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101.
Nadine Müller Sabine Ellinger Birgit Alteheld Gudrun Ulrich‐Merzenich Heiner K. Berthold Hans Vetter Peter Stehle 《Molecular nutrition & food research》2010,54(11):1636-1645
White tea (WT) is rich in flavan‐3‐ols as green tea (GT) and might provide health protective effects due to the strong antioxidant properties of flavan‐3‐ols. Since intervention studies with WT are lacking, we evaluated the effects of WT consumption on antioxidant status, antioxidant capacity and biomarkers of oxidative stress compared to water and GT. After an overnight fast, 70 healthy non‐smokers were randomized to consume 600 mL of WT, GT or water (control). Plasma (epi‐)catechin and epi(gallo)catechingallate, antioxidant capacity (Folin assay, trolox equivalent antioxidant capacity test), 8‐iso‐prostaglandin F2α, ascorbic acid and uric acid were determined before and several times within 8 h after consumption. DNA strand breaks were measured in vivo and ex vivo (H2O2 stimulation) in leukocytes. Plasma flavan‐3‐ols significantly increased after WT and GT ingestion. Trolox equivalent antioxidant capacity was lower after 5 h in controls versus WT (p=0.031) and GT (p=0.005). Folin‐Ciocalteu reducing capacity, ascorbic and uric acid as well as markers of oxidative stress (8‐iso‐prostaglandin‐F2α, DNA strand breaks) were not affected by the beverages. A short‐term increase of catechins does not change plasma antioxidant capacity in healthy subjects. Conclusions with respect to health protective effects of WT and GT on the basis of these biomarkers can, thus, not be drawn. 相似文献
102.
湖北长阳绿茶挥发油成分的GC/MS分析 总被引:5,自引:0,他引:5
用气相色谱/质谱联用法分析了湖北长阳绿茶挥发油的化学成分,分离出93个组分,鉴定了84个化合物,挥发油中含芳樟醇、香叶醇、香茅醇等多种香气成分。 相似文献
103.
用气相色谱—质谱法分析了岭头单枞乌龙茶不同湿度做青香气组分的变化 .结果表明 ,做青湿度是影响乌龙茶香气的重要因素 .高湿 ( 90 % )、低湿 ( 70 % )做青芳香物质种类少 ,精油总量低 ,特征组分含量低 ;中湿 ( 80 % )做青芳香物质种类多 ,精油总量高 ,特征组分含量高 . 相似文献
104.
两种大豆皂甙提取方法的比较 总被引:3,自引:0,他引:3
考察了大豆皂甙的有机溶剂提取方法,建立了吸附层析提取大豆皂甙的方法。通过高效液相色谱,紫外光谱及薄层层析分析,对两种方法民提取的大豆皂甙进行了比较。 相似文献
105.
过山 《湖南工业大学学报》2002,16(2)
茶叶有着忌光、忌潮的物理特性 ,在包装材料的使用方面 ,我们必须把握合适的材料 ;茶叶还具有浓郁优雅的文化特性 ,在包装设计上可以通过图形、文字及色彩等体现文化的意蕴 ;茶叶还具有丰富多彩的品种特性及千姿百态的地域特性 ,在包装设计中应有针对性地进行设计。据此探讨茶叶包装设计的创新思路 相似文献
106.
In addition to the well reported beneficial effects of horse chestnut (Aesculus hippocastanum) extracts on venous insufficiency and associated conditions, such preparations also have many potential positive pharmacological effects on the skin. Extracts from this species, and in particular, those based on horse chestnut seeds, contain saponins, known collectively as 'aescin', which have a gentle soapy feel, and are potent anti-inflammatory compounds. Saponins, such as escin, also reduce capillary fragility, and therefore help to prevent leakage of fluids into surrounding tissues, which can cause swelling. An extract of horse chestnut has recently been shown to have one of the highest 'active-oxygen' scavenging abilities of 65 different plant extracts tested. Such extracts are more powerful anti-oxidants than vitamin E, and also exhibit potent cell-protective effects, which are linked to the well-known anti-ageing properties of anti-oxidants. The extract is also rich in a number of flavonoids, such as derivatives of quercetin and kaempferol. Flavonoids also have protective effects on blood vessels, and are well-known, powerful anti-oxidants. 相似文献
107.
以HP-INNOWax(30m×0.25mm×0.25μm)毛细管柱为分离柱,气相色谱/质谱(GC/MS)分析中国乌龙茶“白芽奇兰”的香气成分,结果表明,“白芽奇兰”茶的香气主成分为:氧化里哪醇,α-萜品醇、里哪醇、己酸、苯甲醇、苯己醇、苯乙腈、巴他酸-3-乙烯酯、橙花醇、橙花叔醇、苏合香烯及4-王酮等。 相似文献
108.
Effect of sarsaponin on ruminal fermentation with particular reference to methane production in vitro 总被引:6,自引:0,他引:6
This experiment was designed to investigate the effects of different concentrations (0, 1.2, 1.8, 2.4, and 3.2 g/L) of sarsaponin on ruminal microbial methane production using the substrates soluble potato starch, cornstarch, or hay plus concentrate (1.5:1). Ruminal fluid was collected from a dairy cow, mixed with phosphate buffer (1:2) and incubated (30 ml) anaerobically at 38 degrees C for 6 and 24 h with or without sarsaponin. Excluding the lower level of sarsaponin, pH of the medium was slightly decreased. Ammonia-N concentration and numbers of protozoa were decreased in a dose-dependent manner. Total volatile fatty acids and total gas production were increased. Molar proportion of acetate was decreased and propionate was increased with a corresponding decrease in acetate:propionate ratio. Hydrogen production was decreased. As the concentration of sarsaponin increased from 1.2 to 3.2 g/L, fermentation of soluble potato starch, cornstarch, or hay plus concentrate decreased methane production from 20 to 60% (6 h) and 17 to 50% (24 h), 21 to 58% (6 h) and 18 to 52% (24 h), and 23 to 53% (6 h) and 15 to 44% (24 h), respectively. Excluding the lower dose concentration (1.2 g/L) of sarsaponin, in vitro disappearance of dry matter of hay plus concentrate was decreased after 24 h. In conclusion, these results show that sarsaponin stimulated the mixed ruminal microorganism fermentation as well as to inhibit methane production in vitro. 相似文献
109.
本文建立了乌龙茶茶汤中的有机磷、有机氯和拟除虫菊酯类农药的提取、净化和气相色谱检测的方法。试样茶汤用乙酸乙酯萃取,其中有机氯和菊酯类农药采用LC-FlorisilSPE小柱净化,采用GC-FPD和GC-ECD检测。该方法对敌敌畏、甲胺磷、乐果、久效磷、马拉硫磷、毒死蜱、水胺硫磷、三唑磷8种有机磷农药的回收率在63.1%~92.0%,变异系数在2.5%~9.8%之间;对六六六、硫丹、DDT、甲氰菊酯、功夫菊酯、氯氰菊酯、氰戊菊酯、溴氰菊酯8种有机氯、菊酯类农药的回收率在72.7%~105.2%,变异系数在1.5%~12.7%之间。 相似文献
110.
谈国兴 《扬州大学烹饪学报》2007,24(1):20-23
茶肴具有色泽鲜艳、提神保健、茶香溢口、增进风味的特点,既可美化菜肴,提高食欲,又能防治某些疾病,是一种值得推广的营养保健菜式。研究茶肴历史、保健功效和烹调技法,必将对茶肴的推广和运用起到积极的作用。 相似文献