小球藻生长因子关键挥发性风味物质研究

为确定小球藻生长因子的风味特征,比较顶空⁃固相微萃取(headspace⁃solid phase microextraction,HS⁃SPME)和溶剂辅助风味蒸发(solvent⁃assisted flavor evaporation,SAFE)对挥发性风味物质的提取效果,结合气相色谱⁃质谱联用(gas chromatography⁃mass spectrometry,GC⁃MS),对小球藻生长因子液挥发性风味物质进行鉴定;并在此基础上采用气相色谱⁃嗅闻⁃质谱联用(gas chromatography⁃olfactory⁃mass spectrometry,GC⁃O⁃MS),结合相对气味活度值(relative odor activity value,ROAV)对小球藻生长因子中关键挥发性风味物质进行研究。结果表明:与SAFE相比,HS⁃SPME提取的挥发性风味物质种类更多,相对含量更高,鉴定出50种成分,主要为醇类、酮类、杂环类及醛类等;GC⁃O⁃MS结合ROAV筛选出5种关键风味物质,分别为2⁃庚酮、2,4,5⁃三甲基恶唑、噻唑、二甲基二硫醚和2⁃乙基己醇。

白花蛇舌草中脂溶性化学成分的GC⁃MS分析研究

目的:采用气质联用法分析研究白花蛇舌草中的脂溶性化学成分。方法:采用温浸溶剂提取法以石油醚作为溶剂提取白花蛇舌草中的脂溶性化合物,提取液经挥干后分别使用二氯甲烷和正己烷溶解,采用气相色谱⁃质谱联用技术结合质谱库检索系统对其脂溶性成分进行分离和鉴定,应用色谱峰面积归一化法计算各组分的相对百分含量。结果:通过分析结果对比得知采用二氯甲烷溶解的样品检测结果最好,共分离得到50个化学组分峰,并鉴定出其中的40个化学成分,占总量的87.35%。结论:分析得出白花蛇舌草中的脂溶性化学成分主要为十六烷酸、角鲨烯、顺式⁃异油酸、亚油酸;白花蛇舌草中脂溶性成分具有一定的药理活性;此分析方法方便快捷,准确度较高,可广泛使用于药用植物的脂溶性化学成分的分析与鉴定。

软儿梨果酒发酵过程中挥发性风味物质变化分析

软儿梨是西北地区特有的一种“冻果”产品,酸甜可口、果香浓郁,是酿造果酒的上乘原料。为明确果酒发酵过程中果香的保留情况,并探究发酵时间的延长对软儿梨果酒品质的影响,以青海省民和县软儿梨冻果为原料,基于带皮渣发酵工艺,先采用顶空固相微萃取(solid⁃phase microextraction,SPME),再结合气相色谱⁃质谱联用技术(gas chromatography⁃mass spectrometry,GC⁃MS)对原汁(0 d)、前发酵(7、14、28 d)、后发酵(100 d)3个不同时期样品中挥发性风味物质进行了动态跟踪分析,并结合相对气味活度值(relative odor activity value,ROAV)和主成分分析(principal component analysis,PCA)法分别探讨了软儿梨果酒原果香味保留情况和后发酵时间的延长对果酒风味的影响。结果显示:整个发酵过程共检出88种挥发性化合物,其中酯类33种、醇类29种、酸类6种、萜烯类7种以及13种其他类化合物,且风味物质的总含量随发酵的进行呈先上升后略有下降的趋势。ROAV结果表明:软儿梨原汁关键风味物质共8种,分别是丁酸乙酯、己酸乙酯、2⁃甲基丁酸乙酯、正辛醇、大马士酮、芳樟醇、丁香酚和癸醛;其中果香物质己酸乙酯、正辛醇、芳樟醇、丁香酚和大马士酮在果酒发酵中得到了很好的保留,是决定软儿梨果酒风味的关键物质。主成分分析表明:发酵初期主要的香气贡献物质是具有水果香的丁酸乙酯、3⁃羟基丁酸乙酯、2⁃甲基丁酸乙酯;发酵100 d时,乙酸乙酯、α⁃松油醇、柠檬烯和芳樟醇对香气贡献较大,这些香气化合物共同赋予软儿梨果酒幽香清雅、馥香浓郁的独特风味品质。研究获得了软儿梨果酒关键风味物质及其在不同发酵阶段特征风味物质的变化规律,可为研发高品质软儿梨果酒产品、改进软儿梨果酒发酵工艺提供理论支撑和参考。

Chemical composition and anti-MRSA activity of the essential oil from Chinese eaglewood

To analyze the constituents of essential oil from Chinese eaglewood [resinous wood of Aquilaria sinensis （Lour.） Gilg] and its anti-methicillin-resistant Staphylococcus aureus （MRSA） activity. The essential oil was extracted by water-steam distillation and analyzed by GC/MS method. The relative contents of the compounds were determined by normalization. The compounds were characterized by NIST05 and WILEY275L database matching and comparison of their MS spectra with those of literature data. Antibacterial activity of the oil was assayed by the filter paper disc agar diffusion method. The oil showed significant antibacterial activity against MRSA. Sixty-six chromatographic peaks were detected, among them thirty compounds comprising 59.80% of the total essential oil were characterized. Twenty-six compounds comprising 54.26% of the oil were identified as sesquiterpenes. β-Agarofuran （8.96%）, kusunol （7.82%）, （-）-jinkoh-eremol （5.04%）, agarospirol （4.53%）, baimuxifuranic acid （4.09%） were the major sesquiterpenes. Four nor-sesquiterpenes and some other sesquiterpenes, such as 10-epi-γ-eudesmol, α-agarofuran, epi-ligulyl oxide, etc. were detected in Chinese eaglewood oil for the first time. This is the first report about anti-MRSA activity of Chinese eaglewood oil from A. sinensis.

Chemical Compositions of Volatile Oil from Fruiting Body of Armillaria luteo-virens

The chemical compositions of volatile oil from fruiting body of Armillaria luteo-virens in Qinghai Province were firstly analyzed with GC-MS and its relevant compositions were detected by calculating chromatographic peak area with normalized method. 21 peaks were separated and 13 compositions were identified which were mainly unsaturated fatty acids, taking 97.1% of the total volatile oil.

不同产地3种苍术脂溶性成分的GC-MS分析

目的:比较不同产地苍术脂溶性成分在含量和组成上的差异,为苍术药材建立科学合理的产地鉴别和质量评价提供试验依据。方法:采用GC⁃MS法,DB⁃5 MS色谱柱(30 m×0.25 mm,0.25 mm),载气He,流速1.0 ml·min^(-1),进样口温度250℃,分流比20∶1,离子源温度230℃,电离方式EI;同时采用SPSS软件进行聚类分析。结果:不同产地3种苍术的脂溶性成分检测出20个共有成分,包括佛术烯、α⁃芹子烯、5⁃异丙烯基⁃3,6⁃二甲基⁃6⁃乙烯基⁃4,5,6,7⁃四氢⁃1⁃香豆酮和β⁃桉叶醇等。5⁃异丙烯基⁃3,6⁃二甲基⁃6⁃乙烯基⁃4,5,6,7⁃四氢⁃1⁃香豆酮相对含量最高,β⁃桉叶醇次之。茅苍术中α⁃芹子烯的相对含量明显低于北苍术和关苍术(P<0.05);关苍术和茅苍术中佛术烯含量均明显高于北苍术(P<0.01);5⁃异丙烯基⁃3,6⁃二甲基⁃6⁃乙烯基⁃4,5,6,7⁃四氢⁃1⁃香豆酮的相对含量北苍术和茅苍术之间有明显差异(P<0.05);北苍术和茅苍术的β⁃桉叶醇含量高于关苍术(P<0.01)。聚类分析将不同产地苍术划分为3个表征群,与茅苍术、北苍术和关苍术分类基本一致。结论:关苍术与茅苍术、北苍术特征图谱差异明显,通过不同产地不同品种4个成分分析并结合聚类分析,反映药材的道地性,为苍术药材质量标准优化、市场规范性以及临床疗效提供了科学的依据。

Supercritical Fluid Extraction of Essential Oil from Dry Rhizome of Ligusticum chuanxiong Hort and Their Characterization by GC/MS

Supercritical fluid extraction (SFE) of essential oil from dry rhizome ofLigusticum chuanxiong Hort was developed. GC/MS was used for the determination of the composition ofessential oil. Forty-four compounds were identified. The conventional extraction method wasconducted in parallel for comparison. The extracts were qualitatively compared by GC/MS. The yieldsof SFE and steam distillation-extraction were 4.16 % ( v/w) and 0.8 % ( v/w), respectively.Application of SFE of zessential oil from dry rhizome of Ligustiaan chuanxiong Hort was preferable.

GC-MS Analysis of Essential Oil Constituents from Rhizome and Root of Notopterygium forbesii

Aim To analyse the chemical constituents of the essential oil extracted from the rhizome and root of Notopterygium forbesii Boiss. and provide scientific basis for quality control. Methods The total essential oil was extracted by water-steam distillation and separated by capillary gas chromatography (GC). The components were determined by normalization method, and identified by GC-MS. Results GC-MS exhibited 217 peaks and 100 compounds were identified, accounting for 78.3% of the total essential oil. Conclu...

Analysis of Volatile Constituents in Lonicera japonica Thunb. from Different Origins by GC-MS

[Objective] This study aimed to analyze the volatile constituents in Lonicera japonica Thunb. from different origins. [Method] HP-5MS capillary columns were used and column temperature was controlled by a program. MS analysis was performed with EI and quadruple mass analyzer. The volatile constituents in L. japonica Thunb. were identified by NIST02 and Wiley275 libraries, and their relative contents were determined with chromatographic peak area normalization method. [Result] According to GC-MS total ion-current chromatograms, 35 volatile constituents were identified in L. japonica Thunb. from Guangxi Zhuang Autonomous Region, mainly including methyl linolenate, n-hexadecanoic acid and ζ-muurolene; 18 volatile constituents were identified in L. japonica Thunb. from Hunan Province, mainly including n-hexadecanoic acid, linoleic acid and α-curcumene. [Conclusion] Main volatile constituents in L. japonica Thunb. from two different origins varied significantly.

Analysis for the Volatile Secondary Metabolites of Mortierella alpina

[ Objective] The study was to investigate the volatile components of secondary metabolites from M. alpine producing arachidonic acid and explore the changes in its metabolic pathway. [ Method] The air above M. alpine broth was extracted by solid-phase microextraction（SPME） during the post-exponential phase of growth and analyzed by GC-MS. [Result] 13 compounds were identified, 12 of which were sesquiterpenes with C15H24 formula and accounting for 99.62% of the complete compounds. Thujopsene-（ 12）, α-Guaiene and Aristolene were three most sesquiterpenes accounting for 10.66%, 33.69% and 34.85% of total content respectively. It can be sufficiently certified that sesquiterpene metabolic pathway existing in M. alpine. [ Coclusion] Metabolic flux of sesquiterpene pathway increased to improve its mass accumulation, because one or several key enzyme genes mutation in isoprene or sesquiterpene pathway enhanced their activities during induction of mutation from initial strain.

GC-MS Analysis of Essential Oil Constituents from Buds of Tussilago farfara L.

Aim To analyse the constituents of the essential oils extracted from the buds of Tussilago farfara L. in the GAP Bases of Traditional Chinese Medical Materials and provide scientific basis for quality control. Methods The essential oils were extracted by water-steam distillation and separated by GC capillary column chromatography. The components were quantitatively determined by normalization, and identified by GC-MS. Results GC-MS exhibited 259 peaks and 65 compounds were identified, accounting for 84.62% of the total essential oil. Conclusion In the total essential oil contained in the buds of Tussilago farfara L., copaene （2.36%）, （ ＋ ） -Epi-bicyclosesquiphellandrene （ 3.91% ）, γ- elemene （2.18%）, fl-bisabolene （ 13.93% ）, spathulenol （ 3.44% ） as the sesquiterpenes and its derivatives, and 1-undecene （4.83%）, （ E）-cycloundecene （8.49%）, bicycle [ 10. 1.0] tridec-l-ene （ 1. 45% ）, 1-tridecene （3.44%）, （Z）-7,11-dimethyl-3-methylene-1,6,10-dodecatriene （2.66%）, 1- pentadecene （4.57%）, [ 1R-（ 1R^＊, 4Z, 9S^＊ ） ]-4,11,11-trimethyl-8-methylene-bicyclo [ 7.2.0] undec-4-ene （ 1.03% ）, 6,6-dimethyl-2-methylene-7-（ 3-oxobutylidene ）-oxepan-3-ylmethyl acetic acid ester （2.02%）, 1, E-11, Z-13-heptadecatriene （ 3.72% ）, （ Z, Z, Z） -9,12,15-octadecatrien-l-ol （ 1.85% ）, 3,7,11-trimethyl-dodeca-2,4,6,10-tetraenal （ 1.31% ）, n-hexadecanoic acid （ 3.12% ） , （Z, Z） -9,12-octadecadienoic acid （2.26%）, （ Z, Z, Z） -9,12,15-octadecatrienoic acid methyl ester （ 1.12% ） , heneicosane （ 1.82% ）, and pentacosane （ 1.03% ） are the main components.

GC-MS Analysis of Essential Oil Constituents from Rhizome and Root of Notopterygium incisum

Aim To analyse the chemical constituents of the essential oil extracted from the rhizome and root of Notopterygium incisum Ting ex H.T. Chang, providing scientific basis for quality control. Methods The total essential oil was extracted by water-steam distillation and separated by capillary gas chromatography （GC）. The components were determined by normalization method, and identified by GC-MS. Results GC-MS exhibited 242 peaks and 83 compounds were identified, accounting for 75.77% of the total essential oil. Conclusion In the total essential oil of the rhizome and root of N. incisum, monoterpenes and sesquiterpenes accounted for 13.63% and 67.93%, respectively, in which （ 1S）-β-pinene （ 1.67% ）, 3-carene （ 1.05% ）, limonene （ 1.22% ）, and 1S-endo-bornyl acetate （ 1.68% ） as the monoterpenes and its derivatives, and （ ＋ ） -β-elemene （6.78%）, sativene （1.54%）, α-caryophyllene （2.64%）, germacrene D （1.67%）, eudesma-4 （ 14 ）, ll-diene （2.36%）, α-selinene （2.42%）, δ-cadinene （ 1.55% ）, 3,7,11-trimethyl-2,6,10-dodecatrien-1-ol （1.03%）, （ ＋ ）-elemol （5.18%）, （-）-spathulenol （1.40%）, guaiol （3.81%）, dehydroxy-isocalamendiol （ 1.06% ）, γ-eudesmol （ 1.05% ）, α-eudesmol （7.97%）, bulnesol （3.09%）, and carotol （2. 30% ） as the sesquiterpenes and its derivatives were main components. In addition, isopropyl transcinnamate was the maximum compound （ 11.3% ） of the total essential oil.

Leaf Volatiles Induced by Mechanical Damage from Diverse Taxonomic Tree Species

Plant volatiles induced by wounding play key roles in plant-insect and plant-plant interactions. To deeply understand the mechanism of their induction by wounding and their functions in interplant communications, four diverse tree species: ashleaf maples ( Acer negundo L.), hankow willow (Salix matsudana Koidz.), Chinese white poplar ( Populus tomentosa Carr.) and poplar opera 8277 (P. simonii x P. pyramibalis cv.), were used as materials. The blends of volatiles collected after damage were detected with GCMS. Most of the induced compounds reach high concentrations in 5 h. They are acyclic monoterpenes, fatty acid derivatives, and aromatic compounds. To authors' knowledge, dimethyl adipate, diisobutyl succinate and benthothiazole have never been reported in previous herbivore insect-plant systems, After being damaged 2 h, green leaf volatiles were released in large amount. The repellents were detected in higher concentration after 24 h. The time of releasing is different within different species, but many kinds of volatiles widely existed in different trees. There were some difference among species. Health ashleaf maple released more terpenoids, but poplars and willow produced more aromatic compounds.

Analysis of Active Components of Hexane Extractives of Morus alba Leaves

[Objective]The aim was to explore the active compound of Morus alba leaves with the analysis of active components of hexane extractives of M.alba leaves.[Method]Antibacterial assays of hexane extractives of M.alba leaves were done and the volatile components of hexane extractives of M.alba leaves with the strongest antibacterial activity were analyzed by gas chromatography-mass spectrometry（GC-MS）.[Result]The results of inhibitory effect of hexane extractives of M.alba leaves on Staphylococcus aureus and Escherichia coli showed that hexane extractives of M.alba leaves collected in June,July and August had antibacterial activity against S.aureus and had no antibacterial effect against E.coli.Furthermore,hexane extractives of M.alba leaves collected in June had the strongest antibacterial activity against S.aureus（inhibition diameter 10.95 mm）.The hexane extractives of M.alba leaves collected in June was analyzed by GC-MS,the main volatile components were tetradecane（16.76%）,dodecane（13.20%）,diisobutyl phthalate（10.26%）,decane（9.10%）,hexadecane（8.71%）,linolenyl alcohol（7.25%）,octadecane（5.88%）,eicosane（3.26%）,dibutyl phthalate（2.59%）.[Conclusion]Linolenyl alcohol was the potential antibacterial compound.

Composition of Essential Oils of Morus alba Leaves and Chamaecyparis pisifera Outer Heartwood

[Objective] The aim was to explore the composition of essential oils of Morus alba leaves and Chamaecyparis pisifera outer heartwood. [Method] The essential oils of M. alba leaves and C. pisifera outer heartwood were analyzed by gas chromatography-mass spectrometry,respectively. [Result] Alcohols [phytol （59.47%,extracted 3 h for M. alba leaves）,α-cadinol （38.77%,extracted 6 h for C. pisifera outer heartwood）] were their first principal volatile components. Phytol was usually used as pharmaceutical raw material and α-cadinol was a kind of active organic compound with antibacterial function. [Conclusion] The essential oils of M. alba leaves and C. pisifera outer heartwood with hydrodistillation have medicinal value.

GC-MS Analysis of Essential oil and n-Hexane Extract from Moso Bamboo

[Objective] This study aimed to analyze the chemical composition and yield of essential oil and n-hexane extract from moso bamboo to find active compounds with potential value. [Method] Essential oil and n-hexane extract were respectively extracted from moso bamboo of four different ages by using hydrodistillation and ultrasonic-assisted extraction with n-hexane, and analyzed with gas chromatography/mass spectrometry （GC/MS）. [Result] The results show that cedrol （46.39%） is the first principal volatile component in essential oil of the middle stem of 7-year old moso bamboo; dibutyl phthalate （59.46%） is the first principal volatile component in n-hexane extract of the middle stem of 3-year old moso bamboo; yield of n-hexane extract is higher than that of essential oil from moso bamboo. [Conclusion] Cedrol is an active compound with potential value.

Determination of 10 Pyrethroids Pesticide Residues in Rice by GC-MS-MS

[Objective] A method was developed for the determination of 10 pyrethroids pesticide residues in rice by GC-MS-MS. [Method] Pyrethroids were extracted with acetonitrile, followed by a salting-out step with anhydrous magnesium sulfate and sodium chloride, cleaned up by florisil solid phase extraction （SPE） cartridge, and determined by multiple reaction monitoring mode. [Result] The method showed good linearity over the range of 0.010-0.500 mg/L for 10 pyrethroid pesticide with correlation coefficients over 0.99. The detection limits were 0.005 -0.010 mg/kg. The method was validated by analyzing samples spiked with 0.05, 0.10, 0.20 mg/kg of 10 pyrethroid pesticides, respectively. The average recoveries in rice ranged from 75.0-115.5%, and the relative standard deviations （RSD） were between 3.9%-6.9%. [Conclusion] The method is easy, accurate and reliable, which can meet the requirement for the simultaneous determination and confirmation of pyrethroid pesticide residues in rice.

Pyrolysis-Gas Chromatography/Mass Spectrometry for Microstructure and Pyrolysis Pathway of Polyester-Polyether Multiblock Copolymer

The composition and sequence distribution of monomeric units in polyester polyether multiblock copolymer were studied by pyrolysis? gas chromatography (PGC) and pyrolysis gas chromatography/mass spectrometry (PGC/MS). PGC was applied to study the F t curve of the multiblock copolymer and PGC/MS was used to separate and identify the pyrolyzates. DTA experiment was used to study the decomposition temperature. The results show that the beginning point of elastomer’s decomposition was about 300?℃ and the decomposition temperature of most of the sample was 550?℃. Many pyrolyzates were produced because of the breaking of weak bonds in the sample. The possible microstructure was verified and the pyrolysis pathway of the copolymer was investigated.

Analysis of Volatile Constituents in Bamboo Leaves Using HS-GC/MS

[Objective] This study aimed to analyze the volatile constituents in bamboo leaves. [Method] The volatile compositions in bamboo leaves were analyzed by headspace-gas chromatography-mass spectrometry （HS-GC/MS）, and identified by searching their mass spectra in NIST database. The relative percentages of them were calculated by the GC peak areas. [Result] Fifty-three chemical constituents in bamboo leaves were separated. Among them, the main components were alcohols, ketones and aldehydes, and these compounds contained unsaturated bonds. [Con- clusion] HS-GC/MS was simple and less sample-demanding and can be used for rapid analysis of volatile constituents in bamboo leaves and provide scientific basis for further research and development of bamboo leaves.

Prediction of gastric cancer metastasis through urinary metabolomic investigation using GC/MS

AIM:To gain new insights into tumor metabolism and to identify possible biomarkers with potential diagnostic values to predict tumor metastasis.METHODS:Human gastric cancer SGC-7901 cells were implanted into 24 severe combined immune deficiency (SCID) mice,which were randomly divided into metastasis group (n=8),non-metastasis group (n=8),and normal group (n=8).Urinary metabolomic information was obtained by gas chromatography/mass spectrometry (GC/MS).RESULTS:There were significant metabolic differences among the three groups (t test,P < 0.05).Ten selected metabolites were different between normal and cancer groups (non-metastasis and metastasis groups),and seven metabolites were also different between non-metastasis and metastasis groups.Two diagnostic models for gastric cancer and metastasis were constructed respectively by the principal component analysis (PCA).These PCA models were confirmed by corresponding receiver operating characteristic analysis (area under the curve=1.00).CONCLUSION:The urinary metabolomic profile is different,and the selected metabolites might be instructive to clinical diagnosis or screening metastasis for gastric cancer.