光皮木瓜果实中香气成分的GC-MS分析

以成熟光皮木瓜为试样,采用顶空固相微萃取与气质联用方法分析检测木瓜果实中的香气成分,共鉴定出43种香气成分,占总峰面积的92.89%。含量较高的依次为2-己烯醛、反式-2-甲基-环戊醇、(E,E)-2,4-己二烯醛、2-丁酮、(Z)-3-己烯醛、醋酸乙酯、(E)-3-己烯-1-醇、茶香螺烷等。其中C6化合物占总量的70%以上,因此可以确定C6化合物是构成光皮木瓜果实清香味的主要成分。     

气相色谱-质谱法分析啤酒中酒花香气成分

利用顶空固相微萃取-气相色谱质谱技术(HS-SPME/GC-MS)建立了定量分析啤酒中19种源自酒花的微量香气成分的方法。研究了不同萃取头、萃取时间、萃取温度对萃取效果的影响,最终确定HS-SPME最佳萃取条件为采用PDMS萃取头对啤酒样品在50℃下萃取60 min。在最佳萃取条件下,采用啤酒为基体以减少基体干扰,建立标准曲线,随后在SIM模式下以萜品烯-4-醇为内标定量测定了啤酒中酒花香气物质的含量。19种物质的回收率在81.2%～116.8%之间,相对标准偏差(RSD)低于9.8%,在5个加标浓度下,R2大于0.99。相比于传统方法,本方法所需样品量少、灵敏度高、操作过程简便,能准确的检测出啤酒中酒花香气物质的含量。     

顶空固相微萃取-气相色谱质谱联用技术分析甜樱桃芳香成分

采用固相微萃取技术(SPME)提取‘红灯’甜樱桃果实芳香成分,运用气相色谱-质谱-计算机联用技术进行芳香成分分析,共检测出41种芳香成分,占总峰面积的98.81%,质量分数较高的芳香成分依次为反-1,4-己二烯、己醛、2-己烯醛、(E)-2-乙烯-1-醇、1-己醇、乙醇(、E,E)-2,4-己二烯醛、己酸乙酯、苯甲醛等。     

固相微萃取气质联用分析茉莉花的香气成分

利用顶空固相微萃取技术,采用气质联用仪分析茉莉花的香气成分,在弱极性和极性毛细管色谱柱条件下,分别用PDMS、PDMS/DVB、PA三种萃取头富集香气,分离出100多种香气成分,鉴定出含量大于0.1%的55种组分,占香气成分的97%,三种萃取头所得主成分完全一致,均为芳樟醇、乙酸苄酯、反式-金合欢烯、顺式-苯甲酸-3-己烯酯和吲哚。     

固相微萃取-气相色谱-质谱测定杨梅香气

对利用固相微萃取-气相色谱-质谱联用仪分析杨梅果汁香气成分过程中的萃取及色谱质谱条件等关键因素进行了研究.通过优化条件,确定最佳萃取条件为:8 mL果汁加入1 g NaCl,50/30 μm的DVB/CAR/PDMS纤维头在50 ℃下萃取30 min.气质分析时,采用小直径衬管,并控制合适的质谱条件,可提高痕量组分响应及匹配度.通过面积归一法,确定杨梅香气主要成分为:4种烯类物质,约占62.59%;8种醇类物质,约12.68%;2种酯类,约0.89%.     

中华猕猴桃果实香气成分的气相色谱/质谱分析

1 引言。猕猴桃(Actinidia Chinensis)原产我国,又称阳桃、羊桃、藤梨等,属猕猴桃科猕猴桃属。由于其气味香醇以及含有丰富的维生素、氨基酸和矿物质成分,深受广大消费者的喜爱。中华猕猴桃由于其特殊的香醇气味已经被加工为猕猴桃果汁、猕猴桃果酒。因此研究其特殊的香醇气味对发展猕猴桃的深加工有重要的意义。香气成分是构成和影响水果及其     

龙井茶特征香气成分分析及种类判别

采用顶空固相微萃取(HS-SPME)和气相色谱-质谱(GC-MS)联用技术分析了39份龙井茶叶中的挥发性成分,结合质谱数据库与保留指数,从24份西湖核心区龙井茶中获得了200余种挥发性化合物,这些挥发性成分中主要含有醇类、酯类、酮类、杂环类等化合物,经筛选得到26种共有组分.并采用主成分分析法(PCA)对24份西湖核心区龙井茶和15份疑似龙井茶进行了有效区分.该方法适用于茶叶的品质鉴定、真假识别、产地溯源等方面的研究,也为其他产品的挥发性成分分析提供参考.     

花生微波烘烤香气成分分析方法的建立与应用

建立了烤制花生香气成分分析的顶空固相微萃取/气相色谱-质谱(HS SPME/GC-MS)分析方法。优化的实验条件:HP-5色谱柱,萃取平衡温度80℃,萃取时间40 min,解析时间5 min。采用该方法对四粒红、大白沙、鲁花3种花生进行微波炉焙烤后产生的挥发性香气成分进行分析,共鉴定出29种成分,其中主要包括杂环类化合物9种,醛类化合物7种,醇类化合物3种,烯类化合物3种,酚类化合物2种,酯类化合物3种,其他化合物2种。根据上述风味物质对花生香味的贡献大小,选择7种主要特征香气成分2,5-二甲基吡嗪、2-乙基-3,5(6)-二甲基吡嗪、2-乙基-6-甲基吡嗪、2-戊基呋喃、2,3-二氢苯并呋喃、苯甲醛和苯乙醛进行定量分析,其标准曲线相关系数均超过0.997,标准物质的加标回收率为85%~101%,RSD不大于6.9%,检出限为0.63~13.4μg/L。比较了不同花生品种的香气差异,并通过分析不良风味成分苯乙醛的含量,发现以大白沙花生的特征香气浓度最高,苯乙醛含量最低,更适宜利用微波烘焙技术生产咸干花生食品。     

固相微萃取-气相色谱-质谱法分析香樟籽挥发性成分

采用固相微萃取-气相色谱-质谱法分离和鉴定香樟籽的挥发性成分,用归一化法测定其相对含量。共分离出76种组分,鉴定出47种化合物,其含量占总挥发性成分的97.4%。主要挥发成分为樟脑(57.89%)、柠檬烯(12.68%)、α-蒎烯(4.42%)、莰烯(2.69%)、香橙烯(2.34%)、伞花烃(2.26%)及β-蒎烯(2.12%)。     

新一代萃取分离技术──固相微萃取

介绍了一种新型样品制备法——固相做萃取（SPME）的原理及其应用。与其它样品制备技术相比,SPME法具有操作时间短、样品量小、无需萃取溶剂、适于分析挥发性与非挥发性物质、重视性好等优点。     

Antioxidant,Antimicrobial Activities and Characterization of Polyphenol-Enriched Extract of Egyptian Celery (Apium graveolens L., Apiaceae) Aerial Parts via UPLC/ESI/TOF-MS

Medicinal plant extracts are increasingly considered a major source of innovative medications and healthcare products. This study focused on preparing a polyphenol enriched water extract of Egyptian celery “Apium graveolens L., Apiaceae” aerial parts (TAE) in an endeavor to accentuate its antioxidant capacity as well as its antimicrobial activity. (TAE) of celery was partitioned against different organic solvents to yield dichloromethane (DCM), ethyl acetate (EAC), and butanol (BUOH) fractions. (TAE) and the organic fractions thereof besides the remaining mother liquor (ML) were all screened for their antioxidant capacity using various protocols viz. monitoring the reducing amplitudes for ferric ions (FRAP), and radical scavenging potentials of oxygen (ORAC), 2,2’-azino-bis-3-ethylbenzothiazoline-6-sulfonic acid (ABTS), 2,2-diphenyl-1-picrylhydrazyl (DPPH), and metal chelation assays. The examination procedure revealed both (TAE) extract and (DCM) fraction, to pertain the highest antioxidant potentials, where the IC₅₀ of the (TAE) using ABTS and metal chelation assays were ca. 34.52 ± 3.25 and 246.6 ± 5.78 µg/mL, respectively. The (DCM) fraction recorded effective results using the FRAP, ORAC, and DPPH assays ca. 233.47 ± 15.14 and 1076 ± 25.73 μM Trolox equivalents/mg sample and an IC₅₀ 474.4 ± 19.8 µg/mL, respectively. Additionally, both (TAE) and (DCM) fraction exerted antimicrobial activities recording inhibition zones (mm) (13.4 ± 1.5) and (12.0 ± 1.0) against Staphylococcus aureus and (11.0 ± 1.2) and (10.0 ± 1.3) against Escherichia coli, respectively, with no anti-fungal activity. Minimum inhibitory concentration (MIC) of (TAE) and (DCM) fraction were 1250 and 2500 µg/mL, respectively. UPLC/ESI/TOF-MS unveiled the chemical profile of both (TAE) and (DCM) fraction to encompass a myriad of active polyphenolic constituents including phenylpropanoids, coumarins, apigenin, luteolin, and chrysoeriol conjugates.     

Determination of Chemical Composition,In Vitro and In Silico Evaluation of Essential Oil from Leaves of Apium graveolens Grown in Saudi Arabia

The aim of this study was to explore the composition and evaluate the in silico and in vitro antioxidants and antimicrobial and anti-inflammatory effects of Apium graveolens var. dulce leaves essential oil (AGO) collected from Al-Kharj (Saudi Arabia). AGO was isolated using the hydro-distillation method, and its composition was studied using gas-chromatography-mass Spectrometry (GC–MS), antimicrobial activities using well diffusion assay, and antioxidant and anti-inflammatory activities using spectrophotometric methods. The pharmacological activities of their major compounds were predicted using PASS (prediction of activity spectra for substances) and drug-likening properties by ADME (absorption, distribution, metabolism, and excretion) through web-based online tools. Isocnidilide (40.1%) was identified as the major constituent of AGO along with β-Selinene, Senkyunolide A, Phytyl acetate, and 3-Butylphthalide. AGO exhibited a superior antibacterial activity, and the strongest activity was detected against Gram-positive bacteria and Candida albicans. Additionally, it exhibited a weaker antioxidant potential and stronger anti-inflammatory effects. PASS prediction supported the pharmacological finding, whereas ADMET revealed the safety of AGO. The molecular docking of isocnidilide was carried out for antibacterial (DNA gyrase), antioxidant (tyrosinase), and anti-inflammatory (cyclooxygenase-2) activities. The docking simulation results were involved hydrophilic interactions and demonstrated high binding affinity of isocnidilide for anti-inflammatory protein (cycloxygenase-2). The presence of isocnidilide makes AGO a potential anti-inflammatory and antimicrobial agent. AGO, and its major metabolite isocnidilide, may be a suitable candidate for the future drug development.     

三种丁香花精油的挥发性成分比较分析

为了解紫丁香、白丁香和红丁香花蕾精油样品挥发性成分的差异,采用气相色谱-质谱联用技术（GC-MS）分析了三种丁香花精油样品的挥发性成分,并对三者的挥发性成分进行了主成分分析和聚类分析。结果从紫丁香、白丁香和红丁香精油中分别解析出46、64和56种挥发性物质,包括烷烃类、酯类、醇类、酮类、烯烃类、酚类、有机酸等,其中共有的挥发性成分为9种。三种丁香花精油样品的挥发性成分比较分析显示,酯类是含量最高的挥发性成分,其次是烷烃类,并且这两类物质在不同品种的丁香花精油中含量不同。统计分析结果表明三种样品的挥发性成分之间没有明显差别。本研究为增加丁香花精油的应用范围提供了理论依据。     

顶空固相微萃取-气相色谱-质谱法分析莪术的挥发油成分

采用顶空固相微萃取-气相色谱-质谱法分离和鉴定莪术挥发油成分,用归一化测定其相对含量。共分离出64个组分,鉴定出57种化合物,其含量占总挥发油组分峰面积98.02%。主要挥发成分及其含量为β-榄香稀(18.73%)、β-榄烯酮(11.03%)、莪术二酮(8.47%)、γ-榄香稀(6.79%)。     

南瓜子油的气相色谱-质谱分析

黑龙江产白皮南瓜子油脂含量约为27％，从提取的南瓜子油中检测出大量的共轭亚油酸、磷脂、角鲨烯、环烷烃、共轭不饱和醛酮、植物甾醇等化学成分，其中植物甾酵的含量约占南瓜子油的1％，能确定结构的甾醇有6种。     

Antioxidant Activity and Molecular Docking Study of Volatile Constituents from Different Aromatic Lamiaceous Plants Cultivated in Madinah Monawara,Saudi Arabia

A comparative study of volatile constituents, antioxidant activity, and molecular docking was conducted between essential oils from Mentha longifolia L., Mentha spicata L., and Origanum majorana L., widely cultivated in Madinah. The investigation of volatile oils extracted by hydrodistillation was performed using Gas Chromatography-Mass Spectrometry (GC-MS). A total number of 29, 42, and 29 components were identified in M. longifolia, M. spicata, and O. majorana representing, respectively, 95.91, 94.62, and 98.42, of the total oils. Pulegone (38.42%), 1,8-cineole (15.60%), menthone (13.20%), and isopulegone (9.81%) were the dominant compounds in M. longifolia oil; carvone (35.14%), limonene (27.11%), germacrene D (4.73%), and β-caryophyllene (3.02%) were dominant in M. spicata oil; terpin-4-ol (42.47%), trans-sabinene hydrate (8.52%), γ-terpinene (7.90%), α-terpineol (7.38%), linalool (6.35%), α-terpinene (5.42%), and cis-sabinene hydrate (3.14%) were dominant in O. majorana oil. The antioxidant activity, assessed using DPPH free radical–scavenging and ABTS assays, was found to be the highest in O. majorana volatile oil, followed by M. spicata and M. longifolia, which is consistent with the differences in total phenolic content and volatile constituents identified in investigated oils. In the same context, molecular docking of the main identified volatiles on NADPH oxidase showed a higher binding affinity for cis-verbenyl acetate, followed by β-elemene and linalool, compared to the control (dextromethorphan). These results prove significant antioxidant abilities of the investigated oils, which may be considered for further analyses concerning the control of oxidative stress, as well as for their use as possible antioxidant agents in the pharmaceutical industry.     

Determination of Inhalational Anesthetics in Field and Laboratory by SPME GC/MS

Exposure to inhalational anesthetics in health care workers could lead to several diseases and disorders. This study examined the applicability of solid phase microextraction for sampling and quantification of three inhalational anesthetics including; halothane, isoflurane, and sevoflurane in operating room air. Carboxen-Polydimethylsiloxane in retracted mode was selected and the effects of environmental parameters including temperature, humidity, and air velocity, were studied. There were no significant differences between sampling rates determined at different temperatures and air velocities. On the opposite, relative humidity has a significant effect on sampling rates. Comparison of the results between the developed SPME method and OSHA 103 method on standard test atmosphere and field showed satisfactory agreement.     

顶空固相微萃取-气相色谱-质谱联用分析纺织品中挥发性有机物

建立了顶空固相微萃取（HSSPME）-气相色谱（GC）-质谱（MS）联用测定纺织品中甲苯、4-乙烯基环己烯、苯乙烯、萘和1-苯基环己烯5种挥发性有机物（VOCs）的分析方法。选择聚二甲基硅氧烷（PDMS）作为萃取涂层,优化了SPME的萃取条件,包括平衡时间、萃取时间、萃取温度、顶空体积、离子强度、搅拌速度、解吸温度和时间以及GC—MS仪器条件。对于甲苯、4-乙烯基环己烯、苯乙烯、萘和1-苯基环己烯方法线性范围分别为0．087～870、3．32～3320、2．28～2280、0．015～150和0．050～50．0ng／g;检出限分别为0．005、0．042、0．670、0．008和0．011ng／g。实际样品加标回收率在80．1％～122％之间,RSD在0．8％～8．6％之间。方法符合纺织品中痕量VOCs的快速分析要求。