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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.
Oxidative stress is known to spark off the pathogenesis of cataract. Antioxidant potential of Abies pindrow Royle leaf extract (APE) is well established in the literature. In this context, standard aqueous leaf extract of this plant was evaluated for its role in hydrogen peroxide-induced cataract in isolated goat lenses using varying concentrations (5, 10, 15 and 20 mg/mL). Total phenol and flavonoidal content was evaluated and found to be high in concentration. Biochemical parameters, namely superoxide dismutase (SOD), glutathione (GSH), total protein content (TPC) and malondialdehyde (MDA), were evaluated. SOD, GSH and TPC formation was found to increase proportionally with increasing concentration. However, MDA level decreased significantly as the concentration of the extract increased. The results suggest that the extract under investigation can delay the onset and/or prevent the progression of cataract. Its anti-cataract potential may be attributed to the presence of high phenolics and flavonoids in APE. Photographic evaluation, further, confirmed the observation.  相似文献   
3.
A novel biflavanol with unique six connective hexacyclic rings, abiesanol A (1), was isolated from the aerial parts of Abies georgei together with four known flavanols. The structure of new compound was elucidated mainly by the analysis of 1D and 2D NMR spectroscopic data. In addition, single-crystal X-ray diffraction analysis was adopted to confirm the structure of abiesanol A (1). In biological assay for inhibitory activities against LPS-induced nitric oxide (NO) production in RAW264.7 macrophages, abiesanol A (1) showed potent effects at 50 μg/mL with the inhibition rate of 43.0%. Under the same concentration, abiesanol A (1) did not show any cytotoxicity against RAW264.7 macrophages.  相似文献   
4.
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   
5.
One new and 16 known compounds were isolated from Abies sibirica.Their structures were assigned mainly on the basis of NMR and MS spectroscopic data.In bioassay for anti-proliferative activity against four human tumor cells,compound 7 exhibited selective anti-proliferative activity against COLO-205 tumor cell with an IC50 value of 0.9μg/mL.  相似文献   
6.
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   
7.
Examination of daily catch–per–unit–effort (CPUE) information on Pacific halibut revealed sharp declines that could not be explained by natural and fishing mortality. Catchability may have decreased during a fishing period because of local depletions of fish, changes in fish behavior, and other causes. Mathematical models of CPUE with a short–term catchability function of time or effort were based on a generalization of the DeLury method. A method of standardization was developed to account for the length of a fishing period and to correct for catchability. The effort model was best for Pacific halibut data and the application showed that standardization of CPUE is necessary to have a valid index of abundance when short–term changes in catchability occur.  相似文献   
8.
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   
9.
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   
10.
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   
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