids and lipophilic substances have been characterized. The main components of the acyl-containing lipids that were isolated were found to be triacylglycerols and glycolipids, and among the lipophilic compounds they were alkanols and sterols; in the mixture of fatty acids of the acyl-containing lipids the 18:2, 18:1, and 16:0 acids predominated.  相似文献   

5.
A novel method was developed for the analysis of molecular species in neutral lipid classes, using separation by normal phase high-performance liquid chromatography, followed by detection by evaporative light-scattering and electrospray ionization tandem mass spectrometry. Monoacid standards, i.e. sterol esters, triacylglycerols, fatty acids, diacylglycerols, free sterols and monoacylglycerols, were separated to baseline on microbore 3 μm-silica gel columns. Complete or partial separation of molecular species in each lipid class permitted identification by automatic tandem mass spectrometry of ammonium adducts, produced via positive electrospray ionization. After optimization of the method, separation and identification of molecular species of various lipid classes was comprehensively tested by analysis of neutral lipids from the free lipid extract of maize flour.  相似文献   

6.
A total of 20 of isolates of lactic acid bacteria (LAB) were selected and screened for antagonistic activity against clinical strains of 30 clinical isolates of extremely drug-resistant (XDR) Acinetobacter baumannii using the well diffusion assay method. Results showed that 50% of the highly LAB strains possessed inhibitory activity against (up to 66%) of the XDR A. baumannii strains tested. The supernatant of the twenty LAB strains was subjected to gas chromatography mass spectrometry (GCMS) revealed that the common compound found in the active isolates against XDR A. baumannii was 3-Isobutyl-2,3,6,7,8,8a-hexahydropyrrolo[1,2-a]pyrazine-1,4-dione, a known potential diketopiperazine group. The molecular docking study against potential antibacterial targets with selected ligands was performed to predict the binding mode of interactions, which is responsible for antibacterial activity. The docking analysis of the potent compounds supported the potential antibacterial activity exhibiting high inhibition constant and binding affinity in silico.  相似文献   

7.
Cystoseira (Sargassaceae) is a genus of marine brown algae composed of about 40 species, which is distributed along the Eastern Atlantic and Mediterranean coasts. The biological potential of the Cystoseira genus has been investigated and several activities have been reported. Chemically, this genus contains a wide variety of secondary metabolites, such as terpenoids, steroids, phlorotannins and phenolic compounds. Additionally, other chemical components as, for instance, carbohydrates, triacylglycerols/fatty acids, pigments as well as vitamins have been identified in the studied species. Some of the isolated compounds were associated with the reported pharmacological properties, as for example antioxidant, anti-inflammatory, cytotoxicity, anticancer, cholinesterase inhibition, anti-diabetic, activities but also antibacterial, antifungal and anti-parasitic activities. In this review, we provide a comprehensive overview of the compounds isolated and identified after 1995 from the different species of Cystoseira, compiling more than 200 compounds isolated, together with their therapeutic potential.  相似文献   

8.
Rodgersia aesculifolia Batal. rhizome is an effective antibacterial and antivirus Chinese medicinal plant. In this work focused microwave-assisted solvent extraction (FMASE) coupled with gas chromatography–mass spectrometry has been used for analysis of Rodgersia aesculifolia Batal. rhizomes. The main compound classes in the extract were fatty acids (67.22%), aliphatic hydrocarbons (9.02%), and steroids (7.02%). Oleic acid, linoleic acid, and palmitic acid were the most abundant compounds. Compared with Soxhlet extraction, the much shorter extraction time and the similar components in the extract make FMASE an excellent alternative for extraction of the components of plant rhizomes.  相似文献   

9.
The chemical composition of the hydroethanolic extracts (60% v/v) from the aerial parts of Thymus marschallianus Willd (TM) and Thymus seravschanicus Klokov (TS) from Southern Kazakhstan flora was analyzed together with their hexane fractions. Determination of antibacterial, antifungal and antioxidant activities of both extracts was also performed. RP-HPLC/PDA and HPLC/ESI-QTOF-MS showed that there were some differences between the composition of both extracts. The most characteristic components of TM were rosmarinic acid, protocatechuic acid, luteolin 7-O-glucoside, and apigenin 7-O-glucuronide, while protocatechuic acid, luteolin 7-O-glucoside, luteolin 7-O-glucuronide, and eriodictyol predominated in TS. The content of polyplenols was higher in TS than in TM. The GC-MS analysis of the volatile fraction of both examined extracts revealed the presence of thymol and carvacrol. Additionally, sesquiterpenoids, fatty acids, and their ethyl esters were found in TM, and fatty acid methyl esters in TS. The antioxidant activity of both extracts was similar. The antibacterial activity of TS extract was somewhat higher than TM, while antifungal activity was the same. TS extract was the most active against Helicobacter pylori ATCC 43504 with MIC (minimal inhibitory concentration) = 0.625 mg/mL, exerting a bactericidal effect. The obtained data provide novel information about the phytochemistry of both thyme species and suggest new potential application of TS as a source of bioactive compounds, especially with anti-H. pylori activity.  相似文献   

10.
Two compounds janoxepin (1) and brevicompanine B (2) were isolated from the fungus Aspergillus janus and the structures elucidated by one- and two-dimensional NMR spectroscopic methods and mass spectrometry. Janoxepin is a novel oxepin derivative with a rare d-leucine incorporated. Brevicompanine B has previously only been isolated from Penicillium brevicompactum. Both compounds were tested in antimicrobial assays and found to be active against the malaria parasite Plasmodium falciparum 3D7 (IC50-values of 28 and 35 mg/ml, respectively). However, no activity was observed in antifungal or antibacterial assays.  相似文献   

11.
Four different isolation techniques, conventional hydrodistillation (HD), microwave-assisted hydrodistillation (MWHD), microdistillation (MD) and micro-steam distillation-solid-phase microextraction (MSD-SPME), have been used to analyze the volatile constituents from the aerial parts of Salvia rosifolia Sm. by gas chromatography and gas chromatography coupled to mass spectrometry. HD and MWHD techniques produced quantitatively (yield, 0.39% and 0.40%) and qualitatively (aromatic profile) similar essential oils. α-Pinene (15.7–34.8%), 1,8-cineole (16.6–25.1%), β-pinene (6.7–13.5%), β-caryophyllene (1.4–5.0%) and caryophyllene oxide (1.4–4.4%) were identified as major constituents of this Turkish endemic species. Besides, the hydrodistilled oil of S. rosifolia was evaluated for antibacterial, antifungal, anticancer, antioxidant and cytotoxic activities. The hydrodistilled oil of S. rosifolia showed antibacterial activity against Methicillin-resistant Staphylococcus aureus (MRSA) with a MIC value of 125 μg/mL. Other human pathogenic microorganisms (Escherichia coli, Pseudomonas aeruginosa, Enterobacter aerogenes, Salmonella typhimurium, Staphylococcus epidermidis, Candida albicans) were also inhibited within a moderate range (MIC = 125–1000 μg/mL). Antifungal activity of the oil was also observed against the strawberry anthracnose-causing fungal plant pathogens Colletotrichum acutatum, C. fragariae and C. gloeosporioides. No cytotoxicity was observed for S. rosifolia oil up to 25 mg/mL against malignant melanoma, epidermal, ductal and ovary carcinoma.  相似文献   

12.
Sulfonamide‐derived compounds and their first row d‐transition metal chelates [cobalt(II), copper(II), nickel(II) and zinc(II)] have been synthesized and characterized. The nature of bonding and structure of all the synthesized compounds have been proposed from magnetic susceptibility and conductivity measurements, IR, 1H and 13C NMR, electron spectra, mass spectrometry and CHN analysis data. The structure of ligand, 4‐{[(E)‐(5‐chloro‐2‐hydroxyphenyl) methylidene] amino}‐N‐(4,6‐dimethyl pyrimidin‐2‐yl) benzene sulfonamide has also been determined by X‐ray diffraction method. An octahedral geometry has been suggested for all the complexes. The ligands and metal complexes have been screened for their in vitro antibacterial, antifungal and cytotoxic activity. The results of these studies revealed that all compounds showed moderate to significant antibacterial activity against one or more bacterial strains and good antifungal activity against various fungal strains. Copyright © 2009 John Wiley & Sons, Ltd.  相似文献   

13.
The ‘core’ metabolome of the Bacteroidetes genus Chitinophaga was recently discovered to consist of only seven metabolites. A structural relationship in terms of shared lipid moieties among four of them was postulated. Here, structure elucidation and characterization via ultra-high resolution mass spectrometry (UHR-MS) and nuclear magnetic resonance (NMR) spectroscopy of those four lipids (two lipoamino acids (LAAs), two lysophosphatidylethanolamines (LPEs)), as well as several other undescribed LAAs and N-acyl amino acids (NAAAs), identified during isolation were carried out. The LAAs represent closely related analogs of the literature-known LAAs, such as the glycine-serine dipeptide lipids 430 (2) and 654. Most of the here characterized LAAs (1, 5–11) are members of a so far undescribed glycine-serine-ornithine tripeptide lipid family. Moreover, this study reports three novel NAAAs (N-(5-methyl)hexanoyl tyrosine (14) and N-(7-methyl)octanoyl tyrosine (15) or phenylalanine (16)) from Olivibacter sp. FHG000416, another Bacteroidetes strain initially selected as best in-house producer for isolation of lipid 430. Antimicrobial profiling revealed most isolated LAAs (1–3) and the two LPE ‘core’ metabolites (12, 13) active against the Gram-negative pathogen M. catarrhalis ATCC 25238 and the Gram-positive bacterium M. luteus DSM 20030. For LAA 1, additional growth inhibition activity against B. subtilis DSM 10 was observed.  相似文献   

14.
Abstract

Eighteen compounds were isolated from the ethyl acetate fraction of the aerial part of Hyssopus cuspidatus. Their structures were established by analysis of mass and NMR data, as well as comparison with previous published data in the literatures. Among them, ten compounds were found from the Hyssopus genus for the first time, and one compound was isolated from H. cuspidatus for the first time. HPLC-DAD-ESI-HRMS/MS investigations was applied to further obtain the phenolic profiling of the ethyl acetate fraction, and nine derivatives of caffeic acid and ferulic or isoferulic acid were identified. Antioxidant activity against DPPH free radical and antibacterial activity against Candida albicans, Escherichia coli and Staphylococcus aureus were evaluated. The ethyl acetate fraction exhibited weak antioxidant activity and moderate antibacterial activity. The isolated compounds showed weak to potent antioxidant and antibacterial activity. To the best of our knowledge, this is the first report on the antioxidant and antibacterial activity of H. cuspidatus.  相似文献   

15.
Salicornia species have just been introduced to the European market as a vegetable named ‘samphire’, ‘green asparagus’, or ‘sea asparagus’. Due to its increasing attention, and associated value, minor compounds of Salicornia gaudichaudiana Moq were investigated. The use of countercurrent chromatography and mass spectrometry enabled the search for known, as well as potentially novel natural products. Their identification was achieved based on molecular weights and mass‐spectrometric fragmentation data. Low detection limits enabled the visualization of all compounds with their identification in almost real time close to the preparative countercurrent chromatography experiment. A list of known natural products from Salicornia genus guided the identification process of compounds occurring in Salicornia gaudichaudiana Moq by tandem mass spectrometry fragment comparison. The natural product classes were divided into four groups: chlorogenic acid derivatives; flavonoid derivatives; pentacyclic triterpenoid saponins; and other compounds.  相似文献   

16.
The effect of four synthetic media containing glucose (initial concentration 30?g?l?1) on mycelial growth, exopolysaccharides (EPS) and cellular lipids production was examined in 11 mushroom species after 12 and 16?days of culture in static- and shake-flasks. Fatty acid analysis of cellular lipids produced was also performed. Agitation had a positive effect on biomass production, glucose consumption and lipid biosynthesis. Media that favoured the production of biomass were not suitable for EPS biosynthesis and vice versa. Biomass values varied from ??1.0?g?l?1 (Lentinula edodes) to ??19?g?l?1 (Pleurotus ostreatus), while the highest EPS quantity achieved ranged between 1.6 and 1.8?g?l?1 (for Ganoderma lucidum and L. edodes, respectively). Quantities of total cellular lipids varied between 2.5 and 18.5?% w/w, in dry mycelial mass for the fungi tested. Lipid in dry weight values were influenced by the medium composition. Cellular lipids presented noticeable quantities of poly-unsaturated fatty acids like linoleic acid. Compared to most of the mushrooms tested, lipids of Volvariella volvacea were more saturated. The ability of several mushroom species of our study to produce in notable quantities the above-mentioned added-value compounds renders these fungi worthy for further investigations.  相似文献   

17.
Several Acalypha australis Linn. species are used in traditional medicine in Southeast Asia. In this work, the ultra‐performance liquid chromatography/mass spectrometry fingerprints and the antibacterial activities of A. australis Linn. were investigated. An in‐depth discussion on the reliability of identifying and obtaining potentially active compounds by spectrum‐effect relationship and semi‐preparative high performance liquid chromatography was conducted. The result shows that gallic acid and a compound with molecular weight of 634.1 in the fingerprints were the main antibacterial compounds. Compared to the crude extract of A. australis Linn., both compounds increase the antibacterial efficacy 10 to 20 times. Compounds with molecular weights of 154.0, 292.0, and 485.1 in the fingerprints were the auxiliary antibacterial compounds. Through the entire isolation procedure, we obtained these antibacterial compounds with purities of 92.53, 87.98, 90.73, 89.36, and 88.14%, respectively. This work provides a general model of the combination of ultra‐performance liquid chromatography/mass spectrometry fingerprinting and antibacterial test to study the spectrum‐effect relationships of A. australis Linn. This model can be used to discover further the active compounds of this herb.  相似文献   

18.
Many Violaceae plants contain cyclotides, which are plant cyclopeptides distinguished by a cyclic cystine knot motif with 28–37 amino acid residues. In the current study, four new cyclotides, vila A–D ( 1 – 4 , resp.), together with a known cyclotide, varv D ( 5 ), were isolated from Viola labridorica (Violaceae). A chromatography‐based method was used to isolate the cyclotides, which were characterized using tandem mass spectrometry and 2D‐NMR spectroscopy. Several of the cyclotides showed cytotoxic activities against five cancer cell lines, i.e., U251, MDA‐MB‐231, A549, DU145, and BEL‐7402, with vila A and B ( 1 and 2 , resp.) being the most cytotoxic. The isolated cyclotides showed no antibacterial activity against Staphyloccocus aureus and Candida albicans. Homology modeling of the cyclotide structures was used to analyze structure–activity relationships.  相似文献   

19.
Fast-atom-bombardment mass spectrometry (FABMS) is used for the semiquantitative determination of the fatty acids of complex lipids directly from intact algal cells, crude algal lipid extracts, and vegetable oils. Carboxylate ions, RCOO?, corresponding to the fatty acid moieties of the complex lipids are detected. The relative abundances of the carboxylate fatty acid ions in the FAB mass spectra agreed with the relative percentages found by gas chromatography of the fatty acid methyl esters derived from the extracted lipids. Chemical ionization/fast-atom-bombardment mass spectrometry (CI/FABMS) is discussed with respect to enhancing the molecular ions of the fatty acids and triacylglycerols from these materials. The use of FABMS requires little sample preparation, and FABMS enables rapid fatty acid screening, directly from crude biological materials.  相似文献   

20.
Infections with Chlamydia pneumoniae cause several respiratory diseases, such as community-acquired pneumonia, bronchitis or sinusitis. Here, we present an integrated non-targeted metabolomics analysis applying ultra-high-resolution mass spectrometry and ultra-performance liquid chromatography mass spectrometry to determine metabolite alterations in C. pneumoniae-infected HEp-2 cells. Most important permutations are elaborated using uni- and multivariate statistical analysis, logD retention time regression and mass defect-based network analysis. Classes of metabolites showing high variations upon infection are lipids, carbohydrates and amino acids. Moreover, we observed several non-annotated compounds as predominantly abundant after infection, which are promising biomarker candidates for drug-target and diagnostic research.  相似文献   

设为首页 | 免责声明 | 关于勤云 | 加入收藏

Copyright©北京勤云科技发展有限公司  京ICP备09084417号