固相微萃取-气相色谱/质谱法分析白胡椒粉的风味成分

采用固相微萃取采集白胡椒粉的挥发性成分,用色谱／质谱法分析鉴定,并用总离子流色谱峰的峰面积进行归一化定量分析其风味成分,鉴定出石竹烯（20．88％）,1-甲氧基-4-（2-丙烯基）苯（20．57％）,β-水芹烯（15．27％）,3-蒈烯（14．56％）,1-甲基-3-异丙基苯（3．62％）,β-蒎烯（2．69％）,芳樟醇（2．69％）,香叶烯（2．36％）,墨榄香烯（2．10％）,胡椒烯（1．32％）等48种化合物。     

芹菜籽香气成分研究

采用固相微萃取法萃取黑龙江产芹菜籽香气成分,然后用GC—MS进行成分分析,并与水蒸气蒸馏法获得的精油成分进行比较．用CAR on PDMS萃取柱进行顶空固相微萃取时,共检测出26种成分,鉴定出占总成份89．650％的20种成分,主要成分为柠檬烯（35．980％）,β-月桂烯（20．500％）,β-蛇床烯（16．160％）,正戊基苯（5．295％）,β-蒎烯（3．412％）,α-蛇床烯（3．293％）．水蒸汽蒸馏法提取芹菜籽,以1．18％产率获得精油,共检测出23个成分,鉴定出占总精油91．375％的18种成分,主要成分为柠檬烯（31．149％）,β-蛇床烯（22．281％）,对甲苯基异戊酸酯（14．944％）,α-2-丙烯基苯甲醇（9．872％）,β-月桂烯（4．324％）和α-蛇床烯（4．322％）．     

萃取淫羊藿挥发油的实验与分析

报道了用正交实验法研究超临界萃取淫羊藿挥发性成分的条件;结果显示最佳萃取条件为萃取压力30 MPa,萃取温度40℃,萃取时间1 h。按对结果影响大小依次排列为:萃取压力→萃取温度→萃取时间,在最佳条件下萃取挥发油,收率为2.7%;并用气相色谱-质谱联用技术分析了淫羊藿挥发油的化学成分,从中确认出43种化学成分,用峰面积归一化法通过化学工作站数据处理系统得出各化学成分在挥发油中的质量分数;其中主要成分为薄荷醇、1,2-二甲氧基-4-(2-丙烯基)-苯、5-(1-丙烯基)-1,3-苯并间二氧杂环戊烯、3,5-二甲氧基-甲苯、冰片、十五(碳)烷、1,2,3-三甲氧基-5-甲苯、外-葑醇、2,6,6-三甲基-2,4-环庚二烯-1-酮、2-莰酮等。     

莽吉柿中几种双苯吡酮和蒽醌类成分的分离与鉴定

对莽吉柿(Pericarpium Garciniae Mangostanae)85%乙醇提取物进一步分离,得到8个双苯吡酮类化合物和1个蒽酮类化合物,经理化性质和NMR及MS谱学数据鉴定分别为α-倒捻子素-3,6-二乙酸酯（α-mangostin-3,6-diyl diacetate,Ⅰ）、1,5,8-三羟基-3-甲氧基-2,4-双-（3-甲基丁-2-烯）双苯吡酮（8-hydroxycudraxanthone G,Ⅱ）、1,3-二羟基-6,7-二甲氧基-2,8-双-（3-甲基丁-2-烯基）双苯吡酮（Cowaxanthone B,Ⅲ）、1,6-二羟基-3,5-二甲氧基-2-（3-甲基丁-2-烯基）双苯吡酮（Cowaxanthone A,Ⅳ）、1,5-二羟基-4-（3-甲基丁-2-烯基）-6′,6′-二甲基吡喃[2′,3′:3,2]双苯吡酮（trapezifolixanthone,Ⅴ）、1,6-二羟基-6′,6′-二甲基吡喃[2′,3′:7,8]-6″,6″-二甲基吡喃[2″,3″:3,2-]双苯吡酮（brasilixanthone B,Ⅵ）、1,3,5-三羟基-2-（3-甲基丁-2-烯）-4-（1,1-二甲基-2-烯丙基）双苯吡酮（Allanxanthone A,Ⅶ）、1,3,8-三羟基-5-甲氧基-2,4-双-（3-甲基丁-2-烯）双苯吡酮(2,4-di-(3-methylbut-2-enyl)-1,3,8-trihydroxy-5-methoxyxanthone,Ⅷ)、1,4,8-三羟基-6-甲基-3-甲氧基-9,10-蒽酮(1,4,8-trihydroxy-6-methyl-3-methoxy- 9,10-anthraquinone, Ⅸ）。 其中化合物Ⅰ、Ⅴ、Ⅵ、Ⅶ、Ⅸ为首次从藤黄属植物中分离得到,化合物Ⅱ、Ⅲ、Ⅳ、Ⅷ为首次从该植物中分离得到。     

一种合成娃儿藤碱重要中间体的新方法

以二乙酸碘苯（PIDA,2）为催化剂,分别由3,4-二甲氧基-α-（3,4-二甲氧苯基）一肉桂酸（5a）和（Z-2-（3,4-二甲氧苯基）-3-（3,4-二甲氧苯基）-丙烯腈（5b）为原料,合成了相应的2,3,6,7-四甲氧基-9-羧基菲（6a）和2,3,6,7-四甲氧基-9-氰基菲（6b）,经^1H NMR测试技术表征为关环产物,产率分别为65．83％和64．76％。     

大叶桉化学成分的研究 - 大叶桉酚乙和其它成分的分离和鉴定

从大叶桉叶的乙醇提取物中分离并鉴定出九种已知成分:5-羟基-4',7-二甲氧基6,8-二甲基黄酮,4',5-二羟基-7-甲氧基6,8-二甲基黄酮,3β-羟基-乌索-11-烯-28,13β-内酯,13β-乙酰氧基-乌索-11-烯-28,13β-内酯;3β,28-二羟基-乌索-12-烯,β-谷甾醇,2-甲基5,7-二羟基-苯骈吡喃酮-7β-葡萄糖苷,正卅烷醇和正卅烷酸,另外,分得一种新的酰基间苯三酚类成分,命名为大叶桉酚乙,其结构为2-甲氧基-4,6-二羟基异丁酰基苯,并进行化学合成确证,大叶桉酚乙在管碟法中对金黄色葡萄球菌和枯草杆菌有抑菌作用。     

茵陈挥发油的超临界CO2萃取法与水蒸气蒸馏法提取的比较

采用超临界CO2萃取法与水蒸气蒸馏法从菌陈中提取挥发油，用GC－MS法测定其化学成分和相对含量，对两种提取方法所得的挥发油进行比较，水蒸气蒸馏法提取菌陈挥发油的产率为0．03％（w），主要成分为匙叶桉油烯醇、吉玛烯D、反式－石竹烯、2，4－戊二炔苯、β－金石欢烯等；超临界CO2萃取法提取的产率为0．15％(w)，主要成分为百里酚、β－红没药烯、2－异丙基－4－甲基－1－甲氧基苯、异百里酚、2－特丁基－4－（2，4，4－三甲基戊基）苯酚、β－杜松烯等。     

雪香兰挥发油化学成分的研究

采用水蒸汽蒸馏法从雪香兰中提取挥发油,利用GC—Ms联用仅对其化学成分进行分析,用归一化法计算各组分的相对百分含量。经毛细管气相色谱分离出33个峰,共确认了其中31种成分,占总油量的98％。其主要成分是斯巴醇、α-石竹烯、1-乙烯基-1-甲基-2-（1-甲基乙烯基）4-（1-甲基二乙烯基）-环己烷、3,7,11-三甲基．1,6,10-十二碳三烯-3-醇等。     

桉树叶挥发油化学成分的研究

采用毛细管气相色谱-质谱（CGC-MS）联用技术对桉树叶挥发油的化学成分进行研究,经毛细管气相色谱分离出30个峰,共确认了其中21种成分,占总油量的97．57％。其主要成分是按油精、3,7,7-三甲基-二环[4．1．0]庚2-烯、α,α,4-三甲基-3-环已烯-1-甲醇、喇叭茶醇等。     

新型苯并二氢呋喃合二酮酸类化合物的合成及其与整合酶分子对接研究

以阿魏酸甲酯为原料,通过氧化偶联构建2-芳基苯并二氢呋喃骨架,再经傅克酰基化和酯缩合反应依次制得(E)-3-［2-(4-羟基-3-甲氧基-5-乙酰基)苯基-3-甲氧羰基-7-甲氧基-2,3-二氢苯［b］并呋喃-5-基］丙烯酸甲酯（3）和(E)-3-［2-(4-羟基-3-甲氧基-5-甲氧羰基乙酰基)苯基-3-甲氧羰基-7-甲氧基-2,3二氢苯并［b］呋喃-5-基］丙烯酸甲酯（4）; 4经水解反应合成3-【2-羟基-3-甲氧基-5-｛5-［2-（甲氧基羰基）乙烯基］-7-甲氧基-3-甲氧羰基-2,3-二氢苯并［b］呋喃-2-｝基】苯基-3-氧丙酸（5）,化合物3~5未见文献报道,其结构经¹H NMR, ¹³C NMR和MS(ESI)表征。采用分子对接软件Autodock vina对化合物2~5与HIV-1整合酶核心部位高度同源的PFV IN（PDB: 3L2V）进行对接,计算结果显示该类化合物能与整合酶形成稳定的复合物,具有1,3-二酮基团的化合物3, 4和5能与整合酶中金属离子产生螯合作用,其中化合物5的结合作用最强。     

Rapid determination of volatile constituents in safflower by microwave distillation and simultaneous solid-phase microextraction coupled with gas chromatography-mass spectrometry

In this paper, microwave distillation and solid-phase microextraction coupled with gas chromatography-mass spectrometry (MD-SPME/GC-MS) was developed for the analysis of essential components in safflower. Using the MD-SPME technique, the isolation, extraction and concentration of volatile compounds in safflower were carried out in only one step. Some parameters affecting the extraction efficiency such as SPME fiber coating, microwave power, irradiation time and the volume of water added were optimized. The optimal experiment parameters obtained were: 65 microm CW/DVB SPME fiber, a microwave power of 400 W, an irradiation time of 3 min and water volume of 1 mL. The proposed method has been compared with conventional steam distillation (SD) for extraction of essential oil compounds in safflower. Using MD-SPME followed by GC-MS, 32 compounds in safflower were separated and identified, which mainly included paeonol, alpha-asarone, beta-asarone, 1-methyl-4-(2-propenyl)-benzene and diethenyl-benzene, whereas only 18 compounds were separated and identified by conventional SD followed by GC-MS. The relative standard deviation (R.S.D.) values of less than 10% show that the proposed method has good reproducibility. The results show that MD-SPME/GC-MS is a simple, rapid, effective method for the analysis of volatile oil components in safflower.     

GC-MS法测定大蒜中的挥发性物质

大蒜(AlliumsatiuvmL.)是多年生草本百合科植物大蒜的鳞茎,按皮的颜色不同可分为紫皮蒜和白皮蒜两种。大蒜原产于意大利的西西里岛,约在两千多年前传入我国。大蒜不仅是极佳的调味食品,而且还有很好的药用功能。近年来,科学家研究证明,大蒜是一种健康食品,有助人体防病保健、延年益寿,是药食兼优的佳品,对人体具有多种药用价值。大蒜具有一种强烈的蒜臭气味,这种特殊的气味由许多复杂的硫化物组成。这类有机硫化物可促进消化,健胃整肠,强化抗菌作用,消肿止痛,改善机体机能的功能,大蒜中还含有乙烷硫代磺酸乙酯和二烯丙基三硫化物等,能阻断强烈致癌物质亚硝胺类在胃部的形成和积累,可预防胃癌、食道癌、肝癌、鼻咽癌的发生。本试验采用"同时蒸馏-萃取方法"(simultaneousdistillationandextraction,SDE)提取白皮和紫皮大蒜的挥发性成分,经GC-MS分析,确定了化合物的化学组成和相对百分含量。     

Essential oil from the leaves of Annona vepretorum: chemical composition and bioactivity

The essential oil from the leaves of Annona vepretorun was obtained by hydrodistillation using a Clevenger-type apparatus and analyzed by GC-MS and GC-FID. Eighteen compounds representing 98.1% of the crude essential oil were identified. The major compounds identified were bicyclogermacrene (43.7%), spathulenol (11.4%), alpha-felandrene (10.0%), alpha-pinene (7.1%), (E)-beta-ocimene (6.8%), germacrene D (5.8%), and p-cymene (4.2%). The trypanocidal activity against Trypanosoma cruzi epimastigote forms, as well as, the antimicrobial and antioxidant proprieties was investigated. The essential oil showed a potent trypanocidal activity with IC50 value of 31.9 +/-1.3 microg x mL(-1). For antimicrobial activity, the best result was observed against Candida tropicalis with a MIC value of 100 microg x mL(-1). For antioxidant capacity the essential oil showed weak activity.     

Composition and enantiomeric analysis of the essential oil of the fruits and the leaves of Pistacia vera from Greece

The essential oils of the fruits and the leaves of pistachio (Pistacia vera L.) were analyzed by GC and GC/MS. Fresh unripe pistachio fruits were richer in essential oil (0.5%, w/w) than the leaves (0.1%, w/w). Twenty one compounds were identified in the essential oil of the fruits and the major components were (+)-alpha-pinene (54.6%) and terpinolene (31.2%). The enantiomeric ratio of the major constituents of the essential oil of the fruits was determined using chiral GC/MS and it was found that the (+)/(-)-alpha-pinene ratio was 99.5:0.5, (+)/(-)-limonene 80:20, (+)/(-)-beta-pinene 96:4, and (+)/(-)-alpha-terpineol 0:100. Thirty three compounds were identified in the essential oil of the leaves and the major components were found to be alpha-pinene (30.0%), terpinolene (17.6%) and bornyl acetate (11.3%).     

Chemical composition, antimicrobial and antioxidant activities of the essential oil of Tibetan herbal medicine Dracocephalum heterophyllum Benth

The essential oil of Tibetan medicine Dracocephalum heterophyllum Benth was obtained by hydrodistillation with a 0.7% (v/w) yield. The chemical composition of the essential oil was analyzed by gas chromatography-mass spectral (GC-MS). Eighty-three compounds, constituting about 89.83% of the total oil, were identified. The main compound in the oil were Cineole (14.89%), trans-nerolido (7.10%), 1-m-ethyl-2-(1-methylethyl)-benzene (4.42%), Germacrene-D (4.84%), Decahydro-1,1,4,7-tetramethyl-4aH-cycloprop[e]azulen-4a-ol (4.94%), p-menth-1-en-4-ol,acetate (4.34%), 4-methyl-1-(1-methylethyl)-3-cyclohexen-1-ol (4.10%). The antimicrobial activity of the oil was evaluated against nine bacterial, one yeast, and three fungi. The antimicrobial test result showed that the essential oil strongly inhibited the growth of test microorganisms studied. The maximal inhibition zones and MIC values for bacterial, yeast and fungi strain were in the range of 18-25 mm and 0.039-0.156 mg mL(-1); *20 mm, and 0.156 mg mL(-1); 8-24 mm and 0.313-2.5 mg mL(-1); respectively. The antioxidant activity of the oil was determined by the malonyldialdehyde (MDA) test, measuring the MDA concentration in mouse liver cell microsomal after induced lipid peroxidation using FeSO(4) and ascorbic acid, The inhibition of lipid peroxidation was 59.3% with a concentration of 0.5 mg mL(-1). Result presented here may suggest that the essential oil of D. heterophyllum posses antimicrobial and antioxidant properties, and therefore, they can be one of new medicinal resources for antimicrobial agent and/or used as a natural preservative ingredient in food and cosmetics and pharmaceuticals industry.     

Chemical composition and antimicrobial activity of the essential oil of Anthemis altissima L. var. altissima

The essential oil obtained from the flowering parts of Anthemis altissima L. var. altissima was analysed by gas chromatography and gas chromatography mass spectroscopy. In this study, 34 compounds representing 98.76% of the essential oil were identified. The main components were α-terpineol (26.42%), β-pinene (9.23%), cis-chrysanthenyl acetate (6.30%), globulol (5.36%), n-tricosane (4.41%), terpinen-4-ol (4.08%) and 1,8 cineole (3.84%). Antibacterial activities of the essential oil and its two major components (α-terpineol and β-pinene) were determined using microdilution method against both Gram-positive (Staphylococcus aureus, Bacillus subtilis, Staphylococcus epidermidis) and Gram-negative (Escherichia coli, Pseudomonas aeruginosa, Klebsiella pneumoniae) bacteria. The essential oil showed a broad-spectrum antibacterial activity (MICs ranged from 3.13 to 6.25?μL?mL(-1)). It was found that α-terpineol with minimum inhibitory concentration (MIC) values of the range 0.87-1.56?μL?mL(-1) was a more potent antibacterial agent than β-pinene with MIC values of the range 1.56-6.25?μL?mL(-1). All of them, the essential oil, β-pinene and α-terpineol, were more effective against Gram-positive bacteria than Gram-negative ones.     

Chemical composition and antibacterial activity of the essential oil of Moroccan Juniperus phoenicea

The antibacterial activity of the essential oil from leaves of Juniperus phoenicea (Cupressaceae) and its chemical constituents were investigated in this study. The essential oil was obtained by hydro-distillation and analyzed by gas chromatography equipped with a flame ionisation detector (GC-FID), and gas chromatography coupled to a mass spectrometer (GC-MS). Sixty-three volatile compounds were identified representing 52 to 92% of the total oil compositions. The main monoterpenes were a-pinene (26.7-78.7%) and 6-3carene (7.6-15.4%). The antibacterial activity of J. phoenicea essential oil, when tested against both Gram-positive and Gram-negative bacteria, showed high activity against all bacteria tested, except Pseudomonas.     

Chemical composition and antioxidant activities of the essential oil from Nandina domestica fruits

The chemical composition and antioxidant activities of the essential oil from Nandina domestica fruits were studied for the first time. Twenty-two compounds, representing 82.79% of the oil, were identified from the oil. The major compounds were 3-hexen-1-ol (12.9%), linalool (12.3%), 2-methoxy-4-vinylphenol (9.9%), oleic acid (8.0%), furfural (5.8%) and 2,6-di-tert-butyl-4-methylphenol (5.7%). The antioxidant activities of the oil were evaluated using reducing power, metal chelating ability and scavenging capacity against 1,1-diphenyl-2-picrylhydrazyl (DPPH), 2,2′-azinobis-3-ethylbenzthiazoline-6-sulfonate (ABTS) and superoxide anion free radical. The oil exhibited significant antioxidant activities.     

Composition, antioxidant and antimicrobial activities of the leaf essential oil of Machilus japonica from Taiwan

The chemical composition, and antioxidant and antimicrobial activities of the essential oil isolated from the leaf of Machilus japonica from Taiwan have been investigated. The essential oil from the fresh leaves was isolated using hydrodistillation in a Clevenger-type apparatus, and characterized by GC-FID and GC-MS. A total of 97 compounds were identified, representing 100% of the oil. The main components identified were alpha-phellandrene (14.5%), alpha-pinene (12.8%), thymol (12.6%), beta-pinene (8.3%), alpha-terpineol (6.5%) and carvacrol (6.0%). The antioxidant activity of the oil was tested by the DPPH (2,2-diphenyl-1-picrylhydrazyl) free radical scavenging capability test. The results showed that the IC50 was 51.8 microg/mL. The antimicrobial activity of the oil was tested by the disc diffusion and micro-broth dilution methods against ten microbial species. The oil exhibited strong growth suppression against Gram-positive bacteria and yeast, with inhibition zones of 48-54 mm and MIC values of 16.12-32.25 microg/mL, respectively. For the antioxidant and antimicrobial activities of the oil, the active source compounds were determined to be thymol and carvacrol.