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1.
银杏叶和山楂叶的抗氧化作用   总被引:42,自引:3,他引:42       下载免费PDF全文
 目的:研究银杏叶、山楂叶提取物的抗氧化作用。方法:采用荧光法测定过氧化作用的产物丙二醛含量;分光光度法测定银杏叶、山楂叶提取物对氧自由基(H2O2,O2)的抑制作用。结果:银杏叶(G)、山楂叶(H)的提取物能抑制小鼠肝匀浆在37℃温育下生成的丙二醛,抑制率G为68.5%,H为76.9%。抑制由邻苯三酚在pH8.4自氧化产生的O2(与对照组相比,G:P<0.01、H:P<0.05),并能降低由H2O2所致的血红蛋白氧化和红细胞的溶血作用(溶血率H2O2为10.9%,经G和H抗氧化作用后分别为5.7%和9.2%)。结论:银杏叶、山楂叶提取物对氧自由基具有强的抑制作用。  相似文献   

2.
头花蓼对α-葡萄糖苷酶的抑制活性研究   总被引:3,自引:3,他引:0  
目的 :研究头花蓼不同溶剂提取物对 α -葡萄糖苷酶的抑制活性。 方法 :采用索氏提取法对头花蓼进行不同溶剂提取,以体外法测定各提取物对 α- 葡萄糖苷酶的抑制作用。 结果: 头花蓼各提取物均具有较好的 α -葡萄糖苷酶抑制活性。其中头花蓼的甲醇提取物抑制活性最高(IC50 1.68 μg·mL-1),乙酸乙酯提取物(IC50 7.27 μg·mL-1)和石油醚提取物(IC50 116.81 μg·mL-1)的活性次之。3个提取物活性均远大于阳性对照acarbose(IC50 1 081.27 μg·mL-1)。且各提取物对 α- 葡萄糖苷酶的抑制作用均具有剂量依赖性。 结论: 头花蓼甲醇提取物对 α- 葡萄糖苷酶活性的抑制效果非常显著,具有很好的开发价值。  相似文献   

3.
目的:研究冠突散囊菌体外抗氧化活性。方法:采用萃取法对冠突散囊菌甲醇提取物萃取获得石油醚,乙酸乙酯和正丁醇3种提取物,并以维生素C(VC)为阳性对照,用清除二苯代苦味酰基(DPPH)自由基和(ABTS)自由基测定法,对冠突散囊菌3种提取物抗氧化活性进行测定。结果:冠突散囊菌石油醚提取物清除 DPPH和ABTS+自由基半数清除浓度(IC50)分别为0.078,0.083 g·L-1 ,乙酸乙酯提取物IC50分别为0.21,0.13 g·L-1;正丁醇提取物对DPPH和ABTS+自由基几乎没有清除作用;3种提取物清除DPPH和ABTS+自由基的能力均比阳性对照VC(IC50分别为0.032,0.024 g·L-1)弱。结论:冠突散囊菌石油醚和乙酸乙酯提取物均具有抗氧化活性,且石油醚提取物活性较强。  相似文献   

4.
目的:研究新疆鼠尾草总酚酸提取物和纯化物的体外抗氧化活性。方法:以40%乙醇提取和大孔吸附树脂纯化分别制备得到新疆鼠尾草总酚酸的提取物和纯化物,以维生素C(VC)为对照,通过体外化学模拟方法测定新疆鼠尾草总酚酸提取物和纯化物的还原能力、对·DPPH自由基、羟基自由基(·OH)和超氧自由基(O2-·)的清除能力,研究新疆鼠尾草总酚酸的抗氧化活性。结果:新疆鼠尾草总酚酸提取物和纯化物清除·DPPH自由基的作用50%清除浓度(IC50,分别为0.029,0.039 g·L-1)弱于VC(IC500.018 g·L-1);对羟基自由基(·OH)的清除作用(IC50分别为0.212,0.165 g·L-1)强于VC(IC500.356 g·L-1);对超氧自由基(O2-·)的清除能力(IC50分别为3.735,1.913 g·L-1)弱于VC(IC500.390 g·L-1),其纯化物还具有一定的还原能力。结论:新疆鼠尾草总酚酸具有较强的抗氧化作用。  相似文献   

5.
目的 :观察四逆汤提取物 (DRE)及其组方药提取物对低氧条件下大鼠血管内皮细胞释放血栓素A2(TXA2 )、前列环素 (PGI2 )和一氧化氮 (NO)的影响。方法 :低氧处理的大鼠血管内皮细胞经四逆汤及其组方药提取物作用后 ,取条件培养液 ,采用放射免疫法及Griess反应测定培养液中的PGI2 ,TXA2 和NO的代谢产物 6 酮 前列腺素F(6-keto-PGF) ,血栓素B2 (TXB2 )及亚硝酸盐 (NO2 -)含量。结果 :与对照组比较 ,DRE、甘草提取物 (LE)、干姜提取物 (GE)、附子提取物 (AE)、甘草加附子提取物 (ALE)、干姜加附子提取物 (AGE)可以显著增加低氧处理的大鼠血管内皮细胞培养液中 6-keto-PGF的含量及 6-keto-PGF/TXB2 的比值 ,但对TXB2 的含量没有显著影响。DRE组对 6-keto-PGF含量的影响显著高于LE ,GE ,AE ,ALE ,AGE组。DRE组对 6-keto-PGF/TXB2 比值的影响显著高于GE ,AE ,ALE组。与对照组比较 ,DRE ,LE ,GE ,AE ,AGE ,ALE组显著提高血管内皮细胞培养液中NO2-的含量。DRE的药理作用显著高于GE ,AE ,ALE组。结论 :四逆汤提取物增加低氧处理的大鼠血管内皮细胞培养液中NO ,PGI2含量及PGI2 /TXA2 的比值。四逆汤提取物的药理作用强于组方药提取物。  相似文献   

6.
吴茱萸水和70%乙醇提取物的急性毒性和遗传毒性试验   总被引:3,自引:1,他引:2  
杨秀伟 《中国中药杂志》2008,33(11):1317-1321
目的:研究吴茱萸水和70%乙醇提取物的急性毒性和致突变性。方法:采用霍恩氏法研究灌胃给予小鼠吴茱萸水和70%乙醇提取物的半数致死量(LD50)。选用健康昆明种小鼠40只,雌雄各半,体重17~22 g,随机分为4个受试药物剂量组:1.00,2.15,4.64,10.00 g·kg-1,灌胃给药,观察7 d,记录中毒和死亡情况,计算得出LD50。采用鼠伤寒沙门菌回复突变试验(Ames试验) 研究其致突变性,小鼠精子畸变试验和小鼠骨髓细胞微核试验研究其致畸变性。结果:小鼠口服吴茱萸水和70%乙醇提取物的LD50大于10.0 g·kg-1;2种提取物各剂量组小鼠灌胃后未见明显中毒症状,亦无死亡。2种提取物的Ames试验阴性、未发现对小鼠精子产生畸变作用、对小鼠骨髓细胞染色体未见损伤。在急性毒性、小鼠精子畸变和小鼠骨髓细胞微核试验中,从试验开始到结束,小鼠体重增重情况良好。结论:吴茱萸水和70%乙醇提取物对小鼠属实际无毒,LD50大于10.0 g·kg-1;在本试验条件下,未发现其有遗传毒性。  相似文献   

7.
逍遥散超临界CO2提取工艺及提取物GC-MS特征图谱初步研究   总被引:2,自引:2,他引:0  
该文为了初步确定逍遥散超临界CO2提取的最佳工艺条件,并建立提取物的气相色谱-质谱(GC-MS)特征图谱,以提取物得率为考察指标,采用正交试验设计方法,对提取压力、提取温度、CO2流量、提取时间等因素进行考察;采用GC-MS对不同批次的提取物进行特征图谱分析。逍遥散超临界CO2提取的最佳工艺条件为提取压力20 MPa,提取温度50 ℃,CO2流量25 kg·h-1,提取时间3 h,提取物平均得率2.2%。GC-MS特征图谱中确定27个共有峰,占总峰面积的81.89%,其中指认出21个化合物,占提取物总量的53.20%。超临界CO2萃取工艺合理可行,GC-MS方法准确可靠,重复性好,可用于逍遥散超临界CO2提取物的制备及质量控制。  相似文献   

8.
埃及药用植物中抗人类免疫缺陷病毒药物的研究   总被引:6,自引:0,他引:6  
对来自埃及的97种药用植物的天然植物及其甲醇提取物和水提取物的抑制逆转录 (RT)酶和抑制HIV 1诱导的细胞病理作用 (CPE)进行体外评价。余甘子Phyllanthu semblica L .果实的甲醇提取物显示出很强的抑制HIV-1的RT作用 ,其 50%抑制浓度 (IC50)值为 9μg·mL-1。对甲醇提取物通过生物活性导向分级分离 (bioactivi ty guidedfractionation)得到抑制性有效物质PutranjivainA (PA) ,其IC50 值为 3.9μm。巴豆Crotontiglium种子的水提物和甲醇提取物可以显著的抑制传染性和HIV 1诱导的MT 4细胞的CPE ,它们的IC50 值分别为 0.0 25μg·mL-1和 2.0μg·mL-1,且均低于产生细胞毒性的浓度 (选择性指数分别为 34.4和50.0)。通过生物活性导向分级分离 ,从甲醇提取物中分离得到 8种佛波醇酯 ,对它们抑制HIV-1诱导的MT-4细胞的CPE的活性进行评价。发现 12O 十四 (烷 )酰佛波醇-13-乙酸酯 (TPA)既是HIV-1诱导的CPE的抑制剂 (IC100值为 0.4 8ng·mL-1) ,又是PKC的活化剂。另证明 ,12O-乙酰佛波醇-13-癸酸酯 (APD)有抗HIV-1的作用 (IC100 值为 7.6ng·mL-1) ,但没有PKC的活化作用。  相似文献   

9.
目的: 研究阿育魏实不同提取物对酪氨酸酶活性和黑色素生成的影响。 方法: 以阿育魏实为材料,通过乙醇提取得到总提取物即醇提物,然后依次用石油醚、三氯甲烷、乙酸乙酯、正丁醇萃取,得到相应的提取物。采用蘑菇酪氨酸酶多巴速率氧化法和NaOH裂解法研究了该提取物对酪氨酸酶的效应和黑色素上调率。 结果: 所得阿育魏实乙醇和乙酸乙酯提取物对酪氨酸酶激活作用较明显,对黑色素生成具有直接刺激作用,与对照品补骨脂和驱虫斑鸠菊相比,阿育魏实乙酸乙酯提取物IC50为(13.64±7.78) g·L-1,对酪氨酸酶激活作用优于临床治疗白癜风药物补骨脂[IC50 (21.18±2.88) g·L-1]。 结论: 阿育魏实乙酸乙酯提取物具有较好的体外酪氨酸酶激活及促进黑色素生成作用,可为临床治疗白癜风药物提供依据。  相似文献   

10.
目的:探讨黄皮叶提取物对哮喘大鼠炎症反应中Th1/Th2细胞因子平衡的调节作用。方法:将健康雄性SD大鼠48只,随机分为6组,分别为正常组、哮喘模型组、地塞米松组(1.5 mg·kg-1·d-1)、黄皮叶提取物低、中、高剂量组(520,1 040,2 080 mg·kg-1·d-1)。除正常组外,其余各组分别在第1,7天采用卵清蛋白致敏法ih致敏液,并于第15天开始,各给药组大鼠每天在灌胃给药后1 h进行雾化激发,连续1周;正常组及模型组以生理盐水灌胃代替。分别采用ELISA法测定大鼠血清中一氧化氮(NO),白三烯D4(LTD4),白细胞介素-4(IL-4),γ-干扰素(IFN-γ)的含量、硝酸还原法测肺组织NO含量;RT-PCT法测定肺组织中IL-4,IFN-γ mRNA表达及观察肺组织病理学改变。结果:与正常组比较,模型组大鼠血清中NO,IL-4,LTD4的含量明显升高,IFN-γ的含量降低,肺组织NO含量明显升高,大鼠肺组织中IL-4 mRNA表达明显升高,IFN-γ mRNA表达明显降低(P<0.01);与模型组比较,黄皮叶提取物低、中、高剂量组均能明显减少血清中NO,IL-4的含量,升高IFN-γ的含量(P<0.05,P<0.01),黄皮叶提取物高、中剂量组能减少哮喘大鼠肺组织中NO的含量,黄皮叶提取物高剂量组能明显减少哮喘大鼠血清中LTD4的含量(P<0.05,P<0.01),黄皮叶提取物低、中、高剂量组能明显降低哮喘大鼠肺组织中IL-4 mRNA表达,增加IFN-γ mRNA表达(P<0.05,P<0.01)。结论:黄皮叶提取物能有效的减少哮喘大鼠的炎症反应,其机制可能是通过调节Th1/Th2细胞因子的平衡,从而减轻炎症细胞浸润有关。  相似文献   

11.
周欣  张琳  毛婵  康希  曲彤  王云红  杨荣平 《中草药》2019,50(9):2194-2200
目的建立陈皮饮片HPLC指纹图谱分析方法,为其质量控制提供技术参考。方法采用HPLC法建立17批陈皮饮片的指纹图谱,通过聚类分析(clusteranalysis,CA)、主成分分析(principalcomponentanalysis,PCA)、正交偏最小二乘判别分析(orthogonal partial least square discrimina te analysis,OPLS-DA)对指纹图谱进行评价。结果建立了陈皮饮片指纹图谱,相似度均0.9,确定了25个共有峰,其中14个峰的变量投影重要性(variableimportance projection,VIP)均1,通过与对照品谱图比对,确定了13号峰为芸香柚皮苷、14号峰为橙皮苷、23号峰为川陈皮素、24号峰为3,5,6,7,8,3′,4′-七甲氧基黄酮、25号峰为桔皮素。结论该方法简单可靠,可用于陈皮饮片鉴别和质量控制。  相似文献   

12.
  目的:考察柑橘不同用药部位——橘核、橘络和陈皮中橙皮苷、柠檬苦素及诺米林的含量与其抗氧化和抗乳腺癌活性的相关性  方法:通过HPLC法检测来自不同产地的橘核、橘络和陈皮药材中橙皮苷、柠檬苦素及诺米林的含量,结合体外DPPH和FRAP抗氧化实验方法以及MTT法研究3种成分的含量差异对药材抗氧化活性和抑制乳腺癌细胞MCF-7增殖作用的影响  结果:橙皮苷含量:陈皮>橘络>橘核;柠檬苦素类物质含量:橘核>橘络>陈皮;体外抗氧化活性:陈皮>橘络>橘核;抑制乳腺癌细胞增殖作用:橘核>橘络>陈皮  结论:橘核、橘络和陈皮的抗氧化活性强弱主要与橙皮苷含量相关,而三者的抗乳腺癌活性强弱主要与其柠檬苦素和诺米林含量相关。  相似文献   

13.
The antiproliferative activities of aqueous and organic extracts prepared from 26 Hungarian species of the tribes Cynereae and Lactuceae (Asteraceae) were tested in vitro against HeLa (cervix epithelial adenocarcinoma), A431 (skin epidermoid carcinoma) and MCF7 (breast epithelial adenocarcinoma) cells by using the MTT assay. Of the tested 200 extracts of different plant parts obtained with n‐hexane, chloroform, 50% methanol and water, 16 extracts displayed noteworthy cell growth inhibitory activity (>50% inhibition at a concentration of 10 µg/mL). The IC50 values of these extracts were determined, and their direct cytotoxic effects were measured. High differences between the antiproliferative and cytotoxic activities, demonstrating a real cell proliferation inhibitory activity rather than direct killing effects, were found for some Centaurea, Cirsium, Cichorium, Lactuca, Onopordum and Scorsonera extracts. Copyright © 2009 John Wiley & Sons, Ltd.  相似文献   

14.
As part of our continuing research on seaweeds, crude MeOH extracts of two green, three brown and six red algae collected from Marmara, Black, Aegean and Mediterranean Seas were screened. Four parasitic protozoa, i.e. Plasmodium falciparum, Trypanosoma brucei rhodesiense, T. cruzi, Leishmania donovani and the tubercle bacillus Mycobacterium tuberculosis were used as test organisms for the in vitro assays. The selective toxicity of the extracts was also determined against mammalian L6 cells. All seaweed extracts were active against T. brucei rhodesiense; the Dasya pedicellata extract was the most potent (IC50 value 0.37 µg/mL). The same extract also weakly inhibited the growth of T. cruzi (IC50 62.02 µg/mL). All seaweed extracts also showed leishmanicidal activity (IC50 values 16.76–69.98 µg/mL). The majority of the extracts also exhibited antiplasmodial potential and the most potent extracts were those from D. pedicellata (IC50 0.38 µg/mL), Codium bursa (IC50 1.38 µg/mL) and Caulerpa rasemosa (IC50 3.12 µg/mL). One brown and two red algal extracts showed some weak activity against Mycobacterium tuberculosis (MIC values 125–256 µg/mL). Except for the extract of Dasya pedicellata, none of the extracts displayed any cytotoxicity. This is the second study investigating the antiprotozoal activities of Turkish marine algae and identifies Dasya pedicellata, an understudied algal species, as a candidate for further studies. Copyright © 2010 John Wiley & Sons, Ltd.  相似文献   

15.
The in vitro activity of the methanol extracts of 51 plants randomly collected from the Kingdom of Saudi Arabia and some of their fractions (petroleum ether, chloroform, ethyl acetate and aqueous) were evaluated against Plasmodium falciparum, Trypanosoma brucei brucei, T. cruzi and Leishmania infantum, as well as toxicity against MRC‐5 fibroblast cells. Ten crude methanolic extracts that demonstrated potent and adequately selective antiprotozoal activity were subjected to solvent fractionation using petroleum ether, ethyl acetate and chloroform. Only three samples showed promising antiprotozoal activity. Argemone ochroleuca (CHCl3 fraction) showed pronounced activity against P. falciparumGHA (IC50 0.32 μg/mL) and T. cruzi (IC50 0.30 μg/mL) with low cytotoxicity against MRC‐5 cells (CC50 11.6 μg/mL). Capparis spinosa (EtOAc fraction) showed pronounced activity against P. falciparumGHA with an IC50 0.50 μg/mL in the absence of toxicity against MRC‐5 cell line (CC50 > 30 μg/mL). Heliotropium curassavicum (CHCl3 fraction) showed similar activity against P. falciparum (IC50 0.65 μg/mL; MRC‐5 CC50 > 30 μg /mL). These three extracts will be subjected for further extensive studies to isolate and identify their active constituents. Copyright © 2010 John Wiley & Sons, Ltd.  相似文献   

16.
As part of our continuing research on seaweeds, we have screened the crude extracts of 23 red marine algae collected from England and Ireland. The clinically important blood‐stage life forms of Trypanosoma brucei rhodesiense, T. cruzi, Leishmania donovani and Mycobacterium tuberculosis were used as test organisms in the in vitro assays. The selectivity of the extracts was determined by using mammalian skeletal myoblast (L6) cells. All algal extracts showed activity against T. brucei rhodesiense, with Corallina officinalis and Ceramium virgatum being the most potent (IC50 values 4.8 and 5.4 μg/ml), whilst none of the algal extracts inhibited the growth of T. cruzi. Except for Porphyra leucosticta, extracts from all seaweeds also showed leishmanicidal activity with IC50 values ranging from 16.5 to 85.6 μg/ml. Only the crude extract of Calliblepharis jubata showed some weak activity against Mycobacterium tuberculosis (MIC value 256 μg/ml), while the others were inactive at this concentration. Corallina officinalis was the only seaweed that displayed some marginal cytotoxicity (IC50 value 88.6 μg/ml), and all remaining extracts were non‐toxic towards L6 cells at 90 μg/ml concentration. To our knowledge, this is the first study reporting antiprotozoal and antimycobacterial activity of British and Irish red algae. Copyright © 2010 John Wiley & Sons, Ltd.  相似文献   

17.
In the continuation of our search for natural sources for antiprotozoal and antitubercular molecules, we have screened the crude extracts of four green marine algae (Cladophora rupestris, Codium fragile ssp. tomentosoides, Ulva intestinalis and Ulva lactuca) collected from the Dorset area of England. Trypanosoma brucei rhodesiense, Trypanosoma cruzi, Leishmania donovani and Mycobacterium tuberculosis were used as test organisms in the in vitro assays. The selective toxicity of the extracts was also determined toward mammalian skeletal myoblast (L6) cells. The crude seaweed extracts had no activity against M. tuberculosis, but showed antiprotozoal activity against at least two protozoan species. All algal extracts were active against T. brucei rhodesiense, with C. rupestris being the most potent one (IC50 value 3.7 μg/ml), whilst only C. rupestris and U. lactuca had moderate trypanocidal activity against T. cruzi (IC50 values 80.8 and 34.9 μg/ml). Again, all four extracts showed leishmanicidal activity with IC50 values ranging between 12.0 and 20.2 μg/ml. None of the extracts showed cytotoxicity toward L6 cells, indicating that their antiprotozoal activity is specific. This is the first study reporting antiprotozoal and antimycobacterial activity of British marine algae. Copyright © 2009 John Wiley & Sons, Ltd.  相似文献   

18.
Trypanosomiasis, leishmaniasis, and malaria are protozoan infections of public health importance with thousands of new cases recorded annually. Control of these infection(s) with existing chemotherapy is limited by drug toxicity, lengthy parenteral treatment, affordability, and/or the emergence of resistant strains. Medicinal plants on the other hand are used in the treatment of various infectious diseases although their chemical properties are not fully evaluated. In this study, we screened 112 crude extracts from 72 selected Ghanaian medicinal plants for anti‐Trypanosoma, anti‐Leishmania, and anti‐Plasmodium activities in vitro and investigated their mechanisms of action. Twenty‐three extracts from 20 plants showed significant antiprotozoan activity against at least 1 of 3 protozoan parasites screened with IC50 values less than 20 μg/ml. Eleven extracts showed high anti‐Trypanosoma activity with Bidens pilosa whole plant and Morinda lucida leaf extracts recording the highest activities. Their IC50 (selectivity index [SI]) values were 5.51 μg/ml (35.00) and 5.96 μg/ml (13.09), respectively. Nine extracts had high anti‐Leishmania activity with Annona senegalensis and Cassia alata leaf extracts as the most active. Their IC50 (SI) values were 10.8 μg/ml (1.50) and 10.1 μg/ml (0.37), respectively. Six extracts had high anti‐Plasmodium activity with the leaf and stem‐bark extracts of Terminalia ivorensis recording the highest activity. Their IC50 (SI) values were 7.26 μg/ml (129.36) and 17.45 μg/ml (17.17), respectively. Only M. lucida at 25 μg/ml induced significant apoptosis‐like cell death in Trypanosoma parasites. Anti‐Leishmania active extracts induced varying morphological changes in Leishmania parasites such as multiple nuclei and/or kinetoplast, incomplete flagella division, or nuclear fragmentation. Active extracts may be potential sources for developing new chemotherapy against these infections.  相似文献   

19.
炒青皮的黄酮类成分研究   总被引:10,自引:2,他引:8  
目的 :对青皮的醋炙品进行黄酮类成分研究。方法 :用色谱法和光谱解析法。结果 :分离得到Ⅰ、Ⅱ、Ⅲ、Ⅳ 4个黄酮类化合物 ,分别鉴定为橙皮甙、新橙皮甙、川陈皮素和红橘素。结论 :首次证明生、炒青皮均含有上述4种黄酮类成分。  相似文献   

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