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Study on the Free Radical Scavenging Activity of Sea Cucumber (Paracaudina chinens var.) Gelatin Hydrolysate 被引量:1
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作者 ZENG Mingyong XIAO Feng ZHAO Yuanhui LIU Zunying LI Bafang DONG Shiyuan 《Journal of Ocean University of China》 SCIE CAS 2007年第3期255-258,共4页
Gelatin from the sea cucumber(Paracaudina chinens var.) was hydrolyzed by bromelain and the hydrolysate was found to have a high free radical scavenging activity. The hydrolysate was fractionated through an ultrafiltr... Gelatin from the sea cucumber(Paracaudina chinens var.) was hydrolyzed by bromelain and the hydrolysate was found to have a high free radical scavenging activity. The hydrolysate was fractionated through an ultrafiltration membrane with 5 kDa molecular weight cutoff(MWCO). The portion(less than 5 kDa) was further separated by Sephadex G-25. The active peak was col-lected and assayed for free radical scavenging activity. The scavenging rates for superoxide anion radicals(O2·-) and hydroxyl radi-cals(·OH) of the fraction with the highest activity were 29.02% and 75.41%,respectively. A rabbit liver mitochondrial free radical damage model was adopted to study the free radical scavenging activity of the fraction. The results showed that the sea cucumber gelatin hydrolysate can prevent the damage of rabbit liver and mitochondria. 展开更多
关键词 Paracaudina chinens var. gelatin hydrolysate free radical scavenging activity MITOCHONDRIA
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STUDIES ON FREE RADICAL SCAVENGING ACTIVITY IN CHINESE SEAWEEDS PART I. SCREENING RESULTS 被引量:4
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作者 严小军 房国明 娄清香 《Chinese Journal of Oceanology and Limnology》 SCIE CAS CSCD 1999年第3期240-246,共7页
Antioxidants have attracted the attention of researchers due to their beneficial effects as free radical scavengers. Application of a stable free radical named 1,1 diphenyl 2 picrylhydrazyl(DPPH) to screen the free ra... Antioxidants have attracted the attention of researchers due to their beneficial effects as free radical scavengers. Application of a stable free radical named 1,1 diphenyl 2 picrylhydrazyl(DPPH) to screen the free radical scavenging activity in 27 species of Chinese seaweed showed that 15 of them had significant activity in at least one of the organic solvent extracts. The most interesting seaweed species were Gelidium amansii, Gloiosiphonia capillaris, Polysiphonia urceolata, Sargassum kjellmanianum, Desmarestia viridis, and Rhodomela teres. 展开更多
关键词 SEAWEED antioxidant free radical DPPH scavenging activity
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Evaluation of free radical scavenging activity of various extracts of leaves from Kedrostis foetidissima(Jacq.)Cogn 被引量:7
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作者 Kalaisezhiyen Pavithra Sasikumar Vadivukkarasi 《Food Science and Human Wellness》 SCIE 2015年第1期42-46,共5页
The present study was aimed to investigate the in vitro free radical scavenging activity of various leaf extracts(aqueous,methanol,acetone chloroform and petroleum ether)of Kedrostis foetidissima.In vitro free radical... The present study was aimed to investigate the in vitro free radical scavenging activity of various leaf extracts(aqueous,methanol,acetone chloroform and petroleum ether)of Kedrostis foetidissima.In vitro free radical scavenging activities of the extracts were assessed against DPPH and hydroxyl radicals.The metal chelating activity and reducing power ability of the extracts were also determined.The free radical scavenging activity was found to be high in methanolic extract for DPPH and hydroxyl radicals in a concentration dependent manner followed by chloroform,aqueous,acetone and petroleum ether extracts.The metal chelating activity and reducing power ability was also found to be high in methanolic extract.The difference in scavenging potential of the extracts may be due to variation in the percentage of phytoconstituents extracted in various solvents.Thus the result suggests that the methanolic leaf extract of K.foetidissima could serve as a potential source of antioxidants and can be explored as a therapeutic agent in free radical induced diseases.©2015 Beijing Academy of Food Sciences.Production and hosting by Elsevier B.V.All rights reserved. 展开更多
关键词 free radicals Kedrostis foetidissima ANTIOXIDANTS PHENOLS scavenging activity
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Evaluation of the Antimicrobial and Anti-Free Radical Scavenging Properties and Phytochemical Analysis of Hydroethanolic Extract of Phyllanthus muellerianus (Kuntze) Exell
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作者 Fo-Doh Clefasse Koula Yao Hoekou +8 位作者 Koffi Mawufemo Bledu Tibanguebé Doumongue Yao Hoinsou Luckman Gbati Efui Holaly Gbekley Kossi Mawuéna Novidzro Koffi A. Gbogbo Tchadjobo Tchacondo Yaovi A. Ameyapoh 《Journal of Biosciences and Medicines》 2024年第12期79-95,共17页
The aim of this study was to evaluate the antimicrobial and antiradical properties of extracts from the leaves, stems and roots of Phyllanthus muellerianus, a plant used in traditional Togolese medicine. Agar well-dif... The aim of this study was to evaluate the antimicrobial and antiradical properties of extracts from the leaves, stems and roots of Phyllanthus muellerianus, a plant used in traditional Togolese medicine. Agar well-diffusion and broth microdilution methods were used to assess the antimicrobial potential of hydroethanolic extracts from plant organs. Phytochemical compounds, total phenol and condensed tannin content, and free radical scavenging activity were determined in the three extracts. The results of the antimicrobial tests showed that the extract of P. muellerianus leaves was the most active on Staphylococcus strains, with inhibition diameters of 17 to 23 mm and minimum inhibitory concentrations (MICs) of between 2.5 and 10 mg/mL. Tannins, saponins, alkaloids and flavonoids were found in all extracts. The P. muellerianus leaf extract has 4.23 ± 0.25 mgAGE/g of total phenols, the stem extract has 2.96 ± 0.05 mgCE/g of condensed tannins and the root extract expressed a higher antiradical compounds content (0.125 ± 0.003 mgAAE/g). The results of this study demonstrate the antimicrobial and free radical scavenging potential of the plant and contribute to justify its use in traditional medicine. 展开更多
关键词 Phyllanthus muellerianus Hydroethanolic Extract Antimicrobial activity Phytochemical Compounds free radical scavenging Power
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Component Analysis and Free Radicals Scavenging Activity of Physalis alkekengi L. Polysaccharide 被引量:20
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作者 CHENG Ying-kun LI Lei MENG Zhao-kun HOU A-li WU Yu-jie TENG Li-rong 《Chemical Research in Chinese Universities》 SCIE CAS CSCD 2008年第2期167-170,共4页
A crude polysaccharide was extracted from Physalis alkekengi L. fruit. HPLC was used for the component analysis of the polysaccharide. The results indicate that Physalis alkekengi L. polysaccharide(PAP) was composed... A crude polysaccharide was extracted from Physalis alkekengi L. fruit. HPLC was used for the component analysis of the polysaccharide. The results indicate that Physalis alkekengi L. polysaccharide(PAP) was composed of rhamnose, xylose, arabinose, galactose, and glucose. Free radicals scavenging activity of PAP was studied through 3 free radicals scavenging tests. PAP exhibited high scavenging effects on OH and DPPH radicals, and both the scavenging rates were about 80%. The scavenging rate of O2^- radical was about 22%. 展开更多
关键词 PHYSALIS POLYSACCHARIDE Component analysis free radicals scavenging activity
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Constituents from Aerial Parts of Bidens ceruna L. and Their DPPH Radical Scavenging Activity 被引量:2
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作者 ZHU Na LI Xu-wen LIU Gui-ying SHI Xiao-lei GUI Ming-yu SUN Chang-qing JIN Yong-ri 《Chemical Research in Chinese Universities》 SCIE CAS CSCD 2009年第3期328-331,共4页
A new chalcone glycoside, butein-4-methoxyl-4′-O-(6"-O-acetyl)-β-D-glucopyranoside(2), along with seven known compounds, namely, quercitrin(1), luteolin-7-O-β-D-glucopyranoside(3), butein-4'-O-β-D-glucop... A new chalcone glycoside, butein-4-methoxyl-4′-O-(6"-O-acetyl)-β-D-glucopyranoside(2), along with seven known compounds, namely, quercitrin(1), luteolin-7-O-β-D-glucopyranoside(3), butein-4'-O-β-D-glucopyranoside(4), butein-4-methoxyl-4'-O-β-D-glucopyranoside(5), butin-7-O-β-D-glucopyranoside(6), isoquercitrin(7), and sulfurein(8) was isolated from aerial parts of Bidens ceruna L. Their structures were elucidated on the basis of spectroscopic studies. Compounds 1-8 were tested for their DPPH radical scavenging activity and, except compounds 2 and 5, other compounds showed scavenging activitv. 展开更多
关键词 Bidens ceruna L. constituent Flavonoid DPPH radical scavenging activity
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Sonme Factors that Affect the Free Radical-scavenging Activity of Tea Extracts 被引量:9
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作者 Zhao Xinhuai ( Northeast Agricultural University, Harbin 150030 PRC) 《Journal of Northeast Agricultural University(English Edition)》 CAS 1999年第1期62-67,共6页
Some factors that affect the free radical-scavenging activety of two tea extracts were studied in vitro. It was found that concentration of tea extract or heating tea extract or treating with activated carbon and di... Some factors that affect the free radical-scavenging activety of two tea extracts were studied in vitro. It was found that concentration of tea extract or heating tea extract or treating with activated carbon and diatomite all had obvious effect on the scavenging activety of green tea extract ,but heating or treating with diaomite had less effect on the scavenging activity of black tea extract. Ascorbic acid, for having synergic effect with tea extracts, could enhance the scavenging activity of tea extracts markedly, and the contrary was cupric ion. Reducing sugars such as fructose and glucose also had some syncrgic effect to tea extracts. 展开更多
关键词 Tea extract. hydroxyl radical. free radival-scavenging activity
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Free Radical-Scavenging Properties and Antioxidant Activity of Fractions from Cranberry Products
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作者 Stéphane Caillet Guillaume Lorenzo +2 位作者 Jacinthe Coté Jean-Francois Sylvain Monique Lacroix 《Food and Nutrition Sciences》 2012年第3期337-347,共11页
Lipid peroxidation inhibition capacity and antiradical activity were evaluated in HPLC fractions of different polarity obtained from two cranberry juices and three extracts isolated from frozen cranberries and pomace ... Lipid peroxidation inhibition capacity and antiradical activity were evaluated in HPLC fractions of different polarity obtained from two cranberry juices and three extracts isolated from frozen cranberries and pomace containing antho-cyanins, water-soluble and apolar phenolic compounds, respectively. Compounds with close polarities were collected to obtain between three and four fractions from each juice or extract. The cranberry phenols are good free radi-cal-scavengers, but they were less efficient at inhibiting the lipid peroxidation. Of all the samples tested, the intermediate polarity fraction of extract rich in apolar phenolic compounds of fruit presented the highest antiradical activity while the most hydrophobic fractions of the anthocyanin-rich extract from fruit and pomace appeared to be the most efficient at inhibiting the lipid peroxidation. The antioxidant or pro-oxidant activity of fractions increased with the con-centration. The phenol polarity and the technological process to manufacture cranberry juice can influence the antioxidant and antiradical activities of fractions. 展开更多
关键词 HPLC Fractions Cranberry Juices Phenolic Extracts free radical scavenging Capacity Antioxidant activity
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Antioxidant Activity of Anthocyanins Extracted from Iraqi <i>Iresine herbstii</i>L. Flowers after Drying and Freezing 被引量:2
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作者 Adnan J. M. Al-Fartosy Ali Abdulrazzaq Abdulwahid 《American Journal of Analytical Chemistry》 2015年第5期382-394,共13页
Any processing method that maintains the level of compounds known for their health benefits will be of interest to the food industries. Therefore, the effects of vacuum drying, storage and freezing on the anthocyanin ... Any processing method that maintains the level of compounds known for their health benefits will be of interest to the food industries. Therefore, the effects of vacuum drying, storage and freezing on the anthocyanin content and their antioxidant properties of Iresine herbstii L. flowers were investigated. The results showed that fresh samples (AEFF) had the highest amount of total anthosyanin content (8.31 ± 0.23 mg/g dry matter, expressed as cyaniding 3-glucoside equivalents), followed by 7.17 ± 0.12 mg/g solid content, 13.72% loss of vacuum dried samples (AEDF). In comparison with fresh samples, total anthocyanins in stored samples for two weeks at 5°C (AESF) and frozen samples during 1 (AEZF1) and 3 months (AEZF3) of storage were significantly (P < 0.01) reduced to 6.43 ± 0.24 mg/g solid content, 22.63% loss, 5.65 ± 0.33 mg/g solid content, 32.01% loss and 4.71 ± 0.51 mg/g solid content, 43.33% loss, respectively. Anthocyanins from I. herbstii L. flowers exhibited a dose-dependent (AEFF > AEDF > AESF > AEZF1 > AEZF3, respectively) antioxidant activity against lipid peroxidation in a linoleic acid model system as well as strong reducing power and ferrous ion chelating abilities. Moreover, the anthocyanins extracted were found to show remarkable scavenging activity on superoxide anion radicals, hydroxyl radicals, hydrogen peroxide, nitric oxide radicals and deoxyribose degradation. Based on the results obtained, we can concluded that the Iresine herbstii L. flowers may be valuable natural antioxidant sources and are potentially applicable in both pharmacy and food 展开更多
关键词 Iresine herbstii L. FLOWERS Anthocyanin Frozen Storage Vacuum DRYING Total Antioxidant activity free radical scavenging activity
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古红橘皮精油挥发性成分分析及清除自由基活性成分筛选
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作者 冉春霞 胡江 邓惠玲 《食品与机械》 北大核心 2025年第2期136-144,共9页
[目的]分析古红橘新鲜橘皮精油的挥发性成分,评价其总体自由基清除活性,在不分离单体的情况下快速筛选其中自由基清除活性较强的成分。[方法]以古红橘新鲜橘皮为原料,分别采用共水蒸馏法和水蒸气蒸馏提取橘皮精油,分析不同方法提取精油... [目的]分析古红橘新鲜橘皮精油的挥发性成分,评价其总体自由基清除活性,在不分离单体的情况下快速筛选其中自由基清除活性较强的成分。[方法]以古红橘新鲜橘皮为原料,分别采用共水蒸馏法和水蒸气蒸馏提取橘皮精油,分析不同方法提取精油的挥发性成分,筛选特征挥发性差异成分,并采用GC-MS和化学方法筛选自由基清除活性成分。[结果]2种提取方法所得精油的挥发性成分的种类、相对含量、特征挥发性成分及总体自由基清除活性差异极显著(P<0.001),共水蒸馏为最优的古红橘皮精油提取方法;各挥发性成分的自由基清除活性存在较大差异,柠檬醛(86.54%)、甜橙醛(81.20%)、α-法尼烯(70.29%)等表现出很强的DPPH自由基清除活性,而橙花醇(95.02%)、甜橙醛(83.09%)表现出极强的ABTS^(+)自由基清除活性。[结论]古红橘新鲜橘皮提取的精油的挥发性成分和自由基清除活性受到提取方法的影响,各挥发性成分的相对含量与其自由基清除活性之间没有直接的相关性。 展开更多
关键词 古红橘 新鲜橘皮 精油 GC-MS 挥发性成分 自由基清除活性成分 筛选
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不同刈割时期黑沙蒿水提物体外抗氧化活性的研究
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作者 姜联广 赵艳丽 +3 位作者 闫晶 闫素梅 郭晓宇 郭咏梅 《饲料研究》 北大核心 2025年第3期85-89,共5页
试验旨在研究不同刈割时期黑沙蒿水提物(AOE)主要生物活性成分及体外抗氧化活性。采用单因素完全随机试验设计,分别于7、8、9和10月刈割将黑沙蒿后,制备AOE,测定不同刈割时期AOE的多糖、总酚和总黄酮含量及其对铁离子的还原力、羟基自... 试验旨在研究不同刈割时期黑沙蒿水提物(AOE)主要生物活性成分及体外抗氧化活性。采用单因素完全随机试验设计,分别于7、8、9和10月刈割将黑沙蒿后,制备AOE,测定不同刈割时期AOE的多糖、总酚和总黄酮含量及其对铁离子的还原力、羟基自由基清除率和1,1-二苯基-2-三硝基苯肼(DPPH)自由基的清除率。结果表明,不同月份刈割制备的AOE的体外抗氧化活性随着稀释液浓度的增加而上升,后趋于平缓。与8、9、10月相比,7月刈割制备的AOE的总酚量和总黄酮含量最高,体外抗氧化活性最强;与7、9、10月相比,8月刈割制备的AOE的多糖含量最高,体外抗氧化活性低于7月。AOE的综合评价抗氧化能力(APC)指数与总酚含量呈极显著正相关(P<0.01),与总黄酮含量呈显著正相关(P<0.05)。研究表明,黑沙蒿可作为潜在的天然抗氧化剂资源,不同刈割时期的生物活性成分和体外抗氧化活性存在一定的差异,7月刈割的黑沙蒿制备水提物效果较好。 展开更多
关键词 黑沙蒿水提物 抗氧化活性 刈割时期 自由基清除率
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不同提取方法对番石榴叶有效成分、抗氧化及α-糖苷酶抑制活性的影响
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作者 罗朝丹 王秋菊 +5 位作者 李建强 冯春梅 任二芳 黄燕婷 宁琳 罗小杰 《热带作物学报》 北大核心 2025年第3期705-715,共11页
为了联合评价浸渍法、热回流法、超声辅助乙醇和超声辅助低共溶试剂法(UADEE)对番石榴叶的提取效果,通过扫描电镜观察番石榴叶样品的显微结构,以香草醛-冰醋酸比色法、NaNO_(2)-Al(NO_(3))3比色法、福林酚法分别测定番石榴叶提取液的总... 为了联合评价浸渍法、热回流法、超声辅助乙醇和超声辅助低共溶试剂法(UADEE)对番石榴叶的提取效果,通过扫描电镜观察番石榴叶样品的显微结构,以香草醛-冰醋酸比色法、NaNO_(2)-Al(NO_(3))3比色法、福林酚法分别测定番石榴叶提取液的总皂苷、总黄酮、总酚含量,采用HPLC法测定番石榴叶中黄酮单体的含量,LC-MS法分析其代谢物,并评估其抗氧化与α-糖苷酶抑制活性。结果表明:UADEE对番石榴叶细胞内部结构的破坏性最强,样品总皂苷、总黄酮与总酚含量分别为79.28、80.51、120.52mg/g,黄酮成分番石榴苷、萹蓄苷、瑞诺苷含量分别为7.96、7.74、3.99mg/g,显著高于其他3组(P<0.05);UADEE处理组中黄酮类、三萜类、酚类成分在番石榴叶总代谢物中分别占9.830%、27.267%、1.013%。UADEE组样品清除DPPH自由基的IC_(50)值和抑制α-葡萄糖苷酶的IC_(50)值分别为45.18、904.67μg/mL,活性显著强于其他3组(P<0.05)。本研究结果为番石榴叶有效成分的高效提取及其加工产品的开发提供实验依据。 展开更多
关键词 番石榴叶 超声辅助低共熔溶剂法 有效成分 DPPH自由基清除率 α-糖苷酶抑制活性
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大球盖菇多肽的制备、抗氧化及抗肿瘤活性的研究
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作者 杨敏 张密 +4 位作者 叶贤胜 曾长立 马爱民 牛蒙亮 许丹云 《山西农业大学学报(自然科学版)》 北大核心 2025年第1期123-132,共10页
[目的]大球盖菇作为近年来在我国迅速崛起的食用菌,以其卓越的营养价值和多样的保健功效受到市场的青睐。然而,尽管其产量迅猛增长,深度加工技术的滞后和创新产品开发的不足已成为制约大球盖菇产业发展的关键因素。因此,本研究旨在优化... [目的]大球盖菇作为近年来在我国迅速崛起的食用菌,以其卓越的营养价值和多样的保健功效受到市场的青睐。然而,尽管其产量迅猛增长,深度加工技术的滞后和创新产品开发的不足已成为制约大球盖菇产业发展的关键因素。因此,本研究旨在优化大球盖菇多肽的制备工艺,并评价其体外抗氧化和抗肿瘤活性,为大球盖菇的深度加工和产品创新提供科学依据。[方法]以蛋白水解度为评价指标,在蛋白酶筛选的基础上,通过单因素和正交试验获得大球盖菇多肽的最佳制备工艺,并通过超滤分级纯化获得3个多肽组分(M1:>10 kDa、M2:3~10 kDa、M3:<3 kDa);通过DPPH·和ABTS^(+)·清除率的测定评价多肽体外抗氧化活性。通过常见肿瘤细胞增殖抑制率的测定评价多肽抗肿瘤活性。[结果]胰蛋白酶酶解制备大球盖菇多肽的最佳工艺为料液比1∶20 g/mL、酶添加量4000 U/g、酶解时间3 h,在该条件下大球盖菇蛋白的水解度为28.31%,比优化前提高了3倍。所制备的大球盖菇多肽对DPPH·和ABTS^(+)·的清除率最高可达69.2%和91.4%,高于以往相关报道。3个多肽组分对4种常见的肿瘤细胞(宫颈癌细胞HeLa、肺癌细胞NCI-H460、乳腺癌细胞BT549、肝癌细胞HepG2)的抑制效果不同,但均呈现浓度依赖性。M1和M3对肺癌细胞NCI-H460的抑制效果最好,而M2主要抑制宫颈癌细胞HeLa;其中,500μg/mL M3对肺癌细胞NCI-H460的抑制率达30.28%。[结论]胰蛋白酶酶解制备大球盖菇多肽的工艺优化后,所制备的多肽具有良好的抗氧化活性和抗肿瘤活性。 展开更多
关键词 大球盖菇 多肽 酶解 自由基清除率 抗肿瘤活性
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桦木汁对斑马鱼胚胎的体外抗氧化作用及体内酶学检测
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作者 邢琦 陈海燕 +3 位作者 华李羽 王超 李轲 刘纪盈 《食品与机械》 北大核心 2025年第2期160-165,共6页
[目的]研究长白山天然桦木汁的抗氧化活性。[方法]通过DPPH自由基清除率、ABTS阳离子自由基清除率、羟自由基清除率、铁离子还原能力(FRAP)4种化学法测定其抗氧化活性水平,并利用模式生物—斑马鱼胚胎检测其动态酶学指标。[结果]桦木汁... [目的]研究长白山天然桦木汁的抗氧化活性。[方法]通过DPPH自由基清除率、ABTS阳离子自由基清除率、羟自由基清除率、铁离子还原能力(FRAP)4种化学法测定其抗氧化活性水平,并利用模式生物—斑马鱼胚胎检测其动态酶学指标。[结果]桦木汁的抗氧化效果随汁液浓度的增加呈正相关,氧化活性因子显著。当桦木汁用量为1.0 mL/mL时,其抗氧化效果最佳,且对DPPH自由基清除率、ABTS阳离子自由基清除率、羟自由基清除率、铁离子还原能力分别为34.56%,18.27%,48.77%,90.07μmol/L,斑马鱼胚胎SOD、CAT、GSH-Px活性以及MDA含量相较于空白对照组均有显著提升。[结论]天然桦木汁具有良好的抗氧化作用。 展开更多
关键词 桦木汁 斑马鱼胚胎 抗氧化性 自由基清除率 活性测定
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响应面法优化艾蒿多糖的提取工艺及其组成成分和体外抗氧化活性分析
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作者 张学凯 姜敏 +3 位作者 邢仲耘 韩志鹏 李佳莹 金晓 《动物营养学报》 北大核心 2025年第2期1271-1285,共15页
本试验旨在优化艾蒿多糖(AAP)的提取工艺,并研究其组成成分和体外抗氧化活性。在单因素试验的基础上,以AAP提取率作为响应值,通过响应面分析得出AAP最佳提取工艺;分析纯化后AAP的形状结构和单糖组成及分子质量;并通过测定1,1-二苯基-2-... 本试验旨在优化艾蒿多糖(AAP)的提取工艺,并研究其组成成分和体外抗氧化活性。在单因素试验的基础上,以AAP提取率作为响应值,通过响应面分析得出AAP最佳提取工艺;分析纯化后AAP的形状结构和单糖组成及分子质量;并通过测定1,1-二苯基-2-三硝基苯肼自由基(DPPH·)、羟自由基(·OH)、超氧阴离子自由基(O_(2)^(-)·)的清除率以及铁还原力,评估AAP的抗氧化活性。结果表明:1)通过响应面优化AAP的最佳提取工艺为液料比35∶1、酶解时间4 h、温度50℃,AAP提取率为12.46%,可溶性多糖含量为297.11 mg/g。2)纯化后AAP呈现出表面粗糙的立方体状颗粒、长链片状、圆球状等多种不规则块状形态;含阿拉伯糖、半乳糖、葡萄糖、木糖、甘露糖5种单糖,其分子质量比为1.68∶3.54∶80.81∶2.38∶11.59;平均分子质量为114.786 ku,属于吡喃糖。3)相同浓度下,AAP组DPPH·清除率和铁还原率在0.05~1.00 mg/mL浓度下均极显著低于阳性对照组(P<0.01),·OH清除率在0.40~1.00 mg/mL浓度下和O_(2)^(-)·清除率在0.20~1.00 mg/mL浓度下也极显著低于阳性对照组(P<0.01)。AAP对DPPH·、·OH和O_(2)^(-)·清除率的半数抑制浓度(IC_(50))分别为0.0552、0.8684和0.8392 mg/mL。综上所述,本研究优化了传统AAP提取工艺,并通过组分分析及体外抗氧化活性测定,发现AAP具有较强的抗氧化活性,为AAP作为饲料添加剂的开发与利用提供坚实的理论依据。 展开更多
关键词 艾蒿多糖 响应面 抗氧化活性 分子质量 自由基清除率 铁还原力
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Syntheses and Crystal Structures of [Na(H_2O)_(1/2)]X and NH_2(CH_2CH_3)_2X and Antioxidant Activity of the Former 被引量:1
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作者 刘彬 杨伯伦 《Chinese Journal of Structural Chemistry》 SCIE CAS CSCD 2009年第9期1112-1120,共9页
In order to enhance the water-solubility and biological utilization rate of chrysin, sodium 5,7-dihydroxylflavone-8-sulfonate (1, [Na(H2O)1/2]X, X = C15H9OSO3, 5,7-dihydroxylfla- vone-8-sulfonate) was synthesized ... In order to enhance the water-solubility and biological utilization rate of chrysin, sodium 5,7-dihydroxylflavone-8-sulfonate (1, [Na(H2O)1/2]X, X = C15H9OSO3, 5,7-dihydroxylfla- vone-8-sulfonate) was synthesized and its structure was identified on the basis of NMR, FT-IR and elemental analysis. The assembly of 5,7-dihydroxylflavone-8-sulfonate with diethylamide cation afforded diethylamide 5,7-dihydroxylflavone-8-sulfonate (2, NH2(CH2CH3)2X) which was characterized by FT-IR and elemental analysis. The crystal structures of 1 and 2 were determined by X-ray single-crystal diffraction analysis. The crystal of 1 is of triclinic system, space group P1, with a = 8.5628(13), b = 12.8916(19), c = 13.562(2) A, α = 82.494(1), β = 78.601(2), γ = 84.033(2)°, C30H20Na2O15S2, Z = 2, Mr = 730.59, V = 1450.3(4) A3, Dc = 1.673 g/cm3, F(000) = 748, p = 0.295 mm^-1, the final R = 0.0641 and wR = 0.1458. The crystal of 2 crystallizes in the triclinic system, space group Pi, with a = 7.689(2), b = 11.184(3), c = 11.734(3) A, α = 74.268(3), βl = 81.751(4), γ= 87.991(3)°, C19H21NO7S, Z = 2, Mr= 407.43, V= 961.2(4) A3, Dc = 1.408 g/cm3, F(000) = 428, p = 0.210 mm^-1, the final R = 0.0484 and wR = 0.1195. In 1, the three-dimensional structure is organized into organic and inorganic regions; the flavone skeletons are stacked into organic regions by π...π staeking interactions; inorganic regions are generated by Na-O coordination bonds among sulfonate groups, coordinated water molecules and NaI. The sulfonate groups play an important role as a bridge of inorganic and organic regions. One-dimensional chain structure of 2 is extended by N-H…O hydrogen bonds and π...π stacking interactions. Furthermore, the antioxidant activity of 1 was evaluated. The scavenging activity of 1 to DPPH free radical is better than that of the parent compound chrysin. 展开更多
关键词 5 7-dihydroxylflavone-8-sulfonate spectroscopic property crystal structure DPPH free radical scavenging activity
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Conformationally regulated“nanozyme-like”cerium oxide with multiple free radical scavenging activities for osteoimmunology modulation and vascularized osseointegration 被引量:2
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作者 Shusen Bao Dongmei Yu +8 位作者 Zhen Tang Hao Wu Hao Zhang Ning Wang Yichao Liu Hai Huang Chaozong Liu Xiaokang Li Zheng Guo 《Bioactive Materials》 SCIE CSCD 2024年第4期64-79,共16页
Given post-operative aseptic loosening in orthopedic disease treatment,osteointegration occurs at the bone-implant interface as a holistic process,including immunoregulation(e.g.,macrophage polarization),angiogenesis ... Given post-operative aseptic loosening in orthopedic disease treatment,osteointegration occurs at the bone-implant interface as a holistic process,including immunoregulation(e.g.,macrophage polarization),angiogenesis and osteogenesis in sequence.In order to achieve early rapid and satisfactory osseointegration,different nano-shaped(nanocone,nanopolyhedron and nanoflower abbr.NC,NP&NF)cerium oxide(CeO_(2-x))coatings,endowed with“nanozyme-like”activities for multiple free radical elimination and osteoimmunology regulation,were hydrothermally synthesized on titanium alloy(TC4).In vitro cell experiments showed that nano-CeO_(2-x) coated TC4 not only induced polarization of RAW264.7 cells toward M2 phenotype,but also promoted angiogenesis and vascularization of endothelial cells along with differentiation and mineralization of osteogenic precursor cells.Improvements in M2-polarized macrophage,angiogenesis,and bone regeneration were further confirmed in a rat femoral condyle model.Among the above three nano-morphologies,NF exhibited the best osseoinetegration.RNA sequencing and mechanism exploration suggested that the inhibition of PI3K-AKT signaling pathway was essential for immunomodulatory capacity of NF.In conclusion,it provided promising insights into the immunomodulatory exploitation of orthopedic implants. 展开更多
关键词 “Nanozyme-like”cerium oxide Durable redox activation free radical scavenging Osteoimmunology modulation Vascularized osseointegration
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核桃枝的抗氧化、抗菌及抗肿瘤活性研究
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作者 刘艳艳 张涛 +6 位作者 王媛媛 李明婉 丁申 杨超臣 陈圆圆 赖勇 张党权 《河南农业大学学报》 北大核心 2025年第1期57-67,共11页
【目的】评估核桃枝不同溶剂提取液的抗氧化、抗菌及抗肿瘤活性,为林业废弃物资源综合利用提供理论依据。【方法】采用不同的溶剂(水、丙酮和乙醇)进行提取,通过红外光谱和液相色谱-四级杆-高分辨串联质谱解析核桃枝中的化学成分;采用D... 【目的】评估核桃枝不同溶剂提取液的抗氧化、抗菌及抗肿瘤活性,为林业废弃物资源综合利用提供理论依据。【方法】采用不同的溶剂(水、丙酮和乙醇)进行提取,通过红外光谱和液相色谱-四级杆-高分辨串联质谱解析核桃枝中的化学成分;采用DPPH自由基、ABTS自由基和OH自由基清除法评估不同溶剂提取液的体外抗氧化能力;采用二倍稀释法检测提取液的抗菌能力;采用cell counting kit-8(CCK8)法检测提取液对宫颈癌细胞(Hela)、肝癌细胞(HepG2)、乳腺癌细胞(MCF-7)和胃癌细胞(SGC-7901)细胞的抗肿瘤活性。【结果】在3种溶剂提取液中,黄酮类、糖类、萜类及生物碱类等物质的含量均相对较高,生物医药类活性成分含量所占比例最高的是乙醇提取液,达到了86.88%;提取液的抗氧化能力随着质量浓度的升高而逐渐增强,抗氧化能力由强到弱依次是乙醇提取液、水提取液、丙酮提取液。乙醇提取液和丙酮提取液对蜡状芽孢杆菌和金黄色葡萄球菌都有较强的抑制作用,且乙醇提取液抑制大肠杆菌、沙门氏菌和枯草芽孢杆菌的效果强于丙酮提取液。提取液在抗肿瘤能力由强到弱依次是乙醇提取液、丙酮提取液、水提取液,且乙醇提取液对Hela、HepG2、MCF-7和SGC-7901细胞的抑制作用最显著,致死率分别为98.83%、99.08%、98.44%、98.74%。【结论】核桃枝含有多种抗氧化、抗菌和抗肿瘤活性成分,在功能食品或生物医药领域具有良好的开发潜能。 展开更多
关键词 核桃枝 活性成分 自由基清除 抗氧化 抗菌 抗肿瘤
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盐炙荔枝核化学成分及其抗氧化活性研究
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作者 尹蕊 杨兴 +7 位作者 董维茂 邓徐丽 王一谋 张洪川 朱奎霖 陈章贤 何红平 董发武 《中成药》 北大核心 2025年第2期480-486,共7页
目的研究荔枝核Litchi Semen盐炙品的化学成分及其抗氧化活性。方法盐炙荔枝核85%乙醇提取物采用硅胶、Sephadex LH-20、MCI、ODS、半制备HPLC进行分离纯化,根据理化性质及波谱数据鉴定所得化合物的结构。采用DPPH、ABTS+自由基清除法... 目的研究荔枝核Litchi Semen盐炙品的化学成分及其抗氧化活性。方法盐炙荔枝核85%乙醇提取物采用硅胶、Sephadex LH-20、MCI、ODS、半制备HPLC进行分离纯化,根据理化性质及波谱数据鉴定所得化合物的结构。采用DPPH、ABTS+自由基清除法评价其抗氧化活性。结果从中分离得到15个化合物,分别鉴定为去氢木香内酯(1)、菠萝香藤苷甲(2)、funingensin A(3)、(2 S)-pinocembrin-7-O-(6-O-a-L-rhamnopyranosyl-β-D-glucopyranoside)(4)、甘草素(5)、槲皮苷(6)、芦丁(7)、异鼠李素-3-O-β-芸香糖苷(8)、原花青素A2(9)、原花青素A1(10)、原儿茶酸乙酯(11)、5-羟甲基糠醛(12)、邻苯二甲酸-二(2-乙基-己基)酯(13)、烟酰胺(14)、(10 E,15Z)-9,12,13-trihydroxyoctadeca-10,15-dienoic acid(15)。化合物6~7、9~10对DPPH自由基表现出清除活性,其IC 50值分别为(12.929±1.232)、(14.104±0.946)、(10.417±1.736)、(6.944±0.030)μmol/L;化合物6~10对ABTS+自由基表现出清除活性,其IC 50值分别(21.952±0.577)、(25.683±0.625)、(22.970±1.336)、(20.210±1.435)、(18.725±0.324)μmol/L。结论化合物1、5、14~15首次从荔枝属中分离得到。化合物6~7、9~10有较强的体外抗氧化活性。 展开更多
关键词 盐炙荔枝核 化学成分 分离鉴定 抗氧化活性 DPPH自由基 ABTS+自由基
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Antioxidant Activity of 50 Traditional Chinese Medicinal Materials Varies with Total Phenolics 被引量:1
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作者 Zhengyou He Minbo Lan +2 位作者 Dongying Lu Hongli Zhao Huihui Yuan 《Chinese Medicine》 2013年第4期148-156,共9页
This study was designed to determine the total phenolic content of 50 herbs and to examine their antioxidant potential. In the sample preparation, 60% ethanol was chosen as the extraction solvent for the subsequent ex... This study was designed to determine the total phenolic content of 50 herbs and to examine their antioxidant potential. In the sample preparation, 60% ethanol was chosen as the extraction solvent for the subsequent experiments. Folin-Cicolteau phenol reagent and a colorimetric method were used to determine the total phenolic content of the selected herbs. The result showed that total phenolic content of those herbs ranged from 2 to 185 mg/g. In antioxidant assay, the ferric reducing/antioxidant power (FRAP) values ranged from 2 to 134 mg GAE/g;the IC50 values of DPPH?·, ·OH and ?scavenging were in the range of 0.06 - 5.50 mg/mL, 0.017 - 0.636 mg/mL and 0.050 - 0.681 mg/mL respectively. Flos caryophylli was the exceptant in the ?scavenging assay because there was no linear relation between the concentration and the scavenging percentage. Compared to gallic acid, ascorbic acid and butylated hydroxytoluene (BHT) in antioxidant assay as positive control, the most potential antioxidant herbs were Cacumen platycladi, Radix et Rhizoma rhei, Rhizoma rhodiolae crenulatae, and Rhizoma sanguisorbae with considerable content of phenolics. Especially, a positive and significant correlation was found between the total phenolic content and FRAP value or DPPH· scavenging percentage. 展开更多
关键词 TRADITIONAL CHINESE MEDICINAL Material Total Phenolics ANTIOXIDANT activity Ferric Reducing/Antioxidant Power free radical scavenging activity
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