共查询到20条相似文献，搜索用时 234 毫秒
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黑荆树树皮原花色素生物活性的研究 总被引：3，自引：2，他引：1
对黑荆树树皮中原花色素的提取及生物活性进行了研究.实验分别以水、甲醇和乙醇作为提取溶剂,对黑荆树皮中原花色素的提取进行了探讨,通过测定其总抽出物含量和原花色素粗提物得率的影响,确定了适宜的提取条件,并重点对原花色素生理活性包括抗肿瘤和抗氧化活性进行了评价.利用MTT比色法对原花色素抗肿瘤活性进行了测定,利用清除DPPH自由基能力测定了其抗氧化能力.实验结果表明,黑荆树树皮是一种富含原花色素的植物资源.提取溶剂选择性试验结果表明,乙醇作为提取溶剂,不仅可以得到较高提取率的原花色素,而且所得原花色素粗提物具有较高的生理活性.黑荆树树皮原花色素适宜提取工艺条件为:溶剂浓度 70%,提取温度 60 ℃,液料比7∶1.体外癌细胞培养的抑制作用测试结果显示,黑荆树树皮提取得到的原花色素粗产品对人早幼粒白血病细胞HL-60有中效,分别对人低分化胃腺癌细胞BGC-823和人肝癌细胞BEL-7402有弱效.自由基清除能力测定结果显示黑荆树树皮中原花色素提取物有很强的抗氧化活性. 相似文献
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《西部林业科学》2020,(2)
为了研究桦褶孔菌不同溶剂萃取物的体外抗氧化能力及总黄酮含量、多酚含量与抗氧化活性之间的相关性,采用不同极性溶剂对桦褶孔菌75%乙醇提取物进行萃取,得到石油醚相、乙酸乙酯相、正丁醇相和水相萃取物,测定不同萃取相中总黄酮和多酚的含量,研究各萃取相清除DPPH自由基、ABTS自由基、羟自由基和超氧阴离子自由基能力,并分析总黄酮和多酚含量与抗氧化活性的相关关系。结果表明,石油醚相中的总黄酮含量最高,为(214.62±3.24)mg/g,乙酸乙酯相中多酚含量最高,为(50.34±30.13)mg/g。桦褶孔菌不同溶剂萃取物均具有一定的抗氧化活性,其中正丁醇相萃取物清除DPPH自由基和超氧阴离子自由基活性最强,其EC_(50)分别为(66.09±1.82)μg/mL和(47.94±1.68)μg/mL;正丁醇相萃取物浓度在0.5mg/mL时清除DPPH自由基的能力和V_C相当;乙酸乙酯相萃取物清除超氧阴离子自由基活性仅次于正丁醇相萃取物,EC_(50)为(93.63±1.97)μg/mL。相关性显示桦褶孔菌不同萃取相中总黄酮和多酚含量与抗氧化活性呈现较好的相关关系(P0.05)。研究结果表明正丁醇相和乙酸乙酯相萃取物具有较强的抗氧化活性,可为桦褶孔菌活性成分的分离奠定理论依据。 相似文献
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棕榈花苞抗氧化成分提取及体外抗氧化活性研究 总被引：1，自引：0，他引：1
《林业工程学报》2017,(1)
为研究棕榈花苞中抗氧化成分的最佳提取工艺及体外抗氧化活性,在单因素试验的基础上,选取乙醇体积分数、液料比和提取时间为考察因素,以DPPH·自由基清除率和ABTS·+自由基阳离子清除率等抗氧化能力指标为衡量指标,采用Box-Behnken试验设计来优化提取工艺。在最佳提取工艺下得到提取物,测定其多酚和黄酮的含量,并以多项抗氧化指标综合评价其体外抗氧化能力。结果表明:当乙醇体积分数78%,液料比28∶1(m L∶g),提取时间64 min,提取温度80℃时,棕榈花苞提取物DPPH·清除率为92.05%,ABTS·+清除率为63.82%,提取物中总酚含量4.72%,得率为15.08 mg/g;总黄酮含量3.63%,得率为11.67 mg/g。本试验条件下每100 g棕榈花苞(以干质量计)的体外抗氧化能力相当于2 990~6 262 mg Vc,棕榈花苞的体外抗氧化能力IC50为0.115~5.795 mg/m L,具备一定的抗氧化能力。 相似文献
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以花楸果为原料，对花楸果多酚进行乙醇提取，分别研究料液比、乙醇浓度、提取时间和温度对花楸果多酚物质提取率的影响，获得最佳提取工艺参数。并通过研究花楸果多酚提取物对羟自由基、DPPH自由基、过氧化氢等的清除能力，同时与相同浓度的抗坏血酸进行比较，对其进行抗氧化性的研究。由结果可知，最佳提取工艺参数为：料液比1∶25,40%乙醇浓度，40℃下提取90 min,该条件下多酚得率达6.73%。通过比较花楸果多酚提取物与相同浓度的抗坏血酸的抗氧化性，确定花楸果多酚提取物的抗氧化能力较抗坏血酸要弱，但仍具有很强的抗氧化能力。 相似文献
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《林产化学与工业》2018,(5)
采用超声波-微波辅助法优化杜仲叶中总多酚提取工艺,并考察其抗氧化活性。通过Plackett-Burman试验考察了乙醇体积分数、料液比、微波功率、微波处理时间、超声波功率和超声波处理时间6个因素对杜仲叶总多酚提取效果的影响,筛选得到乙醇体积分数、料液比、微波功率和超声波处理时间4个显著影响因素,在此基础上,通过最陡爬坡试验和响应面试验得到最佳提取条件为:乙醇体积分数为46%,料液比为1∶20.70(g∶mL),微波功率为154 W,微波处理时间140 s,超声波功率350 W,超声波处理时间为31 min。在此条件下提取2次总多酚得率达8.491%,与传统溶剂提取法相比,总多酚得率提高33.57%。利用最优工艺得到总多酚提取物,其体外抗氧化试验表明:杜仲叶总多酚提取物对1,1-二苯基-2-三硝基苯肼自由基(DPPH·)、2,2-联氮-二-3-乙基-苯并噻唑-6-磺酸自由基(ABTS·)和羟基自由基(·OH)均有较强的清除能力,其半数抑制质量浓度(IC_(50))分别为31.21、24.50和311.8 mg/L,抗氧化活性与BHT相当,低于Vc。 相似文献
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木麻黄树皮提取物的清除羟自由基活性 总被引：2，自引：0，他引：2
考察了4种木麻黄树皮水提取物的化学组成及其对绝对分子质量分布的影响因素,用邻二氮菲-Fe2+氧化法测定了不同树种和不同溶剂提取物对羟自由基的清除率.结果表明,不同提取溶剂对木麻黄树皮提取物组成、绝对分子质量分布影响较大.盐酸-丙酮-水溶液(HAW,1.0%盐酸与丙酮溶液质量比7∶3)作提取溶剂可大幅提高提取物的总固形物和多酚含量.应用激光散射-凝胶渗透色谱(SEC)技术测得山地木麻黄树皮HAW提取物的绝对分子质量为5×102～2×105.木麻黄提取物清除羟自由基的活性高,质量浓度为2g/L的山地木麻黄树皮HAW提取物对羟自由基的清除率高达81.6%.提取物的组成影响其清除羟自由基活性. 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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The aim of this study was to investigate antioxidant capacity of nine Fabaceae species collected on the mountains of Serbia and Montenegro. Antioxidant assays with various reaction mechanisms were used, including total phenolic content by Folin-Ciocalteu, DPPH radical scavenging capacity, Trolox equivalent antioxidant capacity (TEAC) values by ABTS radical cation and inhibition of liposome peroxidation. The investigated plants exhibited strong antioxidant capacity in all the tested methods, and among them, Lathyrus binatus, Trifolium pannonicum, and Anthyllis aurea were found to be the most active. 相似文献
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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 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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Total phenolic content, reducing power, antioxidant and free radical scavenging activities of ethanol extracts of five mosses were determined in vitro. No correlation between the total phenolic content and antioxidant or scavenging activities was found. 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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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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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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Propolis, a natural product produced by the honeybee, has been used for thousands of years in folk medicine for several purposes. The extract contains amino acids, phenolic acids, phenolic acid esters, flavonoids, cinnamic acid, terpenes and caffeic acid. It possesses several biological activities such as antiinflammatory, immunostimulatory, antiviral and antibacterial. The exact mode of physiological or biochemical mechanisms responsible for the medical effects, however, is yet to be determined. In this work, we have investigated the antioxidant activity of a propolis extract deprived of caffeic acid phenethyl ester (CAPE). In addition, the activity of CAPE and galangin was also examined. Propolis extract (with and without CAPE) and its active components showed a dose-dependent free radical scavenging effect, a significant inhibition of xanthine oxidase activity, and an antilipoperoxidative capacity. Propolis extract with CAPE was more active than propolis extract without CAPE. CAPE, used alone, exhibited a strong antioxidant activity, higher than galangin. The experimental evidence, therefore, suggests that CAPE plays an important role in the antioxidant activity of propolis. 相似文献