不同采摘时间干、鲜道真洛龙党参挥发油的GC-MS分析

研究不同采摘时间干、鲜道真洛龙党参挥发油成分的变化。采用水蒸气蒸馏的方法分别对干、鲜道真洛龙党参中的挥发油成分进行提取,提取物采用气相色谱-质谱联用技术(GC-MS)进行分析鉴定,以面积归一法计算各组分的相对百分含量。干道真洛龙党参挥发油主要成分为棕榈酸、亚油酸、肉豆蔻酸、棕榈酸甲酯、亚油酸甲酯和角鲨烯等。鲜道真洛龙党参挥发油主要成分为角鲨烯、亚油酸甲酯、棕榈酸、14-甲基十五烷酸甲酯和1-柠檬烯等。11月中旬采摘的干、鲜道真洛龙党参共有挥发油成分含量最高。干和鲜道真洛龙党参挥发油成分的种类差异不大,但含量差异较为明显。不同采摘时间干、鲜道真洛龙党参共有挥发油成分差异均不大,但其余挥发油成分差异明显。本研究首次对道真洛龙党参挥发油成分进行分析报道,以期为道真洛龙党参进一步开发研究提供参考。     

不同采摘时间干、鲜道真洛龙党参挥发油的GC-MS分析北大核心CSCD

研究不同采摘时间干、鲜道真洛龙党参挥发油成分的变化。采用水蒸气蒸馏的方法分别对干、鲜道真洛龙党参中的挥发油成分进行提取,提取物采用气相色谱-质谱联用技术(GC-MS)进行分析鉴定,以面积归一法计算各组分的相对百分含量。干道真洛龙党参挥发油主要成分为棕榈酸、亚油酸、肉豆蔻酸、棕榈酸甲酯、亚油酸甲酯和角鲨烯等。鲜道真洛龙党参挥发油主要成分为角鲨烯、亚油酸甲酯、棕榈酸、14-甲基十五烷酸甲酯和1-柠檬烯等。11月中旬采摘的干、鲜道真洛龙党参共有挥发油成分含量最高。干和鲜道真洛龙党参挥发油成分的种类差异不大,但含量差异较为明显。不同采摘时间干、鲜道真洛龙党参共有挥发油成分差异均不大,但其余挥发油成分差异明显。本研究首次对道真洛龙党参挥发油成分进行分析报道,以期为道真洛龙党参进一步开发研究提供参考。     

民族药木耳菜挥发油成分和脂溶性成分GC-MS分析

采用水蒸气蒸馏法和索氏提取法提取木耳菜挥发油和脂溶性成分,利用GC-MS技术鉴定挥发油和脂溶性成分。鉴定出47个挥发油成分和20个脂溶性成分。其挥发油成分主要有依兰烯(7.30%)、δ-杜松烯(6.85%)、氧化石竹烯(5.90%)、1,5,9-三甲基-12-(1-甲基乙基)-4,8,13-环戊二烯并环辛四烯-1,3-二醇(5.83%)等。脂溶性成分主要有8,11-十八碳二烯酸甲酯(16.09%)、棕榈酸甲酯(12.15%)、花生酸甲酯(7.06%)、亚麻酸甲酯(7.00%)等。     

缺萼枫香叶挥发油的化学成分研究

以水蒸气蒸馏法提取缺萼枫香叶中的挥发油,首次以气相色谱-质谱联用技术对其化学成分进行分离、鉴定,共分离出44个成分,鉴定了其中的29个成分,占挥发油总量的81.04%,主要成分为n-棕榈酸(27.03%)和9,12,15-十八酸(13.35%)。     

土茯苓挥发性成分研究

目的:研究土茯苓中的挥发性成分。方法:利用水蒸气蒸馏法提取土茯苓(Smilax glabraRoxb.)挥发油,用GC-MS进行测定,结合计算机检索技术对分离的化合物进行结构鉴定,应用色谱峰面积归一化法计算各成分的相对百分含量。结果:分离了40个化合物,鉴定出22个化学成分,占总挥发性成分的47.88%,其中相对百分含量大于1%的分别确定为棕榈酸17.87%,萜品烯-4-醇7.533%,亚油酸6.775%,正壬烷4.509%,8,11-十八碳二烯酸甲酯2.215%,α-雪松醇1.81%,甲基棕榈酯1.293%。结论:22个挥发性成分均为首次从该植物中得到。     

秦芄挥发性成分研究

目的:研究秦芄(Radix Centianae Macrophyllae)中的挥发性成分.方法:利用水蒸气蒸馏法提取秦芄挥发油,用GC/MS进行测定,结合计算机检索技术对分离的化合物进行结构鉴定,应用色谱峰面积归一化法计算各成分的相对百分含量.结果:分离出8个组分,鉴定出7个化学成分.检出率为91.40%.秦艽挥发性成分大于1%的分别确定为萜品烯-4-醇1.224%,(E,E)-2,4-癸二烯醛1.295%,棕榈酸乙酯32.009%,棕榈酸54.608%.结论:首次报道了用GU/NS对秦艽挥发性成分的研究,为该类植物的研究开发提供必要的试验数据.     

萼翅藤枝叶挥发油及其抗菌活性的研究

萼翅藤枝叶挥发油由GC/MS检测.树叶挥发油的52种成分中,氧化石竹烯(13.79%)、棕榈酸(11.91%)和β-石竹烯(10.45%)是主要成分.同时,树枝挥发油中的10种成分占总量的99.99%,其中主要的化学成分为棕榈酸(59.18%),亚油酸(12.70%)和邻苯二甲酸丁辛酯(8.21%).用滤纸扩散法,分别测定了枝、叶挥发油对8种微生物的抑制效果.枝、叶挥发油均具有很强的抗菌效果,并且抗细菌活性优于抗真菌活性.叶挥发油比枝挥发油具有更广谱的抑菌效果,且对所试的大多数菌株都具有更高的活性.     

三七叶挥发油的化学成分分析

采用自制的同时蒸馏萃取装置提取文山三七叶的挥发油成分,然后用GC-MS法分析并鉴定了各组成及质量分数。挥发油中共鉴定出69个成分,占总峰面积的73．09。主要挥发性成分及面积归一化法测得含量为棕榈酸（27．36％）、亚油酸（10．68％）、亚麻醇（8．60％）、2,6-二叔丁基对甲基苯酚（4．67％）、1,3-环辛二烯（3．90％）、5．十八炔（2．31％）、植物醇（1．92％）、六氢化法尼基丙酮（1．39％）、斯巴醇（1．35％）等。     

野生蜂窝草籽中挥发油的研究

采用水蒸气蒸馏法从野生蜂窝草籽中提取挥发油,利用气相色谱-质谱联用技术对其挥发油中的化学组分进行分离和结构鉴定,运用气相色谱面积归一化法确定各个组分的相对百分含量。从蜂窝草籽挥发油中鉴出56种成分,主要组分是油酸(12.57%),棕榈酸(10.36%),1-辛烯-3-醇(7.96%),石竹烯(5.98%),2,4,6-三甲基-1,3,6-庚三烯(5.63%)等。对蜂窝草籽挥发油进行了抗氧化实验和抗菌实验,结果表明蜂窝草籽挥发油对.OH有明显的清除作用,蜂窝草籽挥发油对实验菌株均有明显的抑制和灭活作用特别是对大肠杆菌ATCC25922株和肠炎沙门菌50040株的抗菌活性表现得更为显著。     

山石榴果实挥发油的化学成分分析

采用超临界CO2提取山石榴果实挥发油,并利用GC-MS联用技术分析挥发油的化学组成。从山石榴果实挥发油中分离、鉴定出33个化合物,占挥发油总量的89.43%。挥发油主要由各种酯、脂肪酸成分组成,含量较高的成分是11,14-二十碳二烯酸甲酯(11,14-eicosadienoic acid,methyl ester,42.49%),棕榈酸(pal mitic acid,15.34%),硬脂酸(stearic acid,10.54%),肉豆蔻酸(myristic acid,6.26%),十六酸乙酯(hexa-decanoic acid,ethyl ester,5.84%)。     

Pheromone biosynthetic pathways in the moths Helicoverpa zea and Helicoverpa assulta

Sex pheromones of many Lepidopteran species have relatively simple structures consisting of a hydrocarbon chain with a functional group and usually one to several double bonds. The sex pheromones are usually derived from fatty acids through a specific biosynthetic pathway. We investigated the incorporation of deuterium-labeled palmitic and stearic acid precursors into pheromone components of Helicoverpa zea and Helicoverpa assulta. The major pheromone component for H. zea is (Z)11-hexadecenal (Z11-16:Ald) while H. assulta utilizes (Z)9-hexadecenal (Z9-16:Ald). We found that H. zea uses palmitic acid to form Z11-16:Ald via delta 11 desaturation and reduction, but also requires stearic acid to biosynthesize the minor pheromone components Z9-16:Ald and Z7-16:Ald. The Z9-16:Ald is produced by delta 11 desaturation of stearic acid followed by one round of chain-shortening and reduction to the aldehyde. The Z7-16:Ald is produced by delta 9 desaturation of stearic acid followed by one round of chain-shortening and reduction to the aldehyde. H. assulta uses palmitic acid as a substrate to form Z9-16:Ald, Z11-16:Ald and 16:Ald. The amount of labeling indicated that the delta 9 desaturase is the major desaturase present in the pheromone gland cells of H. assulta; whereas, the delta 11 desaturase is the major desaturase in pheromone glands of H. zea. It also appears that H. assulta lacks chain-shortening enzymes since stearic acid did not label any of the 16-carbon aldehydes.     

维药香蜂花挥发油的GC-MS分析

结合气相色谱-质谱联用技术和保留指数对维医常用药材香蜂花挥发油提取物进行了分析.从该挥发油中共准确鉴定出28个化合物,占提取物总量的99.02％.结果发现,主要成分有(E)-3,7-dimethyl-2,6-octadien-1-ol acetate( 26.48％)、(Z)-citral(15.46％)、(E)-nerol(14.51％)、(E)-citral(14.43％)、isoanisole (7.88％)、palmitic acid (6.93％)和(Z)-nerol (2.56％),多为单萜和倍半萜类成分,为维药香蜂花的质量标准制定提供了科学依据.     

杨梅核脂肪酸及蜡质成分分析

采用GC-MS联用技术,对杨梅(Myrica rubra)核中的脂肪酸及蜡质成分进行了分析.结果表明,杨梅核中脂肪酸和蜡质的总含量为31.10%,其中含有8种脂肪酸和3种长链烷烃,主要为棕榈酸(C16:0)28.22%、亚油酸(C182)14.4%、顺式-油酸(C18:1)25.74%、芥酸(C22:1)15.68%、十七烷5.2%、十八烷5.87%和十九烷4.71%,是一种优质和价廉的脂肪酸来源.     

Comparative study of sex pheromone composition and biosynthesis in Helicoverpa armigera, H. assulta and their hybrid

Two Helicoverpa species, H. armigera and H. assulta use (Z)-11-hexadecenal and (Z)-9-hexadecenal as their sex attractant pheromone components but in opposite ratios. Since both female and male interspecific hybrids produced by female H. assulta and male H. armigera have been obtained in our laboratory, we can make a comparative study of sex pheromone composition and biosynthesis in the two species and their hybrid. With GC and GC-MS analyses using single gland extracts, the ratio of (Z)-9-hexadecenal to (Z)-11-hexadecenal was determined as 2.1:100 in H. armigera, and 1739:100 in H. assulta. The hybrid has a ratio of 4.0: 100, which is closer to that of H. armigera, but significantly different from H. armigera. We investigated pheromone biosynthesis with labeling experiments, using various fatty acid precursors in H. armigera, H. assulta and the hybrid. In H. armigera, (Z)-11-hexadecenal is produced by delta11 desaturation of palmitic acid, followed by reduction and terminal oxidation; (Z)-9-hexadecenal results from delta11 desaturation of stearic acid, followed by one cycle of chain shortening, reduction and terminal oxidation. delta11 desaturase is the unique desaturase for the production of the two pheromone components. In our Chinese strain of H. assulta, palmitic acid is used as the substrate to form both the major pheromone component, (Z)-9-hexadecenal and the minor one, (Z)-11-hexadecenal. Our data suggest that delta9 desaturase is the major desaturase, and delta11 desaturase is responsible for the minor component in H. assulta, which is consistent with previous work. However, the weak chain shortening acting on (Z)-9 and (Z)-11-octadecenoic acid, which is present in the pheromone glands, does occur in this species to produce (Z)-7 and (Z)-9-hexadecenoic acid. In the hybrid, the major pheromone component, (Z)-11-hexadecenal is produced by delta11 desaturation of palmitic acid, followed by reduction and terminal oxidation. The direct fatty acid precursor of the minor component, (Z)-9-hexadecenoic acid is mainly produced by delta9 desaturation of palmitic acid, but also by delta11 desaturation of stearic acid and one cycle of chain shortening. The greater relative amounts of (Z)-9-hexadecenal in the hybrid are due to the fact that both palmitic and stearic acids are used as substrates, whereas only stearic acid is used as substrate in H. armigera. The evolutionary relationships between the desaturases in several Helicoverpa species are also discussed in this paper.     

Molecular basis of the high-palmitic acid trait in sunflower seed oil

Sunflower (Helianthus annuus L.) seed oil with high palmitic acid content has enhanced thermo-oxidative stability, which makes it well suited to high-temperature uses. CAS-5 is a sunflower mutant line that accumulates over 25 % palmitic acid in its seed oil, compared to 5–8 % in conventional cultivars. The objective of this study was to investigate the molecular basis of the high-palmitic acid trait in CAS-5 through both candidate gene and QTL mapping approaches. An F₂ population derived from the cross between CAS-5 and the conventional line HA-89 was developed. A 3-ketoacyl-ACP synthase II (KASII) locus on a telomeric region of linkage group (LG) 9 of the sunflower genetic map was found to co-segregate with palmitic acid content in this population. The KASII locus explained the vast majority of the phenotypic variation (98 %) of the trait. Two minor QTL affecting palmitic acid content were also found on the lower half of LG 9 and on LG 17. Additionally, QTL associated with other major fatty acids (stearic, oleic, and linoleic acid) were identified on LG 1, 6, and 10. This result may reflect untapped genetic variation that could exist among sunflower cultivars for genes determining fatty acid composition. In addition to demonstrating the major role of a KASII locus in the accumulation of high levels of palmitic acid in CAS-5 seeds, this study stressed the importance of characterizing genes with minor effects on fatty acid profile in order to establish optimal breeding strategies for modifying fatty acid composition in sunflower seed oil.     

Sex pheromone biosynthetic pathway in Spodoptera littoralis and its activation by a neurohormone

Deuterium-labeled fatty acids have been used to elucidate the sex pheromone biosynthetic pathway in Spodoptera littoralis. Label from palmitic acid was incorporated during the scotophase into all the pheromone acetates and their corresponding fatty acyl intermediates. (Z,E)-9,11-tetradecadienyl acetate, the major component of the pheromone blend, is synthesized from palmitic acid via tetradecanoic acid, which, by the action of a specific (E)-11 desaturase and subsequently a (Z)-9 desaturase, is converted into (Z,E)-9,11-tetradecadienoate. By further reduction and acetylation, this compound leads to the dienne acetate. Deuterated precursors applied to the pheromone gland during the photophase were also incorporated into the pheromone. The percentage of labeled (Z,E)-9,11-tetradecadienyl acetate relative to natural compound was significantly higher during the light period. Label incorporation from different intermediates into the pheromone was stimulated by injection of brain-subesophageal ganglion extract during the photophase. The influence of the pheromone biosynthesis-activating neuropeptide on the biosynthetic pathway is discussed.     

Genetic enhancement of palmitic acid accumulation in cotton seed oil through RNAi down‐regulation of ghKAS2 encoding β‐ketoacyl‐ACP synthase II (KASII)

Palmitic acid (C16:0) already makes up approximately 25% of the total fatty acids in the conventional cotton seed oil. However, further enhancements in palmitic acid content at the expense of the predominant unsaturated fatty acids would provide increased oxidative stability of cotton seed oil and also impart the high melting point required for making margarine, shortening and confectionary products free of trans fatty acids. Seed‐specific RNAi‐mediated down‐regulation of β‐ketoacyl‐ACP synthase II (KASII) catalysing the elongation of palmitoyl‐ACP to stearoyl‐ACP has succeeded in dramatically increasing the C16 fatty acid content of cotton seed oil to well beyond its natural limits, reaching up to 65% of total fatty acids. The elevated C16 levels were comprised of predominantly palmitic acid (C16:0, 51%) and to a lesser extent palmitoleic acid (C16:1, 11%) and hexadecadienoic acid (C16:2, 3%), and were stably inherited. Despite of the dramatic alteration of fatty acid composition and a slight yet significant reduction in oil content in these high‐palmitic (HP) lines, seed germination remained unaffected. Regiochemical analysis of triacylglycerols (TAG) showed that the increased levels of palmitic acid mainly occurred at the outer positions, while C16:1 and C16:2 were predominantly found in the sn‐2 position in both TAG and phosphatidylcholine. Crossing the HP line with previously created high‐oleic (HO) and high‐stearic (HS) genotypes demonstrated that HP and HO traits could be achieved simultaneously; however, elevation of stearic acid was hindered in the presence of high level of palmitic acid.     

两种海桐属植物种子油脂肪酸组成的分析评价

采用有机溶剂抽提了海桐属 2种植物 (海桐和皱叶海桐 )的籽油 ,使用气相色谱法 (GC)分析鉴定了其油脂的脂肪酸组分。 2种籽油均含有 6种脂肪酸 ,主要脂肪酸成分均为软脂酸 (C16∶0 )和油酸 (C18∶1)。其含量 ( % )分别为 :软脂酸 (C16∶0 ) 2 9.66,3 4 .72 ;油酸 (C18∶1) 66.4 3 ,62 .54。这两种油脂中 ,单不饱和脂肪酸油酸占优势 ,因而品质优良。提示海桐属植物籽油可作为保健型食用油研究和开发利用     

Control of the biosynthetic pathway of Sesamia nonagrioides sex pheromone by the pheromone biosynthesis activating neuropeptide

(Z)-11-Hexadecenyl acetate, the main pheromone component of Sesamia nonagrioides sex pheromone, is biosynthesized from palmitic acid by Delta(11)-desaturation followed by reduction and acetylation. Production of (Z)-11-hexadecenyl acetate is regulated by the Pheromone Biosynthesis Activating Neuropeptide (PBAN). Transformation of (Z)-11-hexadecen-1-ol into the corresponding acetate is a target step for PBAN in the regulation of this biosynthetic sequence, thus being the first example of a PBAN-activated acetylation. The production of the minor component (Z)-11-hexadecenal is also stimulated by PBAN. The usefulness of pentafluorobenzyloxime-derivatives for the analysis of aldehyde pheromone constituents by gas chromatography coupled to mass spectrometry is also reported.     

金线莲挥发油化学成分的研究

采用水蒸气蒸馏法提取花叶开唇兰挥发油,用GC毛细管柱进行分析,归一化法测定其相对含量,并用GC-MS法鉴定化学成分。检出182个成分,鉴定出73个化合物,占挥发油总量的92.64%,主要成分为:正十六烷酸(25.22%)、(Z,Z)-9,12-十八碳二烯酸甲酯(6.47%)、11,14,17-二十碳三烯酸甲酯(4.42%)、(Z,Z)-9,12-十八碳二烯酸(15.35%)和(Z,Z,Z)-9,12,15-十八碳三烯酸甲酯(13.64%)。