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1.
从蛇足石杉中超声提取石杉碱甲和石杉碱乙   总被引:12,自引:1,他引:11  
用正交试验确立了超声提取蛇足石杉生物碱的最佳条件。以石杉碱甲和石杉碱乙回收率为指标,考察了溶剂倍数、溶剂浓度、超声时间、超声功率等因素的影响。结果表明,在室温下超声提取的最优条件为:酸浓度O.8%(v/v),液固比例20:1,超声功率600W,超声15min。三次重复实验所得石杉碱甲和石杉碱乙回收率分别是9r7.3%和93.5%,相对标准偏差分别为1.31%和1.40%(n=3)。与传统的回流提取工艺相比,过程时间从2h缩短为15min,回收率提高了10%以上。  相似文献
2.
石杉碱甲提取工艺研究   总被引:12,自引:0,他引:12  
以蛇足石杉为原料,采用生物碱分离的传统方法,通过盐酸浸提,氯仿萃取来制取、纯化石杉碱甲,选出最佳、最经济的生产工艺配方是:料液比为1:10,浸泡10 h,酸解3次,每次为45 min,酸解pH值为3.0,酸解温度为55℃,碱化pH为9.0;纯化过程中,用相当于石杉碱甲溶液体积15%的活性炭在pH为3.0条件下除杂,石杉碱甲的得率大于79.4%。  相似文献
3.
从千层塔中微波协助提取石杉碱甲和石杉碱乙   总被引:6,自引:0,他引:6       下载免费PDF全文
首先从 8种溶剂中筛选出硫酸作为微波协助提取的浸提溶剂 ,然后用正交试验确立了千层塔生物碱的最佳提取条件。以石杉碱甲和石杉碱乙回收率为指标 ,考察了溶剂倍数、溶剂浓度、微波处理时间等因素。结果表明 ,在室温下微波协助提取的最优条件为 :酸浓度 0.8% (v/v) ,液固比例 2 5∶1 ,微波处理时间 90s。 3次重复实验所得石杉碱甲和石杉碱乙回收率分别是 93.7%和 93.9% ,相对标准偏差分别为 1.79%和 1.5 6% (n =3)。与传统的回流提取工艺相比 ,过程时间从 2h缩短为 90s,回收率提高了 1 0 %以上。  相似文献
4.
Ma X  Gang DR 《Phytochemistry》2008,69(10):2022-2028
Alzheimer's disease (AD) is growing in impact on human health. With no known cure, AD is one of the most expensive diseases in the world to treat. Huperzine A (HupA), a anti-AD drug candidate from the traditional Chinese medicine Qian Ceng Ta (Huperzia serrata), has been shown to be a powerful and selective inhibitor of acetylcholinesterase and has attracted widespread attention because of its unique pharmacological activities and low toxicity. As a result, HupA is becoming an important lead compound for drugs to treat AD. HupA is obtained naturally from very limited and slowly growing natural resources, members of the Huperziaceae. Unfortunately, the content of HupA is very low in the raw plant material. This has led to strong interest in developing sources of HupA. We have developed a method to propagate in vitro tissues of Phlegmariurus squarrosus, a member of the Huperziaceae, that produce high levels of HupA. The in vitro propagated tissues produce even higher levels of HupA than the natural plant, and may represent an excellent source for HupA.  相似文献
5.
石杉碱甲结构改造的研究进展   总被引:1,自引:0,他引:1  
石杉碱甲是高效、高选择性的可逆性乙酰胆碱酯酶抑制剂,是治疗早老性痴呆症的一个有前景的药物.本文概述了石杉碱甲的性质、结构和构效关系,从结构简化、C10、吡啶酮环、脂桥环、环外双键和桥头氨基等方面综述了石杉碱甲结构改造的研究进展,并描述了所得的新型石杉碱甲类似物的抗乙酰胆碱酯酶的生物活性.在已合成的大量的石杉碱甲类似物中,部分类似物的活性优于天然石杉碱甲,石杉碱甲结构改造的研究取得了可喜的进展.  相似文献
6.
千层塔内生真菌SHB发酵产石杉碱甲条件的研究   总被引:1,自引:0,他引:1  
为提高千层塔产黄青霉属内生真菌SHB液体发酵产石杉碱甲的产量,通过单因子和正交试验研究了真菌SHB液体发酵的条件。结果表明,千层塔内生真菌SHB液体发酵产石杉碱甲的适宜条件:温度为28℃,起始pH为6.4,接种量为12%,种龄为48h,转速为160r/min,发酵时间为8d。在此条件下,石杉碱甲的产量可达4.761μg/mL。  相似文献
7.
Huperzine A (HupA), a novel Lycopodium alkaloid isolated from Chinese folk medicine Huperzia serrata (Qian Ceng Ta), is a potent, selective and well-tolerated inhibitor of acetylcholinesterase (AChE). It has been proven to significantly improve the learning and memory impairment in Alzheimer's disease (AD) and vascular dementia (VaD) patients in China. Interestingly, our recent data indicate that HupA also possesses other protective functions. This paper will give an overview on the protective effects of HupA, which includes regulating beta-amyloid precursor protein (APP) metabolism, protecting against Abeta-mediated oxidative stress, apoptosis and mitochondrial dysfunction, as well as anti-inflammation. The multiple neuroprotective effects of HupA might yield additional beneficial effects in AD and VaD therapy.  相似文献
8.
9.
影响九华山千层塔石杉碱甲含量的主要环境因子分析   总被引:1,自引:1,他引:0  
为了确定九华山千层塔[Huperzia serrata(Thunb.)Trev.]的最佳采收期和采收部位,根据千层塔不同部位的石杉碱甲含量及各环境因子的变化趋势,运用灰色关联分析法对影响九华山千层塔石杉碱甲含量的主要环境因子进行了分析。结果表明,千层塔各部位的石杉碱甲含量不同,其中根中的含量最低,叶和茎中的含量较高;4月份叶和茎中的石杉碱甲含量最高,分别为0.0559%和0.0444%。影响九华山千层塔石杉碱甲含量的主要环境因子是根际土壤有机质含量、全氮含量和全磷含量,温度和降水量与石杉碱甲含量变化的相关性最小。研究结果表明,在九华山,千层塔的最佳采收期为4月份,最佳采收部位是叶和茎。  相似文献
10.
1. Acetylcholinesterase (AChE, EC 3.1.1.7) and butyrylcholinesterase (BuChE, EC 3.1.1.8) are serine hydrolase enzymes that catalyze the hydrolysis of acetylcholine.2. (–) Huperzine A is an inhibitor of AChE and is being considered for the treatment of Alzheimer's disease.3. In addition to esterase activity, AChE and BuChE have intrinsic aryl acylamidase activity.4. The function of aryl acylamidase is unknown but has been speculated to be important in Alzheimer pathology.5. Kinetic effects of (–) huperzine A and ( ±)$ huperzine A on the aryl acylamidase activity of human cholinesterases were examined.6. (–) Huperzine A inhibited the aryl acylamidase activities of both AChE and BuChE.7. (±) Huperzine A inhibited this function in AChE but stimulated BuChE aryl acylamidase suggesting that the (+) enantiomer is a powerful activator of this enzyme activity.8. The two huperzine enantiomers may prove to be useful tools to examine the function of aryl acylamidase activity, including its role in Alzheimer pathology.  相似文献
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