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1.
紫外分光光度法测定高山红景天根及其浸膏的有效成分   总被引:3,自引:0,他引:3  
使用紫外分光光度法测定了高山红景天根不同部位及其浸膏中主要有效成分的含量.红景天甙、酪醇对照品溶液和供试品溶液在276nm处具有最大吸收峰,红景天甙对照品溶液的线性回归方程为A=0.00529c+0.00189,r=0.99997(n=8),线性范围为7.97~71.71mg/L,平均回收率为98.08%,RSD为2.60%(n=5).测得高山红景天原药材内层部分、外皮层部分和总体混合物部分主要有效成分(红景天甙和酪醇)的含量(以红景天甙计)分别为2.789%,2.385%和2.617%,其浸膏中主要有效成分的质量分数分别为6.384%,13.80%和6.700%.并用HPLC法验证了该法的准确性,结果表明,该法可用于红景天属植物原药材及其浸膏中主要有效成分的定量分析.  相似文献   
2.
本文对高山红景天提取物中的一种新化合物进行了红外和拉曼光谱的测定,并对主要谱带进行了归属和讨论。  相似文献   
3.
Alzheimer’s disease (AD) is an age-related neurodegenerative disorder characterized by cognitive deficits, which are accompanied by memory loss and cognitive disruption. Rhodiola sachalinensis (RSE) is a medicinal plant that has been used in northeastern Asia for various pharmacological activities. We attempted to carry out the bioconversion of RSE (Bio-RSE) using the mycelium of Bovista plumbe to obtain tyrosol-enriched Bio-RSE. The objective of this study was to investigate the effects of Bio-RSE on the activation of the cholinergic system and the inhibition of oxidative stress in mice with scopolamine (Sco)-induced memory impairment. Sco (1 mg/kg body weight, i.p.) impaired the mice’s performance on the Y-maze test, passive avoidance test, and water maze test. However, the number of abnormal behaviors was reduced in the groups supplemented with Bio-RSE. Bio-RSE treatment improved working memory and avoidance times against electronic shock, increased step-through latency, and reduced the time to reach the escape zone in the water maze test. Bio-RSE dramatically improved the cholinergic system by decreasing acetylcholinesterase activity and regulated oxidative stress by increasing antioxidant enzymes (superoxide dismutase (SOD) and catalase (CAT)). The reduction in nuclear factor erythroid 2-related factor 2 (Nrf2)/heme oxygenase-1 (HO-1) signaling in the brain tissue due to scopolamine was restored by the administration of Bio-RSE. Bio-RSE also significantly decreased amyloid-beta 1–42 (Aβ1–42) and amyloid precursor protein (APP) expression. Moreover, the increased malondialdehyde (MDA) level and low total antioxidant capacity in Sco-treated mouse brains were reversed by Bio-RSE, and an increase in Nrf2 and HO-1 was also observed. In conclusion, Bio-RSE protected against Sco-induced cognitive impairment by activating Nrf2/HO-1 signaling and may be developed as a potential beneficial material for AD.  相似文献   
4.
硫酸化高山红景天多糖(RSASL)的制备及鉴定   总被引:11,自引:0,他引:11  
从高山红景天中分离出一种酸性杂多糖(RSA).该多糖由阿拉伯糖(Ara)、鼠李糖(Rha)、半乳糖(Gal)、木糖(Xyl)、葡萄糖(Glc) 与半乳糖醛酸(GalA)组成,其单糖摩尔比为1.00∶3 .23∶0 .26∶0 .34∶0 .84∶10.24.用氯磺酸-吡啶法制备硫酸化高山红景天多糖(RSASL).用离子色谱法测定RSASL 中S的质量分数为11.01% ,其硫酸基取代度为0.85.用红外光谱,紫外光谱,Sepharose CL-4B柱层析,激光解吸电离飞行时间质谱等方法鉴定,RSASL均显示了多糖硫酸酯的特征  相似文献   
5.
本文对高山红景天提取物中的一种新化合物进行了红外和拉曼光谱的测定 ,并对主要谱带进行了归属和讨论  相似文献   
6.
高山红景天系景天科红景天属草本植物,因其较好的疗效在医学上广泛应用.C24H30O8是一种从高山红景天中提取并已确认其结构的新的化合物.采用密度泛函理论(DFT)方法,在B3LYP/6-31G*水平下全优化得到了该化合物的分子几何构型和电子结构;依据Onsager自恰反应场(SCRF)模型考察了其在氯仿、丙酮、二甲亚砜及水等溶剂中的溶剂化作用;基于气相优化结构进行了B3LYP/6-31G*振动分析,用0.9613校正后的主要红外光谱与实验符合得很好.进一步按照统计力学原理求得了298~1000 K温度范围内该化合物的标准热力学函数(焓,熵,热容).  相似文献   
7.
不同产地红景天药材中红景天甙含量的测定   总被引:3,自引:0,他引:3  
以红景天甙含量为指标建立了红景天药材的HPLC定量分析方法.色谱条件:C18柱(250 mm×4.6 mm,25μm),甲醇-乙腈-水为流动相梯度洗脱,检测波长为275 nm.该法灵敏度高,重现性好.利用本方法对六种不同产地红景天药材中红景天甙的含量进行了分析比较.结果表明,产地不同,红景天甙的含量差别很大,其中以云南丽江地区产的含量最高.  相似文献   
8.
The objective of the present study is to develop a method for large-scale separating and purifying salidroside from rhodiola kirilowii roots and for preparing injectable medicinal ingredient.Crude extract of salidroside was prepared by water-ethanol system,and purified by column chromatography of macroporous resins.Static adsorption and desorption studies were performed on six kinds of macroporous resins,and SP825 resin was chosen,followed by optimizing process parameters.The optimum sample volume,feed concentration,ratio of diameter to height,and feeding flow rate were 1.5 bed volumes(BV),15 mg/mL,1:10 and 1 BV/h,respectively.Dynamic desorption was performed consecutively with 8 BV of distilled water,3 BV of 5% ethanol and 8 BV of 10% ethanol at a flow rate of 2 BV/h.After three cycles in separating 3.5 tons of rhodiola kirilowii roots,salidroside purity was increased from 3.4% in the crude extract to 93.6% in purified salidroside product.This study provides a novel method to separate salidroside for injectable use.  相似文献   
9.
熊伟  陈开勋  郑岚  杨立  刘涛  姜波 《化学研究》2007,18(3):91-94
探讨了西藏红景天的超临界流体萃取工艺,应用GC-MS方法对萃取物成分进行了分析.结果表明,最佳提取工艺条件为:夹带剂乙醇的体积分数为85%,萃取温度为55℃,萃取压力为30 MPa,萃取时间为2 h.此条件下红景天萃取物得率为5.65%.GC-MS分析鉴定出32种组分,主要为醇类、酯类、烷烃、烯烃等化合物,并应用峰面积归一化法测定了其相对含量.  相似文献   
10.
The continuous chemical investigation on the ethyl acetate (EtOAc) soluble fraction of the MeOH extract afforded two new lanostane triterpenoid derivatives including one with a rearranged lanostane skeleton. They were identified as 3,4-seco-8-(14→,13R)abeo-17,13-friedo-9β-lanosta-4(28), 7,14(30),24-tetraen-26,23-olide-23-hydroxy-3-oic acid (1) and 7,14-mariesa-dien-3a-hydroxy-25-methoxy-26-oic acid (2). Structural determination of these compounds were carried out by the spectral studies especially by the two digital (2D)-NMR and high-resolution MS experiences.  相似文献   
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