食用牛肝菌不同部位紫外指纹图谱鉴别分析

采用紫外光谱技术结合主成分分析法,建立快速鉴别牛肝菌的不同部位及不同种类、产地的方法。通过单因素实验确定提取牛肝菌特征成分的最佳条件,制备测试液并进行紫外光谱测定。结果表明,牛肝菌样品的重现性、精密度和10h内稳定性的RSD（%）分别在0.09–1.81、0.11–1.92、0.06–2.33之间;牛肝菌不同部位紫外指纹图谱具有明显的指纹特性;主成分分析（PCA）表明菌盖和菌柄前3个主成分累积贡献率分别为94.797%和92.961%,能够反映样品的主要信息;SIMCA软件分析显示牛肝菌菌盖和菌柄化学成分积累不同。根据牛肝菌不同部位紫外光谱信息和主成分分析能区分同一牛肝菌的不同部位,鉴别不同种类、不同产地的食用牛肝菌。     

Optimization of microwave-assisted extraction followed by solid phase micro extraction and gas chromatography-mass spectrometry detection for the assay of some semi volatile organic pollutants in sebum

Methodology using MAE/SPME/GC-MS is being pursued for the analysis of organic pollutants in sebum. The microwave-assisted extraction (MAE) of standards of semi volatile organic pollutants from sebum was optimized. All compounds were extracted from sebum with recoveries analyzed by GC/MS ranging from 94% to 100% under the optimum MAE conditions: 10mL acetone-hexane (2:1), 60 degrees C, and 10 min microwave heating. To improve the detection limits a SPME procedure was optimized. Linearity ranged from 0.70 ppb to 25 ppb. R.S.D. were in the range of 1-23% for the SPME step. Preliminary real samples were analyzed and a range of compounds was detected. The optimized MAE/SPME/GC-MS methodology promises to be useful for different applications.     

基于气相色谱-质谱联用技术的代谢组学方法在转植酸酶基因玉米代谢物指纹图谱分析中的应用

目的:建立气相色谱-质谱联用技术(GC-MS)的代谢组学方法,初步研究转基因株系与对照株系之间代谢物指纹图谱的差异性,为转基因作物安全的评价提供参考。方法:优化提取条件,考察色谱条件,并采用主成分分析(PCA)数据处理方法对转基因株系及对照进行模式识别。结果:优化了提取条件及色谱条件,建立了GC-MS的代谢组学方法,获得了小分子的代谢产物的表达谱,发现转基因与其对照之间呈现出显著性差异。结论:优化的GC-MS的代谢组学方法可以从代谢水平检测转基因作物,找出差异性,为转基因作物的检测与评价提供技术支持。     

Evaluation of the Soil Contamination of Tangier (Morocco) by the Determination of BTEX,PCBs, and PAHs

Benzene, toluene, ethylbenzene, and xylenes (BTEX), twelve polycyclic aromatic hydrocarbons (PAHs) and seven polychlorinated biphenyls (PCBs), were selected as pollutants to evaluate the contamination of soils in the urban and industrial areas of Tangier (Morocco). PAHs and PCBs were determined by gas chromatography-mass spectrometry (GC-MS) after a microwave-assisted extraction (MAE) and gel permeation chromatography (GPC) clean-up. BTEX were directly determined by head-space GC-MS. Results obtained in this study show the presence of high levels of BTEX and PAHs in the soil near the urban waste deposit. However, the analysis of pollutants in the other sampling sites provided comprehensive evidence that soils of Tangier city are not contaminated.     

Analysis of volatile fractions of Schisandra chinensis (Turcz.) Baill. using GC-MS and chemometric resolution

The two-dimensional data obtained from GC-MS has been used qualitatively and quantitatively to determine the components of the volatile fractions of Schisandra chinensis obtained by six different extraction methods. Sub-window factor analysis (SFA) was employed to confirm the identities of components determined in different samples. With the help of SFA, and other chemometric techniques, peak purity in the chromatograms was determined, and overlapping peaks were resolved to yield a pure chromatographic profile and mass spectrum for each component. It is demonstrated that the accuracy of qualitative and quantitative analysis may be greatly enhanced using chemometric resolution methods, such methods being particularly valuable with respect to the analysis of complex samples such as traditional Chinese medicines. It is further demonstrated that different extraction methods give rise to volatile fractions of S. chinensis which differ qualitatively and quantitatively in their composition.     

Bioactivity-guided discovery of quality control markers in rhizomes of Curcuma wenyujin based on spectrum-effect relationship against human lung cancer cells

BackgroundDue to the diversity of the ingredients, the complexity of the mechanism of action, the uncertainty of the effective ingredients, coupled with the multiple species and multiple growing areas, the quality control (QC) of Traditional Chinese Medicines (TCMs) is challenging. Discovering and identifying effective compounds from the complex extracts of TCMs and then establishing a scientific QC method is the key to the holistic QC of TCMs.PurposeTo develop an anti-lung-cancer-guided spectrum-effect relationship approach for the discovery of QC markers of the rhizome of Curcuma wenyujin (WEZ) and establish a bioactive compounds-based holistic QC method.MethodsThe chemical profiling of the volatile oil (WVO) from 42 batches of WEZ collected from different growing areas was performed by GC-MS. The anti-lung cancer activity of different WVO samples was determined by CCK-8 assay against human lung cancer cells (A549). The apoptosis and cell cycle analysis under different concentrations of WVO were detected by flow cytometry. SIMCA-P software was used to perform multivariate statistical analysis on the chemical composition of different WVO samples and to find the different components. Active compounds were screened using a PLSR model of the spectrum-effect relationship. Bioactive compounds-based fingerprint and quantification of the leading bioactive compounds were developed by GC-MS and GC-FID, respectively.ResultsSeventy-eight compounds were detected in WVO and 54 were successfully identified. The multivariate statistical analysis uncovered that WVO components and the anti-A549 activity of WVO at the concentration of 60 nl/ml differ greatly according to the origin of the plant. The WVO at the concentration of 60 nl/ml (IC₅₀) increased A549 cells apoptosis significantly with late and early apoptosis of 15.61% and 7.80%, and the number of cells in the G2/M phase were also increased significantly under this concentration. The spectrum-effect relationship analysis revealed that 44 compounds were positively correlated with their activities, and the result was verified by A549 cell viability assay. Sixteen positively correlated compounds were further selected as QC markers according to their relative amount > 0.5% and anticancer activity. Finally, the 16 QC markers-based GC-MS fingerprint was established to holistically control the quality of WEZ, and a GC-FID method was developed for the quantification of leading bioactive compounds, β-elemene and β-caryophyllene.ConclusionBased on an anti-lung-cancer-guided spectrum-effect relationship approach, the bioactive compounds-based holistic QC method was successfully developed for WEZ, which could provide a valuable reference for the QC of TCMs.     

固相微萃取—气相色谱—质谱联用分析蓼实挥发性成分

察了萃取样品温度、萃取纤维吸附时间等因素对于固相微萃取蓼实挥发性成分的影响,确定较佳的实验条件为：萃取样品温度60℃,萃取纤维吸附时间60 min,脱附温度250℃,脱附时间5 min。用气相色谱—质谱联用技术测定上述条件所得蓼实挥发性化学成分,并鉴定出其中43种,占总峰面积的76.73%。其中含量较高的物质有：罗汉柏烯 (6.99%),丁香烯 (5.59%),2,5,5,8 a-四甲基-6,7,8,8a 四氢-5H-萘-1-酮(5.52%),α-丁香烯(4.29%),1,2,4a,5,6,8a-六氢-4,7-二甲基-1-异丙基萘(4.04%),环氧石竹烯(3.60%),α-香附酮(3.54%),4,5,5a,6,6a,6b-6氢-4,4,6b-三甲基-2-乙烯基-2H-环丙香豆酮(3.54%),香叶基丙酮(3.48%)。     

灵芝子实体中三萜类物质抗肿瘤活性的谱效关系

通过HPLC指纹图谱结合多元线性回归分析对不同产地灵芝子实体的功效性特征进行评价,为寻找灵芝中活性三萜提供理论依据。利用高效液相分析方法,结合样品对肿瘤细胞L1210的增殖抑制率,运用“中药色谱指纹图谱相似度评价系统2004A版”软件和多元线性回归分析11批不同品种灵芝子实体中的三萜活性成分。样品与标准指纹图谱的相似度均在0.9以上,共标定了12个共有物质峰,其中与抗L1210肿瘤细胞活性关系密切的三萜物质有灵芝酸C₂、灵芝酸G、灵芝烯酸B、灵芝烯酸A、灵芝酸K、灵芝酸A、灵芝酸F和灵芝醛A。     

微波辅助提取龙葵中总生物碱的研究

本文对龙葵中总生物碱(Tocal steroidal alkaloids,)的微波辅助提取(Microwave-assisted extraction,MAE)工艺、作用机理及对成分的结构影响进行了系统的研究。以酸性染料比色法为分析手段,设计正交试验得到了最佳提取工艺：以95％乙醇为溶剂,料液比1：20,在585w下提取8min;用扫描电镜(SEM)对样品处理前后形貌进行了观察,揭示了微波作用机理与细胞结构变化有关。同时薄层色谱(TLC)、反相高效液相色谱(RP-HPLC)定性分析显示,微波对有效成分的结构没有造成影响。     

Development and application of microwave-assisted extraction technique in biological sample preparation for small molecule analysis

Microwave-assisted extraction (MAE) has emerged as an efficient extraction technique for various kinds of biological samples due to its low usage of extraction solvents and shorter extraction time. This review will focus on the recent developments and advantages of incorporating MAE in sample preparation protocols for the analysis of small molecules in plant, food and clinical samples in recent years. The operating principles of this technique and the key parameters influencing its extraction efficiency, including the nature of solvent, temperature, power and extraction time and their limitations are first mentioned. This is followed by a discussion on the advantages of applying MAE to extract organic contaminants in food for routine food safety analysis and active ingredients recovery. The successful application of MAE technique to recover bioactive compounds from plants in drug discovery studies and quality control purposes is then described. Additionally, the feasibility of using green solvents such as water, micelle and ionic liquids with MAE for plant metabolite profiling studies is evaluated and the associated challenges discussed. Finally, the application of MAE in clinical samples is highlighted. The use of MAE in this field is currently limited to the targeted detection of small molecules in human samples, due to a lack of knowledge of its effects on thermally labile metabolites. Consequently, the need for additional studies on how MAE impacts the recoveries of different metabolite classes in mammalian samples is discussed. The outcome of these studies can potentially broaden MAE applications in the clinical field.     

Extraction and identification of different prostaglandins in Allium cepa

Green onions (Allium cepa) were homogenized in a blender and extracted by normal extraction methods except that diethyl ether was used as the first extracting solvent. Different analytical procedures were used for the identification of the prostaglandins separated. TLC was applied using silica gel 60 F254 plates and a mixture of benzene, dioxane and acetic acid (20:10:1) as eluent, and the Rf values were compared with those of authentic samples. GC analysis on an SE 30 packed column and FID was applied; relative retention times of the onion extract components were measured and matched with authentic prostaglandin samples using cholesterol as an internal standard. GC-MS analyses using the same conditions adopted for GC analysis were conducted on a Finnigan MAT 112S instrument. Four peaks were identified. The prostaglandins identified were F1 alpha, E1, B1 and A2.     

HPLC fingerprinting and LC-TOF-MS analysis of the extract of Pseudostellaria heterophylla (Miq.) Pax root

High-performance liquid chromatographic (HPLC) was developed for fingerprint analysis of Pseudostellaria heterophylla (Miq.) Pax. Liquid chromatography-electrospray ionization-time-of-flight mass spectrometry (LC-TOF-MS) technique was first employed to identify the components of the fingerprint. Twelve major peaks in chromatographic fingerprint were analyzed by on-line LC-TOF-MS analysis; one cyclic peptide was unequivocally identified and five cyclic peptides were tentatively assigned based on their MS data. These cyclic peptides served as the marker peaks in the HPLC fingerprints. The chromatographic fingerprints have been analyzed by similarity index calculations and hierarchical clustering analysis (HCA). The result showed that the HPLC fingerprints could be used to determine the optimal harvest time for P. heterophylla (Miq.) Pax and to authenticate the species of the herb.     

Detection of new exemestane metabolites by liquid chromatography interfaced to electrospray-tandem mass spectrometry

Exemestane is an irreversible aromatase inhibitor used for anticancer therapy. Unfortunately, this drug is also misused in sports to avoid some adverse effects caused by steroids administration. For this reason exemestane has been included in World Anti-Doping Agency prohibited list. Usually, doping control laboratories monitor prohibited substances through their metabolites, because parent compounds are readily metabolized. Thus metabolism studies of these substances are very important. Metabolism of exemestane in humans is not clearly reported and this drug is detected indirectly through analysis of its only known metabolite: 17β-hydroxyexemestane using liquid chromatography coupled to tandem mass spectrometry (LC-MS/MS) and gas chromatography coupled to mass spectrometry (GC-MS). This drug is extensively metabolized to several unknown oxidized metabolites. For this purpose LC-MS/MS has been used to propose new urinary exemestane metabolites, mainly oxidized in C6-exomethylene and simultaneously reduced in 17-keto group. Urine samples from four volunteers obtained after administration of a 25mg dose of exemestane were analyzed separately by LC-MS/MS. Urine samples of each volunteer were hydrolyzed followed by liquid-liquid extraction and injected into a LC-MS/MS system. Three unreported metabolites were detected in all urine samples by LC-MS/MS. The postulated structures of the detected metabolites were based on molecular formulae composition obtained through high accuracy mass determination by liquid chromatography coupled to hybrid quadrupole-time of flight mass spectrometry (LC-QTOF MS) (all mass errors below 2ppm), electrospray (ESI) product ion spectra and chromatographic behavior.     

The study of fingerprint characteristics of the emanations from human arm skin using the original sampling system by SPME-GC/MS

An efficient and noninvasive method consisting of an original sampling device, solid phase microextraction (SPME) and gas chromatography-mass spectrometry (GC-MS) was developed to analyze volatile organic emanations from the skin of human arms. The emanations were sampled by SPME connected with the active sampling device for 30 min and transferred into GC-MS immediately for the consequent analysis. The sampling projects for 15 candidates were scheduled in both winter and spring with the same optimized conditions. Thirty-five compounds were finally identified according to various degrees of certainty. Different emission behaviors specified with principal component analysis (PCA) and similar fingerprint characteristics were observed clearly by comparisons of chromatograms of different seasons. Top ten emanations contributing to characteristics in different seasons were attempted to be described using comparisons based on common model strategy. The large amounts of experimental data were all handled by the corresponding chemometrics strategies with the homemade chromatographic data processing system. The results suggest that the analysis based on fingerprint characteristics of human skin emanations could provide useful and important clues to reveal biomarkers among the mixture of human skin emanations.     

Effectiveness of fine root fingerprinting as a tool to identify plants of the Alps: Results of a preliminary study

To identify plants of the Alps through analysis of their roots is currently extremely difficult when using traditional identification methods such as dichotomous keys and/or illustrated atlases. Besides genetic analysis, other analytical methods, such as chromatographic analysis, could also be useful for root identification. Chromatographic fingerprints of root extracts of six species (Betula pendula, Picea abies, Fagus sylvatica, Larix decidua, Fraxinus excelsior and Corylus avellana) were analyzed in order to understand whether these species have a chromatographic fingerprint that identifies them, and hence to ascertain whether they can be identified by applying the method of analysis presented below. One hundred and sixty-two root samples were collected in various areas of the Alps and subjected to high-performance liquid chromatography (HPLC) analysis. Multivariate analysis techniques (e.g. cluster analysis) were employed for statistical analysis of chromatographic fingerprints. This study revealed that the chromatographic fingerprints of birch, spruce and larch samples were similar and that the method can therefore clearly identify the respective species. Instead, chromatographic fingerprint samples of beech, hazel and ash presented greater variability. Research proposals based on the results obtained in this study were also developed in order to implement and facilitate studies regarding plant roots.     

Optimization of a rapid microwave-assisted extraction method for the simultaneous determination of opiates,cocaine and their metabolites in human hair

A rapid and cleanup-free microwave-assisted extraction (MAE) method is proposed for the simultaneous extraction of six illegal drugs of abuse – cocaine, benzoylecgonine (BZE), cocaethylene (CCE), morphine, 6-monoacethylmorphine (6AM) and codeine – from human hair samples. The analytes were determined using high performance liquid chromatography (HPLC) with photodiode array UV detection. The influence of several variables on the efficiency of the MAE procedure was investigated in detail by a multi-objective optimization approach based on a hybrid experimental design (17 experiments) and desirability functions. Six drugs were successfully extracted from human hair with recoveries close to 100% and good reproducibility (<3.6% RSD) under the optimal MAE conditions: 11 mL dichloromethane (DCM) extraction solvent, 60 °C extraction temperature, 9 min extraction time and 0.5 mL of methanol (MeOH) added to 50 mg of the hair sample in the extraction vessels. Limits of quantification of 0.2 ng mg^?1 were found for the studied compounds. A comparison of sample preparation procedures, including MAE, enzymatic digestion and digestion by aqueous acids, was also conducted. The results indicated that the global behaviour of sample procedures provided similar satisfactory recoveries ranging from 86 to 100%. Indeed, the MAE procedure resulted in a reduction of extraction time by 100-fold and the elimination of cleanup steps. Slightly higher recoveries of morphine, 6AM, BZE and CCE, at 1 ng mg^?1 concentration level and cocaine at 40 ng mg^?1 concentration level, were achieved using MAE. Lastly, the proposed MAE method was applied to several human hair samples from multidrug abusers.     

芦荟的HPLC指纹图谱建立、化学模式识别分析及其含量测定

采用Phenomenex C18色谱柱(250 mm×4.6 mm,5 μm),以甲醇-乙腈-0.3％磷酸水为流动相进行梯度洗脱,建立芦荟的指纹图谱.运用化学模式识别方法对不同产地芦荟药材质量控制方法进行评价.结果表明:12批芦荟HPLC指纹图谱共标定23个共有峰,并通过对照品指认其中6个成分;除了广西的3批药材之外,...     

微波辅助提取荔枝核黄酮类化合物及其抗氧化性研究

研究微波辅助法提取荔枝核黄酮类化合物的工艺,考察了提取溶剂、微波功率、溶剂用量、辐射时间、提取次数等因素对提取的影响。通过正交实验确定最佳的提取参数为:60%乙醇作为提取溶剂,微波功率700 W,料液比1∶25,辐射时间150 s,提取一次。在此优化条件下用微波辅助,黄酮类化合物的得率为6.86%,提取物中黄酮含量达到36.7%。抗氧化性研究表明荔枝核黄酮类化合物有良好的抗氧化活性,能有效清除羟基自由基(OH.)和超氧阴离子自由基(O2-.)。     

Analysis of influences of spaceflight on chemical constituents in licorice by HPLC–ESI-MS/MS

Focusing on the variations of chemical constituents in licorice root, influences of exposure to physical factors of spaceflight on licorice (Glycyrrhiza uralensis Fisch.) seeds were investigated. Licorice seeds obtained from two different producing areas were flown on a recoverable satellite for 18 days. After returning to earth, the seeds carried by the satellite and the parallel ground control were cultivated to maturity under the same condition. Chromatographic fingerprint of 1 year licorice root analyzed by high performance liquid chromatography with diode-array detection not only displayed the contents of glycyrrhizic acid and liquiritin increasing in the spaceflight samples but showed the variation of the kinds of chemical constituents. The main components in the root extract were identified by high performance liquid chromatography coupled with electrospray ionization multi-tandem mass spectrometry. The changes in the kind of secondary metabolites of licorice root after spaceflight were firstly reported. A total of 26 components which included 9 flavonoids, 16 triterpene saponins and 1 coumarin were identified according to their mass spectra determined in both negative and positive ion modes. The research provided the scientific data for spaceflight breeding of medicinal plant and indicated that the technology of spaceflight may be a new effective method for the breeding and cultivation of licorice.     

Determination and occurrence of polybrominated diphenyl ethers in maternal adipose tissue from inhabitants of Singapore

Polybrominated diphenyl ethers (PBDEs), as a specific group of brominated flame retardants (BFR), are used in a variety of consumer products including electronics and household furnishings. In recent years, a marked increase in the levels of PBDEs in human biological tissues and fluids, especially breast milk, has been reported in several countries. However, few data are available from countries in the Asia-pacific region, including Singapore. This study presents a validated method procedure and the first available data of the concentrations of PBDE congeners: PBDE-47 (2,2,4,4-Tetrabromodiphenyl ether), PBDE-99 (2,2',4,4',5-Pentabromodiphenyl ether), PBDE-100 (2,2',4,4',6-Pentabromodiphenyl ether), PBDE-153 (2,2',4,4',5,5'-Hexabromodiphenyl ether), PBDE-154 (2,2',4,4',5,6'-Hexabromodiphenyl ether) in maternal adipose tissue collected from inhabitants of Singapore. Microwave-assisted extraction (MAE) of PBDEs spiked adipose tissues coupled with GC-MS analysis achieved comparable recoveries to a conventional Soxhlet Extraction (SE) procedure of between 70 and 130%. MAE also yielded comparable precision data (variance less than 13%) relative to the SE procedure. Spiked Carbon-13 PBDE congeners were also used as surrogates for MAE quality assurance and confirmed the efficiency of the procedure. PBDE congeners were detected in all of 16 maternal adipose tissues collected in Singapore, where levels were comparable to available data from Belgium.