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茶多酚体内外抗流感病毒作用研究 总被引：5，自引：0，他引：5
研究了没食子儿茶素(Gallocatechin, GC)、表儿茶素(Epicatechin, EC)、表没食子儿茶素(Epigallocatechin, EGC)、表儿茶素没食子酸酯(Epicatechin gallate, ECG)、表没食子儿茶素没食子酸酯(Epigallocatechin gallate, EGCG)、原儿茶醛(Protocatechuic aldehyde, PAD)、原儿茶酸(Protocatechuic acid, PA)共7种茶多酚类物质在MDCK细胞中的抑制流感病毒活性。结果表明,EGCG和ECG具有显著的抑制病毒作用,对感染H5N1、H1N1和H9N2 3种亚型流感病毒的MDCK细胞50%保护率浓度(EC50)分别在0.04~0.11 mmol/L和0.05~0.07 mmol/L范围,其保护效果均优于阳性对照药利巴韦林（EC50：0.41~0.53 mmol/L）。7种茶多酚类物质对流感病毒神经氨酸酶（NA）均有不同程度的抑制作用,EGCG和ECG对H5N1、H1N1和H9N2 3种亚型流感病毒NA活性抑制浓度（IC50）分别在0.03~0.14 mmol/L和0.34~0.69 mmol/L范围。茶多酚对NA的抑制活性大小与其细胞中对病毒的抑制作用基本一致,表明对NA的抑制可能是其抗流感病毒机制。本文还研究了茶多酚含量为85%的苦茶(C. assamica var. Kucha)提取物对感染流感病毒小鼠的肺炎抑制效果,结果显示,1 000 mg/(kg·d)苦茶提取物对感染H9N2亚型流感病毒BALB/c鼠肺炎有显著抑制作用(P﹤0.05),肺指数抑制率达37%。 相似文献
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李子果肉单宁结构及其抗氧化能力的研究 总被引：5，自引：2，他引：3
对李子果肉的总酚含量与可溶性缩合单宁含量进行了测定,并利用基质辅助激光解吸附离子化飞行时间质谱(MALDI-TOFMS)联合核磁共振(NMR)技术详细研究了李子果肉单宁的类型、聚合度及平均分子质量.同时用二苯基苦基肼自由基(DPPH·)法研究了李子果肉单宁的抗氧化活性.结果表明:李子果肉中总酚质量分数为8.29%±1.30%,可溶性缩合单宁质量分数为1.43%±0.93%;构成该单宁的黄烷-3-醇结构单元主要是表儿茶酚,在化学结构上属于原花青定类型,且大部分聚合物的结构单元之间存在A型和B型2种连接方式,平均聚合度为5.3,平均分子质量为1583.7u;李子果肉单宁具有较高的自由基清除能力,其半数有效浓度(EC50)为57.98mg/L. 相似文献
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杨梅不同部位单宁含量与结构研究 总被引：1，自引：0，他引：1
对杨梅的叶、枝和树皮的总酚含量与可溶缩合单宁含量进行了测定,并利用基质辅助激光解吸附飞行时间质谱(MALDI-TOFMS)详细研究了不同部位中缩合单宁的类型、聚合度及聚合物的分布情况。结果表明:树皮的总酚含量最高(43.56%),叶次之(34.69%),枝最低(18.53%);树叶的可溶缩合单宁含量最高(25.67%),皮次之(17.93%),枝最低(8.01%);3组分的缩合单宁都以(表)棓儿茶素-3-O-棓酸酯(EGCG/GCG)为基本结构单元的原翠雀定,且大部分聚合物的结构单元之间存在A型和B型两种连接方式,但其中叶和枝缩合单宁的聚合度要大于树皮。 相似文献
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Praveen Guleria Vineet Kumar 《The Journal of Horticultural Science and Biotechnology》2017,92(4):335-348
The phenylpropanoid pathway is an important diversified secondary or specialised metabolic route. It gives rise to various metabolites that regulate plant growth, metabolism, and plant–environment interactions. Genetic manipulations of the phenylpropanoid pathway have even improved the agronomy and nutritional status of plants. Irrespective of such explorations, this pathway has not been vastly investigated in legumes to date. Mungbean (Vigna radiata L.) is the most commonly produced leguminous crop of Asia. It is an important source of plant protein that has been recommended over several animal proteins. Dry mungbean seeds as well as sprouts are a rich source of phenylpropanoids. Mungbean sprouts possess increased protein bioavailability and have higher antioxidant potential than dry seeds. The polyphenolic derivatives of the phenylpropanoid pathway in mungbean are responsible for their antioxidant potential. Hence, from this perspective, the present article reviews the agronomic and biochemical traits of mungbean with an emphasis on the phenylpropanoid pathway and derived metabolites. 相似文献
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不同果桑品种桑椹成熟过程中非花青素酚类物质的含量变化 总被引：3，自引：1，他引：2
采用高效液相色谱(HPLC)法测定了3个果桑品种大10、选27、苗66的桑椹成熟过程中15种非花青素酚类物质及总酚的含量变化与差异。以ZORBAX SB-C18色谱柱(4.6 mm×250 mm,5μm)和流动相A(乙腈)、B(0.4%冰醋酸)进行梯度洗脱,可以较好地分离测定桑椹中的非花青素酚类物质。在3个品种的桑椹成熟过程中,15种非花青素酚类物质的含量变化不尽相同,不同的非花青素酚类物质在同一品种桑椹成熟过程中的含量变化不完全相同,同一种非花青素酚类物质在不同品种桑椹成熟过程中的含量变化也不完全相同。3个品种的成熟桑椹中,15种非花青素酚类物质含量均依次为儿茶素>芦丁>金丝桃苷>安息香酸>绿原酸>龙胆酸>水杨酸>阿魏酸>香草酸>槲皮素>表儿茶素>没食子酸>丁香酸>咖啡酸>白藜芦醇;桑椹多酚物质的总含量在成熟过程中逐渐增加,其含量为选27>大10>苗66。 相似文献
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为筛选出酚类物质含量高且具有较高抗氧化活性的酿酒葡萄种质资源,分别以4个红色和4个白色酿酒葡萄成熟果实为材料,比色法测定果皮、果肉和种子中的总酚、单宁、总类黄酮、原花色素和黄烷醇含量,以总还原力、DPPH自由基、ABTS+·自由基清除能力评价其抗氧化能力。结果表明,各品种果皮、果肉和种子中各酚类物质含量具有明显差异,但均以果肉中含量最低。红色品种果皮和种子中酚类物质含量均高于白色品种（‘小白玫瑰455’除外）,其中以‘黑比诺667’中总酚、单宁和总类黄酮含量最高,而果皮原花色素和黄烷醇含量以‘蛇龙珠’最高,种子原花色素含量以‘法国蓝’最高。白色品种中,‘小芒森’果皮各酚类物质含量均最低,而种子中含量以‘小白玫瑰455’最高。各葡萄品种果皮和种子的抗氧化能力和其总酚、单宁、总类黄酮、原花色素和黄烷醇含量之间均为显著正相关,相关系数在0.8383~0.9983,而果肉中的相关性较弱。选用的3种方法对葡萄果实抗氧化活性进行评价时,测定结果在不同方法间存在协同性与差异性。 相似文献
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P. F. Surai 《Journal of animal physiology and animal nutrition》2014,98(1):19-31
Animal feed provides a range of antioxidants that help the body building an integrated antioxidant system responsible for a prevention of damaging effects of free radicals and products of their metabolism. Vitamin E is considered to be the main chain‐breaking antioxidant located in the membranes and effectively protecting them against lipid peroxidation. Recently, various polyphenol compounds, especially flavonoids, have received substantial attention because of their antioxidant activities in various in vitro systems. However, it was shown that flavonoid compounds are poorly absorbed in the gut and their concentrations in target tissues are too low to perform an effective antioxidant defences. The aim of the present paper is to review existing evidence about possible roles of various plant extracts provided with the diet in animal/poultry nutrition with a specific emphasis to their antioxidant activities. 相似文献
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Ricardo Bressani Eloisa Hernandez J. Edgar Braham 《Plant foods for human nutrition (Dordrecht, Netherlands)》1988,38(1):5-21
The purpose of this study was to determine the effect of bean polyphenolics on bean protein digestibility in humans. Steam pressure cooking decreased tannic acid in beans by: 38.2 (white), 23.9 (red), 38.5 (white:black mixture, 50:50), 20.5 (Ipala black) and 44.4% (Jalpatagua black). The reduction in catechin was: 57.5, 97.6, 83.0, 78.7 and 88.4%, respectively. The content of tannic acid in dried cooked beans was: 284.9 in white, 834.5 in red, 620.2 in the white:black mixture, 1,021 in Ipala black and 1,009 mg/100 g in the Jalpatagua black bean. These percentages correlate significantly with fecal nitrogen (r=0.29, p<0.05). Catechin of the dried cooked beans was 7.5 in white, 27.4 in red, 25.4 in the white:black mixture (50:50), and 60.1 and 55.5 mg/100 g in each of the black cultivars, and correlated significantly with fecal nitrogen (r=0.34, p<0.01), absorbed nitrogen (r=–0.37, p<0.01) and protein digestibility (r=–0.35, p<0.01). It was concluded that one of the factors that reduces bean protein digestibility is the polyphenlic compound. 相似文献
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