Headspace Solid-Phase Micro-Extraction Gas Chromatography/Mass Spectrometry(HS-SPME-GC/MS)-Based Untargeted Metabolomics Analysis for Comparing the Volatile Components from 12 Panax Herbal Medicines

Quality control of ginseng currently is mainly based on ginsenoside analysis,but rarely focuses on the volatile organic components.In the current work,an untargeted metabolomics approach,by headspace solid-phase micro-extraction gas chromatography/mass spectrometry(HS-SPME-GC/MS),was elaborated and further employed to holistically compare the compositional difference of the volatile components simultaneously from 12 Panax herbal medicines,which included P.ginseng(PG),P.quinquefolius(PQ),P.notoginseng(PN),red ginseng(PGR),P.ginseng leaf(PGL),P.quinquefolius leaf(PQL),P.notoginseng leaf(PNL),P.ginseng flower(PGF),P.quinquefolius flower(PQF),P.notoginseng flower(PNF),P.japonicus(PJ),and P.japonicus var.major(PJvm).Chromatographic separation was performed on an HP-5MS elastic quartz capillary column using helium as the carrier gas,enabling good resolution within 1 h.We were able to characterize totally 259 volatile compounds,including 82 terpenes(T),46 alcohols(Alc),29 ketones(K),25 aldehydes(Ald),21 esters(E),and the others.By analyzing 90 batches of ginseng samples based on the untargeted metabolomics workflows,236 differential ions were unveiled,and accordingly 36 differential volatile components were discovered.It is the first report that simultaneously compares the compositional difference of volatile components among 12 Panax herbal medicines,and useful information is provided for the quality control of ginseng aside from the well-known ginsenosides.

Comparison of simultaneous distillation extraction and solid-phase micro-extraction for determination of volatile constituents in tobacco flavor

The volatile and semi-volatile components in tobacco flavor additives were extracted by both simultaneous distillation extraction and solid-phase micro-extraction. Extraction conditions for solid-phase micro-extraction were optimized with information theory. Then, detection were accomplished by gas chromatography-mass spectrometry. Characteristic of each method was compared. Qualitative analysis and quantitative analysis of 6# tobacco flavor sample were accomplished through both simultaneous distillation extraction and solid-phase micro-extraction. The experimental results show that solid-phase micro-extraction method is the first choice for qualitative analysis and simultaneous distillation extraction is another good selection for quantitative analysis. By means of simultaneous distillation extraction, 20 components are identified, accounting for 92.77% of the total peak areas. Through solid-phase micro-extraction, there are 17 components identified accounting for 91.49% of the total peak areas. The main aromatic components in 6# tobacco flavor sample are propanoic acid, 2-hydroxy-, ethyl ester, menthol and menthyl acetate. The presented method has been successfully used for quality control of tobacco flavor.

Determination of Aroma Composition of Santalum album Linn by Solid-phase Microextraction-Gas Chromatography-Mass Spectrometry

[Objectives]This study aimed to determine the volatile components in Santalum album Linn and gradually clarify the aroma composition of S.album Linn.[Methods]Solid-phase microextraction method was used to obtain the volatile components of S.album Linn.The aroma components were analyzed by gas chromatography-mass spectrometry and their relative contents were calculated using the area normalization method.[Results]In a dry state at room temperature,39 chemical components were identified from S.album Linn,mainly olefins(91.15%),alkanes(3.00%),alcohols(2.56%),esters(2.19%),ketones(0.55%),aldehydes(0.41%)and heterocyclics(0.14%).[Conclusions]This method has the advantages of low sample consumption,easy operation,rapid identification of aroma components and high sensitivity,and can effectively separate and determine volatile components in S.album Linn,realizing the rapid identification of different S.album Linn varieties and providing technical support for further research on Chinese medicinal materials.

Mapping the metabolic responses to oxaliplatin-based chemotherapy with in vivo spatiotemporal metabolomics

Adjuvant chemotherapy improves the survival outlook for patients undergoing operations for lung metastases caused by colorectal cancer (CRC). However, a multidisciplinary approach that evaluates several factors related to patient and tumor characteristics is necessary for managing chemotherapy treatment in metastatic CRC patients with lung disease, as such factors dictate the timing and drug regimen, which may affect treatment response and prognosis. In this study, we explore the potential of spatial metabolomics for evaluating metabolic phenotypes and therapy outcomes during the local delivery of the anticancer drug, oxaliplatin, to the lung. 12 male Yorkshire pigs underwent a 3 h left lung in vivo lung perfusion (IVLP) with various doses of oxaliplatin (7.5, 10, 20, 40, and 80 mg/L), which were administered to the perfusion circuit reservoir as a bolus. Biocompatible solid-phase microextraction (SPME) microprobes were combined with global metabolite profiling to obtain spatiotemporal information about the activity of the drug, determine toxic doses that exceed therapeutic efficacy, and conduct a mechanistic exploration of associated lung injury. Mild and subclinical lung injury was observed at 40 mg/L of oxaliplatin, and significant compromise of the hemodynamic lung function was found at 80 mg/L. This result was associated with massive alterations in metabolic patterns of lung tissue and perfusate, resulting in a total of 139 discriminant compounds. Uncontrolled inflammatory response, abnormalities in energy metabolism, and mitochondrial dysfunction next to accelerated kynurenine and aldosterone production were recognized as distinct features of dysregulated metabolipidome. Spatial pharmacometabolomics may be a promising tool for identifying pathological responses to chemotherapy.

Determining organic compounds in coking wastewater by SPME-GC /MS

The solid-phase microextraction （SPME） combined with gas chromatography/mass spectrometry （GC/MS） was used to determine and analyze organic pollutants in coking wastewater. Based on the fact that the main compounds in the wastewater were organics, some key parameters of the SPME were optimized. The method has good linearity （ its correlation coefficients 〉 0.99） in the range determined,its relative standard deviations （RSD） are less than 15%, and its recovery is from 87.9% to 128.1% with the lowest quantification limit of 5 ~g/L. This method has been used to measure 15 organic pollutants in wastewater from a certain coking plant. The results show that compared with the conventional method,it can save an hour in pretreatment time. It is a fast, low-cost, accurate, simple and efficient analytical method indeed.

Analysis on Volatile Components of Flowers and Leaves of Thymus mongolicus by SPME-GC/MS

[Objectives] To analyze volatile components of flowers and leaves of Thymus mongolicus. [Methods]Volatile components of collected T. mongolicus flower and leaves were separated by headspace solid-phase microextraction( SPME) and identified by gas chromatography/mass spectrometry( GC/MS) and normallized by peak area. [Results] A total of 24 and 14 compounds were identified from flowers and leaves of T. mongolicus in the total ion chromatogram,accounting for 99. 573% and 97. 187% of the total peak area,respectively. Main components of flowers and leaves of T. mongolicus include phenols and terpenes,and thymol accounts for 35. 38% and 49. 13% of flowers and leaves of T. mongolicus,respectively. [Conclusions] SPME-GC/MS can be applied in analyzing volatile components of flowers and leaves of T. mongolicus,to provide basis for further development and utilization of T. mongolicus.

Combination of Solid-Phase Micro-Extraction and Direct Analysis in Real Time-Fourier Transform Ion Cyclotron Resonance Mass Spectrometry for Sensitive and Rapid Analysis of 15 Phthalate Plasticizers in Beverages

A method for rapid identification and quantification of phthalate plasticizers in beverages was developed.A number of 15 phthalate plasticizers which covered all the phthalates concerned in the US Consumer Product Safety Improvement Act(CPSIA),European Union legislations and Chinese national standards(GB)were analyzed.By a combined solid-phase micro-extraction(SPME)and direct analysis in real time mass spectrometry(DART-MS)approach,phthalates at sub-ng•mL^(−1)levels can be qualitatively and quantitatively analyzed in a short time.The use of ultrahigh-resolving power and the accurate mass measurement capacity naturally provided by Fourier transform ion cyclotron resonance mass spectrometry(FT-ICR-MS)minimizes the matrix interferences and thus enables the evaluation of phthalates in a complex matrix without extensive sample handlings or preparations.The limits of quantification(LOQs)were estimated to be at 0.3-5.0 ng•mL^(−1),lower than the Maximum Residue Limit(MRL)regulated by the European Union legislations(2007/19/EC)in foods,beverages,food packaging and toys(0.3-30 ng•mL^(−1)).This rapid and easy-to-use SPME-DART-FT-ICR-MS method provided a relatively high-throughput and powerful analytical approach for quick testing and screening phthalates in beverages and water samples to ensure food safety.

固相微萃取-气相色谱-质谱联用鉴别荚醚N,N,N',N'-四丁基-3-氧-戊二酰胺辐射产物

N,N,N′,N′-四丁基-3-氧-戊二酰胺(TBOPDA)是一种新合成的萃取剂,它可以在高酸度情况下萃取铀等锕系元素[1],在高废液的萃取处理中具有良好的应用前景.曾有报道采用GC方法分析辐照后的气相产物[2],本文采用固相微萃取技术萃取TBOPDA部分挥发性和半挥发性液相辐照产物,结合GC-MS进行鉴定,确定了其液相辐照产物主要为二丁胺、二正丁基甲酰胺、二正丁基乙酰胺.……

烤制时间对中式烤五花肉挥发性风味物质的影响

以猪五花肉为研究对象,利用万能蒸烤箱,研究恒定温度160℃条件下,不同烤制时间(5,10,15,20,25 min)对中式烤五花肉挥发性物质的影响。运用顶空固相微萃取(solid-phase microextraction,SPME)和气相色谱-质谱(gas chromatography-mass spectrometry,GC-MS)联用仪进行分析和鉴定,研究结果表明,中式烤五花肉在烤制时间下共鉴定出40种挥发性风味物质,其中醛类化合物7种、酯类化合物4种、醇类化合物8种、烃类化合物14种、其他化合物7种。从不同时间段来看,中式烤五花肉在烤制过程中,随着烤制时间的变化,在烤制25 min的条件下产生的挥发性物质数量最多。

六种特级初榨橄榄油挥发性香气成分的比较

为探究比较特级初榨橄榄油挥发性香气成分,采用固相微萃取(solid phase micro-extraction,SPME)结合气相色谱嗅闻质谱(gas chromatography-olfactrometry-mass spectrometry,GC-O-MS)联用、感官评价和电子鼻技术对3个国家的6种特级初榨橄榄油挥发性香气成分进行分析。结果表明,电子鼻可以明显区分不同橄榄油;GC-O-MS通过极性色谱柱(DB-Wax)和非极性色谱柱(DB-5)结合分析,鉴定得出65种挥发性香气活性化合物,包括醛类16种,醇类12种,酯类9种,酮类6种,烯烃及萜烯类8种,芳香类5种,酸类3种及6种其他类型化合物。结合文献、检测及嗅闻结果得出特级初榨橄榄油中的特征香气成分为反-2-己烯醛、己醛、反-2-壬烯醛、6-甲基-5-庚烯-2-酮和顺-3-己烯-1-醇等以醛醇为代表的小分子化合物。

Determination of Volatile Constituents,Total Flavonoids and Total Polysaccharides in the Roots of Artemisia argyi Levl. et Van. var.argyi cv. Qiai

[Objectives] To analyze the volatile components,the contents of total flavonoids and total polysaccharides of the roots of Artemisia argyi Levl. et Van. var. argyi cv. Qiai,and to provide a scientific basis for the comprehensive development and utilization of the resources.[Methods]The volatile components of the roots were extracted by solid phase micro-extraction( SPME),and its volatile components were analyzed by gas chromatography-mass spectrometry( GC-MS); the contents of total flavonoids and total polysaccharides in the samples were measured by UV-spectrophotometry. [Results] 44 peaks were isolated from the roots and 30 components were identified,accounting for 80. 9% of the total volatile components; the content of total flavonoids in the roots was 9. 42%; the content of total polysaccharides in the roots was 11. 05%.[Conclusions] After a comprehensive investigation,the olefins in the roots generally have antibacterial activity,the contents of the total flavonoids and total polysaccharides contained in the roots were relatively high,the roots of Artemisia argyi do have broad prospects for the development.

Processing impact on volatile compounds profile in higholeic and normal peanut oil

With the improvement of living quality, high-oleic peanuts have drawn people’s attention. Increasing oleic acid content of peanut oil should be desired for improving shelf life and potential health benefits. The flavor is among the most important quality attributes for commercial acceptance of peanuts products. The volatile components of high-oleic pea-nuts oil and normal-oleic lines were compared in this research. First, volatile components of peanut oils were analyzed and identified by solid-phase microextraction/gas chroma- tography/mass spectrometry （SPME/GC/MS）. Then principal components analysis （PCA） was used to identify principal volatile components in peanut oils of different cultivars fo卜 lowing three different processing methods, including roasting, boiling and roasting, and roasting by microwave-assisted. The results showed that there were obvious differences of the volatile components between high-oleic and normal peanut oils. Among different pro-cessing method of peanuts, there was no clear separation on volatile components observed between roasting and boiling and roasting by microwave-assisted. Moreover, the same genotype had the similar flavor characteristic. Different processing methods had no signifi-cant effect on volatile components in peanut oils.

A study revealing the key aroma compounds of steamed bread made by Chinese traditional sourdough

Aroma of Chinese steamed bread（CSB） is one of the important parameters that determines the overall quality attributes and consumer acceptance. However, the aroma profile of CSB still remains poorly understood, mainly because of relying on only a single method for aroma extraction in previous studies. Therefore, the objective of this study was to determine the volatile aroma compounds of five different samples of CSB using three different aroma extraction methods, namely solid-phase microextraction（SPME）, simultaneous distillation–extraction（SDE）, and purge and trap（PT）. All samples showed a unique aroma profile, which could be attributed to their unique microbial consortia.（E）-2-Nonenal and（E,E）-2,4-decadienal were the most prevalent aromatic compounds revealed by SDE, which have not been reported previously, while ethanol and acetic acid proved to be the most dominant compounds by both SPME and PT. Our approach of combining three different aroma extraction methods provided better insights into the aroma profile of CSB, which had remained largely unknown in previous studies.

QSRR Study of GC Retention Indices of Volatile Compounds Emitted from Mosla chinensis Maxim by Multiple Linear Regression

The volatile compounds emitted from Mosla chinensis Maxim were analyzed by headspace solid-phase micro- extraction （HS-SPME） and headspace liquid-phase microextraction （HS-LPME） combined with gas chromatography-mass spectrometry （GC-MS）. The main volatiles from Mosla chinensis Maxim were studied in this paper. It can be seen that 61 compounds were separated and identified. Forty-nine volatile compounds were identified by SPME method, mainly including myrcene, a-terpinene, p-cymene, （E）-ocimene, thymol, thymol acetate and （E）-fl-farnesene. Forty-five major volatile compounds were identified by LPME method, including a-thujene, a-pinene, camphene, butanoic acid, 2-methylpropyl ester, myrcene, butanoic acid, butyl ester, a-terpinene, p-cymene, （E）-ocimene, butane, 1,1-dibutoxy-, thymol, thymol acetate and （E）-fl-farnesene. After analyzing the volatile compounds, multiple linear regression （MLR） method was used for building the regression model. Then the quantitative structure-retention relationship （QSRR） model was validated by predictive-ability test. The prediction results were in good agreement with the experimental values. The results demonstrated that headspace SPME-GC-MS and LPME-GC-MS are the simple, rapid and easy sample enrichment technique suitable for analysis of volatile compounds. This investigation provided an effective method for predicting the retention indices of new compounds even in the absence of the standard candidates.