我国主要麦区小麦籽粒微量元素含量及营养评价

Evaluation on concentration and nutrition of micro-elements in wheat grains in major wheat production regions of China

小麦是重要的粮食作物,其微量元素含量高低直接影响人体健康。明确我国主要麦区小麦籽粒微量元素含量水平,对优化小麦微量元素营养品质,保障居民营养健康有重要意义。于2016—2020年,在我国17个小麦主产省区采集分析了1112份小麦及土壤样品,参考《中国营养学会人体微量元素摄入标准》和美国环境保护署健康风险评估方法,结合我国居民饮食特点,推荐了小麦籽粒微量元素适宜含量范围,并以此评价了我国小麦的微量元素营养状况。研究发现,我国小麦籽粒铁含量平均为43.8 mg kg^(-1), 72.9%样本低于铁的推荐量下限50 mg kg^(-1),所有样本铁含量均低于推荐量上限140 mg kg^(-1);籽粒锰含量平均为43.0 mg kg^(-1),仅4.1%样本低于推荐锰含量下限22 mg kg^(-1),但23.7%样本高于推荐上限值50 mg kg^(-1);籽粒铜含量平均为4.6 mg kg^(-1), 7.6%样本低于推荐量下限3 mg kg^(-1),所有样本铜含量均低于推荐量上限10 mg kg^(-1);籽粒锌含量平均为31.4 mg kg^(-1), 85.8%的样本低于推荐量下限40 mg kg^(-1),仅4.1%样本高于50mgkg^(-1)的推荐量上限;籽粒硼含量平均为1.2mgkg^(-1),低于推荐量下限0.8mgkg^(-1)的样本占29.2%,所有样本均低于推荐值上限10 mg kg^(-1);籽粒钼含量平均为0.5 mg kg^(-1), 18.8%的样本钼含量低于推荐量下限0.2 mg kg^(-1),仅有0.4%样本钼含量高于推荐值上限2 mg kg^(-1)。我国小麦籽粒微量元素含量也存在区域间变异,其中,铁、锌含量普遍偏低,部分地区硼、钼含量不足,而锰含量偏高,铜含量基本在推荐范围内。

Wheat is a kind of staple food crop,and an important source for carbohydrates and microelement for human health.Therefore,it is of great significance to clarify the micronutrient concentration and nutritional status of wheat grain in the major wheat production regions in China,for the purpose of optimizing wheat micronutrient management and maintaining human health.Totally,1112 wheat and soil samples were collected from 17 major wheat production provinces in China during 2016 to 2020.Microelement concentrations of the samples were determined and nutritional status was evaluated by comparison with the acceptable daily intake value(ADI)according to the human micronutrient intake standard of Chinese Nutrition Society and health risk assessment method of United States Environmental Protection Agency,as well as the dietary habit of Chinese residents.Results showed that the average grain iron(Fe)concentration of wheat in China was 43.8 mg kg^(-1) when 72.9%of the samples of Fe concentration was under the lower Fe limit of 50 mg kg^(-1),and all the samples were under the upper limit of 140 mg kg^(-1).The average grain manganese(Mn)concentration was 43.0 mg kg^(-1) when only 4.1%of samples were under the lower limit of 22 mg kg^(-1) and 23.7%of samples were above the upper limit of 50 mg kg^(-1).The average grain copper(Cu)concentration was 4.6 mg kg^(-1) when 7.6%of samples were under the lower limit of 3 mg kg^(-1) and no sample was above the upper limit of 10 mg kg^(-1).The average grain zinc(Zn)concentration was 31.4 mg kg^(-1) when 85.8%of samples were under the lower limit of 40 mg kg^(-1) and only 4.1%was above the upper limit of 50 mg kg^(-1).The average grain boron(B)concentration was 1.2 mg kg^(-1) when 29.2%of samples was under the lower limit of 0.8 mg kg^(-1) and no sample was above the upper limit of 10 mg kg^(-1).The average grain molybdenum(Mo)concentration was 0.5 mg kg^(-1) when 18.8%of samples were under the lower limit of 0.2 mg kg^(-1) and only 0.4%of samples was above the upper limit of 2 mg kg^(-1).There were regional variations in the contents of wheat grain micronutrient in major wheat production regions in China,among which the contents of Fe and Zn were generally low in most regions,and the contents of B and Mo were insufficient in some areas,while the content of Mn was high,and the content of Cu was basically in the recommended concentration ranges.