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11.
M P Vaquero M Veldhuizen W van Dokkum C J A van den Hamer G Schaafsma 《Journal of the science of food and agriculture》1994,64(4):475-481
The influence of drinking tea on copper bioavailability is unclear, particularly when tea is consumed with food. A breakfast meal containing white bread, margarine, strawberry jam, cheese and tea, with or without milk, was digested in; vitro and the dialysis of copper investigated. Reference breakfasts were prepared with water and water with milk. Copper dialysability (percentage of copper dialysed) was markedly increased by tea. The influence of adding milk to tea was not significant. A second study was carried out in rats using the breakfasts containing tea and water. They were spiked with 64Cu and given orally to the animals in a single dose. Whole-body 64Cu retention was measured over a 4-day period after administration. In order to determine the true absorption of 64Cu a control group of rats received the dose intraperitioneally. The results in vivo indicate a tendency to higher absorption and retention of 64Cu with tea. Liver 64Cu retention was significantly elevated by tea. Therefore, the presence of tea in a breakfast meal favours the formation of soluble low-molecular-weight ligands which can be absorbed and retained by rats. The concomitant increase in liver copper retetition may be associated with higher bioavailability and/or lower copper mobilisation. 相似文献
12.
Nuchanart Suealek Thipaporn Tharavanij Robert M. Hackman Carl L. Keen Roberta R. Holt Benjapun Burawat Ammara Chaikan Rattana Tiengtip Panadda Rojpibulstit 《European Journal of Lipid Science and Technology》2021,123(2):2000126
The potential cardiovascular benefit of virgin olive oil (VOO) is widely recognized. However, the use of VOO at very high cooking temperatures makes these oils poorly suited for many Asian dishes. The use of tea seed oil (TSO) is increasing in Thailand, with TSO having a higher smoke point than VOO. The current study examines the effects of daily TSO intake in healthy adults. In a randomized, single-blind crossover design, 12 men consumed for 3 weeks 40 g day−1 of food prepared with either TSO or VOO as a cooking oil. Plasma lipids, thiobarbituric acid reactive substances (TBARS), and oxidant defense enzyme activities are measured before and after each 3-week intervention period. Gas chromatography analysis of TSO and VOO demonstrates that both oils are equally high in monounsaturated fatty acid. The dietary incorporation of TSO and VOO for three weeks reduces low-density lipoprotein cholesterol (LDL-C) concentrations by 15% and 13%, respectively; with total cholesterol (TC) levels lowered by 10% in both groups. No significant changes in TBARS or antioxidant enzyme activity is observed. These results support the concept that Thai TSO can be utilized as a suitable and healthy alternative oil for high-temperature cooking in many Thai and Asian diets. Practical Applications: Tea seed oil from Camellia oleifera grown in Thailand has been recently reported to favorably lower lipid profiles in hamsters fed a high-fat diet in a manner similar to feeding refined olive oil or grapeseed oil. A pilot crossover trial is conducted to compare the effects of three weeks of daily intake of either TSO or VOO in healthy human adults. Consumption of both oils produced significant reductions in TC and LDL-C. Thai TSO leads to favorable lipid profiles and is a reasonable choice for many Thai and Asian food recipes. 相似文献
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欧盟在对硫丹进行风险评估的基础上,于2005年5月3日和6月2日,先后发布SPS和TBT通报,撤销硫丹作为植物保护产品登记。按照欧盟相关指令的要求,硫丹在茶叶中的MRLs由30mg/kg调整为0.01mg/kg。硫丹是目前我国茶叶生产中的农药推广品种,而且欧盟是我国重要的茶叶出口市场,欧盟的此项规定对我国茶叶出口有一定的影响,应当采取措施积极应对。 相似文献
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分子修饰法制备油溶性茶多酚及其抗氧化性能的研究 总被引:4,自引:0,他引:4
采用分子修饰法制备了豆油脂肪酸酐修饰的茶多酚,通过红外光谱对分子修饰的茶多酚进行了结构表征。将修饰后的茶多酚作为油脂的抗氧化剂,添加到豆油中,考察其溶解性及抗氧化性能。结果表明,有机基团修饰的茶多酚具有优良的分散性,可提高豆油的抗氧化性能。在相同浓度时,豆油脂肪酸酐修饰的茶多酚抗氧化活性优于茶多酚和BHT。 相似文献
16.
超声波提取-吸附分离-气相色谱法测定茶叶中农药残留 总被引:1,自引:0,他引:1
将超声提取-吸附分离的预处理技术用于气相色谱法检测茶叶中的农药残留。对超声波提取条件和吸附分离柱(自制)的结构进行了优化。建立了茶叶中有机磷类和菊酯类农药残留的气相色谱法定量测定的方法。进行了3个质量分数的标准添加,甲胺磷、乐果、联苯菊酯、氯氟氰菊酯、溴氰菊酯的回收率相应为75%~95%、87%~110%、89%-102%、88%-105%、80%-93%,相对标准偏差为2.6%.4.8%,检出限为0.005-0.02mg/kg。该方法速度快、灵敏度高、重现性好。 相似文献
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对油茶果的深度开发作了较为详尽的研究:在尽可能提高茶油产率的同时,对榨取茶油以后的粕饼或渣,籽仁以及精制茶油后的脚料等物进行再提取或回收,从中又可得到能增值的精细化学的绿色产品——茶皂素和脂肪酸。 相似文献
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马旭 《齐齐哈尔轻工业学院学报》2009,(4):92-93
建立了茶饮料中糖精钠的荧光分光光度测定方法。样品前处理采用盐酸酸化,加入氯化钠,乙醚萃取后再用2 g/L碳酸钠溶液洗涤乙醚萃取层,加热除去乙醚定容后用荧光光度计测定。测试条件为:激发波长265 nm,发射波长475 nm。方法检测限为2 mg/kg,线性范围在2~60 mg/kg之间,变异系数为1.97%,回收率96.8%。 相似文献