珙桐叶总黄酮提取工艺及体外抗氧化性

运用正交试验设计探讨了绵竹白云山珙桐叶黄酮的微波辅助提取工艺条件,并对提取液的抗氧化性能进行了研究。结果表明,珙桐叶总黄酮提取的最佳工艺参数：微波功率700W,料液比（g/mL）1∶40,乙醇质量分数浓度为70%,提取时间为2min,测得每克干叶中总黄酮含量为71.03mg。对提取液的抗氧化性研究表明,珙桐叶总黄酮对超氧阴离子自由基、羟基自由基的清除率较好,在实验所选浓度范围内,总还原能力随浓度增加而增强。     

Chemical constituents isolated from stems of Schisandra chinensis and their antifeedant activity against Tribolium castaneum

Abstract

One new sesquiterpene (α-iso-cubebenol acetate, 8), together with 9 known compounds (1-7, 9, 10) were isolated from the stems of Schisandra chinensis (Turcz.) Baill. by repeated silica gel column chromatography. Based on the results of MS, NMR spectra and comparing with literature data, the six dibenzocyclooctadiene lignans were identified as schizandrin A to C (1-3), schizandrin (4), schisantherin A (5) and gomisin J (6), the two sesquiterpenes were identified as α-iso-cubebenol (7) and α-iso-cubebenol acetate (8), while the two triterpenic acids were identified as ganwuweizic acid (9) and kadsuric acid (10). The antifeedant activity of the 10 compounds against Tribolium castaneum adults was tested. Gomisin J (6) exhibited activity at 1500?ppm concentration with 40.3% antifeeding index percentages. As for the dibenzocyclooctene lignans (compounds 1–3, 6), the number of methylenedioxies and the position of hydroxyl groups were the main factors to affect their antifeedant activities.     

UFLC–MS/MS method for simultaneous determination of six lignans of Schisandra chinensis (Turcz.) Baill. in normal and insomniac rats brain microdialysates and homogenate samples: towards an in‐depth study for its sedative‐hypnotic activity

Schisandra chinensis (Turcz.) Baill., a traditional Chinese medicine, has been clinically used for the treatment of insomnia for centuries. The insomnia mechanism and the possible active ingredients of S. chinensis remain largely unknown. The objective of this study was to develop a method to detect its components which could pass through the blood brain barrier (BBB) by determining the brain microdialysate and brain tissue homogenate samples and then obtain the pharmacokinetic profile in brain for comprehensive understanding of its hypnotic clinical efficacy. Therefore, an efficient, sensitive and selective ultra fast liquid chromatography/tandem mass spectrometry method for the simultaneous determination of six sedative and hypnotic lignans (schisandrin, schisandrol B, schisantherin A, deoxyshisandrin, γ‐schisandrin and gomisin N) of Schisandra chinensis (Turcz.) Baill. in rat brain tissue homogenate and brain microdialysates has been developed and validated. The analysis was performed on a Shim‐pack XR‐ODS column (75 mm × 3.0 mm, 2.2 µm) using gradient elution with the mobile phase consisting of acetonitrile and 0.1% formic acid water. The method was validated in brain homogenate and microdialysate samples, which all showed good linearity over a wide concentration range (r² > 0.99), and the obtained lower limit of quantification was 0.1 ng · ml^?1 for the analytes in brain microdialysate samples. The intra‐ and inter‐day assay variability was less than 15% for all analytes. The study proved the six lignans, as sedative and hypnotic ingredients, could pass through the BBB with brain targeting, distributed mainly in the hypothalamus and possessed complete pharmacokinetics process in brain. The results also indicated that significant difference in pharmacokinetic parameters of the analytes was observed between two groups, while absorptions of these analytes in insomniac group were significantly better than those in normal group. Copyright © 2013 John Wiley & Sons, Ltd.     

Development of a quality evaluation method for Fructus schisandrae by pressurized capillary electrochromatography

A pressurized CEC (pCEC) method with postcolumn detection cell had been developed for quantifying the lignans from Fructus schisandrae extracts. The effects of different experimental conditions, such as the ACN content of the mobile phase, the concentration and pH of the buffer, the applied voltage, and the supplementary pressure were studied. Five lignans (schisandrin, gomisin A, schisantherin C, deoxyschizandrin, schisandrin B) were baseline separated using a mobile phase of ACN-phosphate buffer (pH 5.4; 5 mM) (40:60 v/v) under -4 kV applied voltage. The method showed the satisfactory retention time and peak area repeatability. The calibration curves were linear in the range 50.0-1000.0 microg/mL for schisandrin, 20.0-500.0 microg/mL for gomisin A, 10.0-200.0 microg/mL for schisantherin C, 20.0-500.0 microg/mL for deoxyschizandrin, and 20.0-500.0 microg/mL for schisandrin B. The correlation coefficients were between 0.9978 and 0.9989. With this pCEC system, fingerprints of F. schisandrae were preliminarily established to distinguish two members S. chinensis (Turcz.) Baill. and S. sphenanthera Rehd. Et Wils. of F. schisandrae by characteristic peaks, and evaluate the quality of various sources of raw materials by determining the contents of the five lignans.     

Ionic liquid-based microwave-assisted extraction of essential oil and biphenyl cyclooctene lignans from Schisandra chinensis Baill fruits

Ionic liquid-based microwave-assisted extraction (ILMAE) has been successfully applied in extracting essential oil and four kinds of biphenyl cyclooctene lignans from Schisandra chinensis Baill. 0.25 M 1-lauryl-3-methylimidazolium bromide ionic liquid is selected as solvent. The optimum parameters of dealing with 25.0 g sample are 385 W irradiation power, 40 min microwave extraction time and 1:12 solid-liquid ratio. The yields of essential oil and lignans are 12.12±0.37 ml/kg and 250.2±38.2 mg/kg under the optimum conditions. The composition of the essential oil extracted by hydro-distillation, steam-distillation and ILMAE is analyzed by GC-MS. With ILMAE method, the energy consumption time has not only been shortened to 40 min (hydro-distillation 3.0 h for extracting essential oil and reflux extraction 4.0 h for extracting lignans, respectively), but also the extraction efficiency has been improved (extraction of lignans and distillation of essential oil at the same time) and reduces the environmental pollution. S. chinensis materials treated by different methods are observed by scanning electronic microscopy. Micrographs provide more evidence to prove that ILMAE is a better and faster method. The experimental results also indicate that ILMAE is a simple and efficient technique for sample preparation.     

Microwave-assisted extraction and fingerprint studies of Schisandra chinensis (Turcz.) by high performance liquid chromatography and gas chromatography

In order to choose an appropriate extraction method, samples of Schisandra chinensis (Turcz.) Baill were extracted by different methods and it was found that microwave-assisted extraction gave the best results. The contents of schisandrin, schisantherin, deoxyschizandrin, and r-schizandrin of 10 samples collected from different regions in China were determined by HPLC. The chromatograms of ten samples were used to establish the fingerprints of Schisandra chinensis (Turcz.) Baill and two methods based on HPLC and GC were applied to them simultaneously. The fingerprints consisted of 18 common peaks obtained by HPLC and 17 common peaks obtained by GC, which showed good stability and repeatability with RSD less than 3% for retention time. The fingerprints are suitable for identifying and differentiating samples by geographical origin and can be used for quality control.     

传统藏药材波棱瓜的微量元素分析

对传统藏药材波棱瓜中12种微量元素进行了分析。结果显示，在波棱瓜中人体必需微量元素Cu、Fe、Zn、Mn、Co、Ni、Cr、Se等含量较高；对西藏地区不同产地的波棱瓜中的微量元素含量作比较，有极显著差异。提示在选用药材时，应重视其产地。     

Anti-diabetic Effects of Polysaccharides from Ethanol-insoluble Residue of Schisandra chinensis(Turcz.) Baill on Alloxan-induced Diabetic Mice

The ethanol-insoluble residue of Schisandra generated during lignans industrial production is usually treated as solid waste. However, there is active polysaccharide which could be used in it. In this work, the water-soluble polysaccharides from the ethanol-insoluble residue of Schisandra(ESCP) were obtained and their anti-diabetic effect was evaluated. The results indicate that ESCP could significantly reduce the blood glucose level in alloxan-induced diabetic mice. Moreover, the ESCP could significantly improve the lipid metabolism and increase the content of liver glycogen in alloxan-induced diabetic mice. The results indicate that ESCP could be developed into a potential natural hypoglycemic agent.     

北五味子中一种新的莽草酸衍生物的分离纯化及其含量测定

从北五味子中提取分离得到一种新的莽草酸衍生物, 经一维、二维核磁共振波谱(1D NMR, HMQC, HMBC)等数据解析, 鉴定为莽草酸正丁酯. 并采用ZORBAX Extend C18柱, 以乙腈-0.05%磷酸为流动相进行梯度洗脱, 检测波长为215 nm, 流速1.0 mL/min, 建立了北五味子中莽草酸正丁酯含量的高效液相色谱分析方法. 结果表明, 莽草酸正丁酯在2~65 μg/mL浓度范围内线性关系良好, 相关系数r=0.9999, 平均回收率为98.25%, 相对标准偏差(RSD)为1.55%, 表明本法简单准确, 重复性好.     

珙桐热休克蛋白序列分析及功能预测

从本实验室已构建好的珙桐种子cDNA文库中获得热休克蛋白18(HSP18)核苷酸序列,该序列编码蛋白属小热休克蛋白(sHSP).用生物信息学的方法对HSP18从同源性、氨基酸组成、理化性质、疏水性/亲水性、信号肽、跨膜结构域、卷曲螺旋、蛋白质二级及三级结构进行预测和分析.结果表明,珙桐HSP18是不具有信号肽、没有跨膜...