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1.
The electrochemical behaviour of lawsone at glassy carbon electrode (GCE) was investigated by using cyclic and differential pulse anodic stripping voltammetric (DPASV) techniques. Cyclic voltammetry was used to study the influence of pH on the peak current and peak potential. The Mcllavnie’s buffer of pH 3.0 was selected as a suitable analytical medium in which lawsone exhibited sensitive diffusion controlled redox peaks (vs. Ag/AgCl). The peak current varied linearly with lawsone concentration in the range between 0.60 and 1.40 μM with a detection limit of 6 nM. The applicability of the proposed method was illustrated by the determination of lawsone present in real samples. A mean recovery of lawsone in the leaf of Lawsonia inermis was 99.5% with a relative standard deviation of 1.15%.  相似文献   

2.
Dyeing behavior of gamma irradiated cotton fabric using Lawson dye extracted from henna leaves has been investigated. Cotton and dye powder are irradiated to different absorbed doses of 2, 4, 6, 8 and 10 kGy using Cs-137 gamma irradiator. The dyeing parameters such as dyeing time, electrolyte (salt) concentration and mordant concentrations using copper and iron as mordants are optimized. Dyeing is performed using un-irradiated and irradiated cotton with dye solutions and their color strength values are evaluated in CIE Lab system using Spectraflash –SF650. Methods suggested by International Standard Organization (ISO) have been employed to investigate the colourfastness properties such as colourfastness to light, washing and rubbing of irradiated dyed fabric. It is found that gamma ray treatment of cotton dyed with extracts of henna leaves has significantly improved the color strength as well as enhanced the rating of fastness properties.  相似文献   

3.
The aim of this work was to provide a characterisation of volatile constituents from different commercial batches of henna (Lawsonia inermis) leaves of different geographic origin. Headspace solid-phase microextraction (HS-SPME) coupled with gas chromatography–mass spectrometry (GC–MS) was used for the purpose. A total of 72 components were identified by GC–MS in the headspace of different henna samples which proved to differ considerably from each other, because they were characterised by different classes of components, mainly aliphatic compounds (9.0–64.7%), terpenoids (5.8–45.5%) and aromatics (7.9–45.2%), with alkanes (0.9–18.5%), aldehydes (2.1–18.8%) and carboxylic acids (3.1–29.3%), monoterpenes (3.4–30.0%) and sesquiterpenes (0.8–23.7%) and phenyl propanoids (0.6–43.1%), being the most abundant, respectively. Major representatives of these groups were n-hexadecane (0.5–4.7%), (2E)-hexenal (0.5–11.7%) and acetic acid (2.8–24.5%), limonene (0.8–14.7%), carvol (3.8–7.1%), geranyl acetone (1.4–7.9%) and (E)-caryophyllene (3.3–8.4%), and (E)-anethole (0.6–35.0%), respectively. We assume that factors such as the manufacturing process, the storage conditions and the different geographic origin of the samples may contribute to such variability.  相似文献   

4.
Leaf samples of Lawsonia inermis (Li) were examined for their antimicrobial potential. Broth extracts in different concentrations were prepared and bioassayed in vitro for the growth of Escherichia coli. The growth of E. coli pathogen was inhibited to various degrees by increasing the concentration of the herbal powder. In addition to the observed alterations which were detected electrophoretically in the protein pattern, were activities of the amylase enzyme and glycoprotein fractions. The protein pattern has one common band of Rf 0.47 and two characteristic bands of Rf 0.36 and Rf 0.42 for E. coli sample. The quantitative mutation was observed in the bacteria with different concentrations of L. inermis compared with the control. Some types of proteins in E. coli completely disappeared upon being S.I affected. The amylase pattern showed one common band with Rf 0.037 and two characteristic bands with Rf 0.18 and Rf 0.37 for E. coli sample. The obvious quantitative mutation observed in bacteria with different concentrations of L. inermis compared with E. coli. The glycoprotein pattern recorded one common band at R1 with Rf 0.94 for E. coli sample and bacteria inoculated with different concentrations of L. inermis. These results confirmed the antibacterial activity of henna leaves and supported the traditional use of the plant in therapy of bacterial infections and disturbances that occurred at the biochemical level. The broth extract of the L. inermis leaves showed obvious antibacterial activity against E. coli.  相似文献   

5.
A new obtusafuran derivative, lawsonicin ( 1 ), and a new naphthaquinone, lawsonadeem ( 2 ), along with a known constituent, vomifoliol ( 3 ), were isolated from the aerial parts of Lawsonia alba and characterized by chemical transformation and spectroscopic experiments, including 2D‐NMR techniques.  相似文献   

6.
7.
The ability of the monoclonal antibody TU-20 and its scFv fragment to bind specifically to the C-end of the class III β-tubulin makes these substances useful as potential diagnostics for neurodegenerative diseases—especially peripheral neuropathies. TU-20 and its scFv were labeled with 125I and 123I by chloramine-T (with radiochemical yield 75 and 50%, respectively). Radiochemical purity and stability was revealed by gel filtration (decrease to 80 and 50% in 2 months, respectively). Immunoreactivity of the labeled TU-20 was determined by ELISA—the range of the preserved immunoreactivity varies from 60 to 95% in accordance to the used radiolabeling process. RIA and affinity coupling analytic methods were specifically designed with focusing on specifics of the antibody and its fragment. The results of RIA differ in depandance on the type of the reaction vessel (glass or polystyrene) and the affinity coupling results depend on the experimental arrangement—in the batch or on the column. Fragmentation of the labeled antibody and its fragment was estimated by bis–tris gel electrophoresis followed by silver staining and autoradiography (over 95% of radioactivity bound in the substances). The antibody binding in tissue slices was studied in vitro by immunohistochemistry. The Purkinje cells were observed conjugated with the radiolabeled substances, either TU-20 or its ScFv fragment in the area of the cerebellum. In vivo biodistribution of 125I-TU-20, 125I-scFv TU-20, 123I-scFv TU-20 and Na125I was proceeded in normal mice (wild type C57B/6/J). Both biomolecules labeled by 123I were also proved in an imaging biodistribution study with use of the SPECT camera. Finally, a transgene population G93A1 Gur was used for comparative study to show the different behaviour of the substances in a normal mouse and in the modified organism with amyotrophic lateral sclerosis. The most part of differences is observed in the area of the muscles, rostal and caudal spinal cord. In summary, the monoclonal antibody TU-20 and its scFv were successfully radioiodinated and afterwards analysed by several quality control methods and biodistribution studies which confirmed their preserved or expected immunoanalytical characteristics in normal and genetically modified organism.  相似文献   

8.
A sulfur compound, bis(4-hydroxybenzyl)sulfide (1) was isolated from the root extract of Pleuropterus ciliinervis. Its structure was elucidated using NMR spectroscopic techniques and mass spectrometric analysis. Compound 1 showed potent inhibitory activity in a histone deacetylase (HDAC) enzyme assay. It also exhibited growth inhibitory activity on five human tumor cell lines and more sensitive inhibitory activity on the MDA-MB-231 breast tumor cell line.  相似文献   

9.
Abstract

This study emphasizes on the investigation of antiplasmodial activity of triterpenoids isolated from Ficus benjamina leaves. An unsaponified fraction of petroleum ether extract of plant leaves was subjected to silica gel column chromatography which led to the isolation of two known triterpenoids; namely ursolic acid and lupeol. These compounds were evaluated for antiplasmodial activity by schizont maturation inhibition assay using 3D7 Plasmodium strains. Both, ursolic acid and lupeol were found to exhibit significant antiplasmodial effect with an IC50 value of 18?µg/ml and 3.8?µg/ml, respectively. This study further confirms the traditional role of Ficus benjamina plant in the treatment of malaria which may be attributed to ursolic acid and lupeol.  相似文献   

10.
Aqueous infusions of the leaves of the shrub Albertisia delagoensis (Menispermaceae) are used in South Africa in traditional Zulu medicine to alleviate a variety of symptoms, including fever, and intestinal problems. We report the analysis of such an aqueous extract using the HPLC-NMR technique. A number of polar compounds were identified, including proto-quercitol, nicotinic acid, allantoic acid, 3,4-dihydroxy-benzoic acid, phthalic acid and the aporphine alkaloid derivative roemrefidine. Allantoic acid and roemrefidine have been fully characterised by (1)H- and (13)C-NMR and mass spectrometry. Earlier reports of antiplasmodial activity of roemrefidine and of A. delagoensis extracts are correlated with this study and with the antipyretic properties of neutral aqueous extracts.  相似文献   

11.
This study was designed to investigate the antimicrobial activity of Cinnamomum iners standardized leave methanolic extract (CSLE), its fractions and isolated compounds. CSLE and fractions were subjected to disc diffusion, minimum inhibitory concentration (MIC) and minimum bactericidal concentration (MBC) tests using different Gram positive and Gram negative bacteria and yeast. Within the series of fractions tested, the ethyl acetate fraction was the most active, particularly against methicillin resistant Staphylococcus aureus (MRSA) and Escherichia coli, with MIC values of 100 and 200 μg/mL, respectively. The active compound in this fraction was isolated and identified as xanthorrhizol [5-(1, 5-dimethyl-4-hexenyl)-2-methylphenol] by various spectroscopic techniques. The overall results of this study provide evidence that Cinnamomum iners leaves extract as well as the isolated compound xanthorrhizol exhibit antimicrobial activity for both Gram negative and Gram positive pathogens, especially against MRSA strains.  相似文献   

12.
NBNPQD (2-benzyl-1-oxo-1,2-dihydropyrido[4,3-b]quinoxaline 5,10-dioxide) is a new synthesized quinoxaline derivative. It could be labeled with auger emitter 125I successfully with yield about 90 %. The labeled product was evaluated by electrophoresis and thin layer chromatography. Factors affected labeling yield were studied. 125I-NBNPQD was stable up to 48 h post labeling. Biodistribution study of 125I-NBPQD in normal and tumor bearing mice was also conducted. The biodistribution data revealed that 125I-NBNPQD diffused rapidly to tumor sites in both ascites and solid tumor bearing mice. 125I-NBNPQD was declined rapidly from most of organs but slowly from tumor sites. In vitro radiotoxicity of 125I-NBNPQD increased with the increase of its radioactivity. This study encourages the possible use of 125I-NBNPQD in tumor imaging and treatment. It also encourages further studies on the chemotherapeutic activity of NBNPQD hoping to get a new potent antitumor agent.  相似文献   

13.
Antifungal bioassay-guided fractionation of Combretum nelsonii leaf extracts afforded two closely related triterpenes, asiatic acid and arjunolic acid. Antifungal activities of the mixture of asiatic acid and arjunolic acid were determined against five fungal animal pathogens. The minimum inhibitory concentrations of the mixture to the different pathogens varied from 0.2 to 1.6 microg mL(-1); Candida albicans (0.9 microg mL(-1)), Cryptococcus neoformans (0.4 microg mL(-1)), Aspergillus fumigatus (1.6 microg mL(-1)), Microsporum canis (0.2 microg mL(-1)) and Sporothrix schenckii (0.2 microg mL(-1)). Microsporum canis and S. schenckii were the most susceptible followed by C. neoformans. Aspergillus fumigatus was the most resistant. The R(f) value of the mixture of asiatic acid and arjunolic acid was 0.27 in CEF (chloroform : ethylacetate : formic acid), 0.09 (BEA; benzene : ethanol : ammonium hydroxide) and 0.55 (EMW; ethylacetate : methanol : water) which was active against all pathogens. In vitro cytotoxicity of mixture gave an LC(50) of 10.58 microg mL(-1) towards Vero monkey kidney cells.  相似文献   

14.
Broccolini (Brassica oleracea Italica?×?Alboglabra) is a hybrid of broccoli and kai-lan, Chinese broccoli. To date, no study has been reported on the chemical composition of the volatile fractions of this raw material. In this study, the volatile constituents from the ethanolic extract of broccolini leaves were analysed by gas chromatography-mass spectrometry (GC-MS). Sixteen compounds were identified. The major components include 5-phenyl-undecane (11%), n-hexadecanoic acid (9.34%), octadecanoic acid (6.39%), 1,1,3-trimethyl-3-phenyl-indan (4.0%), 3-(2-phenylethyl)benzonitrile (3.48%) and phytol (3.37%).  相似文献   

15.
Sea sand disruption method (SSDM) and matrix solid phase disruption (MSPD) were compared to solid-liquid extraction (SLE) for extraction of phenolic compounds from the Ficus carica leaves. Statistical treatment, ANOVA-single factor, was used to compare the extraction yields obtained by these methods, and for the majority of the extracted compounds, significantly higher yields were obtained by the solid disruption methods. Both solid disruption methods are faster and ecologically friendly, but the sea sand method was more reproducible (RSD < 5% for most compounds), and was also the least expensive method. Recoveries above 85% were obtained for chlorogenic acid, rutin, and psoralen using the sea sand extraction method.  相似文献   

16.
Summary Insulin receptors are overexpressed on a number of human tumors, leading to significant affinity of insulin to these tumors. It is appealing to receptor-targeted radiotherapy for malignant tumors if insulin is labeled with suitable radionuclide. In this paper, N-succinimidyl 5-(tributylstannyl)-3-pyridinecarboxylate (SPC), a potential bi-functional linker for radioiodination of proteins or peptides, was synthesizedby using 5-bromonicotinic acid as the starting material. Then, with this bi-functional linker, insulin was conjugated with 131I, and the tissue distribution of the labeled insulin (131I-SIPC-insulin) in normal mice was investigated. The results showed that insulin </span> could be conjugated with131I using SPC as the linker </span> in a labeling yield of40-58%, and with radiochemical purity of more than 98% after purification bySephadex?G-10. Even kept at room temperature for 72 hours, the radiochemical purity of 131I-SIPC-insulin was still more than 97%, implying that the conjugated insulin was constantly stable in vitro.Meanwhile, in order to evaluate the in vivo stability of the conjugated compounds, insulin was also labeled with 131I by a direct method using chloramine-T (Ch-T) as the electrophilic agents.Biodistribution of131I-SIPC-insulinin micesuggested that 131I could clear rapidly from the blood,mainly excreted by kidney. However, 131I uptake of mice with131I-SIPC-insulin in some key organs, especially in thyroid and stomach, were much less (150 or 30 times) than that with the direct labeled insulin (131I-insulin). Additionally, it was noted that 131I-SIPC-insulin hasmuch betterinvivo stability than131I-insulin.</p> </p>  相似文献   

17.
A cytotoxic compound from the leaves of Juglans mandshurica   总被引:1,自引:0,他引:1  
From Juglans mandshurica leaves, a new quinone compound was isolated through bioassay-guided fractionation. The structure elucidation of the compound was established based on spectroscopic studies, notably of the 2D NMR spectra. The compound exhibited moderate cytotoxic activities against Hela, MCF-7, BGC823 and 3T3-Llcell lines with IC50 ranges from 7.5 to 26.8 μmol/L.  相似文献   

18.
银杏叶提取物中黄酮类化合物的分光光度分析研究   总被引:7,自引:0,他引:7  
建立了一种银杏叶提取物中黄酮类化合物的分光光度测定方法。研究表明在NaNO2存在下,pH在13.20~13.60范围内,银杏叶提取物与Al(NO3)3形成稳定的粉红色配合物,于λmax=510nm处进行分光光度分析。标准品选用芦丁,其标准曲线在4.606~55.27μg/mL范围内服从朗伯-比尔定律,相关系数为r=0.9998。回收率为98.58%~102.80%,RSD为0.111%。可用于银杏叶提取物中黄酮类化合物的测定。  相似文献   

19.
In this paper water-soluble fullerene derivative C60(OH)xOy was radioiodinated with the iodogen method. The labeling yield was determined by radio-TLC. The effects of pH value, reaction time, temperature and amount of the iodogen on the labeling yield were studied. The labeled product was purified by Sephadex G-25 column chromatography and then the stability of 125I-C60(OH)xOy was examined . The results showed that the radiochemical purity of 125I-C60(OH)xOy solution with benzylalcohol remained 82.7% after 43 hours.  相似文献   

20.
Several triorganotin(IV) compounds and Terrazole® 35 WP were screened for their in vitro antifungal activity against three isolates of Phytophthora palmivora. Two isolates (isolates Phy. 2 and Phy. 334) were obtained from black pepper (Piper nigrum L.) and one isolate (isolate Phy. 56) from cocoa leaves (Cacao theobromae). ED50 values for radial growth of the isolates ranged from 0.09 to 1,700 μg cm?3 for the triorganotin(IV) compounds and from 3.46 to 1 227 000 μg cm?3 for Terrazole®. Diphenylbutyltin bromide exhibited the highest antifungal activity against the three isolates of P. palmivora with ED50 values ranging from 0.30 to 0.73 μg cm?3. Diphenylbutyltin bromide was equally effective against a freshly isolated virulent culture of P. palmivora (isolate Phy. 346) from black pepper leaves in Sarawak, East Malaysia, yielding an ED50 value for radial growth of 0.87 μg cm?3 and a probit-log concentration regression line slope value of 1.04. In vitro efficacy of diphenylbutyltin bromide against isolate Phy. 346 using detached healthy pepper leaves showed 40–75% infection of leaves at 100 μg cm?3 and no infection at 500 μg cm?3. Diphenylbutyltin bromide at 100 μg cm?3, however, inhibited the diameter of lesion by 43.3–73.7% compared with the untreated controls. Black pepper leaves treated with Terrazole® at 778 μg cm?3 exhibited 5.3–33.3% inhibition of lesion diameter compared with the untreated controls, where 90–100% of the leaves were infected. Concentrations of diphenylbutyltin bromide of 1000–2500 μg cm?3 caused some injury lesions on the leaves. From the results obtained, it appears that diphenylbutyltin bromide could be used as a protective spray or drench against P. palmivora infection of black pepper at 100–500 μg cm?3.  相似文献   

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