从农艺生物强化小麦中吸收的锌与收获后强化小麦相似，是人类生物可利用锌的重要来源。

Zinc Absorption From Agronomically Biofortified Wheat Is Similar to Post-Harvest Fortified Wheat and Is a Substantial Source of Bioavailable Zinc in Humans.

机构信息

Laboratory of Human Nutrition, Institute of Food, Nutrition and Health, ETH Zurich, Zurich, Switzerland.

Faculty of Engineering and Natural Sciences, Sabanci Universitesi, Istanbul, Turkey.

出版信息

J Nutr. 2019 May 1;149(5):840-846. doi: 10.1093/jn/nxy328.

DOI:10.1093/jn/nxy328

PMID:31004128

Abstract

BACKGROUND

Limited data exist on human zinc absorption from wheat biofortified via foliar (FBW) or root (hydroponically fortified wheat, HBW) zinc application. Stable isotope labels added at point of consumption (extrinsic labeling) might not reflect absorption from native zinc obtained by intrinsic labeling.

OBJECTIVES

We measured fractional and total zinc absorption (FAZ, TAZ) in FBW and HBW wheat, compared with control wheat (CW) and fortified wheat (FW). The effect of labeling method was assessed in HBW (study 1), and the effect of milling extraction rate (EXR, 80% and 100%) in FBW (studies 2 and 3).

METHODS

Generally healthy adults (n = 71, age: 18-45 y, body mass index: 18.5-25 kg/m2) were allocated to 1 of the studies, in which they served as their own controls. In study 1, men and women consumed wheat porridges colabeled intrinsically and extrinsically with 67Zn and 70Zn. In studies 2 and 3, women consumed wheat flatbreads (chapatis) labeled extrinsically. Zinc absorption was measured with the oral to intravenous tracer ratio method with a 4-wk wash-out period between meals. Data were analyzed with linear mixed models.

RESULTS

In study 1 there were no differences in zinc absorption from extrinsic versus intrinsic labels in either FW or HBW. Similarly, FAZ and TAZ from FW and HBW did not differ. TAZ was 70-76% higher in FW and HBW compared with CW (P < 0.01). In studies 2 and 3, TAZ from FW and FBW did not differ but was 20-48% higher compared with CW (P < 0.001). Extraction rate had no effect on TAZ.

CONCLUSIONS

Colabeling demonstrates that extrinsic zinc isotopic labels can be used to accurately quantify zinc absorption from wheat in humans. Biofortification through foliar zinc application, root zinc application, or fortification provides higher TAZ compared with unfortified wheat. In biofortified wheat, extraction rate (100-80%) has a limited impact on total zinc absorption. These studies were registered on clinicaltrials.gov (NCT01775319).

摘要

背景

关于通过叶面（FBW）或根部（水培强化小麦，HBW）锌应用使小麦生物强化后人体对锌的吸收情况，目前仅有有限的数据。在消费点添加的稳定同位素标记（外源性标记）可能无法反映通过内源性标记获得的天然锌的吸收情况。

目的

我们测量了 FBW 和 HBW 小麦中的部分和总锌吸收（FAZ、TAZ），并与对照小麦（CW）和强化小麦（FW）进行了比较。在 HBW 中评估了标记方法的影响（研究 1），并在 FBW 中评估了制粉提取率（EXR，80%和 100%）的影响（研究 2 和 3）。

方法

一般健康成年人（n=71，年龄：18-45 岁，体重指数：18.5-25kg/m2）被分配到一项研究中，在该研究中他们作为自身对照。在研究 1 中，男性和女性食用同时用 67Zn 和 70Zn 内源性和外源性标记的小麦粥。在研究 2 和 3 中，女性食用外源性标记的小麦薄饼（chapati）。用口服至静脉示踪剂比值法测量锌吸收，每餐后有 4 周的洗脱期。使用线性混合模型进行数据分析。

结果

在研究 1 中，FW 和 HBW 中外源性和内源性标记的锌吸收没有差异。同样，FW 和 HBW 的 FAZ 和 TAZ 也没有差异。与 CW 相比，FW 和 HBW 的 TAZ 高 70-76%（P<0.01）。在研究 2 和 3 中，FW 和 FBW 的 TAZ 没有差异，但与 CW 相比高 20-48%（P<0.001）。提取率对 TAZ 没有影响。