Food Microbiology Research Labs, Meiji Co., Ltd., Meiji Innovation Center, Hachiouji, Tokyo, Japan.
Division of Applied Biosciences, Graduate School of Agriculture, Kyoto University, Sakyo-ku, Kyoto, Japan.
Am J Clin Nutr. 2020 Apr 1;111(4):903-914. doi: 10.1093/ajcn/nqaa020.
Dietary supplementation with carotenoids can have beneficial health effects, but carotenoids are poorly absorbed.
We aimed to evaluate how milk fermented by lactic acid bacteria affects dietary carotenoid bioavailability in humans and rats and to investigate mechanisms by which active components in milk fermented by Lactobacilli enhance dietary carotenoid absorption.
Male rats (n = 8/group) were administered β-carotene or β-carotene + fermented milk. Rats (n = 6/group) were also pretreated with ezetimibe, a cholesterol absorption inhibitor, to investigate β-carotene transport mechanisms. In humans, 3 studies were conducted using a randomized crossover method. Subjects (n = 16/study) consumed a vegetable (carrot, tomato, or spinach) drink alone or with a fermented milk drink. Blood samples were collected at various time points after consumption.
In rats, the serum β-carotene area under the concentration-time curve (AUC) was significantly higher for the β-carotene + fermented milk than for β-carotene only. A significant correlation (r = 0.83, P < 0.001) between the exopolysaccharide (EPS) content of fermented milk and serum β-carotene AUC was observed. Ezetimibe treatment did not suppress elevations in serum β-carotene concentrations induced by fermented milk ingestion. In humans, the incremental area under the concentration-time curve (iAUC) for β-carotene in the plasma triacylglycerol-rich lipoprotein (TRL) fraction was significantly (1.8-fold, range: 0.6-3.9) higher when carrot + fermented milk was consumed compared with carrot drink alone. A significantly (6.5-fold, range: 0.04-7.7) higher iAUC for lycopene in the plasma TRL fraction was observed for subjects who consumed tomato + fermented milk compared with tomato drink alone. A significant increase in plasma lutein in all fractions was observed after consumption of spinach + fermented milk, but not with spinach drink alone.
Co-ingestion of β-carotene and fermented milk significantly increased dietary β-carotene bioavailability in humans and rats. EPSs could affect the physical properties of fermented milk to enhance dietary β-carotene absorption mediated by simple diffusion mechanisms. These findings may be relevant for methods to increase dietary carotenoid bioavailability.This trial was registered at umin.ac.jp/ctr as UMIN000034838, UMIN000034839, and UMIN000034840.
类胡萝卜素的膳食补充剂具有有益的健康效应，但类胡萝卜素的吸收率很低。
我们旨在评估乳酸菌发酵的牛奶如何影响人类和大鼠的膳食类胡萝卜素生物利用度，并研究乳杆菌发酵的牛奶中活性成分增强膳食类胡萝卜素吸收的机制。
雄性大鼠（n=8/组）给予β-胡萝卜素或β-胡萝卜素+发酵乳。大鼠（n=6/组）也用胆固醇吸收抑制剂依泽替米贝预处理，以研究β-胡萝卜素的转运机制。在人类中，使用随机交叉方法进行了 3 项研究。受试者（n=16/研究）单独或与发酵乳饮料一起饮用蔬菜（胡萝卜、番茄或菠菜）饮料。在消费后不同时间点采集血样。
在大鼠中，β-胡萝卜素+发酵乳的血清β-胡萝卜素浓度-时间曲线下面积（AUC）明显高于仅β-胡萝卜素。观察到发酵乳的胞外多糖（EPS）含量与血清β-胡萝卜素 AUC 之间存在显著相关性（r=0.83，P<0.001）。依泽替米贝处理并不能抑制发酵乳摄入引起的血清β-胡萝卜素浓度升高。在人类中，当与单独饮用胡萝卜饮料相比时，β-胡萝卜素在富含三酰甘油的脂蛋白（TRL）部分的血浆中的增量浓度-时间曲线下面积（iAUC）显著增加（1.8 倍，范围：0.6-3.9）。与单独饮用番茄饮料相比，当受试者饮用番茄+发酵乳时，番茄红素在血浆 TRL 部分的 iAUC 显著增加（6.5 倍，范围：0.04-7.7）。与单独饮用菠菜饮料相比，摄入菠菜+发酵乳后所有部分的血浆叶黄素均显著增加。
β-胡萝卜素和发酵乳的共同摄入显著增加了人类和大鼠膳食β-胡萝卜素的生物利用度。EPS 可能会影响发酵乳的物理性质，以增强通过简单扩散机制介导的膳食β-胡萝卜素吸收。这些发现可能与增加膳食类胡萝卜素生物利用度的方法有关。本试验在 umin.ac.jp/ctr 注册为 UMIN000034838、UMIN000034839 和 UMIN000034840。
