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1.
A phytochemical investigation of the MeOH extract of Illicium arborescens yielded the two new phytoquinoid epimers, 2,3‐didehydro‐5‐O‐methyl‐11‐epiillifunone E ( 1 ) and 2,3‐didehydro‐5‐O‐methylillifunone E ( 2 ), as well as five new sesquiterpene lactones (8,9‐secoprezizaane‐type sesquiterpenes). Two of them, i.e., 3 and 4 , were minwanensin‐type sesquiterpenes, the other two, i.e., 5 and 6 , had the anisatin‐type (or floridanolide type) skeleton, and the fifth, i.e., 7 , was a dunnianin‐type sesquiterpene. Their structures were established by analyses of 1D‐ and 2D‐NMR, HR‐MS, and chemical evidence. The in vitro cytotoxic activity of compounds 1 – 7 was tested against four human tumor cell lines, including HeLa (cervical epitheloid), WiDr (colon), Daoy (medulloblastoma), and Hep2 (liver carcinoma) human‐tumor cells.  相似文献   
2.
One new sesquiterpene compound, namely, illihenlactone A(1), and one new prenylated C_6–C_3 compound, illihenryione H(2), along with three known sesquiterpenes(3–5) were isolated from the stems of Illicium henryi. The structures of 1 and 2 were elucidated by spectroscopic evidence including NMR, HRESIMS and circular dichroism(CD). Compound 2 exhibited a weak inhibitory ratio for bglucuronidase release induced by platelet-activating factor(PAF) in rat polymorphonuclear leukocytes(PMNs) in vitro.  相似文献   
3.
A new method of extracting essential oils from dried plant materials has been studied. By adding a microwave-absorption medium (MAM) to a reactor, solvent-free microwave extraction (SFME) was improved and can be used to extract essential oils from dried plant material without pretreatment. With a microwave irradiation power of 85 W it took only approximately 30 min to extract the essential oils completely. The whole extraction process is simple, rapid, and economical. Three types of MAM, iron carbonyl powder (ICP), graphite powder (GP), and activated carbon powder (ACP), and two types of dried plant material, Illicium verum Hook. f. and Zingiber officinale Rosc., were studied. The results were compared with those obtained by use of conventional SFME, microwave-assisted hydrodistillation (MAHD), and conventional hydrodistillation (HD), and the conclusion drawn was that improved SFME was a feasible means of extracting essential oils from dried plant materials, because there were few differences between the composition of the essential oils extracted by improved SFME and by the other methods.  相似文献   
4.
八角茴香与其伪品莽草的红外光谱三级鉴定研究   总被引:2,自引:0,他引:2  
采用红外光谱三级鉴定的方法区分和鉴别了八角茴香及其伪品莽草。红外光谱三级鉴定即依次采用一维红外光谱、二阶导数谱和二维相关红外光谱,分辨率逐渐提高,谱图的差别也进一步放大。一维谱图中,两者整体峰形比较相似,但在3 400 cm-1附近八角茴香只出现一个特征峰3 392 cm-1,而莽草则出现3 482和3 387 cm-1两个特征峰。二阶导数谱在850~1 180 cm-1波段八角茴香的几个强峰峰强相对比较接近,其中1 015 cm-1为图中最强峰,而莽草的最强峰在1 070 cm-1附近;在1 180~1 500 cm-1波段八角茴香在1 469,1 454,1 442 cm-1附近的3个特征峰峰强明显强于1 292,1 276,1 266 cm-1附近的特征峰,而莽草则刚好相反。二维相关红外光谱中差异更明显,850~1 165 cm-1波段八角茴香在主对角线上的自动峰较强峰出现在1 153和1 000 cm-1,而莽草峰强较强的自动峰出现在911和878 cm-1;1 165~1 500 cm-1波段八角茴香呈现2个自动峰,而莽草则出现5个自动峰。可见红外三级鉴定方法是一种快速有效的鉴定中药材的方法。  相似文献   
5.
八角的超临界CO2流体萃取产物化学成分的研究   总被引:15,自引:0,他引:15  
采用GC和GC-MS技术对八角的超临界CO2流体萃取物的化学成分进行了研究,共鉴定出34种化合物,它们的含量占出峰物质总量的962%。同时与八角的水蒸汽蒸馏产物的组成进行了比较。  相似文献   
6.
One new sesqui-neolignan compound, namely, sesqui-illisimonan A (1), one new neolignan, illisimonan A (2), and one new phenylpropanoid compound, illisimoid A (3) were isolated from the fruits of Illicium simonsii Maxim. The structures and absolute configurations of these compounds were determined by extensive spectroscopic, including NMR, circular dichroism and calculated electronic circular dichroism methods. The antioxidant activities of compounds 13 were also evaluated. Vitamin E was selected as the positive control (IC50 = 49.73 ± 0.88 μM). Compounds 1 and 2 exhibited in vitro antioxidant activity with an IC50 value of 55.76 ± 1.30 and 59.36 ± 0.50 μM, respectively. However, the compound 3 didn’t show obvious antioxidant activity.  相似文献   
7.
王晓春  王涵文  马继平  徐烨  关亚风 《色谱》2004,22(2):101-105
首次将填充毛细管高效液相色谱-毛细管气相色谱在线联用技术(μ-HPLC-CGC)用于分离分析八角茴香果实的挥发油成分。液相色谱选用氰基分析柱(250 mm×0.32 mm i.d.),正己烷-乙腈-二氯甲烷(体积比为80∶8∶12)为流动相,对挥发油样品做族组分分离,得到的5个族组分被依次存放在多位储存接口内,然后不分流分别转入毛细管气相色谱仪做详细分析。气相色谱柱由10 m×0.53 mm i.d.保留间隔柱和30 m×0.53 mm i.d.×1.0 μm SE-54分析柱组成。采用了不分流柱内进样模  相似文献   
8.
采用顶空固相微萃取与气相色谱-质谱联用技术,对八角茴香中风味物质进行了分析。选用自制聚丙烯酸树脂涂层,对样品量、萃取时间、萃取温度、解吸时间等参数进行了优化,结果表明0.10g样品在60℃水浴中顶空萃取40min,250℃下解吸2min达到最佳条件。比较了顶空固相微萃取与传统水蒸气蒸馏两种前处理方法,分析结果非常相似。该方法可用于快速分析八角茴香中的风味物质。  相似文献   
9.
Previous studies have revealed the numerous biological activities of the fruits of Illicium verum; however, the activities of its leaves and twigs have remained undiscovered. The study aimed to investigate the phytochemical components and antibacterial activity of the various extracts from the leaves and twigs of Illicium verum. The herbal extracts were prepared by supercritical CO2 extraction (SFE) and 95% ethanol extraction, followed by partition extraction based on solvent polarity. Analysis of antimicrobial activity was conducted through the usage of nine clinical antibiotic- resistant isolates, including Staphylococcus aureus, Pseudomonas aeruginosa and Acinetobacter baumannii. Among the tested samples, the SFE extracts exhibited broader and stronger antibacterial activities against the test strains, with a range of MIC between 0.1–4.0 mg/mL and MBC between 0.2–4.5 mg/mL. Observations made through scanning electron microscopy revealed potential mechanism of the antimicrobial activities involved disruption of membrane integrity of the test pathogens. Evaluation of the chemical composition by gas chromatography-mass spectrometry indicated the presence of anethole, anisyl aldehyde, anisyl acetone and anisyl alcohol within the SFE extracts, demonstrating significant correlations with the antibacterial activities observed. Therefore, the leaves and twigs of Illicium verum hold great potential in being developed as new natural antibacterial agents.  相似文献   
10.
Two novel abietane diterpenoids, wardinols A and B ( 1 and 2 , resp.), together with five known diterpenoids, 3 – 7 , were isolated from the fruits of Illicium wardii A.C.Sm . Their structures were elucidated on the basis of intensive spectroscopic analysis, including 1D‐ and 2D‐NMR spectroscopy. Wardinol A ( 1 ) is a rare 9,10‐epoxy‐9,10‐secoabietane diterpenoid. All of the isolated compounds were evaluated for their cytotoxicities against three human tumor cell lines, A549, HCT116, and CCRF‐CEM.  相似文献   
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