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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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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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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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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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New ESR Detection Method of Hydroxyl Radical Scavenging Activity of Blue Berry 被引量:3
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作者 Hiromi Kameya Mitsuko Ukai 《材料科学与工程(中英文B版)》 2011年第3期347-351,共5页
关键词 自由基清除活性 羟自由基 ESR 检测 羟基自由基 蓝莓 电子自旋共振 蓝浆果
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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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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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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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Study on Solid Fermentation and Antioxidant Function of Natto 被引量:1
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作者 Junxia SONG Hongbing QI Yanhong MAO 《Asian Agricultural Research》 2024年第1期32-36,共5页
[Objectives]To study the optimum conditions of solid fermentation of natto with antioxidant function as an index.[Methods]Single factor experiment and orthogonal experiment were designed to study the effects of temper... [Objectives]To study the optimum conditions of solid fermentation of natto with antioxidant function as an index.[Methods]Single factor experiment and orthogonal experiment were designed to study the effects of temperature,time,initial pH and inoculum amount on the antioxidant activity of natto solid fermentation.The optimum conditions of natto solid fermentation were determined and the antioxidant ac-tivity of natto extract was compared.[Results]The optimal fermentation conditions were as follows:temperature 32℃,initial pH 7.0,inocu-lation amount 8%,fermentation time 32 h.The hydroxyl radical scavenging rate of natto solid fermentation crude extract was the highest,which was 82.7%.The optimized nato fermentation extract showed stronger scavenging ability for-OH and O,:,and showed obvious dose-effect relationship.ICso was 3.63 and 4.24 mg/mL,respectively,and the scavenging efficiency was 1.3 and 1.9 times higher than that of the unoptimized fermentation extract,respectively.[Conclusions]Natto is rich in nattokinase and other functional factors,and its antioxidant ac-tivity can be improved by optimizing fermentation technology,so that natto products can be widely used,including cosmetic raw materials,nat-to skin care soap,health food and medicine,etc.,and have a broader development prospect. 展开更多
关键词 NATTO Solid fermentation hydroxyl radical scavenging rate Antioxidant 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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荧光素-Fenton体系荧光法测定中草药抗氧化活性 被引量:6
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作者 赵二劳 王迎进 +2 位作者 贾楠 赵三虎 范建凤 《分析科学学报》 CAS CSCD 北大核心 2015年第6期886-888,共3页
荧光素能发出强的荧光,但在碱性介质中,Fenton体系产生的·OH能迅速氧化荧光素使其荧光猝灭。加入抗氧化剂,可清除部分·OH,从而使荧光猝灭程度降低,荧光猝灭降低的程度与加入抗氧化剂的量具有量效关系,据此建立了一种测定中草... 荧光素能发出强的荧光,但在碱性介质中,Fenton体系产生的·OH能迅速氧化荧光素使其荧光猝灭。加入抗氧化剂,可清除部分·OH,从而使荧光猝灭程度降低,荧光猝灭降低的程度与加入抗氧化剂的量具有量效关系,据此建立了一种测定中草药抗氧化活性的新方法。应用该方法测定了9种常见中草药的抗氧化性,其中甘草、菊花、金银花、葛根和山楂抗氧化性较强。 展开更多
关键词 荧光光度法 荧光素 中草药 羟基自由基 抗氧化活性
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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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苯甲酸-Fenton体系荧光法测定中草药抗氧化活性 被引量:6
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作者 白建华 程琳 +1 位作者 武宇芳 赵二劳 《分析科学学报》 CAS CSCD 北大核心 2011年第5期675-677,共3页
利用Feton体系产生羟自由基,能与苯甲酸反应生成具有强荧光的产物,加入抗氧化剂可有效清除羟自由基,导致体系荧光强度降低。据此建立了筛选抗氧化剂的荧光新体系。应用所建立的方法测定了葛根、吴茱萸和黄连三种常见中草药的抗氧化活性... 利用Feton体系产生羟自由基,能与苯甲酸反应生成具有强荧光的产物,加入抗氧化剂可有效清除羟自由基,导致体系荧光强度降低。据此建立了筛选抗氧化剂的荧光新体系。应用所建立的方法测定了葛根、吴茱萸和黄连三种常见中草药的抗氧化活性。结果表明,当中草药的浓度为0.4mg(dry weight)/mL时,葛根、吴茱萸、黄连对羟基自由基的清除率分别为53.17%、58.58%和67.80%。 展开更多
关键词 荧光光度法 中草药 羟基自由基 苯甲酸 抗氧化活性
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气相色谱法测定Fenton反应产生的羟基自由基及其清除作用 被引量:4
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作者 王炳娟 卢青 邹洪 《理化检验(化学分册)》 CAS CSCD 北大核心 2009年第1期88-90,共3页
提出了一种测定羟基自由基的气相色谱法。由Fenton反应产生的羟基自由基氧化二甲亚砜(DMSO),生成的甲醛经2,4-二硝基苯肼(DNPH)衍生化并用四氯化碳萃取。所得产物(甲醛-DNPH)利用HP-5毛细管柱进行分离,氢火焰离子化检测器检测,通过测定... 提出了一种测定羟基自由基的气相色谱法。由Fenton反应产生的羟基自由基氧化二甲亚砜(DMSO),生成的甲醛经2,4-二硝基苯肼(DNPH)衍生化并用四氯化碳萃取。所得产物(甲醛-DNPH)利用HP-5毛细管柱进行分离,氢火焰离子化检测器检测,通过测定甲醛-DNPH的峰面积可间接定量羟基自由基的产生量。拟定的方法测定了几种羟基自由基清除剂的浓度。此法可用于羟基自由基清除剂的筛选。 展开更多
关键词 羟基自由基 清除剂 气相色谱法
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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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氧氟沙星-Fenton体系荧光法测定和评价中草药抗氧化活性 被引量:1
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作者 王桂林 郭敏敏 +1 位作者 吕雅娟 赵二劳 《分析科学学报》 CAS CSCD 北大核心 2023年第4期497-500,共4页
研究利用荧光法测定和评价中草药抗氧化活性。氧氟沙星(Ofloxacin,OFL)能产生强荧光,在酸性环境中,Fenton反应产生的羟基自由基(·OH)能氧化OFL使其荧光猝灭,加入抗氧化剂或含有抗氧化成分的中草药可清除·OH使与OFL反应的·... 研究利用荧光法测定和评价中草药抗氧化活性。氧氟沙星(Ofloxacin,OFL)能产生强荧光,在酸性环境中,Fenton反应产生的羟基自由基(·OH)能氧化OFL使其荧光猝灭,加入抗氧化剂或含有抗氧化成分的中草药可清除·OH使与OFL反应的·OH量减少,导致OFL荧光猝灭程度减弱。OFL荧光猝灭程度与加入抗氧化剂量或中草药中抗氧化成分的量呈定量关系,据此建立了一种测定和评价中草药抗氧化活性的新方法。应用该法测定和评价了7种常见中草药抗氧化活性,其中夏枯草、连翘和黄连的抗氧化活性较强。该方法操作简单,体系稳定,可用于中草药抗氧化活性测定和评价。 展开更多
关键词 荧光法 氧氟沙星 中草药 羟基自由基 抗氧化活性
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