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复叶耳蕨渣总黄酮转化提取与DPPH自由基清除活性的研究
复叶耳蕨 土壤真菌 固体发酵 DPPH自由基清除
2016/6/27
究复叶耳蕨渣的 土 壤真菌发酵转化提取其总黄酮和清除 DPPH 自由基活性 。 复叶耳蕨渣直筛发酵用优势
菌株 ; 通过单因素和正交实验 L9 (3#) 优化总黄酮提取 ， DPPH 法评价转化前后总黄酮抗氧化活性 。 研究得到优势菌株
F& 发酵复叶耳蕨渣后黄酮得率为 （ 0.893% ±0.035% ) ， 较未发酵时总黄酮得率提高了 27.0% ， 差异显著 。 F2 发酵复叶
耳蕨渣...
不同二氢杨梅素含量的显齿蛇葡萄提取物的抗菌活性与清除DPPH自由基能力研究
显齿蛇葡萄提取物 二氢杨梅素 抗菌活性 清除DPPH
2016/12/24
研究不同二氢杨梅素含量的显齿蛇葡萄提取物的抗菌活性与清除DPPH自由基能力。选取17种二氢杨梅素 含量不同的显齿蛇葡萄，使用乙醇超声辅助法获得各个样品的提取物；采用药敏滤纸片法和二苯代苦味酰基自由基 (DPPH.)体系分别研究提取物以及相同含量的二氢杨梅素纯品的抗菌活性和清除DPPH自由基能力。结果表明：17 种提取物的抗菌活11■生和清除DPPH自由基能力随着提取物中二氢杨梅素含量的增加而增强，...
Effect of cooking methods on total phenolic and carotenoid amounts and DPPH radical scavenging activity of fresh and frozen sweet corn (Zea mays) kernels
Zea mays L. cooking process phenolics β-carotene antioxidan
2014/2/24
We evaluated the effect of three different cooking methods on antioxidant content and radical scavenging activity of sweet corn. Both fresh and frozen sweet corn kernels were boiled, microwaved, and s...
狗脊中化学成分及其对DPPH清除作用研究
3-O-咖啡酰-D-葡萄糖 结构研究
2012/12/17
研究狗脊的化学成分,探讨其对二苯代苦味基肼自由基(DPPH)的清除作用。 方法: 采用硅胶色谱、凝胶色谱、高效液相色谱等技术对狗脊70%乙醇提取物进行分离纯化,通过波谱方法鉴定其结构,并对化合物进行清除DPPH活性试验。 结果: 从狗脊70%乙醇提取物中分离得到10个成分,分别为1-O-咖啡酰-β-D-葡萄糖( 1 ),6-O-咖啡酰-D-葡萄糖( 2 ),3-O-咖啡酰-D-葡萄糖( 3 ),3...
铁皮石斛不同部位黄酮碳苷类成分及清除DPPH自由基能力比较研究
铁皮石斛 黄酮碳苷 不同部位 DPPH
2012/6/15
对铁皮石斛根、茎、叶和花中黄酮碳苷类成分及抗氧化作用进行比较,为扩大铁皮石斛的药用部位提供实验依据。 方法: 采用TLC和HPLC及与对照品对照,对铁皮石斛不同部位黄酮类成分种类和含量进行分析;以清除DPPH自由基能力对抗氧化活性进行比较。 结果: 铁皮石斛茎、叶和花中含有种类相同的黄酮二糖碳苷类成分,并采用对照品指认了共有的8个色谱峰;但各黄酮碳苷的含量有显著差异,叶和花中黄酮碳苷的含量明显高于...
DPPH Radical-Scavenging Activity and Polyphenol Content in Dried Fruits
dried fruits fresh fruits ascorbic acid
2009/6/18
The 1,1-diphenyl-2-picrylhydrazyl (DPPH) radical-scavenging activity and polyphenol content of 25 dried fruits were evaluated and compared with fresh fruits. The contribution of ascorbic acid to this ...
Evaluation of DPPH-Radical-Scavenging Activity and Antimutagenicity and Analysis of Anthocyanins in an Alcoholic Fermented Beverage Produced from Cooked or Raw Purple-Fleshed Sweet Potato（Ipomoea Batatas cv. Ayamurasaki）Roots
purple-fleshed sweet potato anthocyanin alcoholic beverage
2009/6/10
We investigated the 1,1-diphenyl-2-picrylhydrazyl (DPPH)-radical-scavenging activity and antimutagenicity of alcoholic fermented beverages produced from cooked or raw purple-fleshed sweet potato (Ipom...
Effects of Extracts from Tropical Seaweeds on DPPH Radicals and Caco-2 Cells Treated with Hydrogen Peroxide
Seaweed ethanol extract acetone extract
2009/5/20
Edible seaweeds were collected from Indonesia, a tropical country that does not show seasonal variations in temperature, to evaluate their health-related activities. Ethanol and acetone extracts were ...
Development and Validation of a Microplate-based β-carotene Bleaching Assay and Comparison of Antioxidant Activity (AOA) in Several Crops Measured by β-carotene Bleaching, DPPH and ORAC Assays
AOA β-carotene bleaching assay DPPH assay ORAC assay Trolox plate reader tocopherol
2010/3/5
The reproducibility and reliability of the micro-β-carotene-linoleic acid bleaching (BCB) assay have been improved, enabling comparison to the antioxidant activity (AOA) of extracts from eleven kinds ...