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51.
采用微波消化法和马弗炉干灰法处理天然和栽培缬草根样品,火焰原子吸收光谱法连续测定样品中金属元素,分别检出12种和11种元素,其中Zn、Cu、Fe、Co、Mn、Ni、Cr为生命必需微量元素;两种样品各用两种消化法处理,测得金属元素及含量有差异,干灰法操作简单,但消化温度高、时间长、易挥发、元素容易损失,使检测值偏低;而微波消化法简便、省时、损失减少;两种消化法的加标回收率分别为95%-100%和96%-105%。  相似文献   
52.
Xanthine oxidase (XOD) inhibition has long been considered an effective anti-hyperuricemia strategy. To identify effective natural XOD inhibitors with little side effects, we performed a XOD inhibitory assay-coupled isolation of compounds from Smilacis Glabrae Rhizoma (SGR), a traditional Chinese medicine frequently prescribed as anti-hyperuricemia agent for centuries. Through the in vitro XOD inhibitory assay, we obtained a novel XOD inhibitor, 5-O-caffeoylshikimic acid (#1, 5OCSA) with IC50 of 13.96 μM, as well as two known XOD inhibitors, quercetin (#3) and astilbin (#6). Meanwhile, we performed in silico molecular docking and found 5OCSA could interact with the active sites of XOD (PDB ID: 3NVY) with a binding energy of −8.6 kcal/mol, suggesting 5OCSA inhibits XOD by binding with its active site. To evaluate the in vivo effects on XOD, we generated a hyperuricemia mice model by intraperitoneal injection of potassium oxonate (300 mg/kg) and oral gavage of hypoxanthine (500 mg/kg) for 7 days. 5OCSA could inhibit both hepatic and serum XOD in vivo, together with an improvement of histological and multiple serological parameters in kidney injury and HUA. Collectively, our results suggested that 5OCSA may be developed into a safe and effective XOD inhibitor based on in vitro, in silico and in vivo evidence.  相似文献   
53.
川芎浓缩颗粒挥发性成分分析   总被引:5,自引:0,他引:5  
采用气相色谱-质谱法对川芎浓缩颗粒挥发性成分进行分离鉴定。从水蒸气蒸馏法工艺制备的浓缩颗粒(样品I)中分离鉴定了12个成分,主要为亚油酸、棕榈酸;从超临界CO2流体萃取工艺制备的浓缩颗粒(样品Ⅱ)中分离鉴定了32个成分,主要为藁本内酯、亚油酸。用面积归一化测定了样品Ⅰ、Ⅱ中成分的相对百分含量。  相似文献   
54.
源于中药选择性效应的新型免疫抑制疗法   总被引:3,自引:0,他引:3  
近年来免疫学的发展日新月异,但与其他系统药物相比,免疫系统药物的发展十分落后。低选择性是现有免疫抑制剂的重要缺陷,这使得需要长期用药的自身免疫性疾病常因药物的严重副作用而使治疗无法持续。因此,免疫系统药物的研制必须另辟蹊径。本文在阐述免疫抑制剂发展现状的基础上,通过本课题组关于中药及其成分的研究结果,提出了选择性抑制活化T细胞的免疫抑制新模式,从作用特点、作用机理、代谢产物以及与现有免疫抑制剂的比较等角度论证了选择性免疫抑制的可行性,从而为免疫性疾病的治疗以及新型免疫抑制剂的研制提供新的思路。  相似文献   
55.
白术挥发性成分的超临界流体萃取及其分析   总被引:5,自引:0,他引:5  
采用超临界流体萃取白术挥发油成分,对萃取条件进行优化,并用气相色谱、气相色谱-质谱分析鉴定出超临界流体萃了的挥发油中22个化合物。最佳的超临界流体萃取条件为压力22.0MPa,温度60℃,0.5mL乙醇作改性,先静态萃取10min(CO2用量2.0mL),再动态萃取40min(CO2流速为0.3mL/min)。将超临界流体萃取与水蒸气蒸馏进行对比,水蒸气蒸馏5h的油收率仅为超临界流体萃取1h油收率的10.32%,证明超临界流体萃取替代传统萃取的必要性。  相似文献   
56.
Cao J  Chen J  Yi L  Li P  Qi LW 《Electrophoresis》2008,29(11):2310-2320
Oil-in-water (O/W) and water-in-oil (W/O) MEEKC were compared for their abilities to separate and detect eight phenolic acids and five diterpenoids in Radix et Rhizoma Salviae Miltiorrhizae (RRSM). The effects of oil type and concentration, organic modifier, SDS, and buffer concentration on separation were examined in order to optimize the two methods. Oil contents and organic modifier were found to markedly influence the separation selectivity for both O/W and W/O systems. SDS concentration rarely affected separation resolution for O/W MEEKC, and separation of eight phenolic acids and five diterpenoids could be improved by changing the buffer concentration for W/O MEEKC. A highly efficient O/W MEEKC separation method, where the 13 compounds were separated with baseline resolution, was achieved by using a microemulsion solution of pH 8.0 containing 0.6% cyclohexane, 3.0% SDS, 6.0% 1-butanol, and 3.0% ACN. The W/O MEEKC was unable to resolve all the components. In addition, the analytic time in O/W MEEKC was shorter than that in W/O MEEKC. Finally, the developed O/W MEEKC method was successfully applied to determine analytic compounds in RRSM samples.  相似文献   
57.
为了建立黄连色度测量方法并分析其与有效成分含量之间的相关性,应用灰色关联分析(GRA)与主成分分析(PCA)对不同产地黄连药材进行质量评价。收集了来自15个不同产区黄连药材,依据国际照明委员会CIE L*a*b*数字化系统,采用分光测色计测定15批黄连药材色度值,采用高效液相色谱(HPLC)测定表小檗碱、黄连碱、巴马汀和盐酸小檗碱4种生物碱含量,并运用SPSS 23.0软件对色度与生物碱含量进行相关性分析。将黄连药材中生物碱类成分含量、药材水分、灰分、浸出物含量及色度值作为考察指标,采用GRA法构建黄连质量评价模型并采用SIMCA-P 14.1软件进行PCA及正交偏最小二乘法分析;结果表明,色度测量方法准确可靠;相关性分析结果显示,黄连色度L*a*b*Eab* (总色度值)值与表小檗碱、黄连碱、巴马汀和盐酸小檗碱的含量均有显著相关性。GRA分析结果显示,产地为重庆市的黄连与最优参考序列的相对关联度最高、质量最优;PCA分析结果显示产地为陕西省铜川市的黄连对主成分贡献率较高。GRA与色度测定所建立的黄连质量评价模型可作为黄连药材质量评价的参考依据。  相似文献   
58.
中药药对的化学成分研究川芎-赤芍挥发油的GC/MS分析   总被引:9,自引:0,他引:9  
中药药对是复方的最小组成单位,具有中药配伍的基本特点. 药对化学是复方化学的核心内容. 联用色谱和化学计量学方法为中药复杂体系的分离与分辨提供了强有力的工具. 采用GC-MS法分离测定中药药对川芎-赤芍、 单味药川芎和赤芍的挥发油成分,并对其中的重叠色谱峰采用化学计量学解析方法(CRM)进行分辨,得到药对和各单味药的纯色谱曲线和质谱图,药对川芎-赤芍、 单味药川芎和赤芍分别分辨出82,78和57个色谱峰,通过质谱库对分辨的纯组分进行定性,分别得到61,52和33个定性结果,占总含量的90.18%,95.14%和95.82%.  相似文献   
59.
In this work, the antitumor constituent β‐elemene was selectively separated from the volatile oil of the Curcumae Rhizoma by countercurrent chromatography with silver nitrate as selective reagent based on the formation of coordination complexes. A biphasic solvent system composed of n‐hexane/methanol/water (2:1.5:0.5, v/v/v) was selected, in which 0.15 mol/L of silver nitrate was added to the aqueous phase. The aqueous phase was used as the stationary phase for separation of β‐elemene by countercurrent chromatography after it was partially purified from the volatile oil by silica gel column chromatography. An enriched β‐elemene fraction was obtained by silica gel column chromatography to improve the percentage of β‐elemene from 16.5 to 46.1%. Subsequently, β‐elemene was further purified from 445 mg of the partially purified sample of volatile oil by countercurrent chromatography with silver nitrate as a selective reagent, yielding 145 mg of β‐elemene with greater than 99% purity, as determined by gas chromatography mass spectrometry. The recovery of β‐elemene from the crude volatile oil through two steps was around 63.6%.  相似文献   
60.
In this study,the protective effects of Cimicifugae Rhizoma(CR) was demonstrated in Pseudomonas aeruginosa-induced pneumonia mouse model.To identify the anti-inflammatory ingredients,an ultraperformance liquid chromatography quadrupole time-of-flight mass spectrometry(UPLC/Q-TOF-MS)integrated nuclear factor κB(NF-κB) luciferase reporter assay screening system was carried out.As a result,some caffeic acid derivatives,including caffeic acid,ferulic acid/isoferulic acid,fukinolic acid,and cimicifugic acid ingredients were identified as the potential effective compounds from CR.For testing the anti-inflammatory capacity,caffeic acid was demonstrated to inhibit NF-kB and reduce the levels of IL-6 and IL-8 in TNF-α-treated BEAS-2B cells in a dose-dependent manner.Hence,CR preparations and its cinnamic acid derivatives have the possibility to be developed as a complementary therapy in the treatment of respiratory system infection in clinics.  相似文献   
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