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1.
The aqueous extract of Phellodendron amurense Rupr. (Amur Cork Tree) provides a rich source of antioxidants and chemical compounds, and can be used for food and wood preservative materials. In this study, we characterized the chemical composition of this extract by GC and GC/MS. The antioxidant capacity was evaluated using a variety of antioxidant assays (superoxide radical, hydroxyl radical, nitric oxide radical, and DPPH radical scavenging activity). Additionally, total polyphenolic content was determined. Phenolic acids and acetone derivatives were major compounds of the extract capable of scavenging the DPPH free radical and reducing ferric ions. DPPH and ferric ion reduction results were strongly correlated with total phenolic content of the extract which also exhibited strong nitric oxide, hydroxyl radical scavenging and superoxide anion radical scavenging activities. 相似文献
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The Argyreia cymosa bark extracts were subjected to in vitro antioxidant activity with different methods. The petroleum ether extract has shown antioxidant activity in ABTS, nitric oxide, hydroxyl radical (by p-NDA) and lipid peroxidation methods. The ethyl acetate extract has shown antioxidant activity in DPPH, H(2)O(2) and hydroxyl radical (by deoxyribose) scavenging methods. 相似文献
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自由基具有强氧化性,机体衰老及多种疾病如肿瘤、炎症、神经退行性疾病、动脉粥样硬化等的诱发促进机制都与自由基有关[1]。自由基的减少,不仅要靠自身的清除系统,还需要外部抗氧化剂的协助。近年来,关于合成抗氧化剂的副作用受到人们更多的关注,因此,寻找安全、高效的植物源类抗氧化剂,已成为食品领域研究的热点。楸树(Catalpa bungei C.A.Mey.)为紫葳科(Bignoniaceae)梓属植物,落叶乔木,《本草纲目》记载楸树树皮、叶具有药 相似文献
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The influence of various solvents on the yield of polyphenols from defatted marigold residue, the antioxidant activity of the extracts and the composition of antioxidant compounds in the extracts were investigated. The content of total phenolics and flavonoids in the extracts was significantly varied with different solvents (P<0.05) and the extract by ethyl alcohol (EtOH)/water (7:3, v/v) has the highest content of total phenolics and flavonoids, 62.33 mg gallic acid equivalents (GAE)/g and 97.00 mg rutin equivalent (RE)/g, respectively. The antioxidant activity of the extracts was evaluated by radical (2,2'-azino-bis-(3-ethylbenzothiazoline-6-sulfonic acid) (ABTS), 1,1-diphenyl-2-picrylhydrazyl (DPPH)) scavenging and ferric reducing antioxidant power (FRAP) assays. The results of the correlation analysis showed that the antioxidant activity was well correlated with the content of total phenolics and flavonoids (R2>0.900). Antioxidant components in the extracts were identified by combined on-line HPLC-ABTS·+ post-column assay and HPLC-DAD-MS method. Gallic acid, gallicin, quercetagetin, 6-hydroxykaempferol-O-hexoside, patuletin-O-hexoside and quercetin were the dominant antioxidant compounds in the extracts, and quercetagetin was identified as the strongest antioxidant capacity. 相似文献
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采用气相色谱-质谱法对不同化学类型樟树叶精油组成进行分析,对比4种樟树叶精油的成分差异;采用DPPH、ABTS、FRAP法对樟树叶精油的体外抗氧化活性进行评价,并使用丁基羟基茴香(BHA)作为阳性对照。研究结果表明:4种类型樟树叶精油共检测出46种主要化学成分,其中,异樟叶精油检测出35种化学成分,主要成分异橙花叔醇为29.48%;芳樟叶精油检测出33种成分,主要成分芳樟醇为71.91%;脑樟叶精油检测出33种化学成分,主要成分樟脑为46.28%;油樟叶精油中共检测出33种化学成分,主要成分1,8-桉叶油素为30.31%。4种樟树叶精油均具有一定的抗氧化活性,且随着精油浓度增加抗氧化能力增强,但其抗氧化能力均低于BHA。其中,脑樟叶精油的DPPH自由基清除能力及Fe 3+还原能力最强,当质量浓度为8 g/L时,脑樟叶精油的DPPH自由基清除率为30.34%±1.25%,FRAP值为(1.44±0.13)mmol/L;而异樟叶精油的ABTS自由基清除能力最强,当质量浓度为8 g/L时,异樟叶精油的ABTS自由基清除率为14.93%±2.32%。 相似文献
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山楂叶总黄酮清除DPPH和超氧阴离子自由基的活性研究 总被引：4，自引：0，他引：4
以山楂秋日落叶为原料,70%乙醇为溶剂,提取得到山楂叶总黄酮。以芦丁和VC为对照,采用分光光度法研究了山楂叶总黄酮对DPPH自由基和超氧阴离子自由基的体外清除活性。结果表明,山楂叶总黄酮对DPPH自由基和超氧阴离子自由基均具有一定的清除作用。对DPPH自由基的清除率随加入量的增加而增加,当加入量为2 mg时,清除率为50.29%;而对超氧阴离子自由基的清除在加入量为1.2 mg时达到最高值27.36%。芦丁对二自由基的最高清除率分别为63.83%和32.55%;而VC则分别为69.93%和99.04%。经比较发现,山楂叶总黄酮的清除自由基活性稍低于芦丁,远低于VC。 相似文献
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紫甘薯花色苷的组分及抗氧化活性研究(英文) 总被引：2，自引：0，他引：2
对紫甘薯花色苷的化学成分和抗氧化活性进行了研究.研究采用大孔树脂AB-8纯化紫甘薯花色苷,高效液相色谱-2极管阵列法(HPLC-DAD)分析表明,纯化后的提取物中共含有11种花色苷,其中主要成分为酰化的矢车菊素和芍药素.并测定了紫甘薯总花色苷在DPPH自由基清除体系、超氧阴离子体系、还原力和亚油酸体系的抗氧化活性.在质量浓度均为0.5g/L时,花色苷、L-AA和 BHT的还原力分别为0.572、0.460 和0.121,花色苷的清除DPPH自由基的半数抑制浓度(IC50)和清除超氧阴离子IC50分别为6.94和3.68mg/L,表明花色苷还原能力强,并能有效地清除DPPH自由基和超氧阴离子.此外,紫甘薯花色苷能较好地抑制脂质过氧化. 相似文献
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Antioxidant activity of Pyrrosia petiolosa 总被引：1，自引：0，他引：1
Hsu CY 《Fitoterapia》2008,79(1):64-66
The ethanol extract of Pyrrosia petiolosa showed an antioxidant activity as determined by free radical scavenging, superoxide radical scavenging, lipid peroxidation, and hydroxyl radical-induced DNA strand scission assays. 相似文献
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不同蓝莓品种果实抗氧化能力比较研究 总被引：1，自引：0，他引：1
以引种栽培于湖南省森林植物园的5个蓝莓品种‘灿烂’、"蓝月"、‘库帕’、‘伯克利’、‘布里吉塔’为试验材料,测定其采收后的果实中可溶性多糖、Vc、还原型谷胱甘肽、总花色苷4种抗氧化物质的含量,并测定其果实中代表抗氧化活性的DPPH自由基清除能力和SOD的活性,同时分析比较4种抗氧化物质与DPPH自由基清除能力之间的相关性。结果表明:5个品种中‘蓝月’的Vc含量、还原型谷胱甘肽含量、总花色苷含量、DPPH自由基清除能力以及SOD活性均显著高于其他4个品种(P0.05);Vc含量、还原型谷胱甘肽含量以及总花色苷含量与DPPH自由基清除能力成显著正相关关系(P0.05);可溶性多糖含量与DPPH自由基清除能力相关性较弱。说明5个品种中‘蓝月’的抗氧化能力最强。 相似文献
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Non-isothermal, aqueous treatments of Pinus radiata wood were carried out to reach maximal temperatures in the range 210–240°C, and the liquors from the treatments were analysed for phenolic content and antioxidant activity using several tests (,-diphenyl--picrylhydrazyl (DPPH) radical scavenging, hydroxyl radical scavenging, Trolox equivalent antioxidant capacity, -carotene bleaching and reducing power). Increased severity resulted in increased yields in phenolics (up to 1.5 g phenolic compounds/100 g oven-dry wood) and improved antioxidant activity. The DPPH radical scavenging capacity of compounds present in autohydrolysis liquors and the -carotene bleaching ability of the compounds extracted with ethyl acetate from liquors were higher than those of synthetic antioxidants. The fractions solubilised in autohydrolysis treatments were also effective as hydroxyl and ABTS radical scavengers. The autohydrolysis liquors and their ethyl acetate soluble fraction showed reducing power in the range reported for extracts from other natural sources. 相似文献
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北方主要越橘栽培品种果实品质及抗氧化能力的比较 总被引：1，自引：0，他引：1
以北方主要越橘栽培品种为材料,进行了果实品质、抗氧化物质及其能力的比较分析。结果表明,6个品种中北蓝（Northblue）果形最大,蓝丰（Bluecrop）果实总糖含量最高,美登（Blomidon）果实的可溶性固形物和总酸含量最高。越橘果实的主要抗氧化物质为花色苷、酚类和类黄酮化合物,其中,北蓝果实的花色苷和总黄酮含量最高,北陆（Northland）的多酚含量最高,伯克利（Berkeley）的花色苷、总黄酮和多酚含量均最低。通过总还原力、DPPH和清除超氧自由基的检测,蓝丰、北蓝、北陆的抗氧化能力较强,伯克利的抗氧化能力最弱。 相似文献
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Radical scavenging activity and composition of raspberry (Rubus idaeus) leaves from different locations in Lithuania 总被引：1，自引：0，他引：1
Raspberry (Rubus idaeus) leaves, collected in different locations of Lithuania were extracted with ethanol and the extracts were tested for their antioxidant activity (AA) by using ABTS(.)(+) decolourisation and DPPH(.) scavenging methods. All extracts were active, with radical scavenging capacity at the used concentrations from 20.5 to 82.5% in DPPH(.) reaction system and from 8.0 to 42.7% in ABTS(.)(+) reaction. The total amount of phenolic compounds in the leaves varied from 4.8 to 12.0 mg of gallic acid equivalents (GAE) in 1 g of plant extract. Quercetin glucuronide, quercetin-3-O-glucoside and rutin were identified in the extracts. 相似文献
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Zeen Huang Koh Hashida Rei Makino Fumio Kawamura Kuniyoshi Shimizu Ryuichiro Kondo Seiji Ohara 《Journal of Wood Science》2009,55(3):225-229
Heartwoods of 22 African tropical wood species were extracted with methanol and the contents of total phenolic compounds in
these extracts were measured. Three bioassays were conducted to evaluate the antioxidant activity, tyrosinase inhibitory activity,
and antifungal activity of the methanol extracts. The results indicated that the extracts from 13 species exhibited high antioxidant
potential, and their inhibitory concentrations that caused 50% scavenging of the 1,1-diphenyl-2-picrylhydrazyl (DPPH) radical
(IC50) were less than 10 μg/ml. The crude extract from Cylicodiscus gabunensis showed the highest antioxidant activity, and was even higher than that of (+)-catechin, which is known as a potent antioxidant.
There was a good correlation between the antioxidant activity and the content of total phenolic compounds, indicating that
phenolic compounds played a predominant role in the antioxidant property of the wood extracts. Among all 22 species, only
1 species, Milicia excelsa, contained extractives that showed very high tyrosinase inhibitory activity. The extracts from 9 species showed high antifungal
activity. No consistent relationship was observed between the tyrosinase inhibitory activity or antifungal activity and the
content of total phenolics in the extracts.
Part of this article was presented at the 56th Annual Meeting of the Japan Wood Research Society, Akita, August 2006 相似文献
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The total phenolic content of 31 species of fern plants was determined, and their antioxidant activities were assessed by DPPH radical scavenging analysis. 相似文献
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Tian-Xiao Meng Shoko Furuta Sayaka Fukamizu Ryoko Yamamoto Hiroya Ishikawa Enos Tangke Arung Kuniyoshi Shimizu Shoji Ohga Ryuichiro Kondo 《Journal of Wood Science》2011,57(5):452-458
Pleurotus citrinopileatus Singer has recently become a popular delicacy in East Asian countries. We prepared a methanol extract, soluble fractions
from the methanol extract, and a hot water extract of the fruiting bodies of P. citrinopileatus. The biological activities such as melanin biosynthesis inhibition, tyrosinase inhibition, antioxidant activities [1,1-diphenyl-2-picrylhydrazyl
(DPPH) radical scavenging, oxygen radical absorbance capacity (ORAC), and superoxide dismutase (SOD)-like activity], antibacterial
activities, and antihyaluronidase activities of these extracts were evaluated. We found that the n-hexanesoluble, diethyl ether-soluble, and ethyl acetate-soluble fractions exhibited melanin biosynthesis inhibition in B16
melanoma cells, as well as antioxidant (ORAC) and antibacterial activities. However, the n-butanol-soluble and water-soluble fractions and the methanol and hot water extracts exhibited antioxidant (DPPH radical scavenging,
SOD-like activity) and antihyaluronidase activities. These results indicate that the fruiting bodies of P. citrinopileatus have the potential to be used as an ingredient in skin cosmetics. 相似文献
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Sheng-Yang?Wang Jyh-Horng?Wu Sen-Sung?Cheng Chiu-Ping?Lo Hsing-Ning?Chang Lie-Fen?Shyur Shang-Tzen?Chang
Calocedrus formosana Florin (Cupressaceae) is an endemic tree to Taiwan. To evaluate the antioxidant activity of the plant extracts from heartwood, bark, and leaf of C. formosana, assays for 1,1-diphenyl-2-picrylhydrazyl (DPPH) radical and superoxide anion scavenging activities, as well as prevention of DNA strand cleavage were performed in this study. Similar IC50 values against the DPPH radical were found for the heartwood and bark extracts at approximately 23µg/ml. Moreover, the heartwood extract exhibited the highest inhibitory activity against superoxide radicals among the test samples; a 2.3-fold lower value of IC50 for superoxide radical inhibition was found in the heartwood extract relative to that of (+)-catechin. Much less effect on inhibition of DPPH and superoxide radicals was found from the leaf extract of C. formosana. More than 70% of superoxide radicals were inhibited in the presence of 10µg/ml heartwood extract, whereas only 15% inhibition was obtained from the leaf extract. The heartwood extract, at a dose of approximately 0.5mg/ml, apparently completely prevented the X174 supercoiled DNA cleavage induced by ultraviolet photolysis of H2O2, as judged by agarose gel electrophoresis. This report also suggests that the antioxidant activities of the plant extracts of C. formosana are in good correlation with their phenolic contents. 相似文献
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A new flavone glycoside, apigenin 5-O-alpha-L-rhamnopyranosyl-(1-->3)-beta-D-glucopyranoside (1), along with four known flavonol glycosides (2-5), were isolated from the leaf of Cephalotaxus koreana. The new glycoside 1 showed inhibitory activity in superoxide radical scavenging assay with IC(50) value of 13.0 microM, while it showed weak activity in 1,1-diphenyl-2-picrylhydrazyl (DPPH) free radical scavenging assay. Compounds 2-5 exhibited antioxidant activity in scavenging DPPH and superoxide radicals with IC(50) values ranging from 5.7 to 22.3 microM. 相似文献