Institute of Food Research, Norwich Research Park, Norwich, UK.
Mol Nutr Food Res. 2013 Jul;57(7):1209-17. doi: 10.1002/mnfr.201200663. Epub 2013 Apr 23.
Flavanol-rich foods are known to exert beneficial effects on cardiovascular health. The biological effects depend on bioavailability of flavanols which may be influenced by food matrix and dose ingested. We compared the bioavailability and dose-response of epicatechin from whole apple and an epicatechin-rich extract, and the effects on plasma and urinary nitric oxide (NO) metabolites.
In a randomized, placebo-controlled, crossover trial, subjects consumed drinks containing 70 and 140 mg epicatechin from an apple extract and an apple puree containing 70 mg epicatechin. Blood and urine samples were collected for 24 h post ingestion. Maximum plasma concentration, AUC(0-24 h) , absorption and urinary excretion were all significantly higher after ingestion of both epicatechin drinks compared with apple puree (p < 0.05). Time to maximum plasma concentration was significantly later for the puree compared with the drinks (p < 0.01). Epicatechin bioavailability was >2-fold higher after ingestion of the 140 mg epicatechin drink compared to the 70 mg epicatechin drink (p < 0.05). Excretion of NO metabolites was higher for all test products compared with placebo, which was significant for the high dose drink (p = 0.016).
Oral bioavailability of apple epicatechin increases at higher doses, is reduced by whole apple matrix and has the potential to increase NO bioavailability.
富含黄烷醇的食物已知对心血管健康有益。生物效应取决于黄烷醇的生物利用度，而生物利用度可能受食物基质和摄入剂量的影响。我们比较了整苹果和富含儿茶素的提取物中儿茶素的生物利用度和剂量反应，以及对血浆和尿中一氧化氮（NO）代谢物的影响。
在一项随机、安慰剂对照、交叉试验中，受试者分别饮用含有 70 毫克和 140 毫克儿茶素的苹果提取物饮料和含有 70 毫克儿茶素的苹果纯饮。摄入后 24 小时内采集血液和尿液样本。与苹果纯饮相比，摄入两种儿茶素饮料后，血浆中儿茶素的最大浓度、AUC（0-24 h）、吸收和尿排泄均显著升高（p < 0.05）。与饮料相比，纯饮时达到血浆中儿茶素最大浓度的时间明显延迟（p < 0.01）。与摄入 70 毫克儿茶素饮料相比，摄入 140 毫克儿茶素饮料后儿茶素的生物利用度提高了 2 倍以上（p < 0.05）。与安慰剂相比，所有测试产品的 NO 代谢物排泄均升高，高剂量饮料组差异有统计学意义（p = 0.016）。
口服苹果儿茶素的生物利用度随剂量增加而增加，被完整的苹果基质所降低，并有增加 NO 生物利用度的潜力。
