体外消化/Caco-2细胞模型评价铁生物强化玉米铁生物利用率

ASSESSMENT OF IRON BIOAVAILABILITY OF IRON BIOFORTIFIED MAIZE USING IN VITRO DIGESTION/CACO-2 CELL CULTURE MODEL

目的采用体外消化/Caco-2细胞模型评价3种生物强化玉米铁生物利用率,筛选出铁生物利用率高的玉米品种。方法将高铁玉米品种(中铁2号、中铁3号、中铁4号)和低铁玉米品种(正大818、正大619)磨粉,测定玉米粉中铁含量,经体外消化后进行Caco-2细胞吸收实验,以细胞单位质量蛋白质中铁蛋白含量作为铁生物利用率的指标,并计算单位质量玉米粉铁生物利用率。同时测定玉米粉总磷含量,以此反映玉米中植酸水平。结果中铁2号玉米粉中铁含量(33.25mg/kg)、铁生物利用率和单位质量玉米粉铁生物利用率最高,而总磷含量较低;铁生物利用率其次为中铁3号和正大818,正大619玉米粉最低。结论中铁2号玉米品种的铁含量与生物的利用率最高,可推荐为后续人群试验试用品种。

Objective To assess iron bioavailability of three iron-biofortified maizes using an in vitro digestion/ Caco-2 cell culture model. Method Three maize varieties rich in iron （Zhongtie 2, 3 and 4） and two maize varieties with lower content of iron （Zhengda 818 and 619） were pulverized, and the content of iron and phosphorus in each maize variety was measured. After digestion the iron bioavailability per g food was determined by using Caco-2 cell ferritin formation per mg cell protein as indicator. Results The iron content （33.250 mg/kg）, iron bioavailability and the iron bioavailability per g food of Zhongtie 2 maize was the highest among all varieties, but its phosphorus content was lower. The maize varieties with the next higher iron bioavailability were Zhongtie 3 and Zhengda 818, and the lowest was Zhengda 619. Conclusion Zhongtie 2 maize contained the hightest content and bioavailability of iron,so it was optimal to use for the following human trials.