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41.
Lonicera maackii (Caprifoliaceae) is a large, upright shrub with fruits that contain many bioactive compounds. Flavonoids are common active substances in L. maackii. However, there is a dearth of information about the accumulation of these flavonoids and their possible medicinal value. We used targeted metabolomics analysis based on ultra-performance liquid chromatography-tandem mass spectrometry (UPLC-MS/MS) to analyze five developmental stages of L. maackii fruit. A total of 438 metabolites were identified in the five developmental stages, including 81 flavonoids and derivatives. The 81 flavonoids included 25 flavones and derivatives, 35 flavonols and derivatives, two isoflavones, three cyanidins and derivatives, eight procyanidins, and eight flavanones. In addition, we outlined the putative flavonoid biosynthesis pathway and screened their upstream metabolites. More importantly, we analyzed the accumulation patterns of several typical flavones and flavonols. The results reported here improved our understanding of the dynamic changes in flavonoids during fruit development and contributed to making full use of the medicinal value of L. maackii fruit.  相似文献   
42.
Luteoloside is a potential anticarcinogenic component isolated from Lonicera japonica, a traditional Chinese medicine (TCM). This study details the development and validation of a sensitive and accurate HPLC‐ESI‐MS/MS method for the quantification of luteoloside in dog plasma. Sample pretreatment includes simple protein precipitation using methanol–acetonitrile (1:1, v/v). A Phenomenex Gemini C18 column (2.0 × 50 mm, i.d., 3.5 µm) was used to separate luteoloside and internal standard by gradient mode with mobile phase consisting of water containing 0.1% formic acid and methanol containing 0.1% formic acid at a flow rate of 0.40 mL/min with a column temperature of 25°C. The detection was performed by positive ion electrospray ionization (ESI) in multiple reaction monitoring mode. The calibration curves were linear (R > 0.995) over the concentration range 1.0–2000 ng/mL and the lower limit of quantification was 1.0 ng/mL. The intra‐day and inter‐day precisions (RSD) were all <15%, accuracies (RE) were within the range of ±15%, and recoveries were between 85.0 and 115%. The validated HPLC‐ESI‐MS/MS method was successfully applied to determine plasma concentrations of luteoloside after intravenous administration of luteoloside at a dose level of 20 mg/kg. Copyright © 2012 John Wiley & Sons, Ltd.  相似文献   
43.
绿原酸乙酯的NMR研究   总被引:2,自引:0,他引:2  
相婷  侯捷 《波谱学杂志》1997,14(5):387-391
从西南忍冬中分离得到了绿原酸乙酯,该化合物系首次从该属植物中获得。我们应用^1H NMR、^13C-NMR、HSQC、HMBC等核磁共振技术明确归属了其碳信号及氢信号,并订正了文献中对部分信号的错误归属。  相似文献   
44.
Two Triterpenoid Saponins from Lonicera Japonica   总被引:1,自引:1,他引:0  
The flowers of Lonicera japonica Thunb are a Chinese traditional medicine and have thefunctions such as anti-bacteria, anti-virus and hepato-protective. A new triterpenoidsaponin 2, together with a known saponin l, was obtained ftom its flowers. This papermainly discussed the structure elucidation of these two saponins.Acid hydrolysis ofsaponin 1 and 2 yielded the same aglycon. By comparing 1 H and13C NMR data, the aglycon was determined to be hederageninl. This result was alsoconfirmed by…  相似文献   
45.
忍冬的花内蜜腺分布在花冠简内侧的基部。蜜腺由分泌表皮和产蜜组织组成,属于花被蜜腺。分泌表皮的大部分细胞特化为单细胞的蜜腺毛,其顶端的角质层厚薄不均匀,在蜜腺组织的发育过程中,蜜腺毛中的液泡变化较为明显,产蜜组织细胞中的淀粉粒也呈现出一定的消长规律。泌蜜期间,密腺毛的角质层与细胞壁分离,其间充满蜜汁,蜜汁通过薄的角质层处泌出。  相似文献   
46.
A new iridoid glycoside, methyl (3R,4R,4aS,7S,7aR)‐3‐hydroxy‐7‐methyl‐5‐oxooctahydrocyclopenta[c]pyran‐4‐carboxylate‐3‐O‐β‐d ‐(1′S,2′R,3′S,4′S,5′R)‐glucopyranoside, named loniceroside A, C17H26O10, ( 1 ), was obtained from the aerial parts of Lonicera saccata. Its structure was established based on an analysis of spectroscopic data, including 1D NMR, 2D NMR and HRESIMS, and the configurations of the chiral C atoms were determined by X‐ray crystallographic analysis. The single‐crystal structure reveals that the cyclopenta[c]pyran scaffold is formed from a five‐membered ring and a chair‐like six‐membered ring connected through two bridgehead chiral C atoms. In the solid state, the glucose group of ( 1 ) plays an important role in constructing an unusual supramolecular motif. The structure analysis revealed adjacent molecules linked together through intermolecular O—H…O hydrogen bonds to generate a banded structure. Furthermore, the banded structures are linked into a three‐dimensional network by interesting hydrogen bonds. Biogenetically, compound ( 1 ) carries a glucopyranosyloxy moiety at the C‐3 position, representing a rare structural feature for naturally occurring iridoid glycosides. The growth inhibitory effects against human cervical carcinoma cells (Hela), human lung adenocarcinoma cells (A549), human acute mononuclear granulocyte leukaemia (THP‐1) and the human liver hepatocellular carcinoma cell line (HepG2) were evaluated by the MTT method.  相似文献   
47.
This study presents a new HPLC method for the simultaneous determination of seven major components, namely chlorogenic acid, caffeic acid, loganin, sweroside, secoxyloganin, rutin and luteolin 7-O-glucoside in Caulis Lonicerae Japonicae, a commonly used traditional Chinese medicinal herb derived from the caulis of Lonicera japonica Thunb. These seven compounds, belonging to the chemical types of phenolic acids, iridoids and flavonoids, were separated on a C18 column (250 x 4.6 mm, 5.0 microm) with the column temperature at 30 degrees C. The mobile phase was composed of (A) aqueous acetic acid (0.4%, v/v) and (B) acetonitrile using a gradient elution of 10% B at 0-12 min, 10-17% B at 12-25 min and 17% B at 25-35 min. The flow rate was 1.0 mL/min and detection wavelength was set at 245 nm. The limit of detection (S/N = 3) ranged from 0.10 to 0.23 microg/mL and the limit of quantification (S/N = 10) ranged from 0.69 to 3.56 microg/mL. All calibration curves showed good linear regression (r2 > 0.9990) within the test ranges. The intra- and inter-day precisions as determined from sample solutions were below 1.24 and 2.28%, respectively. The recoveries for seven compounds were found to range from 94.2 to 103.6%. This verified method has been successfully applied to evaluation of commercial samples of Caulis Lonicerae Japonicae from different markets in China.  相似文献   
48.
An ultrahigh pressure extraction (UPE)-high performance liquid chromatography (HPLC)/diode array detector (DAD) method was established to evaluate the quality of Lonicera japonica Thunb. Ten active components, including neochlorogenic acid, chlorogenic acid, 4-dicaffeoylquinic acid, caffeic acid, rutin, luteoloside, isochlorogenic acid B, isochlorogenic acid A, isochlorogenic acid C, and quercetin, were qualitatively evaluated and quantitatively determined. Scanning electron microscope images elucidated the bud surface microstructure and extraction mechanism. The optimal extraction conditions of the UPE were 60% methanol solution, 400?MPa of extraction pressure, 3?min of extraction time, and 1:30 (g/mL) solid:liquid ratio. Under the optimized conditions, the total extraction yield of 10 active components was 57.62?mg/g. All the components showed good linearity (r2 ≥ 0.9994) and recoveries. This method was successfully applied to quantify 10 components in 22 batches of L. japonica samples from different areas. Compared with heat reflux extraction and ultrasonic-assisted extraction, UPE can be considered as an alternative extraction technique for fast extraction of active ingredient from L. japonica.  相似文献   
49.
金银花中总黄酮的光谱分析及抗氧化性能测定   总被引:13,自引:0,他引:13  
采用超声波法从金银花中提取黄酮类化合物,并建立了金银花中总黄酮的光谱分析方法。本法的回收率为98.0%~103.0%,RSD<0.62%。并用流动注射化学发光法研究了金银花的抗氧化性能,实验结果表明:金银花具有较强的抗氧化性能。  相似文献   
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