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1.
It is thought that the therapeutic efficacy of Morus alba L. is determined by its biological compounds. We investigated the chemical differences in the medicinal parts of M. alba by analyzing a total of 57 samples (15 root barks, 11 twigs, 12 fruits, and 19 leaves). Twelve marker compounds, including seven flavonoids, two stilbenoids, two phenolic acids, and a coumarin, were quantitatively analyzed using a high-performance liquid chromatography-diode array detector and chemometric analyses (principal component and heatmap analysis). The results demonstrated that the levels and compositions of the marker compounds varied in each medicinal part. The leaves contained higher levels of six compounds, the root barks contained higher levels of four compounds, and the twigs contained higher levels of two compounds. The results of chemometric analysis showed clustering of the samples according to the medicinal part, with the marker compounds strongly associated with each part: mulberroside A, taxifolin, kuwanon G, and morusin for the root barks; 4-hydroxycinnamic acid and oxyresveratrol for the twigs and skimmin; chlorogenic acid, rutin, isoquercitrin, astragalin, and quercitrin for the leaves. Our approach plays a fundamental role in the quality evaluation and further understanding of biological actions of herbal medicines derived from various medicinal plant parts.  相似文献   
2.
欧阳臻  陈钧  李永辉 《分析化学》2005,33(6):817-820
建立了芴甲氧酰氯(FMOC—Cl)柱前荧光衍生一高效液相色谱法测定桑叶中1-脱氧野尻霉素(DNJ)的方法。桑叶经0.05mol/L,盐酸提取,在pH8.5的硼酸盐缓冲溶液条件下,DNJ反应生成荧光产物,然后用高效液相色谱-荧光检测器测定。流动相为乙腈-0.1%醋酸(55:45,V/V)。线性范围为0.567~34mg/L(相关系数r=0.9999);检出限为0.03mg/L。实验测得桑叶中DNJ含量为0.24%;平均回收率为97.1%,RSD为1.35%(n=6)。  相似文献   
3.
Methyl ester derivatives of fatty acids were analyzed for the determination of the constituents of Datura alba seed oil. Gas chromatography coupled to mass spectrometer was used for these analyses. Results delivered that there were saturated as well as unsaturated fatty acids in Datura alba seed oil. Total of 15 different fatty acid components were identified and quantified. Methyl linoleate was found in highest concentration (16.22%) among the identified analytes of interest. In addition methyl esters of Palmitic acid (6.59%), Oleic acid (5.41%) and Stearic acid (1.35%) were found. Concentrations of rest of the detected fatty acids were less than 1%. From the literature it appears that no such work has been performed for the determination of fatty acids in Datura alba seed oil.  相似文献   
4.
Ethanol extract and fractions obtained from fresh and dry aerial parts of Lippia alba were examined in order to determine their phytochemical composition, antioxidant capacity and antibacterial activities. The ethanol extracts and fractions exhibited an antioxidant effect by the DPPH assay, especially samples of fresh plant. HPLC analysis of the ethyl acetate fractions identified the presence of phenolic acids and flavonoids. The ethanol extract and fractions showed activity against reference and multidrug-resistant strains of Staphylococcus aureus and Enterococcus faecalis (MIC range 2000–250 μg/mL). The hexane and dichloromethane fractions of fresh plant showed better activity against reference strains of Escherichia coli (MIC of 250 and 125 μg/mL, respectively), but all extracts and fractions were less active against multidrug-resistant strains of all the Gram-negative species evaluated. The results showed that the extract and fractions of L alba aerial parts showed antibacterial activity, even against multidrug-resistant Gram-positive bacteria, and antioxidant effect (DPPH assay).  相似文献   
5.
Chemical investigation of the root bark of Morus alba led to the isolation of a new flavone, dioxycudraflavone A (1) and a new 2-arylbenzofuran, 5-hydroxyethyl moracin M (2), together with seven known compounds namely sanggenon V (3), morusin (4), morusignin L (5), licoflavone C (6), moracin C (7), alfafuran (8) and mulberrofuran G (9). The structure elucidation of these compounds was based on analyses of spectroscopic data including 1D, 2D NMR and HR-ESI-MS. All compounds were evaluated for the α-glucosidase inhibitory and cytotoxic activities. Compounds 24, 8 and 9 exhibited strong α-glucosidase inhibitory activities with IC50 less than 10 μM, while only 4 and 9 showed moderate cytotoxic effects against lung cancer cells.  相似文献   
6.
Cultivation location, maturity levels, and extraction solvents could affect the bioactive compounds and biological activities of mulberry (Morus alba Linnaeus). The lack of study on Malaysia-grown mulberry causes its underutilization. This study investigated the bioactive compound content and the antioxidant activity of Sabah-grown mulberry at two different maturity stages (fruits: red mature and black fully ripe; leaves: young and mature) extracted using 70% (v/v) methanol, 60% (v/v) ethanol, and 65% (v/v) acetone. Analyses showed that mulberry fruits demonstrated maturity-dependent increment (except UHPLC-DAD quantification), while the leaves revealed maturity-dependent reduction. Principal component analysis (PCA) displayed 65% (v/v) acetone black fully ripe fruits as the best phenolics and antioxidant sources. However, the 60% (v/v) ethanol black fully ripe fruits contained 20.08–68.43% higher total anthocyanins. Meanwhile, the 65% (v/v) acetone and 70% (v/v) methanol red mature fruits were higher in chlorogenic acid (27.53–47.12%) and rutin (31.42–35.92%) than other fruit extracts, respectively. For leaves, 65% (v/v) acetone young leaves were the best phenolics and antioxidant sources. However, the 60% (v/v) ethanol young leaves possessed greater chlorogenic acid (19.56–74.11%) than other leaf extracts. Overall, Malaysia-grown mulberry is rich in phenolics and antioxidants, suggesting its potential application in food and pharmaceutical products.  相似文献   
7.
采用微波消解技术-电感耦合等离子-原子发射光谱法(ICP-AES)对不同产地、不同生长年限的芍药及其炮制前后含有的几种具有重要生理功能的无机微量元素——K,Ca,Na,Mg,Za,Fe和Cu等的含量进行了依次测定。结果显示样品中含有丰富的微量元素,该方法的RSD均在4%以下,加标回收率在99%~113%,具有较好的准确度和精密度。进而采用主成分分析法(PCA)对所测得的白芍样品微量元素作为变量进行分类研究。结果表明微波消解-电感耦合等离子-原子发射光谱法可同时测定多种微量元素,主成分分析法是不同白芍的分析分类的有效方法,实验结果可为白芍中微量元素与其药效的相关性提供科学依据。  相似文献   
8.
From the whole plant of Morina nepalensis var. alba Hand.‐Mazz., two new acylated flavonoid glycosides ( 1 and 2 ), together with four known flavonoid glycosides ( 3–6 ), were isolated. Their structures were determined to be quercetin 3‐O‐[2″′‐O‐(E)‐caffeoyl]‐α‐L ‐arabinopyranosyl‐(1→6)‐β‐D ‐galactopyranoside (monepalin A, 1 ), quercetin 3‐O‐[2″′‐O‐(E)‐caffeoyl]‐α‐L ‐arabinopyranosyl‐(1→6)‐β‐D ‐glucopyranoside (monepalin B, 2 ), quercetin 3‐O‐α‐L ‐arabinopyranosyl‐(1→6)‐β‐D ‐galactopyranoside (rumarin, 3 ), quercetin 3‐O‐β‐D ‐galactopyranoside ( 4 ), quercetin 3‐O‐β‐D ‐glucopyranoside ( 5 ) and apigenin 4O‐β‐D ‐glucopyranoside ( 6 ). Their structures were determined on the basis of chemical and spectroscopic evidence. Complete assignments of the 1H and 13C NMR spectra of all compounds were achieved from the 2D NMR spectra, including H–H COSY, HMQC, HMBC and 2D HMQC‐TOCSY spectra. Copyright © 2002 John Wiley & Sons, Ltd.  相似文献   
9.
The lawsone content has been evaluated quantitatively in eight commercial henna powders and two collected henna leaves. The phenolic, chloroform-soluble fraction of the majority of the examined samples showed the presence of lawsone and two other pigments. Here we aimed to optimize high performance thin layer chromatography for the determination of lawsone. Upon using the optimized method the examined samples showed considerable variation in lawsone concentration ranging from 0.004 up to 0.608 wt%, indicating that some samples were almost devoid of lawsone. Some of these products were subjected to preliminary in vivo toxicity studies.  相似文献   
10.
Salvia miltiorrhiza Bge. var. alba C.Y. Wu and H.W. Li has wide prospects in clinical practice. A useful comprehensive method was developed for the quality evaluation of S. miltiorrhiza var. alba by three quantitative parameters: high‐performance liquid chromatography fingerprint, ten‐component contents, and antioxidant activity. The established method was validated for linearity, precision, repeatability, stability, and recovery. Principal components analysis and hierarchical clustering analysis were both used to evaluate the quality of the samples from different origins. The results showed that there were category discrepancies in quality of S. miltiorrhiza var. alba samples according to the three quantitative parameters. Multivariate linear regression was adopted to explore the relationship between components and antioxidant activity. Three constituents, namely, danshensu, rosmarinic acid, and salvianolic acid B, significantly correlated with antioxidant activity, and were successfully elucidated by the optimized multivariate linear regression model. The combined use of high‐performance liquid chromatography fingerprint analysis, simultaneous multicomponent quantitative analysis, and antioxidant activity for the quality evaluation of S. miltiorrhiza var. alba is a reliable, comprehensive, and promising approach, which might provide a valuable reference for other herbal products in general to improve their quality control.  相似文献   
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