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1.

Gradient ion chromatographic separation coupled with ICP-MS was used to resolve and determine the most common arsenic species in environmental and biological samples of carrots, trout, soil, sediment and river water from Region II of Chile. The carrot and trout samples showed a concentration of 49 and 168 µg g?1, respectively, of total As. Both concentrations are high considering the basal level. In the carrots, percentage of 45 and 31% of total As were found for As(III) and As(V) species, respectively. In the trout, the higher concentration related to AsB at 39% of the total As. As(III) and DMA were also present in relatively high concentrations. The River Loa and the soil in which the carrots are growing also present very high As(V) concentrations of 100 and 17 µg g?1, respectively. The ratio between the concentration for the same As species found in the living organisms (carrots and trout) and the environment in which they grow (soil and water) can provide important information about the possible absorption or biotransformation of As species in living beings. As(III) and DMA are the species in which the greatest accumulation occurs with respect to the medium in which they are present, and biotransformation also appears to take place.  相似文献   

2.
Senecio nutans Sch. Bip., S. viridis var. viridis Phill. and S. spegazzinii Cabrera are native species used in traditional medicine of northwestern Argentina. The total phenolics, flavonoids and caffeoylquinic acids contents, as well as radical scavenging, antioxidant, hemolytic and cytotoxic activities of aqueous extracts (infusion and decoction) of all three species were determined. S. nutans was the most active. The extracts did not show antibacterial activity. Alkaloids were not detected in any of the aqueous extracts of the three studied species.  相似文献   

3.
This research investigated the effects of control release of binders that are used in the pills of Chinese herbal medicine, namely, as processed honey, starch paste, beeswax, or mixtures thereof. Aspirin and baicalin were used as the active pharmaceutical ingredients (API). The processed honey was heated to 110 degrees C, 120 degrees C, or 130 degrees C. In these pills, the binders were the only excipients. The pills were prepared by the stir method using a mixer at 80 degrees C without pressure. The differential thermal analysis (DTA) showed that the melting points of aspirin and baicalin were changed by the binders. The Fourier Transform infrared spectra (FT-IR) of aspirin and baicalin suggest that there are different non-covalent molecular interactions between the API and the binders, such as C-H-pi and hydrogen bond interaction. The dissolution profiles indicate that changing the ratio of the binders altered the patterns of dissolution of the API; thus, this ration may be used to control the release of API from the pills.  相似文献   

4.
This study examines the in vitro antimicrobial and antioxidant activities of the methanolic extracts of three Salvia species from Tunisia: Salvia aegyptiaca L., S. argentea L. and S. verbenaca Ssp. clandestina L. Pugsley. The extracts inhibited the growth of dermatophytes and of bacteria responsible for unpleasant odours to varying degrees; the pathogenic yeasts Candida albicans and Cryptococcus neoformans, the filamentous fungi Aspergillus fumigatus and selected dog otitis bacteria were all resistant to each of the extracts. The extracts were screened for their antioxidant activities using 2,2-diphenyl-1-picrylhydrazyl free radical scavenging and 2,2'-azinobis(3-ethylbenzothiazoline-6-sulphonic acid) test systems, and gave positive results in both tests. The extracts of S. aegyptiaca were the most active in both tests, followed by those of S. verbenaca, then S. argentea. These results confirm the antimicrobial and antioxidant activities of the genus Salvia and underline the potential of these plants either as natural preservatives or in pharmaceutical applications.  相似文献   

5.
《Comptes Rendus Chimie》2016,19(9):1056-1061
Cinnamosma fragrans is an endemic plant used in traditional medicine. The geographical distribution of this Canellaceae is limited to Madagascar. Few phytochemical investigations performed on this plant have described atypical sesquiterpenes including drimane-type sesquiterpenes, drimane-type sesquiterpene lactones, sesquiterpene lactams and coloratane sesquiterpenes. These original sesquiterpenes are associated with pharmaceutical activities.  相似文献   

6.
The essential oil of the leaves of Pistacia lentiscus, collected from the middle Atlas in Morocco, was analyzed by GC and GC-MS. Altogether 43 components in concentrations of more than 0.2% were identified representing 97.4% of the oil composition. The main constituents were germanicol (12.8%), thunbergol (8.8%), himachalene (7.4%), trans-squalene (6.7%), terpinyl propionate (6.7%), 3,3-dimenthol (6.2%) and cadina-1.4-diene (5.1%). The oils showed strong activity against Klebsiella pneumonia, but no activity against Pseudomonas aeruginosa.  相似文献   

7.
Three phenylpropanoids (ferulic acid, chlorogenic acid, and caffeic acid) are simultaneously separated and determined within 13 min by a new capillary electrophoresis method using 15 mmol/L sodium borate (pH 8.71) as run buffer. The optimum conditions for the separation as well as the analytical characteristics, such as the calibration graph and limit of detection (LOD) for the determination of these three compounds, are studied. The linear range for the determination of ferulic, chlorogenic, and caffeic acid is 5.0 approximately 70.0, 8.0 approximately 112.0, and 9.0 approximately 64.0 microg/mL, with the LOD as 1.5, 2.25, and 6.0 microg/mL, respectively. The method, which is very simple, rapid, and of requisite sensitivity and reproduction, is satisfactorily used for the separation and determination not only of ferulic, chlorogenic, and caffeic acid in Cimicifuga foelida Li and its preparation (Yin-huang-han-pian), but also of ferulic acid and chlorogenic acid in Ligusticum chuanxiong hort. and Angelica sinensis (Oliv.) Diels.  相似文献   

8.
LC-ESI-MS/MS was used for a comprehensive characterisation of ethanol extract from the leaves of three Pistacia species. After optimisation of the method and the use of the negative ionisation mode, a total of 42 different compounds were identified, of which 22 were tentatively characterised in P. chinensis Bunge, 33 in P. khinjuk stocks and 25 in P. lentiscus L. leaves. Flavonoids, phenolic acids, and their derivatives were the most abundant identified compounds. LC-ESI-MS/MS revealed identification of 15, 18 and 6 not previously detected compounds in P. chinensis Bunge, P. khinjuk Stocks and P. lentiscus L., respectively. The three extracts were also tested for their cytotoxic activities against human PC3 prostate cancer, A549 lung cancer, MCF7 breast cancer and HepG2 liver cancer. Generally, all the extracts have a moderate cytotoxic activity against lung, breast and prostate cancer, with different IC50. However, only P. lentiscus L. showed moderate activity against liver cancer.  相似文献   

9.
The term lipo-alkaloid is used for C19 aconitane alkaloids containing one or two long-chain fatty acid residues. Lipo-alkaloids are transesterified derivatives of the most toxic and highly effective diester-type diterpene alkaloids, such as aconitine, hypaconitine, mesaconitine. Lipo-alkaloids are native minor compounds of aconite drugs, but their amount significantly increases after traditional processing, which is a general method in the Far Eastern traditional medicinal systems. Analytical works demonstrated that cautious processing (usually boiling) of crude aconite roots decreases the amount of normal diterpene alkaloids and increases the concentration of lipo-alkaloids resulting in the reduction of toxicity of the drugs. Many papers reported that lipo-alkaloids occur as a complex mixture in the drugs, and the isolation of the individual components is extremely difficult. These compounds have been identified using highly sensitive analytical methods (HPLC-MS, NMR), and semisynthetic approaches have been developed to ensure lipo-alkaloids in pure form for pharmacological studies. This review summarizes the structure, chemistry, semisynthesis, analytics and bioactivities of lipo-alkaloids. On the basis of 32 references this is the first comprehensive study on this topic, covering the data of 173 compounds.  相似文献   

10.
Prolyl hydroxylase domain 2 (PHD2) is a key enzyme regulating the expression of hypoxia inducible factor (HIF). Its inhibitors can improve the expression of HIF and downstream genes, which can treat hypoxia-related diseases. Therefore, the establishment of a reliable PHD2 inhibitors screening method is of great significance for the drug development of hypoxia-related diseases. In this work, an accurate, rapid, and simple screening method for PHD2 inhibitors was introduced by capillary zone electrophoresis (CZE). In order to improve the detection sensitivity, the derivative reaction of α-ketoglutaric acid (α-OG) and 1,2-diaminobenzene (OPD) was used to enhance the UV absorption of α-OG (the substrate in the enzymatic reaction). The CZE method selected 20 mM Na2B4O7 buffer (pH 9.0) as the separation buffer, +25 kV as the separation voltage, 25°C as the cartridge temperature, and 210 nm as the detection wavelength. Under this condition, the analysis of a single sample can be realized within 9 min. Compared with the existing reported methods, the present work can directly screen the PHD2 inhibitory activity of traditional Chinese medicine (TCM) extracts, which is of significance for the target-purification of bioactive individual compounds from TCMs. Under the optimal conditions, the PHD2 inhibitor screening platform was successfully established, and it was found that 70% methanol/water extracts of Astragali Radix and Codonopsis pilosula had good PHD2 inhibitory activity. Furthermore, the present work provides a novel approach for screening the PHD2 inhibitory activity of TCM extracts and the discovery of anti-hypoxia bioactive compounds.  相似文献   

11.
《Comptes Rendus Chimie》2002,5(3):163-169
The pursuit of antimicrobially active compounds against a variety of microorganisms is an area of intense and important research. In the present study, we examined the relative antimicrobial activity of calixarenes having different side chains, moieties and/or substitution groups against a diverse set of bacteria and fungi. Antimicrobial activity against the various species was evaluated by growth rate and inhibition rate comparisons to distinguish between the compounds for this desired property. Preliminary screening of 57 calixarenes was conducted to assay their potential as antimicrobially active compounds against Corynebacterium. Of these compounds, seven calixarenes numbered 25, 26, 27, 28, 30, 34 and 50 were found to exhibit suitable antimicrobial activity. These seven samples were then further tested to elucidate any antimicrobial activity they might have versus additional species. After examining the growth and inhibition values of these selected compounds, calixarenes sample numbers 25, 26, 27, 28 and 50 were shown to also display antimicrobial activity against Fusarium solani f. sp. mori 〚F.s.-26〛 with an inhibition range of approximately 60–70%. Additionally, sample numbers 25, 26, 27, and 28 exhibited excellent and selective antimicrobial activity against the fungal strains, Rosellinia necatrix 〚R-8〛, and Colletotrichum dematium 〚C.d. 8901〛.  相似文献   

12.
Alzheimer's disease (AD), characterized by the death of nerve cells in the cerebral cortex, is the most common subtype of dementia. Despite the exponential growth in the number of AD patients, acetylcholinesterase (AChE) inhibitors are currently used to treat AD. Plants of the Amaryllidaceae family are known to synthesize a particular type of bioactive compounds, named Amaryllidaceae alkaloids, which have shown AChE inhibitory activity. Alkaloid extracts of three species of Amaryllidaceae were studied with respect to their acetylcholinesterase and butyrylcholinesterase inhibitory activity and alkaloid patterns. Eleven alkaloids were identified by GC/MS. Significant cholinesterase inhibitory activity was demonstrated by the alkaloid extract of N. undulata (IC50,(HuAChE) = 14.3 +/- 1.2 microg/mL; IC50,(HuBuChE) = 33.9 +/- 1.9 microg/mL).  相似文献   

13.
Antimicrobial activity of hydroxamic acids   总被引:2,自引:0,他引:2  
  相似文献   

14.
15.
Poly(vinyl chloride)-pyrazolone; PVC-pz as a new modified form of PVC with high antibacterial and antifungal activities towards some Gram +ve bacteria S. Aureus, B. Subtilis and S. Faecalis) and Gram –ve bacteria (E. Coli, P. Aeruginosa and N. Gonorrhoeae) beside Candida albicans in addition to Aspragillus flavus as fungi has been synthesized in absence and in presence of silver-nanoparticles, AgNPs, in 3 and 5% by weight with respect to PVC. This was developed by a chemical reaction of PVC 1, and pyrazolone 2 in tetrahydrofuran, THF as solvent. PVC-pz derivative has been characterized by FTIR, 1HNMR spectroscopic analyses, in addition to scanning and transmission electronic microscopy. Photostability of PVC-pz was evaluated by following the discoloration for UV- irradiated samples colorimetrically in accordance with degradation time. IR and 1H-NMR analyses confirm that PVC-pz, 4 was formed indicating a substitution reaction of chlorine atoms of PVC chains to the hydrogen atom of active methylene and that attached to pyrazolone nitrogen at the same time. Antimicrobial activities of PVC-pz increased in the presence of AgNPs and with increasing its percentage.  相似文献   

16.
建立了虎杖苷在碳纳米管修饰玻碳(CNT/GC)电极上的电化学检测方法。在0.2 mol/L HCl溶液中,用方波溶出伏安法研究了虎杖苷在CNT/GC电极上的电化学行为。虎杖苷在+0.83V(vs.Ag/AgCl)电位处产生一个阳极氧化峰,峰电流与虎杖苷的浓度在7.0×10-7~4.0×10-5mol/L范围内呈良好的线性关系,最低检测限达4.57×10-7mol/L。方法可用于生药材和中成药中虎杖苷的测定。  相似文献   

17.
A new oxidosqualene cyclase (OSC) cDNA was cloned from the roots of Stevia rebaudiana. Functional expression in yeast and spectral analyses of the products established that the obtained OSC yields baccharis oxide as the major product. This is the first identification of an OSC yielding baccharis oxide. This result clearly demonstrated that baccharis oxide, a baccharane triterpene with a unique 3,10-oxide bridge in the A-ring, is a direct product from oxidosqualene by an OSC.  相似文献   

18.
The results are given of an investigation of three species of the genusHaplophyllum: H. villosum, H. kowalenskyi, andH. tenue, fromwhich five substances of coumarin nature have been isolated. Of them, two substances (I and II) have been identified as scopoletin and lomatin isovalerate, respectively, while suitable structures have been established for the new compounds tenuidin, villosin, and tenudiol. It has been shown that the coumarin composition of the plants changes with the growth site.  相似文献   

19.
Ten new derivatives of isophorone were obtained through a five-step synthesis. Among the products were several unsaturated, bicyclic lactones with three or four methyl groups. These lactones were used as the substrates for biotransformation mediated by selected fungal strains (Fusarium species, Syncephalastrum racemosum, Cunninghamella japonica, Penicillium species, Absidia species, and Pleurotus ostreatus). Four new hydroxylactones were obtained as a result of biotransformation. Because the unsaturated lactone with four methyl groups was a diastereoisomeric mixture, a structural analysis was conducted. The hydroxylactones were also included in this analysis. Both the unsaturated lactones and hydroxylactones were examined for their antimicrobial activity. It was found that some of these compounds exhibited growth inhibition against pathogenic strains of bacteria (Staphylococcus aureus, Pseudomonas fluorescens), yeasts (Candida albicans) and filamentous fungi (Alternaria sp., Penicillium sp.). All obtained compounds were also subjected to scent analysis.  相似文献   

20.
Chemometrics and modernization of traditional Chinese medicine   总被引:1,自引:0,他引:1  
Development of chromatographic fingerprinting and its related chemometric methods in the research of quality control of traditional Chinese medicines(TCMs) are discussed. The quality control methods for guarantying the authentication and stability of products and semi-products of TCMs are firstly assessed. The technique based on chromatographic fingerprinting is essentially a kind of high-through put and integral tools to explore the complexity of herbal medicines. In order to further control the comprehensive quality of TCMs,confirmation and identification of their important chemical components are necessary. Some new strategies are proposed to trace the chemical changes of chromatographic fingerprints both in product processing and/or after their administration by modern chromatographic techniques and chemometrics. Combined with systems biology and bioinformatics,it seems possible for one to reveal the working mechanism of TCMs and to further control their intrinsic quality comprehensively.  相似文献   

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