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 14 毫秒
1.
A simple, reliable and rapid reversed-phase HPLC-PAD procedure for the characterisation and quantitative determination of the anti-diabetic sesquiterpene lactone enhydrin (1) from Smallanthus sonchifolius (yacón) has been evaluated and validated. The approach focused on the analysis of various leaf rinse extracts, as well as the glandular trichomes of intact leaves, in which 1 was the major compound detected. The best sample preparation of a rinse extract yielded 0.67 mg/mL of 1, whilst a rapid rinse of a small piece of one dried leaf gave 0.09 mg/mL of 1; the highest concentration obtained from a glandular extract was 0.07 mg/mL. The dried leaves of S. sonchifolius were found to contain a total of 0.97% of 1.  相似文献   

2.
王四海  孙卫邦  成晓  杨宇明 《生态学报》2008,28(3):1307-1313
肿柄菊 Tithonia diversifolia (Hemsl.) A.Gray 原产墨西哥及中美洲,被作为观赏及绿肥植物引入我国各地栽培.引入云南栽培的肿柄菊于20世纪30年代在云南南部逃逸生长,现在云南的热带、南亚热带和中亚热带地区形成危害.为了查明肿柄菊的扩散特点和入侵潜能,对选取的5个不同地理气候条件下的肿柄菊居群的果序直径、每序结实量、结籽率、千粒重、种子大小(长和宽)等6个指标进行统计分析.结果表明,6个生物学指标在5个居群间都具有极显著差异(p<0.01),并随着居群间地理气候条件差异的增大,这6个指标值在居群间的差异也有增大趋势.对新鲜采集的不同居群种子在15、20、25、30、35℃下做萌发实验,结果显示在前4种温度条件下5个居群间的种子萌发率有极显著差异(p<0.01),在35℃下萌发率有显著差异(p<0.05),并且5个居群的种子最高萌发率不相同且差异极显著(p<0.01).分析对比作者以往对肿柄菊群落特征和克隆繁殖特性的研究结果认为,虽然肿柄菊在不同的地理气候条件下有性繁殖特性有较大差异,但群落结构差异不大,危害程度表现相似;由于肿柄菊有性繁殖和克隆繁殖的协同作用,使其通过人为引种、道路交通、水流等传播到新的地域后,极易建立新种群,并形成单优种群落而不断侵占和统治新的领地.  相似文献   

3.
王四海  孙卫邦  成晓 《生态学报》2004,24(3):444-449
调查表明 ,肿柄菊在云南省已逃逸生长于北纬 2 4°10′以南的 53个县区 ,面积达 184,2 12 km2。分布区为热带、南亚热带、中亚热带气候类型。逃逸生长的肿柄菊呈多年生灌木或亚灌木状 ,植株全年生长 ,5~ 10月份的雨季是其生长旺盛期 ,10月份开始献蕾 ,花期为 11月至翌年 1月份 ,果熟期 12月下旬至翌年 2月份。肿柄菊的结实量高达 80 0 0 0~ 160 0 0 0枚 / m2 ,种子 (瘦果 )千粒重 4.5782~ 6.52 92 g。成熟种子在风力摇曳下从果序中脱出 ,借助风力、流水或附着于交通工具、人畜等广泛散播 ,在适宜的生境下实现萌发生长和种群扩增。肿柄菊能依靠植株基部节处萌生的小芽体形成克隆分株 ,克隆分株迅速生长后成密集状丛生 ,在倒伏或贴地面生长的茎秆上萌生无数的不定根和不定芽 ,进一步实现植物体的克隆增殖。由于肿柄菊强大种子繁殖潜力、特殊的克隆增殖特性和植物体固有的化感作用 ,种群个体在适宜的环境条件下快速扩增 ,排挤本土植物 ,形成大面积的单一优势种群落 ,其伴生植物多为一些适应范围广的 1年、2年生或多年生杂草。肿柄菊的多种特征表明它是一种具有较大潜在危害性的外来植物  相似文献   

4.
Introduction – Artemisia annua is a rich source of biologically active substances such as terpenoids, coumarins and polyacetylenes. These chemicals have been reported to show beneficial pharmacological properties such as antitumor and antibacterial activities. In genetically transformed root cultures of A. annua, three bioactive metabolites, namely, ponticaepoxide (an insecticidal polyacetylene, 1 ), drimartol A (an anticancer sesquiterpene coumarin, 2 ) and (Z)‐7‐acetoxy‐methyl‐11‐methyl‐3‐methylene‐dodeca‐1,6,10‐triene (a new anticancer sesquiterpene, 3 ) were isolated and identified in our recent work. However, no quantitative analysis methods for any of them are yet available, nor for their simultaneous analysis. Objective – To develop an HPLC‐PAD method for simultaneous determination of 1 , 2 and 3 in hairy root cultures of A. annua. Methodology – HPLC operating conditions were optimised and the chromatographic separation was performed on a C18 column with a gradient acetonitrile : water as mobile phase. Results – Linear relationships within the range of investigated concentrations were observed for the three metabolites with their correlation coefficients greater than 0.997. The method was validated for repeatability (RSD <3.59%) and intra‐ and inter‐day precision (RSD <3.1%) with recovery between 94.8 and 107.6% and the RSD less than 3.40%. The method was successfully applied to the time‐course of accumulation of the bioactive compounds in genetically transformed root cultures of A. annua. Conclusion – The HPLC‐PAD method developed for the simultaneous determination of three bioactive metabolites 1 , 2 and 3 was simple, reproducible and sensitive. Copyright © 2010 John Wiley & Sons, Ltd.  相似文献   

5.
A simple and rapid isocratic reversed-phase high-performance liquid chromatographic method for the quantification of alantolactone/isoalantolactone and three thymol derivatives in roots and root cultures of Inula helenium and I. royleana has been developed. The method could be applied to screen raw materials in search for highly productive plants and in vitro cultures.  相似文献   

6.
Ceramides play an important role in diverse cellular functions such as differentiation, cell cycle progression, cell-cell adhesion, senescence, and apoptosis. Here we report a method of extracting lipids from mammalian cells and quantifying ceramide, where the assay conditions were optimized for reproducibility, linearity, recovery, and sensitivity. Simultaneous chromatographic separations were carried out by reversed-phase high-performance liquid chromatography coupled to electrospray ionization using a Pursuit 3 Diphenyl column (50 × 2.0 mm) and supported by a mobile phase consisting of acetonitrile plus 0.1% formic acid and 25 mM ammonium acetate. Ceramides were detected in the multiple reaction mode by tandem mass spectrometry in the positive ion mode, and all extracted ion peaks were integrated for quantitative analysis. The limits of detection and quantification achieved were 0.2 and 1.0 pg on column, respectively. Using this method, we successfully quantified and compared differences in C18 ceramide levels induced by two DNA-damaging agents, mitomycin C and daunorubicin, and two apoptosis-inducing ligands, tumor necrosis factor alpha (TNF-α) and TNF-related apoptosis-inducing ligand (TRAIL). This work, therefore, describes a method that will be helpful for investigating how ceramide is regulated by different chemotherapeutic agents and will help us to better understand the mechanisms of signal transduction involving ceramide.  相似文献   

7.
Contamination of soils by effluents from industries is on the increase. There is the possibility of remediating these contaminated soils through the use of certain plants. This work investigated the remediating ability of Helianthus annuus and Tithonia diversifolia on the soil polluted with effluents from a paint industry in Ibadan, Nigeria. The experiment consisted of three treatments (H. annuus, T. diversifolia, and control) each replicated three times in a factorial combination of four different fertility managements, viz mineral fertilizer (MF); Grade A organomineral fertilizer (OMF); control1, plants without fertilizer application; and control2, where no fertilizer and no crop was planted using randomized complete block design. A total of 12 plots of 2 × 4 m2 each per phytoplant were obtained. Each plot was planted with the viable seeds of the phytoplant at a spacing of 60 × 30 cm2 and at the seed rate of four seeds per hole. The seedlings were thinned to two stands per hole 2 weeks after planting (WAP) and also weeded two times (2 and 5 WAP). After in situ second successive cultivation, percentage removal of heavy metals by Helianthus annuus with MF and OMF, respectively, were Cu 32.5 and 41.6; Pb 30.3 and 42.8; and Cd 44.5 and 56.7. Tithonia diversifolia, similarly, removed, respectively, Cu 16.9 and 23.4; Pb 36.9 and 43.7; and Cd 20.1 and 35.1. Lower percentages were removed in the controls where no fertilizer was applied. In the shoot of H. annuus with OMF, significantly (p< .05) higher values of 0.27, 1.72, and 0.11 mg kg?1 of Cu, Pb, and Cd, respectively, were removed and stored at second cultivation as against 0.21, 3.39 and 0.08 mg kg?1 in the shoot of T diversifolia. Lower values of Cu, Pb, and Cd were removed with MF, and also at first cultivation with OMF and MF. This study therefore recommends the use of sunflower plants, whether hybrids or wild-types along with the application of OMF for the effective remediation of soils contaminated with heavy metals, particularly in tropical climate.  相似文献   

8.
Introduction – Naphthoquinones; lawsone ( 1 ), lawsone methyl ether ( 2 ) and methylene‐3,3′‐bilawsone ( 3 ) are the main active compounds of Impatiens balsamina leaves. Objective – To develop and validate an HPLC method for simultaneous quantitative determination of 1 – 3 in I. balsamina leaf extracts. Methodology – The method utilised a Supelco® C18 column (5 µm, 4.6 × 150 mm) at 25°C with the mixture of 2% aqueous acetic acid : methanol (gradient elution as follows: 0–10 min, 25 : 75; 10–20 min, 32 : 68; 20–35 min, 55 : 45) as the mobile phase at a flow‐rate of 1 mL/min, and UV detection at 280 nm. The parameters of linearity, repeatability, reproducibility, accuracy specificity and sensitivity of the method were evaluated. Results – The recovery of the method was 96–101% and linearity (r2 ≥ 0.9995) was obtained for all naphthoquinones. A high degree of specificity, as well as repeatability and reproducibility (RSD less than 5%), were also achieved. Copyright © 2010 John Wiley & Sons, Ltd.  相似文献   

9.
The analysis by HPLC, CE and CE-MS/MS of root bark extracts of a, so far undescribed, Central-African Ancistrocladus species (family Ancistrocladaceae) is described. Owing to the complexity of the extract, the application of reversed-phase HPLC resulted in a partially incomplete separation of the naphthylisoquinoline alkaloids, whilst CE using a non-aqueous buffer proved to be a very valuable complementary method for a first characterisation of the crude extract. By performing additional CE-MS/MS experiments, in combination with parallel isolation studies and structural elucidation using conventional methods, six alkaloidal substances present in the plant could be identified.  相似文献   

10.
The imidazoacridinone C1311 has shown anti-tumour activity both in vitro and in vivo, prompting its acceptance for Phase I clinical trials. A high-performance liquid chromatography method using fluorescence detection has been developed for the analysis of C1311 in mouse and human plasma and mouse tissue samples. This method is selective, sensitive (limit of detection of 1 ng ml−1) and reproducible, with recoveries of>90%. C1311 was stable over 8 h, at 25°C, in plasma, tumour homogenate, saline and a range of buffers (pH 3.0–8.0). The compound was highly protein bound (>90%) in plasma which may have important consequences in the pharmacokinetics of the drug.  相似文献   

11.
A rapid and sensitive high-performance liquid chromatography assay method was developed to determine serum fluoxetine and norfluoxetine levels by single extraction of 0.1 ml of serum with sodium hydroxide. The mobile phase (55% acetonitrile–45% distilled water containing 10 mM aqueous triethylamine) was used to separate fluoxetine and norfluoxetine (25–1000 ng/ml, using clomipramine as the internal standard) by ultraviolet detection at 226 nm. The inter- and intra-day variabilities of fluoxetine and norfluoxetine were 13–18%, and the recoveries of both drugs exceeded 89%. This assay method was applied to a pharmacokinetic disposition study of fluoxetine in mice.  相似文献   

12.
We present a validated high-performance liquid chromatography/mass spectrometry (HPLC/MS) method for the quantification of malonyl-coenzyme A (CoA) in tissues. The assay consists of extraction of malonyl-CoA from tissue using 10% trichloroacetic acid, isolation using a reversed-phase solid-phase extraction column, HPLC separation, and detection using electrospray MS. Quantification was performed using an internal standard ([(13)C(3)]malonyl-CoA) and multiple-point standard curves from 50 to 1000pmol. The procedure was validated by performing recovery, accuracy, and precision studies. Recoveries of malonyl-CoA were determined to be 28.8+/-0.9, 48.5+/-1.8, and 44.7+/-4.4% (averages+/-SD, n=5) for liver, heart, and skeletal muscle, respectively. Accuracy was demonstrated by the addition of known amounts of malonyl-CoA to tissue samples. The malonyl-CoA detected was compared with the malonyl-CoA added, and the resulting relationships were linear with slopes and regression coefficients equal to 1. Precision was demonstrated by repetitive analysis of identical samples. These showed a within-run variation between 5 and 11%, and the interbatch repeatability was essentially the same. This procedure was then applied to rat liver, heart, and skeletal muscle, where the malonyl-CoA contents were found to be 1.9+/-0.6, 1.3+/-0.4, and 0.7+/-0.2nmol/g wet weight, respectively, for these tissues. This analytical approach can be extended to the quantification of other acyl-CoA species with no significant modification.  相似文献   

13.
Reverse-phase HPLC with refractive index and light scattering detectors in isocratic and gradient elution modes, respectively, was applied for the separation of the major triacylglycerols (TAG) in coffee lipids. Twelve TAG species could be identified and determined using a linear gradient of acetonitrile in dichloromethane: dichloroethane. The quantitative evaluation was based on the relative area percentages derived directly from a data-station. The procedure was applied to determine the TAG composition of three types of coffee beans harvested in two coffee producing areas in Brazil and dried by two commonly used procedures. No significant differences in the TAG compositions due to the type, origin and drying procedure were found.  相似文献   

14.
15.
16.
17.
18.
A reversed-phase high-performance liquid chromatography (RP-HPLC) method was developed for detection and quantification of free maytansinoid drug in disulfide-linked conjugates between monoclonal antibodies and the maytansinoid drug DM1 (MAb-DM1). Mobile phases and gradient conditions were optimized for separation of several DM1-related free drug species from MAb-DM1 conjugates. The selectivity, linearity, and reproducibility of the method are reported. Reduction of the disulfide-linked DM1 followed by RP-HPLC allowed estimation of purity of MAb-linked DM1 as well as recovery of L-DM1. The method was also used to estimate drug per MAb ratios, which were consistent with those determined by UV spectroscopy.  相似文献   

19.
A rapid method for desalting and concentrating dilute protein solutions using short reversed-phase columns (3-4 cm) has been described. The recovery of proteins is usually 90-100%. The method is simple and rapid and allows the desalting and concentration of protein samples simultaneously. A wide variety of proteins in the range up to 80 kDa can be desalted in microgram to milligram amounts, and volumes up to 1 liter can be concentrated to a few milliliters by a single injection.  相似文献   

20.
Extracts of Tripterygium wilfordii Hook F. have been widely used in China to treat a variety of autoimmune and inflammatory diseases. The diterpenoids triptolide and tripdiolide are two major active components in the T. wilfordii ethyl acetate extract. An efficient solid-phase extraction and high-performance liquid chromatography (SPE-HPLC) method to measure triptolide content in the extract has been previously reported. However, a suitable means of tripdiolide quantification is not available because of interfering compounds in the extract that co-elute with tripdiolide. Therefore, this paper describes a method wherein tripdiolide content can be measured from a small amount of the extract. The extract solution (600 microL) was applied into an aminopropyl SPE tube. Triptolide was eluted with dichloromethane:methanol (1 mL, 49:1 v/v), followed by tripdiolide elution with dichloromethane:methanol (3 mL, 17:3 v/v). The tripdiolide eluate was analysed by HPLC using an isocratic solvent system and was quantified by measuring the peak area at 219 nm. The contents of triptolide and tripdiolide in the extract were determined to be 807.32 +/- 51.94 and 366.13 +/- 17.21 microg/g of extract, respectively. Since tripdiolide is biologically active and makes up a considerable portion of the extract, for extract quality control and standardisation purposes, it should be measured along with triptolide using the proposed SPE-HPLC method.  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