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61.
目的对卢旺达产金盏菊花的化学成分进行研究,为进一步开发利用该植物资源提供依据。方法采用大孔吸附树脂、正相硅胶、Sephadex LH-20、反相ODS等柱色谱以及制备型高效液相色谱法等手段进行分离纯化,并通过理化性质与核磁共振等波谱学数据相结合的方法鉴定化合物的结构。结果从金盏菊花体积分数为70%的乙醇溶液提取物中分离鉴定了6个单体成分,分别为异鼠李素-3-O-芸香糖苷(isorhamnetin-3-O-rutinoside,1)、异鼠李素-3-O-新橙皮糖苷(isorhamnetin-3-O-neohespeidoside,2)、香蒲新苷(typhaneoside,3)、槲皮素-3-O-β-D-新橙皮糖苷(quercetin-3-O-β-D-neohespeidoside,4)、芦丁(rutin,5)、槲皮素-3-O-(2″,6″-二-O-α-L-鼠李糖基)-β-D-葡萄糖苷(quercetin-3-O-(2″,6″-di-O-α-L-rhamnopyranosyl)-β-D-glucopyranoside,6)。结论首次对东非产金盏菊干燥花的化学成分进行研究,分离得到了6个黄酮类化合物。 相似文献
62.
HPLC法测定复方桔梗止咳片中甘草苷和甘草酸含量 总被引:1,自引:0,他引:1
目的:建立同时测定复方桔梗止咳片中甘草苷和甘草酸含量的HPLC检测方法。方法:采用Agilent C18(4.6 mm×150 mm,5μm)色谱柱;以乙腈-0.05%磷酸为流动相进行梯度洗脱;流速1.0 mL·min-1;检测波长237 nm;进样量:10μL;柱温30℃。结果:甘草苷、甘草酸分别在10.65~42.60 mg·L-1、97.30~389.30 mg·L-1范围内呈良好的线性关系,r分别为1.0000、1.0000;平均回收率(n=6)分别为98.80%(RSD=0.73%)、99.84%(RSD=0.10%)。测得6批复方桔梗止咳片,每片分别含甘草苷135.28μg、123.16μg、113.21μg、136.08μg、160.84μg、156.32μg,甘草酸441.36μg、405.86μg、364.69μg、446.93μg、518.22μg、509.65μg。结论:该方法简便,重复性好,可用于同时测定复方桔梗止咳片中甘草苷和甘草酸的含量。 相似文献
63.
目的:探讨肉苁蓉总苷( GCs)对阿尔茨海默病(AD)模型大鼠学习认知功能的影响及其作用机制。方法:
双侧脑室注射Aβ1-42 制备AD大鼠模型,连续给予模型大鼠不同剂量的GCs 腹腔注射20 d,Morris 水迷宫检测各
组大鼠空间学习记忆能力,尼氏染色观察海马CA1区细胞形态并计数正常锥体细胞;免疫组织化学测定脑组织突
触素( SYN)含量、酶联免疫吸附试验测定血清超氧化物歧化酶( SOD)和谷胱甘肽过氧化物酶( GSH-Px)活
性、丙二醛( MDA)的含量。结果:GCs 可明显缩短逃避潜伏期与上台前路程,明显增加目标象限时间百分比
与穿越平台次数;GCs 能提高海马CA1区锥体细胞的存活率,明显增加SYN蛋白的表达和提高SOD、GSH-Px 活
性,降低MDA的活性。结论:GCs 改善AD学习认知障碍的机制可能是通过减少自由基堆积、清除体内过多的
过氧化物,进而提高突触可塑性来改善学习认知功能。 相似文献
64.
Lipeng Wu Milen I. Georgiev Hui Cao Lutfun Nahar Hesham R. El-Seedi Satyajit D. Sarker Jianbo Xiao Baiyi Lu 《Medicinal research reviews》2020,40(6):2605-2649
Phenylethanoid glycosides (PhGs) are generally water-soluble phenolic compounds that occur in many medicinal plants. Until June 2020, more than 572 PhGs have been isolated and identified. PhGs possess antibacterial, anticancer, antidiabetic, anti-inflammatory, antiobesity, antioxidant, antiviral, and neuroprotective properties. Despite these promising benefits, PhGs have failed to fulfill their therapeutic applications due to their poor bioavailability. The attempts to understand their metabolic pathways to improve their bioavailability are investigated. In this review article, we will first summarize the number of PhGs compounds which is not accurate in the literature. The latest information on the biological activities, structure–activity relationships, mechanisms, and especially the clinical applications of PhGs will be reviewed. The bioavailability of PhGs will be summarized and factors leading to the low bioavailability will be analyzed. Recent advances in methods such as bioenhancers and nanotechnology to improve the bioavailability of PhGs are also summarized. The existing scientific gaps of PhGs in knowledge are also discussed, highlighting research directions in the future. 相似文献
65.
Mengyue Wang Min Zhang Qiyu Tang Xiaobo Li 《African journal of traditional, complementary, and alternative medicines》2012,9(2):189-196
In traditional Chinese medicine (TCM), licorice is usually processed with honey and traditionally used in decoction form. However, the influence of honey-roasting on the main pharmacological activities and the water-soluble active constituents of licorice has not been reported. The aim of the present study is to determine whether honey-roasting can modify the main pharmacological activities and the active constituents of licorice. According to licorice clinical application and processing method, the mainly related pharmacological activities of crude licorice, processed licorice and refined honey, such as enhancing immune function, relieving cough, eliminating phlegm and detoxication, were compared. The results showed that honey-roasting obviously reinforced the licorice activity of enhancing Pi-deficiency mice''s immune function, and significantly weaken the licorice activity of relieving cough, removing phlegm and detoxication. However, honey didn''t show the significant activity of relieving cough, removing phlegm and detoxication. The influence of honey-roasting on the chemical compositions in licorice slice and licorice decoction was investigated by using HPLC. The results showed that the content and the decocting quantity of mainly 5 active glycosides in licorice, i.e. liquiritin apioside, liquiritin, licuraside, isoliquiritin and glycyrrhizin, obviously changed after processing; glycyrrhizin and liquiritin obviously decomposed during honey-roasting. In conclusion, honey-roasting obviously modified the main pharmacological activities and the water-soluble compositions of licorice. The modification was not cause by honey only. This finding may shed some light on understanding the differences in the therapeutic values of crude and processed licorice. 相似文献
66.
Haruo Ogawa Takehiro Shinoda Flemming Cornelius Chikashi Toyoshima 《Proceedings of the National Academy of Sciences of the United States of America》2009,106(33):13742-13747
The sodium-potassium pump (Na+,K+-ATPase) is responsible for establishing Na+ and K+ concentration gradients across the plasma membrane and therefore plays an essential role in, for instance, generating action potentials. Cardiac glycosides, prescribed for congestive heart failure for more than 2 centuries, are efficient inhibitors of this ATPase. Here we describe a crystal structure of Na+,K+-ATPase with bound ouabain, a representative cardiac glycoside, at 2.8 Å resolution in a state analogous to E2·2K+·Pi. Ouabain is deeply inserted into the transmembrane domain with the lactone ring very close to the bound K+, in marked contrast to previous models. Due to antagonism between ouabain and K+, the structure represents a low-affinity ouabain-bound state. Yet, most of the mutagenesis data obtained with the high-affinity state are readily explained by the present crystal structure, indicating that the binding site for ouabain is essentially the same. According to a homology model for the high affinity state, it is a closure of the binding cavity that confers a high affinity. 相似文献
67.
目的:研究马鞭草化学成分。方法:利用色谱技术进行分离纯化,根据理化性质和波谱学数据进行结构测定。结果:从马鞭草乙醇提取物的正丁醇可溶部分得到4个苯乙醇苷类化合物,分别为异毛蕊花苷(1)、阿克替苷(2)、Parvifloroside B(3)和Campneoside Ⅰ(4);从石油醚可溶部分得到2个脂肪酸酯类化合物,分别为十六酸甲酯(5)和十六酸乙酯(6)。结论:化合物3和4为首次从该属植物中分离得到;5和6为首次从该植物中分离得到。 相似文献
68.
69.
目的 优选金匮肾气丸中苷类成分的提取工艺.方法 采用HPLC法测定马钱苷、芍药苷的量,紫外分光光度法测定总苷和总皂苷的量.以浸膏率、马钱苷、芍药苷、总苷和总皂苷的量为指标,按U9(95)均匀设计表设计试验,分别考察乙醇体积分数、液固比、煎煮时间和煎煮次数4个因素的影响.结果 通过DPS软件分析,得出苷类成分的最佳提取工艺为用14倍量58%乙醇煎煮3次,每次3 h,在此工艺提取得马钱苷和芍药苷的量分别为2.477 0、0.768 4 mg/g,以马钱苷计总苷的量为34.178 2 mg/g,以人参皂苷Re计总皂苷的量为4.910 8 mg/g.结论 均匀设计法优选出的金匮肾气丸中苷类成分的提取工艺合理可行,为金匮肾气丸的进一步研究提供参考. 相似文献
70.
LAWRENCE ONYANGO AROT Manguro JOSEPH ACHOLA Ogur DENNIS MAGIO Okora SAMUEL OTIENO Wagai PETER Lemmen 《Journal of Asian natural products research》2007,9(7):617-629
Five new iridoid glycosides characterised as 6-keto-8-acetylharpagide (1), 6,7-dehydro-8-acetylharpagide (2), 7,8-dehydroharpagide (3), 8-acetylharpagide-6-O-β-glucoside (4), harpagide-6-O-β-glucoside (5) together with three flavonol glycosides, myricetin 3-O-rutinoside-4'-O-rutinoside (6), myricetin 3-O-rutinoside-3'-O-rutinoside (7) and isorhamnetin 3-O-rutinoside-7-O-rutinoside-4'-O-β-glucoside (8) have been isolated from the aerial parts of Ajuga remota. Also isolated were two known compounds ajugarin IV and ajugarin V. Their structures were established using spectroscopic methods including UV, IR, FAB-MS, HR-MS, 1D and 2D NMR techniques. 相似文献