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31.
Kirmizibekmez H Ariburnu E Masullo M Festa M Capasso A Yesilada E Piacente S 《Fitoterapia》2012,83(1):130-136
From the MeOH extract of Sideritis trojana, a new iridoid glycoside, 10-O-(E)-feruloylmelittoside (1) was obtained in addition to four known iridoid glycosides [melittoside (2), 10-O-(E)-p-coumaroylmelittoside (3), stachysosides E (4) and G (5)]. Moreover, five phenylethanoid glycosides [verbascoside (6), isoacteoside (7), lamalboside (8), leonoside A (9), isolavandulifolioside (10), three flavone glycosides (isoscutellarein 7-O-[6'-O-acetyl-β-allopyranosyl-(1→2)]-β-glucopyranoside (11), 4'-O-methyisoscutellarein 7-O-[6'-O-acetyl-β-allopyranosyl-(1→2)]-β-glucopyranoside (12), 3'-hydroxy-4'-O-methyisoscutellarein 7-O-[6'-O-acetyl-β-allopyranosyl-(1→2)]-β-glucopyranoside (13) and a benzylalcohol derivative (di-O-methylcrenatin) were obtained and identified. The structures were elucidated on the basis of NMR and HRMS data. All compounds were tested for their antioxidant activity by in vitro TEAC assay and some of them exhibited moderate activity (0.97-1.44 mM) when compared with the reference compound (quercetin 1.86 mM). Glycosides 6-13, the most active compounds in the TEAC assay, were also tested by flow cytometry to evaluate their ability to affect the levels of reactive oxygen species (ROS) in human prostate cancer cells (PC3). 相似文献
32.
Crude ethanol extracts from Ficus benjamina leaves strongly inhibit Herpes Simplex Virus 1 and 2 (HSV-1/2) as well as Varicella Zoster Virus (VZV) cell infection in vitro. Bioassay-guided fractionation of the crude extract demonstrated that the most efficient inhibition of HSV-1 and HSV-2 was obtained with the flavonoid fraction. The present study was aimed to further isolate, purify and identify substances with potent antiviral activity from the flavonoid fraction of F. benjamina extracts. Flavonoids were collected from the leaf ethanol extracts through repeated purification procedure and HPLC analysis. The antiviral activity of each substance was then evaluated in cell culture. Three known flavone glycosides, (1) quercetin 3-O-rutinoside, (2) kaempferol 3-O-rutinoside and (3) kaempferol 3-O-robinobioside, showing highest antiviral efficiency were selected and their structure was determined by spectroscopic analyses including NMR and mass spectrometry (MS). These three flavones were highly effective against HSV-1 reaching a selectivity index (SI) of 266, 100 and 666 for compound 1, 2 and 3, respectively, while the SI of their aglycons, quercetin and kaempferol amounted only in 7.1 and 3.2, respectively. Kaempferol 3-O-robinobioside showed similar SI to that of acyclovir (ACV), the standard anti-HSV drug. Although highly effective against HSV-1 and HSV-2, these flavone glycosides did not show any significant activity against VZV. 相似文献
33.
Perrone A Capasso A Festa M Kemertelidze E Pizza C Skhirtladze A Piacente S 《Fitoterapia》2012,83(3):554-562
Two new compounds, a furostanol glycoside (1) and a pregnane glycoside (4), along with eight known compounds, belonging to the classes of spirostane (2,3), pregnane (5–7) and cardenolide (8–10) glycosides, were isolated from the seeds of Digitalis ciliata. Their structures were elucidated by 1D and 2D-NMR experiments as well as ESI-MS analysis. For the first time pregnane glycosides of the diginigenin series have been isolated from D. ciliata. The cytotoxic effects of compounds 1–10 on cell viability of several cancer cell lines, namely human breast cancer (MCF-7), human glioblastoma (T98G), human lung adenocarcinoma (A549), human colon carcinoma (HT-29), and human prostate cancer (PC-3) cell lines were evaluated. Compounds 1, 4, 7 and 8 showed antiproliferative effects against MCF-7, HT-29 and A549 cancer cells with IC50 values ranging from 8.3 to 20 μM. The effects of compounds 1–10 on cell proliferation were evaluated on these three cancer cell lines by cell cycle analysis of DNA content using flow cytometry. Compounds 7, 8 and 10 induced significant changes in G2/M cell cycle phase of all analyzed cells. The obtained results indicate that compounds 7, 8 and 10 are cytostatic compounds effective in reducing cell proliferation by inducing accumulation of the cells in the G2/M phase of the cell cycle. 相似文献
34.
用闪式硅胶柱层析分离纯化银杏叶中有效成分黄酮醇苷和萜类内酯工艺条件的优选。用不同极性溶剂(乙醚、乙酸乙酯、丙酮、乙醇)对加样品后的闪式硅胶层析柱进行洗脱,收集洗脱液,采用高效液相色谱法分别测定每份洗脱液中黄酮醇苷和萜类内酯的含量,从而筛选出应用闪式硅胶柱层析时,最佳的洗脱液种类和用量为:萜类内酯用3倍床体积的乙酸乙酯洗脱,黄酮醇苷用4倍床体积的丙酮洗脱即得。 相似文献
35.
新疆药桑黄酮和多酚的提取与分析研究初报 总被引：5，自引：0，他引：5
本文采用有机溶剂提取技术和分光光度法．对新疆药桑桑果、叶片和枝条等不同器官的黄酮、多酚类化合物进行提取和测试分析,研究结果表明：新疆药桑同一株树体桑果、叶片和枝条等不同器官间的黄酮和多酚类化合物的含量存在着显著差异,其中叶片黄酮和多酚类含量最高、枝条次之、桑果中最低;研究目的为新疆药桑桑叶,桑枝,桑椹的药用功效机理研究和开发利用提供理论依据。 相似文献
36.
在黑龙江绥棱和内蒙磴口试验区对俄罗斯11个大果沙棘品种和蒙古1个大果沙棘品种的果实特性进行了比 较研究,结果表明:(1)黑龙江绥棱试验点百果质量在38．33-67．59 g之间,磴口试验点为32．87-63．85 g。在供 试的品种中除卡图尼在2个试验点百果质量一致外,其余品种百果质量在磴口试验点均比绥棱试验点有不同程度 的下降。引进品种除阿尔泰新闻外,其余品种的百果质量均显著低于原产地俄罗斯,反映出百果质量随纬度下降而 下降的趋势。(2)不同品种果实横径与纵径呈紧密线性相关,即随着果实纵径的增大横径随之增大。(3)果实纵 径、横径、长宽比三个指标与百果质量均达到极显著线性相关,因此可根据果实形状指标对百果质量进行预测。 (4)供试的11个大果沙棘品种果汁Vc含量在342．6-1770．3 mg·kg-1之间,与俄罗斯原产地Vc含量(470- 3300mg·kg-1)相比均有不同程度的下降。(5)供试大果沙棘品种浆果果汁中VE含量在4-29 mg·kg-1之间。 总黄酮在36-429 mg·kg-1之间,其中槲皮素、山奈酚和异鼠李素分别为21．9-310．8 mg·kg-1、1．0-9．8 mg· kg-1和13．1-133．8 mg·kg-1,很明显总黄酮主要由槲皮素和异鼠李素组成,而且二者的含量比较接近。 相似文献
37.
风箱果叶色变化及呈色机理研究 总被引：1，自引：1，他引：0
为研究风箱果叶片不同生长发育过程中叶色变化及呈色机理的问题,以风箱果、‘金叶’风箱果、‘紫叶’风箱果为材料,对其叶片从幼嫩到成熟转变过程5 个生长阶段的叶部特征和叶色变化进行比较研究,并采用徒手切片法观察叶片中色素空间分布。结果表明,随着3 种风箱果的生长,叶片面积均呈逐渐增大的趋势,‘紫叶’风箱果叶面积最大;3 种风箱果叶绿素a 含量、叶绿素b 含量、叶绿素/类胡萝卜素均呈现逐渐升高的趋势,风箱果不同生长阶段叶绿素a 含量、叶绿素b 含量均显著高于‘紫叶’风箱果和‘金叶’风箱果;3 种风箱果叶片色素均主要分布于栅栏组织内,在海绵组织和表皮细胞分布较少。上述结果明确了风箱果叶片在生长发育过程中的叶部特征和叶色表现,为其科学合理应用提供了理论依据。 相似文献
38.
Ioannis Vasilakoglou Dimitrios Kalfountzos Nikolaos Gougoulias Charalampos Reppas 《Archives of Agronomy and Soil Science》2016,62(4):457-472
A 3-year field study was conducted in central Greece to determine the productivity of two stevia [(Stevia rebaudiana (Bertoni) Bertoni] varieties (‘Morita’ and ‘Candy-stevia’) under normal and reduced irrigation (100% and 75% of the evapotranspiration) and fertilization [1:0.8:1.1 or 1:0.4:0.8 N:P:K ratio in the first year and only N fertilization (100% or 74% of the recommended rate) in the second and third years] inputs. Averaged across years, stevia cv. Morita achieved greater dry leaf yield (3.48 t ha?1) than the cv. Candy-stevia (2.85 t ha?1). Irrigation and fertilization inputs did not significantly affect stevia cv. Morita dry leaf and steviol glycosides (stevioside plus rebaudioside-A) yields; however, decreasing irrigation and fertilization caused slight reduction of cv. Candy-stevia yields. In cv. Morita leaves, the concentrations of stevioside and rebaudioside-A ranged from 5.97% to 7.78% and 3.73% to 4.79%, respectively, while the corresponding concentrations in cv. Candy-stevia leaves were 8.21–9.36% and 3.89–6.33%. Conclusively, both stevia varieties could achieve satisfactory dry leaf biomass and steviol glycosides yield, even when grown under reduced irrigation (at 75% of evapotranspiration) and reduced N fertilization (74% of the recommended rate). Thus, stevia could represent an alternative crop to tobacco in the Mediterranean conditions. 相似文献
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