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1.
Four compounds with similar structures and UV spectra were isolated from the fermentation broth of Armillaria mellea by means of preparative HPLC. Their structures were established as methyl (2S)‐1‐[2‐(furan‐2‐yl)‐2‐oxoethyl]‐5‐oxopyrrolidine‐2‐carboxylate ( 1 ), (2S)‐1‐[2‐(furan‐2‐yl)‐2‐oxoethyl]‐5‐oxopyrrolidine‐2‐carboxylic acid ( 2 ), 1‐[2‐(furan‐2‐yl)‐2‐oxoethyl]pyrrolidin‐2‐one ( 3 ) and 1‐[2‐(furan‐2‐yl)‐2‐oxoethyl]piperidin‐2‐one ( 4 ) on the basis of their 1D‐ and 2D‐NMR, and HR‐MS data. The absolute configurations of compounds 1 and 2 were determined by comparison of the experimental and calculated electronic circular dichroism (ECD) data. Additionally, four known compounds, 5 – 8 , were also isolated.  相似文献   

2.
Experimental1FungusMaterialThefungusmaterial,naturalbodiesofArmilariamelea,werecolectedfromtheDaxinganMountainregion.2Instrum...  相似文献   

3.
4.
单扫描示波极谱法连测五味子、榛蘑中的铜和锌   总被引:1,自引:0,他引:1  
研究了在HCl-KSCN底液中用单扫描示波极谱法连续测定五味子、榛蘑中铜和锌的方法。在此底液中,铜、锌分别在-0.42V(vs.SCE)、-1.03V(vs.SCE)处产生一敏锐的二阶导数波,检出限分别为0.005、0.01μg/mL,线性范围分别为0.01~8.00μg/mL,0.01~10.00μg/mL。应用本方法测定了五味子、榛蘑中的铜和锌,方法回收率为96.5%~101.8%。  相似文献   

5.
Swertia chirayita is one of the potential medicinal plants of the family Gentianaceae in traditional medicine. Due to its high demand and scarcity, trade of chirayita is affected by adulterants. Swertia species from Western Ghats were compared with S. chirayita for phytochemical characterisation and antioxidant activities by using different extracts. This study revealed that acetone is the best extraction solvent of phenolic and flavonoid compounds with antioxidant properties as compared with other extracts. S. chirayita showed better antioxidant activity than other species with highest content of phenolics and flavonoids. Among the species from Western Ghats, Swertia minor has better antioxidant properties with higher content of phenolics and flavonoids when compared with S. chirayita. Gallic acid was detected in all species under study by using HPLC analysis. The Swertia species under study showed similar phytochemical properties and antioxidant potential and hence their use as substitute to S. chirayita needs to be further investigated.  相似文献   

6.
Gamma-aminobutyric acid (GABA) is the major inhibitory neurotransmitter in the central nervous system of mammals and plays an important role in the suppression of neurons’ excitability. GABA is formed from the decarboxylation of glutamic acid (Glu), and both GABA and Glu could be considered as important biologically active food components. In the current study, we validated a HPLC method for concomitant detection of GABA and Glu in plant samples after derivatization with dansyl chloride. The validated method had high precision and a high recovery rate and was successfully used for GABA and Glu quantification in 55 plant foods (fruits, vegetables, legumes, cereals, pseudocereals, and nuts) and 19 medicinal plants. Vegetables were the most important dietary source of these amino acids, with the highest quantity of GABA found in potatoes—44.86 mg/100 g fresh weight (FW) and yellow cherry tomatoes—36.82 mg/100 g FW. The highest amount of Glu (53.58 mg/100 g FW) was found in red cherry tomatoes. Analyzed fruits were relatively poor in GABA and Glu, and European gooseberry was the richest fruit with 13.18 mg/100 g FW GABA and 10.95 mg/100 g FW Glu. Cereals, pseudocereals, nuts, and legumes contain much higher amounts of Glu than GABA. The obtained results enrich the available information on the content of gamma-aminobutyric and glutamic acids in plant foods and could be used for the development of GABA-enriched functional foods.  相似文献   

7.
Multiplex environmental factors are generally expected to have significant effects on genetic diversity of plant populations.In this study,randomly amplified polymorphic DNA(RAPD) technique was used to reveal the genetic diversity in the same species of four populations collected from Niupidujuan(Rhododendron chrysanthum) at different altitudes,an endangered species,endemic to Northeast China.Initially,twenty informative and reproducible primers were chosen for final RAPD analysis.A total of 152 clear bands...  相似文献   

8.
十三种利尿剂的高效液相色谱测定方法   总被引:5,自引:0,他引:5  
对近几年国际奥委会医学委员会公布的禁用表中新增药物及一系列利尿剂的相关化合物进行了研究,比较了不同的提取方法及回收率,研究了几种药物的排泄情况;建立了同时分析13种利尿剂的高效液相色谱测定方法,检出限小于5ng。  相似文献   

9.
茶中茶多酚的高效液相色谱法分离分析   总被引:18,自引:3,他引:18  
用改进的Agarwal方法萃取不同种类茶叶和茶饮料中的茶多酚,建立了用高效液相色谱(HPLC)法对茶多酚进行分离分析方法。HPLC可有效分离GTPs主要组成成分EC、EGC、ECG和EGCG并精确定量,相对标准偏差小于5%。茶叶加工过程对GTPs含量有很大影响,绿茶总GTPs含量在6 ̄15g/100g干茶叶、乌龙茶总GTPs含量在5 ̄7g/100g干茶叶,红茶总GTPs含量低于2g/100g干茶叶  相似文献   

10.
Efficient plantlet regeneration with and without intermediate callus phase was achieved for a selected genotype of Aloe vera L. which is sweet in test and used as a vegetable and source of food. Random amplified polymorphic DNA (RAPD) and inter simple sequence repeats (ISSR) marker assays were employed to evaluate genetic stability of plantlets and validate the most reliable method for true-to-type propagation of sweet aloe, among two regeneration systems developed so far. Despite phenotypic similarities in plantlets produced through both regeneration systems, the differences in genomic constituents of plantlets produced through intermediate callus phase using soft base of inflorescence have been effectively distinguished by RAPD and ISSR markers. No polymorphism was observed in regenerants produced following direct regeneration of axillary buds, whereas 80% and 73.3% of polymorphism were observed in RAPD and ISSR, respectively, in the regenerants produced indirectly from base of the inflorescence axis via an intermediate callus phase. Overall, 86.6% of variations were observed in the plantlets produced via an intermediate callus phase. The occurrence of genetic polymorphism is associated with choice of explants and method used for plantlet regeneration. This confirms that clonal propagation of sweet aloe using axillary shoot buds can be used for commercial exploitation of the selected genotype where a high degree of fidelity is an essential prerequisite. On the other hand, a high degree of variations were observed in plantlets obtained through indirect regeneration and thus cannot be used for the mass multiplication of the genotype; however, it can be used for crop improvement through induction of somaclonal variations and genetic manipulations.  相似文献   

11.
《Analytical letters》2012,45(7):1125-1131
Abstract

A simple and sensitive method has been developed for the determination of disopyramide employing reverse phase high performance liquid chromatography with UV detection. p-Chlorodisopyramide was used as an internal standard. The retention times of disopyramide and the internal standard at an elution rate of 1.8 ml/min were 6.28 and 8.78 min, respectively.  相似文献   

12.
采用Hypersil硅胶柱,在流动相为正己烷-四氢呋喃(体积比90:10),流速为1.0mL/min,检测波长为230nm,柱温为20℃时,速霸螨中克螨特和唑螨酯得到很好分离;克螨特的平均回收率为100%,标准偏差为0.65g/L,相对标准偏差为0.66%;唑螨酯的平均回收率为98%,标准偏差为0.08g/L,相对标准偏差为0.29%;方法简便、快捷、准确。  相似文献   

13.
50%多菌灵·福美双可湿性粉剂高效液相色谱分析   总被引:2,自引:0,他引:2  
采用反相高效液相色谱法,使用BDS-C18柱和紫外检测器,以V(甲醇)∶V(乙酸钠)=1∶2缓冲溶液(pH=4.7)为流动相,在281 nm波长处,同柱测定多菌灵和福美双,此方法的标准偏差分别为0.0871和0.0697;RSD分别为0.35%和0.28%;线性相关系数分别为0.9991和0.9991;平均回收率分别为99.96%和99.87%。  相似文献   

14.
烷基苯磺酸盐型表面活性剂的HPLC及HPCE分离分析进展*   总被引:3,自引:0,他引:3  
作为一种常见的表面活性剂,烷基苯碘酸盐(ABS)被广泛用于许多领域。本文结合作者最近的研究结果,对烷基苯磺酸盐表面活性剂的HPLC及HPCE分离分析现状及其应用前景进行了综述。  相似文献   

15.
采用Hypersil硅胶柱在合适的条件下使阿锐克乳油中的氯氰菊酯的4个异构体较好分离,通过对外标法和内标法的比较,建立了氯氰菊酯快速、准确的高效液相色谱定量分析方法,该法的回收率为99.9%~101.4%;标准偏差为0.001;相对标准偏差为1.76%。  相似文献   

16.
《Analytical letters》2012,45(7):1177-1188
Abstract

A simple, rapid and precise high-performance liquid chromatographic assay of meclizine in tablets has been developed. Reversed-phase chromatography was conducted using a mobile phase of acetonitrile and water (30% V/V) and detection at 230 nm. The recovery and coefficient of variation from six placebo tablets containing 25 mg of meclizine were 100.5% and 0.84%, respectively. Replicate regression analyses of three standard plots in the concentration range of 1–12 mcg/ml obtained on three different days gave a correlation coefficient >0.998 and the coefficient of variation of the slopes <1%. The assay was precise within day and between days as indicated by ANOVA test. The recoveries from 10 replicate tablets of the two different commercial meclizine brands were 98.5 and 100.7% of the label amount and their coefficients of variation were 1.16 and 1.71%.  相似文献   

17.
Cydonia oblonga is a medicinal plant that is used to treat a number of health complications in traditional medication systems. The objective of this study was to evaluate the phytochemical composition, and antibacterial, antioxidant, and ant-diabetic potentials of methanolic extracts of Cydonia oblonga bark. The Cydonia oblonga bark extraction was fractionated through HPLC and seven purified fractions labeled as F1, F2, F3, F4, F5, F6, and F7 were obtained. The HPLC-UV analysis of methanolic extract showed the presence of a number of possible compounds. The GC-MS and HPLC analysis confirmed the presence of the following bioactive compounds in the crude extract and purified fractions: malic acid, mandelic acid, quercetin, caffeic acid, catechin hydrate, as morin (HPLC analysis), BIS-(2-ethylhexyl)phthalate and diisooctyl phthalate (F1), carbamide (F2, used as fertilizer), octasiloxane and dimethylsiloxanecyclictrimer (F3), silicic acid and cyclotrisiloxane (F4), 6-AH-cAMP, 4H-cyclopropa[5′,6′]benz[1′,2′,7,8]azule, and 4-(4-chlorophenyl)-3-morpholinepyrol-2-yl)-butenedioic acid (F5), isopropyamine (F6), and 1-propylhydrazine (F7). The extract and purified fractions were then tested for biological activities. All the purified fractions and methanolic extract showed effective antibacterial activity; however, the highest activity was recorded for methanolic extract against Staphylococcus aureus and Streptococcus pneumonia. Antioxidant evaluation of methanolic extract and purified fractions against DPPH showed strong % inhibition of the synthetic free radical. The methanolic extract exhibited 87.41 ± 0.54% inhibition whereas fractions showed: F1, 85.45 ± 0.85; F2, 65.78 ± 0.68; F3, 58.61 ± 0.58; F4, 80.76 ± 0.59; F5, 571.29 ± 0.49; F6, 85.28 ± 0.94; and F7, 48.45 ± 0.62% inhibition. Ascorbic acid (standard) was used as a control with 94.88 ± 0.56% inhibition at a maximum concentration of 1000 µg/mL. The α-glucosidase inhibition assay of methanolic extract and purified fractions at a maximum concentration of 1000 µg/mL showed activities as: methanolic extract, 78.21 ± 0.67; F1, 55.01 ± 0.29; F2, 56.10 ± 0.24; F3, 62.44 ± 1.03; F4, 70.52 ± 0.15; F5, 62.18 ± 0.92; F6, 72.68 ± 0.2; and F7, 57.33 ± 0.05% inhibition. α-Amylase % inhibition of methanolic extract and purified fractions were noted as: methanolic extract, 77.98 ± 0.57; F1, 79.72 ± 0.02; F2, 79.72 ± 0.02; F3, 82.16 ± 0.48; F4, 77.37 ± 0.28; F5, 72.14 ± 0.30; F6, 74.24 ± 0.29; and F7, 56.58 ± 0.10 at the highest concentration of 1000 µg/mL. Acarbose (standard) showed 87.65 ± 0.71% inhibition of α-glucosidase and 85.99 ± 0.44% inhibition of α-amylase at the highest concentration of 1000 µg/mL. It was found that all biological activities of methanolic extract and purified fractions might be attributed to the fact that they are rich sources of phenolic and flavonoids along with other bioactive compounds. The total phenolic and flavonoid contents of methanolic extract were recorded higher as compared to purified fractions (TPC = 70% and TFC = 69%). Amongst the purified fractions, fraction 6 exhibited the highest TPC value (64%), and purified fraction 1 exhibited the highest value of TFC (58%). Recent research demonstrated that Cydonia oblonga may be considered an antibacterial medicinal plant. The result of the present study revealed that it might be utilized for the isolation of bioactive phytochemicals that can lead to new opportunities in the discovery of new antibiotics.  相似文献   

18.
蒸发光散射检测器HPLC法测定大豆低聚糖;HPLC;ELS检测器;梯度洗脱;低聚糖;大豆  相似文献   

19.
建立了一种能同时快速分离、定性番茄中3种类胡萝卜素及其异构体的高效液相色谱(HPLC)方法。采用正己烷-乙醇(3∶4)对样品进行提取,甲基叔丁基醚+0.05%三乙胺-乙腈+0.05%三乙胺为流动相梯度洗脱,以Carotenoid C30柱(250 mm×4.6 mm i.d.,5μm)进行分离,检测波长为475 nm。结果表明,在优化实验条件下,番茄中有11种类胡萝卜素得到了良好分离,包括3种全反式异构体和8种顺式异构体。叶黄素、β-胡萝卜素、番茄红素分别在0.1~5.0,0.1~20,0.1~100μg/m L浓度范围内线性关系良好,相关系数均在0.99以上,检出限(LOD)分别为0.13,0.12,0.56μg/g,定量下限(LOQ)分别为0.43,0.41,1.88μg/g;日内相对标准偏差(RSD)为1.2%~5.3%,日间RSD为1.9%~7.5%,回收率分别为(88.9±6.1)%~(91.7±3.6)%,(92.3±4.3)%~(94.1±6.3)%,(102.6±4.2)%~(107.1±3.4)%。该方法具有分析时间短、灵敏度高、分离完全等优点,适用于番茄中类胡萝卜素及其顺式异构体的分析测定。  相似文献   

20.
A method for the determination of methylamine (MA) in aqueous matrices is reported which uses solid-phase microextraction (SPME) for enrichment and derivatization of the analyte, and high performance liquid chromatography (HPLC). The fluorogenic reagent 9-fluorenylmethyl chloroformate (FMOC) has been used for derivatization. The SPME fibres were successively immersed in the samples and in the derivatization solutions to extract MA and FMOC, respectively. After a defined time of reaction, the derivatized analyte was desorbed into the chromatographic system, and chromatographed in a LiChrosphere 100 RP18, i.d., 5 μm, column under gradient elution. In order to improve the MA-FMOC peak profile, a precolumn ( i.d., packed with Hypersil C18 phase, 30 μm) was connected on-line to the analytical column by means of a switching valve. The experimental conditions (including fibre coating, times of adsorption, reaction and desorption, and concentration of reagent) have been optimised, and the results have been compared with those achieved by using a method previously validated for aliphatic amines in which extraction and derivatization were carried into C18 solid-phase extraction (SPE) cartridges. Although less sensitive, the SPME based method allowed the quantification of MA over the range 2.5-10.0 μg/ml with linearity, reproducibility and accuracy comparable to that of the SPE based method, the limit of detection being 0.75 μg/ml. The main advantages of the proposed SPME procedure are: sample handling involved in the extraction and derivatization steps was considerably reduced, it was free organic solvent and non-destructive. Moreover, the proposed conditions allowed the selective determination of MA in the presence of other primary and secondary short-chain aliphatic amines. The utility of the proposed procedure for the quantification of MA in different types of waters is discussed.  相似文献   

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