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1.
以草果为原料,通过50%乙醇、水、乙酸乙酯、丙酮、正丁醇、甲醇和石油醚不同极性溶剂萃取活性物质,探讨萃取物中总黄酮和总多酚含量与总还原能力及对DPPH自由基清除率、ABTS+自由基清除率、OH-自由基清除率、NO-2清除能力的相关性。结果表明:50%乙醇萃取物总黄酮和总多酚含量均最高,各萃取物均有抗氧化能力,且呈明显的量效关系,其中50%乙醇萃取物总还原能力、清除ABTS+和DPPH能力最强,石油醚萃取物清除OH-和NO-2能力最强。相关性分析表明,草果萃取物中总黄酮含量与ABTS+清除能力呈极显著相关,与DPPH清除能力呈显著相关,总多酚含量与ABTS+和DPPH的清除能力呈极显著相关,可为草果作为天然抗氧化剂提供理论依据。  相似文献   

2.
The antioxidant activities of the ethanolic extracts of propolis obtained by different extraction methods (high hydrostatic pressure extraction, leaching at room temperature and heat reflux extraction) were investigated in relationship to their total polyphenol and flavonoid contents by two different assays, namely, the β‐carotene bleaching and 1,1‐diphenyl‐2‐picrylhydrazyl (DPPH) free radical scavenging assay systems. The results showed that the ethanolic extracts of propolis obtained by high hydrostatic pressure extraction and leaching at room temperature had relatively strong antioxidant activities, which may be correlated with the total polyphenol and flavonoid contents. Antioxidant activities of ethanolic extracts of propolis obtained by high hydrostatic pressure extraction were the same as those of ethanolic extracts of propolis obtained by leaching at room temperature. Leaching at room temperature usually needs a few days, and can take even more than 7 d, while high hydrostatic pressure extraction needs only 1 min. These findings further illustrate that the high hydrostatic pressure extraction has a bright prospect for extracting flavonoids from propolis.  相似文献   

3.
石菖蒲根茎提取物对粘虫的生物活性   总被引:19,自引:0,他引:19  
谢红英  蒋红云  王国平  冯平章 《农药》2004,43(8):367-369
用石菖蒲的甲醇、石油醚、水等6种不同极性溶剂的提取物对粘虫进行了室内生物活性测定。结果表明:石菖蒲的甲醇提取物对粘虫具有极强的拒食和生长发育抑制作用,兼具一定触杀活性。在非选择性条件下,石菖蒲甲醇提取物对粘虫4龄幼虫拒食率高达91.89%,拒食活性显著高于其它提取物;在毒杀和生长发育抑制试验中,取食含毒叶片后的4龄幼虫体重在3d内出现负增长,4d后试虫全部死亡;此外,石菖蒲甲醇提取物对粘虫幼虫也有一定触杀活性,其死亡率超过60%。在该试验中,石油醚提取物对粘虫幼虫的拒食活性仅次于甲醇提取物,而对粘虫的生长抑制作用则低于甲醇、氯仿及乙酸乙酯3种溶剂的提取物。6种不同极性溶剂提取物中,以水提取物对粘虫的生物活性最小。  相似文献   

4.
The purpose of this study was to evaluate the antioxidant activity (AA) of 19 propolis extracts prepared in different solvent (ethanol and propylene glycol). It was observed that all the samples tested had AA, although results varied considerably between extracts, i.e. 420–1,430 μmol Trolox/g (ABTS), 108–291 mg ascorbic acid/g (DPPH), and 1,573–4,669 μmol iron++ sulfate/g (FRAP). The ethanol may enhance the potency of the AA, and the correlation coefficient between total phenolic content (TPC) (200–340 mg/g propolis extracts) and AA was statistically significant. Total flavonoids ranged from 72 to 161 mg/g propolis extracts. The results indicate that TPC and flavonoids contributed to AA.  相似文献   

5.
The antioxidant activity of different Satureja montana L. subsp. kitaibelii extracts was tested by measuring their ability to scavenge reactive hydroxyl radical during the Fenton reaction, using ESR spectroscopy. Also, the influence of these extracts on lipid peroxyl radicals obtained during lipid peroxidation of: (I) sunflower oil (37 ºC, 3h) induced by 4,4′-azobis(4-cyanovaleric acid) (ACVA) and (II) liposomes induced by 2,2′-azobis(2- amidino-propane)dihydrochloride (AAPH) was studied. n-Butanol extract had the best antioxidant activity (100% at 0.5 mg/mL in Fenton reaction system; 89.21% at 5 mg/mL in system I; 83.38% at 5 mg/mL in system II). The antioxidant activities of the extracts significantly correlated with total phenolic content. The antimicrobial activity of Satureja montana L. subsp. kitaibelii extracts was investigated. Petroleum ether, chloroform and ethyl acetate extracts expressed a wide range of inhibiting activity against both grampositive and gram-negative bacteria.  相似文献   

6.
Antioxidant and antimicrobial activities of Echinacea purpurea L. (Asteraceae) extracts obtained by classical and ultrasound solvent extraction were compared. The dry aerial part of plant was extracted by 70% ethanol at a solid-to-liquid ratio of 1:10 (m/v) and 25°C. The extract obtained by classical solvent extraction contained 29% larger amounts of phenolic compounds and 20% higher content of flavonoids. 2,2-diphenyl-1-picril hydrazyl radical (DPPH) scavenging reached 93.6% and the values of EC50 were (34.16±0.65) μg·ml−1 and (65.48±1.12) μg·ml−1 for the extracts obtained by the classical and ultrasound extractions, respectively. The extracts, independent of the extraction technique applied, showed a considerable growth inhibition on Candida albicans and Saccharomyces cerevisiae, while no growth inhibition zones were observed for Aspergillus niger. The diameters of inhibition zone observed for all the microorganisms were larger for extracts obtained by classical extraction than those by ultrasound extraction.  相似文献   

7.
为评价肿柄菊粗提物毒杀线虫的潜力,利用石油醚、乙酸乙酯、二氟甲烷浸泡粉碎的肿柄菊枝叶混合物,经旋转蒸发获得粗提物,通过浸渍法检测了不同粗提物的毒杀线虫活性。结果表明:当浓度为10mg·mL^-1时,石油醚、乙酸乙酯和二氟甲烷粗提物24~72h内对线虫的毒杀效果较弱;当浓度为20mg·mL^-1时,二氯甲烷粗提物毒杀线虫活性最好,处理72h的线虫校正死亡率可达50.6%,乙酸乙酯粗提物和石油醚粗提物毒杀线虫活性均较弱;当浓度为40mg·mL^-1时,毒杀线虫活性大小依次是乙酸乙酯粗提物〉石油醚粗提物〉二氯甲烷粗提物,其中乙酸乙酯粗提物处理72h的线虫校正死亡率达73.6%。表明,对肿柄菊粗提物进行合理的处理、分离、纯化,有望开发出高效低毒、绿色环保的新型杀线虫农药。  相似文献   

8.
以向日葵茎髓为原料,制得3种不同极性向日葵茎髓提取物。采用琼脂扩散法测定3种不同极性向日葵茎髓提取物对4种受试菌的抑菌活性;并以其中的金黄色葡萄球菌和大肠杆菌为研究对象,探讨了乙酸乙酯萃取部位(EE)的抑菌机制。结果显示:不同极性萃取部位对4种受试菌均有一定抑制作用。其中,EE处理金黄色葡萄球菌和大肠杆菌的最低抑菌质量浓度(MIC)均为0.78 g/L,半数抑制质量浓度(IC50)分别为(1.11?0.01)和(1.59?0.03)g/L;抑菌作用与其总酚、总黄酮含量呈显著正相关性(P0.05)。通过SEM分析发现,EE处理引起菌体形态变化,破坏菌体的细胞膜结构;EE可增加金黄色葡萄球菌和大肠杆菌细胞膜结构的通透性,使菌体内的电解质、蛋白质、碱性磷酸酶向胞外泄露;应用4?,6-二脒基-2-苯基吲哚(DAPI)染色和荧光检测发现,EE能干扰细菌遗传物质(DNA)的复制,最终抑制受试菌增殖。  相似文献   

9.
This study focused on the biological evaluation and chemical characterization of Geranium pyrenaicum Burm. f. Different solvent extracts (hexane, ethyl acetate, methanol, and water extracts) were prepared. The phytochemical profile, antioxidant, and enzyme inhibitory activity were investigated. Cytotoxicity was assessed using VERO, FaDu, HeLa and RKO cells. The antiviral activity was carried out against HSV-1 (Herpes simplex virus 1) propagated in VERO cell line. The aqueous extract, possessing high phenolic content (170.50 mg gallic acid equivalent/g extract), showed the highest reducing capacity (613.27 and 364.10 mg Trolox equivalent/g extract, for cupric reducing antioxidant capacity and ferric reducing antioxidant power, respectively), radical scavenging potential (469.82 mg Trolox equivalent/g extract, against 2,2′-azino-bis(3-ethylbenzothiazoline-6-sulfonic acid)), metal chelating ability (52.39 mg ethylenediaminetetraacetic acid equivalent/g extract) and total antioxidant capacity (3.15 mmol Trolox equivalent/g extract). Liquid chromatography-electrospray ionization-quadrupole time-of-flight-mass spectrometry (LC-ESI-QTOF-MS/MS) alloved to tentatively identify a total of 56 compounds in the extracts, including ellagitannins, gallic acid and galloyl derivatives amongst others. The ethyl acetate extracts substantially depressed cholinesterase enzymes (4.49 and 12.26 mg galantamine equivalent/g extract against AChE and BChE, respectively) and α-amylase enzyme (1.04 mmol acarbose equivalent/g extract). On the other hand, the methanolic extract inhibited tyrosinase (121.42 mg kojic acid equivalent/g extract) and α-glucosidase (2.39 mmol acarbose equivalent/g extract) activities. The highest selectivity towards all cancer cell lines (SI 4.5–10.8) was observed with aqueous extract with the FaDu cells being the most sensitive (CC50 40.22 µg/mL). It can be concluded that the presence of certain bioactive antiviral molecules may be related to the high anti HSV-1 activity of the methanolic extract. This work has generated vital scientific data on this medicinal plant, which is a prospective candidate for the creation of innovative phyto-pharmaceuticals.  相似文献   

10.
段志芳  李充璧 《化学世界》2012,53(3):172-175
超声波最优化法提取溪黄草总黄酮,提取物经乙酸乙酯萃取后进行柱层析分离纯化,得一纯物质,鉴定为黄酮化合物,并以该化合物为配体合成了锌(Ⅱ)、铜(Ⅱ)和铁(Ⅲ)配合物,研究它们对亚硝化反应的抑制作用。结果表明该黄酮化合物及其配合物在一定浓度范围能阻断亚硝胺的合成及清除亚硝酸盐,其中配合物作用较黄酮配体强。  相似文献   

11.
为研究测定麦秆中分离的不同提取成分对小鼠腹水瘤S180细胞增殖的抑制效果,以干燥麦秆为原料,水、乙醇、正丁醇、乙酸乙酯和正己烷等为提取剂,透析、活性炭吸附和重结晶方法初步分离,硅胶柱层析进一步分离,得到数种麦秆提取成分,并用MTT〔3-(4,5-二甲基噻唑-2)-2,5-二苯基四氮唑溴盐〕法测定了其对小鼠S180细胞生长的抑制作用;用显微摄像观察了对S180细胞的抑制作用,血细胞计数法测定了对正常脾细胞的毒性作用。结果表明,用正己烷提取得到的粗提物E对S180细胞抑制作用较强,E初步分离得到的分离组分F2抑制作用较好,F2硅胶柱层析得到分离组分I抑制效果最好,I在5~160 mg/L范围内对S180细胞的增殖均有抑制作用,呈现出良好的剂量-效应关系,IC50为68.0 mg/L;I对体外培养的正常脾细胞有轻微毒性,在68.0 mg/L质量浓度下处理48 h后的抑制率为9.3%。  相似文献   

12.
飞龙掌血提取物抑菌作用初步研究   总被引:2,自引:0,他引:2  
选择蒸馏水、无水乙醇、乙酸乙酯、石油醚4种提取剂,采用冷浸、加热回流两种方法萃取飞龙掌血,比较提取物对枯草杆菌、痢疾杆菌、啤酒酵母菌的抑菌效果。结果表明,冷浸 72 h 和加热回流 5 h 的飞龙掌血提取物对该3种菌的抑菌作用无显著差异,无水乙醇、乙酸乙酯提取物较水提物有显著差异;生药质量浓度为 0.25 g/mL 的乙醇提取物对3种菌都有极显著的抑菌效果,适宜抑菌生药质量浓度为 0.5 g/mL;pH值对该提取物的抑菌效果影响较大,3个菌种适宜抑菌的pH值不同。  相似文献   

13.
The objectives of this study were to isolate various isoflavone fractions and extracts from soybean cake by preparative column chromatography and compare them with isoflavone standards with regards to inhibition of HepG2 cancer cell proliferation. Four fractions, including malonylglucoside, glucoside, acetylglucoside and aglycone, and two isoflavone extracts, ISO-1 and ISO-2, were collected for evaluation. MTT test results showed that most treatments were slightly protective against HepG2 cell growth at a low dose of isoflavone (5 and 10 μg/mL). However, at elevated concentration of isoflavone (20–50 μg/mL), both aglycone and acetylglucoside fractions as well as a mixture of isoflavone standards were the most effective in inhibition, demonstrating a possible synergistic phenomenon. Genistein showed a better retardation effect than daidzein. For cell cycle analysis, both aglycone and acetylglucoside fractions and a mixture of isoflavone standards exhibited a high G2/M ratio, correlating well with the result of MTT test. The presence of some other functional components in soybean cake like saponins and phenolic compounds may also play a vital role in inhibiting HepG2 cell growth.  相似文献   

14.
海南核果木抗氧化活性研究   总被引:3,自引:3,他引:0  
陈德力  肖曼  刘平怀 《精细化工》2011,28(11):1103-1106
将海南核果木干燥枝叶用乙醇浸提,对总提物分别用石油醚、乙酸乙酯、正丁醇萃取,并以DPPH法和FRAP法对总提物及各萃取物的抗氧化活性进行评价。结果显示,在DPPH法中海南核果木总提物(DH)、石油醚萃取物(DHMSO)、乙酸乙酯萃取物(DHEtOAC)、正丁醇萃取物(DHNBA)、水相(DHH2O)的IC50分别为77.3、115.2、51.4、342.9、205.7 mg/L,其FRAP值分别为(11 712.2±931.8)、(10 820.9±690.5)、(14 386.4±568.8)、(1 157.6±63.3)、(5 584.1±182.3)μmol Fe2+/g。且抗坏血酸(Vc)和BHT的IC50分别为10.7、47.1mg/L,FRAP值分别为(18 022.8±63.3)、(14 568.7±137.0)μmol Fe2+/g,并通过多元聚类分析表明DH、DHMSO、DHEtOAC与BHT、Vc具有类似强度的抗氧化活性,可归为同一类型,且DHEtOAC抗氧化活性与BHT无显著性差异,说明其粗提物具有较强的抗氧化活性。  相似文献   

15.
The feeding deterrent properties of hexane, ethyl acetate, and butanol lipophilic extracts of 16 species of Bermudian sponges presented to the sergeant major,Abudefduf saxatilus, and the Bermuda bream,Diplodus bermudensis, were investigated in the laboratory. The sponges investigated spanned a variety of different color morphs and were representative of patch reef, mangrove, rock wall, soft bottom, seagrass, and cave habitats. Six of the 16 sponges (36%) had at least one extract that deterred feeding byA. saxatilus, while only one of 16 sponges (6%) had an extract that deterred feeding byD. bermudensis. Among those sponges that deterred feeding in one or both fish, deterrence was most frequently associated with compounds extracted in ethyl acetate (moderately polar). Butanol extracts (most polar) were active in only half as many instances, while in only one case was a hexane extract (least polar) active. Both brighly colored (yellow, orange–yellow, gray–blue, purple–brown) and weakly colored (dull brown, pinkish white) sponges had hexane, ethyl acetate, or butanol extracts that were deterrent. Generally the numbers of sponges with bioactive lipophilic extracts that caused feeding deterrence in fish was low. This may be related to Bermuda being located just within or beyond the extreme northern range of many tropical fish and invertebrates, and therefore sponges are exposed to reduced levels of predation.  相似文献   

16.
通过正交试验探讨了巨尾桉叶中原花色素的3种提取方法的最佳提取工艺条件,并进行了对比。结果显示,传统溶剂提取法的最优工艺为:60%乙醇、80 ℃、100 min、料液比1:14(g:mL,下同),原花色素得率5.95%;微波辅助提取法的最优工艺为:50%乙醇、微波功率200 W、微波时间4 min、料液比为1:20,得率5.48%;超声波辅助提取法的最优工艺为:60%乙醇、60 ℃、超声波时间25 min、料液比为1:14,得率为6.07%。超声波辅助提取法效果最好,时间短,得率高。实验对超声波提取物的不同溶剂萃取物体外抗氧化性和抗肿瘤活性进行了研究,结果表明,乙酸乙酯萃取物抗氧化作用较强,当质量浓度为1.2 g/L时,对DPPH自由基清除率达到96.33%;乙酸乙酯萃取物质量浓度为2 g/L时,对于人肝癌细胞Bel-7404具有很强的抗肿瘤活性,抑制率为56.37%。  相似文献   

17.
海滩植物厚藤(Ipomoea Pes-caprae)抗氧化活性研究   总被引:1,自引:0,他引:1  
采用加速溶剂萃取技术(ASE)快速制备厚藤活性提取物,并以DPPH法对厚藤茎叶不同溶剂提取物抗氧化活性进行评价。抗坏血酸抗氧化能力乙酸乙酯提取物抗氧化能力乙醇提取物抗氧化能力甲醇提取物抗氧化能力石油醚提取物抗氧化能力,其IC50值分别为0.203 4、0.836 2、0.868 8、1.867 5、6.628 3 g/L。结果显示,厚藤茎叶提取物具有一定的抗氧化活性,且以乙酸乙酯为提取溶剂时,效果最佳。  相似文献   

18.
The focus of the present research was to study inhibition of lipoxygenase activity by rapeseed native polyphenols and the interactions between those compounds and the enzyme. The enzyme and polyphenolic compounds (polyphenols, phenolic acids) were extracted from rapeseed (Brassica napus) varieties Aviso and PR45DO3. The total phenolic compounds concentration in tested rapeseed was 1,485–1,691 mg/100 g d.m. (dry matter) and the free phenolic acids content in both rapeseed varieties was about 76 μg/100 g d.m. The isolated proteins showed lipoxygenase activity. Prooxidant properties of phenolic compounds in the presence of lipoxygenase and linoleic acid were observed rather in the case of extracts containing a relatively high concentration of miscellaneous polyphenols. Antioxidant properties were recorded in the case of phenolic acid extracts which contain only 1.4–1.9% of phenolics present in raw phenolic extracts. We propose that the prooxidant effect of phenolic compounds comes from quinone and oxidized polyphenols formation. The observed antioxidant activity of phenolic acid extracts is probably due to their ability to scavenge free radicals formed from linoleic acid. However, reduction of lipoxygenase ferric to ferrous ions, which prevent the activation of the enzyme and inhibited its activity, was also observed.  相似文献   

19.
将混合发酵技术用于南海红树内生真菌E33和K38的培养,发酵液乙酸乙酯和正丁醇萃取物对多种植物病原菌显示强烈抑制作用,抑制率比单独发酵平均增加1~3倍。LC-MS检测显示混合发酵时代谢物种类显著增加,表明两菌发展出不同于单独发酵的代谢途径,产生了强效抗菌活性物质。  相似文献   

20.
Different extraction processes were employed to extract the polyphenolic compounds from pitanga (Eugenia uniflora L.) leaves: a one-step process using water, ethanol or supercritical CO2 as solvents, and a two-step process using supercritical CO2 followed by either water or ethanol. The total polyphenolic compounds, total flavonoids and antioxidant activity were determined in all the extracts obtained. The process performance was evaluated with respect to three variables: global extraction yield, concentration and yield of both polyphenols and flavonoids in the extracts. For the one-step extraction, the results showed that the extraction yield increased with solvent polarity. For the two-step process, the results suggested that water was more efficient in extracting the phenolic compounds from E. uniflora when the matrix was previously extracted with scCO2. With respect to the antioxidant activity, the ethanolic extracts obtained from both processes, using either the DPPH radical scavenging method or the β-carotene bleaching method, presented high antioxidant activities.  相似文献   

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