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柚皮提取物的抗氧化活性研究 总被引:2,自引:0,他引:2
柚皮经乙醇浸提,上硅胶柱,分别用石油醚、乙酸乙酯、正丁醇、甲醇和水作溶剂洗脱其中有效成分,并采用DPPH体系、氮蓝四唑(NBT)光化还原法以及羟基氧化细胞色素C法对各洗脱物的抗氧化性进行研究。结果:柚皮中各相提取物对DPPH自由基、超氧自由基以及羟基自由基均有较强的清除效果,且正丁醇相对DPPH自由基以及羟基自由基均有较好的清除效果。而甲醇相、乙酸乙酯相对超氧自由基则有很好的清除效果。 相似文献
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基于天然绿色棉色素含有多酚类物质以及其结构的不稳定性,采用清除1,1?二苯基?2?苦基肼( DPPH)自由基法,探讨温度、光辐射、酸碱条件对绿色棉色素的抗氧化活性的影响。结果表明,高碱条件对绿色棉色素的抗氧化影响较大。经pH值为13的碱溶液处理后,色素的DPPH自由基清除率下降至2?97%,调回中性后,自由基清除能力恢复至原先的81?38%,说明碱性条件导致抗氧化性的消失大部分可以恢复。结合紫外光谱可以看出,碱性条件下色素主体结构不变,但部分组分结构发生了不可逆的破坏。光辐照对天然绿色棉色素的抗氧化活性有明显的影响,日晒5 d后,绿色棉色素自由基清除能力下降57?10%。高温150℃处理1 h对绿色棉色素的自由基清除能力影响不大。 相似文献
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酸浆宿萼抗氧化活性研究 总被引:3,自引:0,他引:3
采用有机溶剂萃取和柱层析相结合的方法提取与分离酸浆宿萼中的抗氧化成分,并对各分离组分的体外抗氧化活性进行研究.结果:酸浆宿萼提取物中乙酸乙酯相、正丁醇相、水相、组分Ⅰ、组分Ⅲ及组分Ⅳ对DPPH·自由基都有较高的清除率,在样品质量浓度为2mg/mL时清除率分别达到100%、99.74%、99.35%、82.09%、91.03%及71.63%;在样品质量浓度为2mg/mL时,水相、组分Ⅰ、组分Ⅲ和组分Ⅳ对金属的螯合率分别为78.51%、64.83%、77.69%和89.09%;除组分Ⅰ外其它分离物的质量浓度为2mg/mL时对·OH自由基的清除率均大于50%,其中组分Ⅳ的清除率最高,76.70%.说明酸浆宿萼具有较强的抗氧化活性,但不同组分的抗氧化的机理不同. 相似文献
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紫玉米色素的抗氧化活性研究 总被引:2,自引:1,他引:2
试验采用85∶15的80%乙醇与0.2 mol/L的柠檬酸溶液提取紫玉米色素,对其色素的光谱性质做了研究;通过建立DPPH.自由基、羟基自由基、超氧阴离子自由基、还原力、双氧水及Fe2+螯合能力体系等试验,测定并对比了紫玉米和抗坏血酸的抗氧化能力。结果表明:该色素为紫玉米色素,其具有较强的体外抗氧化能力,且清除自由基(DPPH.和.OH、O2.-)的能力明显优于阳性对照抗坏血酸。其色素粗提物在0.04mg/mL时,对DPPH.的清除率达到89.88%;对.OH的清除率达到84.87%;在0.035 mg/mL时,对O2.-的清除率达到85.82%。此外,紫玉米色素粗提物的总还原能力、双氧水清除能力略低于阳性对照抗坏血酸,Fe2+螯合能力约是EDTA的一半,并且其抗氧化能力的大小与紫玉米色素浓度高低相一致。 相似文献
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紫荆花红色素抑菌和体内抗氧化活性的研究 总被引:2,自引:0,他引:2
目的:探讨紫荆花红色素的抗菌活性和体内抗氧化活性。方法:牛津杯法和连续二倍稀释法考察紫荆花红色素对常见菌大肠杆菌、金黄色葡萄球菌、枯草芽孢杆菌、黑曲霉、啤酒酵母的抑菌活性及最小抑菌浓度;将小鼠分成正常对照和低、中、高剂量组进行灌胃实验,测定其血清和肝匀浆超氧化物歧化酶(SOD)活性和MDA含量。结果:紫荆花红色素对枯草杆菌、金黄色葡萄球菌、大肠杆菌、啤酒酵母具有一定的抑菌活性,最低抑菌浓度分别为0.5、0.5、1.0mg/mL和2.0mg/mL,对黑曲霉没有抑菌作用;使用紫荆花红色素溶液灌胃实验15d后,小鼠血清、肝匀浆SOD活性明显增强,MDA浓度明显降低。结论:紫荆花红色素具有抑菌和抗氧化活性,具有进一步研究的价值。 相似文献
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Antioxidant activity of several marine skin gelatins 总被引:1,自引:0,他引:1
Gelatins obtained from the skins of tuna and halibut, and from the tunics of jumbo flying squid were hydrolysed by Alcalase to produce antioxidant peptides. Hydrolysis yielded an increase in the antioxidant capacity of gelatins of around two-fold when measured by the Fe reducing capacity (FRAP) method and even more when measured by the ABTS radical scavenging method. When both squid and tuna gelatins were hydrolysed with different enzymes (collagenase, trypsin, pepsin), Alcalase and pepsin gave the hydrolysates with the highest and lowest ABTS radical scavenging ability, respectively. FRAP assay showed that the squid hydrolysates prepared using Alcalase were the most effective in reducing ferric ions, whereas trypsin gave rise to the tuna hydrolysates with the highest iron reducing ability. When the amino acid composition of the gelatins was related to the antioxidant properties, ABTS radical scavenging was observed to be negatively correlated to the total content of hydrophobic amino acids and imino acids in all the samples, while Fe reducing power (FRAP) was strongly correlated with Hyl and degree of hydroxylation. 相似文献
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以采集于新疆不同地区的20个野生苹果品种为研究对象,福林酚法测总多酚,分光光度计法测定总黄酮,DPPH、ABTS、还原能力法测定总抗氧化能力,相关系数法分析各个指标之间的相关性。结果显示,不同品种的野生苹果的总多酚、总黄酮及抗氧化活性之间具有显著差异,其中,HDM-23的总多酚含量最高(4714.33μmol没食子酸/100g鲜果),XY-31的总黄酮含量最高(2452.84mg芦丁/100g鲜果)。总多酚、总黄酮及抗氧化活性之间呈极显著(p<0.01)正相关,表明总多酚与总黄酮是野生苹果抗氧化活性的主要贡献物质。 相似文献
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Antioxidant activity of seed phenolics was studied in the following Lathyrus species: Lathyrus hirsutus, Lathyrus filiformis, Lathyrus sativus, Lathyrus cicera, Lathyrus angulatus, Lathyrus sphaericus, Lathyrus annuus, Lathyrus clymenum, Lathyrus pratensis, Lathyrus ochrus, Lathyrus aphaca, Lathyrus latifolius, Lathyrus setifolius, Lathyrus tingitanus and Lathyrus amphicarpos. Phenolic contents ranged from 3.8 mg/g meal in L. setifolius to 29.2 mg/g meal in L. sphaericus. In general, non-cultivated Lathyrus species contained higher phenolic contents than cultivated ones. A negative correlation between seed size and phenolic contents was observed and was related to the higher proportion of hulls in the smaller seeds. L. annuus possessed phenolics with highest specific antioxidant activity. These phenolics were more than two times more antioxidant than equivalent amounts of phenolics extracted from commercial chickpea, lupin or soy. On the other hand, L. aphaca possessed the highest antioxidant activity per mg of flour extract. This antioxidant activity was twice that observed in same amounts of extracted flours from commercial chickpea, lupin or soy. Results show that studied Lathyrus species are rich in phenolic compounds with higher antioxidant activity than phenolics of widely consumed legumes such as soy, chickpea or lupin. In conclusion, Lathyrus may represent an interesting source of phenolic compounds with high antioxidant activity that may be useful as natural antioxidants and contribute to revalorize the cultivation of these legumes. 相似文献
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《Food chemistry》2005,91(1):79-83
The antioxidant activities of brown pigment, extract of n-hexane and extract of supercritical carbon dioxide extraction of black sesame seeds were investigated in this study. Kinetics of anti-radical activity showed that the reaction between DPPH and brown pigment of sesame seed was rapid and reached the steady state in 10 min. Extracts from supercritical carbon dioxide extraction and n-hexane extraction reacted with DPPH slowly and the absorbance became stable after 35 min. However, α-tocopherol and trolox were rapid while the kinetic behaviour of BHA was intermediate. The brown pigment of sesame seed also showed a lower EC50 (13.5 μg ml−1) than the other two extracts and α-tocopherol, which was about 7–10 fold of the antioxidant activity of the supercritical carbon dioxide extract and the n-hexane extract. The ferric thiocyanate (FTC) method also showed that the brown pigment of sesame seed provided higher inhibition activity against lipid peroxidation at 200 μg ml−1 than did the supercritical carbon dioxide extract an n-hexane extract at 1 mg ml−1. However, the activities of the supercritical carbon dioxide extract and n-hexane extracts were significantly higher than that of α-tocopherol. In the linoleic acid system, the brown pigment of black sesame seed showed an equal antioxidant activity to BHA and higher than trolox and α-tocopherol. The results indicated that the brown pigment of sesame seed possessed excellent antioxidant activity. 相似文献
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以野生百合宜昌百合(3个不同产地)、渥丹、山丹、卷丹、岷江百合和传统食用的兰州百合为研究对象,采用福林-肖卡试剂法测其总多酚含量,Na NO2-Al Cl3比色法测定总黄酮含量,香草醛比色法测定其总黄烷醇含量,清除DPPH自由基、清除羟自由基、铜离子还原能力、抑制脂质过氧化物活性、金属离子螯合能力法评价百合鳞茎体外抗氧化活性。结果表明:野生百合鳞茎中的多酚类物质含量及抗氧化活性均显著高于兰州百合(p<0.05),同时百合鳞茎提取物抗氧化能力与提取物浓度间存在剂量-效应关系;百合鳞茎中多酚类物质与其抗氧化能力存在显著(p<0.05)或极显著(p<0.01)相关性,而且不同抗氧化方法间也存在显著相关性(p<0.05);此外,3个不同产地宜昌百合鳞茎中多酚类物质的组分、含量及其抗氧化活性存在显著差异(p<0.05),其中西乡县宜昌百合总酚、总类黄酮含量最高,并且具有最强的铜离子还原能力;留坝县宜昌百合总黄烷醇含量最高,对DPPH自由基的清除力、抑制脂质过氧化能力和金属螯合能力最强;而舟曲县宜昌百合仅对羟自由基清除力最强。这表明在野生百合开发利用时对其优良种源的筛选是非常必要的。 相似文献
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野生火棘果中黄色素的提取研究 总被引:1,自引:0,他引:1
野生火棘资源丰富,其果实不仅具有较高的营养价值和药用保健价值,而且还是一种重要的天然色素和果胶资源,可广泛用于食品、医药、化妆品等领域中。笔者通过研究首次发现红色火棘果中除了含有大量的红色素外,还含有较多的黄色素。本文以野生火棘果为原料,用已获到的提取红色素的方法将火棘果中的红色素提尽,然后用乙醇作提取剂从火棘果渣中提取天然黄色素。探讨了料液比、提取时间、提取次数和提取温度等因素对火棘果黄色素提取效果的影响,通过L9(34)正交实验确定了最佳工艺参数。结果显示,火棘果黄色素的最佳提取条件为:料液比1:9,提取时间75min,提取次数5次,提取温度60℃;黄色素的提取率为92.5%,产率为2.1%,色价为22.2。火棘果黄色素为脂溶性色素,其乙醇溶液在可见光区内的最大吸收波长为450nm。 相似文献