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Elena E. Stashenko William Torres Jairo Ren Martinez Morales 《Journal of separation science》1995,18(2):101-104
Volatile secondary metabolites from Colombian ylang-ylang flowers were obtained by combined steam distillation - solvent extraction. The samples were analyzed by high resolution gas chromatography with flame ionization, nitrogen/phosphorus, or mass spectrometric detection. The chemical composition of the oils extracted from flowers at different stages of development differed both qualitatively and quantitatively. The generation of total volatile metabolites, light oxygenated compounds in particular, increased markedly during flower maturation. In this work the quality of the ylang-ylang essential oils was studied as a function of flower maturity. 相似文献
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A capillary zone electrophoresis (CZE) method for the analyses of kaempferol in Centella asiatica and Rosa hybrids and rutin in Chromolaena odorata was developed. The optimization was performed on analyses of flavonoids (e.g., rutin, kaempferol, quercetin, myricetin, and apigenin) and organic carboxylic acids (e.g., ethacrynic acid and xanthene-9-carboxylic acid) by investigation of the effects of types and amounts of organic modifiers, background electrolyte concentrations, temperature, and voltage. Baseline separation (R(s) = 2.83) of the compounds was achieved within 10 min in 20 mM NaH2PO4 - Na2HPO4 (pH 8.0) containing 10% v/v ACN and 6% v/v MeOH using a voltage of 25 kV, a temperature of 30 degrees C, and a detection wavelength set at 220 nm. The application of the corrected migration time (t(c)), using ethacrynic acid as the single marker, was efficient to improve the precision of flavonoid identification (% relative standard deviation (RSD) = 0.65%). The method linearity was excellent (r2 > 0.999) over 50-150 microg/mL. Precision (%RSD < 1.66%) and recoveries were good (> 96% and %RSDs < 1.70%) with detection and quantitation limits of 2.23 and 7.14 microg/mL, respectively. Kaempferol in C. asiatica and R. hybrids was 0.014 g/100 g (%RSD = 0.59%) and 0.044 g/100 g (%RSD = 1.04%), respectively, and rutin in C. odorata was 0.088 g/100 g (%RSD = 0.06%). 相似文献
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Su-Ching Kuo 《Analytica chimica acta》2009,653(1):91-96
The purpose of this study was to develop and test a diffuse reflectance infrared Fourier transform spectroscopy (DRIFTS) method, a fast and non-destructive method without extraction, and compare it with the standard gas chromatography (GC) method currently used. A micro-orifice uniform deposit impactor (MOUDI) was used to sample all the size distributions of the aerosol particles of essential oils to investigate the relation between size distributions and the indoor concentration distributions of ylang essential oils. Correlation coefficients for DRIFTS and GC were 0.9904, 0.9910, 0.9913, and 0.9983 for eugenol, isoeugenol, methyl ether, and eugenyl acetate, respectively. The results showed that the concentrations of the four eugenol derivatives of smoke were approximately three times higher than those of mist. Additionally, the major size distributions of aerosol were 0.19 μm and 1.8 μm for the smoke and mist methods, respectively. Because these two methods produce similar results, DRIFTS is a practical method for assessing these fragrances in aerosols. 相似文献
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A new aporphine alkaloid was isolated from the stem bark of Cananga odorata Hook. f. et Thomson (Annonaceae). The structure of this alkaloid has been established as ushinsunine N-oxide (6aS, 7R) ( 1 ) on the basis of spectroscopic evidences and by chemical transformation. 相似文献
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SU Ming-lei LIU Cang-wei WANG Yu-rong SUN Hai-yan REN Hai-qing Lü Bin 《光谱学与光谱分析》2018,38(10):3048-3052
实木地板作为一种天然环保的地面铺装材料,得到越来越多消费者的选择,需求量日益剧增,而如何快速了解和检测木材材性一直是地板选材和质量检测急需解决的问题。采用了X射线剖面密度仪和傅里叶红外光谱仪(FTIR)两种快速检测技术,对市场上常用的进口地板材番龙眼和香二翅豆的剖面密度和化学主要组成成分进行了快速测定;同时采用直接测量法测量了木材的基本密度值,并将两种地板材快速测定密度值与实测密度值进行了相关性分析。剖面密度分析结果表明,香二翅豆的平均密度高于番龙眼的平均密度,两种地板材质地均匀性都很好;相关性数据表明番龙眼与香二翅豆两种地板材剖面密度的平均值与其基本密度值都具有很好的相关性,拟合后的相关系数达到了0.983和0.981,所有样品的两种密度的相关系数为0.991;傅里叶红外光谱分析结果表明香二翅豆的抽提物含量要高于番龙眼,香二翅豆木质素的特征峰I1 507/I1 425,I1 507/I1 740的高度比值高于番龙眼的,而纤维素的特征峰I895/I1 425,I895/I1 507高度比值低于番龙眼的,表明香二翅豆的木质素含量高于番龙眼,纤维素含量低于番龙眼。由此可见,X射线剖面密度仪可以快速检测出木材的质地均匀性以及预测木材基本密度值,而FTIR可以快速检测木材化学组分相对含量的高低,两种方法结合可以对实木地板材以及其他木材的物理化学性能进行快速检测。 相似文献
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Bing Liu 《Natural product research》2016,30(4):433-437
Twelve compounds were isolated from the roots of Aglaia odorata. Their structures were established on the basis of NMR and MS data as rocaglaol (1), rocaglamide (2), eichlerialactone (3), sapelins A (4), isofouquierone (5), eichlerianic acid (6), shoreic acid (7), agladupol E (8), 3-epimeliantriol (9), cleomiscosins B (10), 2β,3β-dihydroxy-5α-pregnane-16-one (11) and β-d-glucopyranos-1-yl N-methylpyrrole-2-carboxylate (12). Among them, compounds 1 and 2 showed significant cytotoxicity against human cancer cell (HL-60, SMMC-7721, A-549, MCF-7 and SW480) with IC50 values of 0.007–0.095 μM, while compounds 3–5 and 10 and 11 showed moderate to no cytotoxicity (IC50 0.43 to values >40 μM). Compound 6 showed only weak cytotoxicity (IC50 6.87 to >40 μM) and its epmier 7 was completely inactivite (IC50>40 μM) in the assay. However, potent synergistic effect was observed when the molar ratio of 6 to 7 is between 4:1 and 1:1. 相似文献
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Sixteen compounds, (+)-ushinsunine-β-N-oxide ( 1 ), cleistopholine ( 2 ), liriodenine ( 3 ), (-)-anonaine ( 4 ), (+)-nornuciferine ( 5 ), (+)-N-acetylnornuciferine ( 6 ), (-)-ushinsunine ( 7 ), (-)-norushinsunine ( 8 ), (-)-asimilobine ( 9 ), (+)-reticuline ( 10 ), N-trans-feruloyltyramine ( 11 ), β-sitosterol (12) and stigmasterol ( 13 ), lyscamine ( 14 ), (-)-anaxagoreine ( 15 ) and trans-cinnamic acid ( 16 ) were isolated from the methanolic extract of the Cananga odorata. Among them, 1 is a new stereoisomer of ushinsunine-β-N-oxide. The structures of these compounds were established by means of spectral experiments. 相似文献
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Malai Satiraphan Quoc Dang Thai Uthai Sotanaphun Chavalit Sittisombut Sylvie Michel 《Natural product research》2015,29(19):1820-1827
A new 3,4-seco-cycloartane, identified as (24R,25S)-dihydroxy-26-O-nonadecylcarbonyloxy-3,4-secocycloarta-4(28)-en-3-oic acid (1), has been isolated from the leaves of Hopea odorata Roxb. (Dipterocarpaceae), together with the rare 3,4-seco-cycloart-4(28),24-diene-3,26-dioic acid (2 or abiesatrine J) and six other known compounds (3–8). Their structures were elucidated on the basis of both chemical and spectroscopic methods. 相似文献
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