Staple food crops from Brazilian Biofortification Program have high protein quality and hypoglycemic action in Wistar rats

Abstract Biofortified staple food crops have become an effective tool by which to address micronutrient deficiencies in many at-risk populations. The effect of these food crops on the micronutrient status has been evaluated, however there is no studies investigating their protein quality, neither by themselves or in a food combination. Thus, this study investigated the effect of combinations of beans and rice, target for biofortification, with high carotenoids content crops (sweet potato and pumpkin) on protein quality, intestinal function and glycemia. Eight groups were evaluated (n=6): 1) rice + Caupi bean (RCB); 2) rice + Pontal bean (RPB); 3) rice + Caupi bean + pumpkin (RCBP); 4) rice + Pontal bean + pumpkin (RPBP); 5) rice + Caupi bean + sweet potato (RCBS); 6) rice + Pontal bean + sweet potato (RPBS); 7) casein (positive control); and 8) nitrogen free (negative control). Tested groups showed high protein quality, and groups containing Caupi bean showed higher true digestibility. Groups containing Pontal bean had a greater reduction of blood glucose compared to casein. Tested groups showed higher fecal excretion of lipids. Combination of food target for biofortification showed high protein quality, and the combinations containing Pontal beans showed hypoglycemic effect.

摘要：生物强化主食作物（biofortified staple food crops）已成为解决众多高危人群微量营养素缺乏问题的有效工具。现有研究已评估此类粮食作物对机体微量营养素状态的影响，但尚无研究探讨其自身或与食物搭配时的蛋白质品质。
因此，本研究针对作为生物强化目标的菜豆与稻米组合，搭配高类胡萝卜素含量作物（甘薯与南瓜），探究其对蛋白质品质、肠道功能及血糖水平的影响。
本研究共设置8个实验组（每组n=6）：1）稻米+豇豆（RCB）；2）稻米+蓬塔尔豆（RPB）；3）稻米+豇豆+南瓜（RCBP）；4）稻米+蓬塔尔豆+南瓜（RPBP）；5）稻米+豇豆+甘薯（RCBS）；6）稻米+蓬塔尔豆+甘薯（RPBS）；7）酪蛋白（阳性对照）；8）无氮组（阴性对照）。
实验结果显示，各受试组均表现出较高的蛋白质品质，其中添加豇豆的组别真消化率更高；添加蓬塔尔豆的组别血糖降幅显著高于酪蛋白组；受试各组粪便脂质排泄量均有所升高。
综上，作为生物强化目标的食物组合具有优异的蛋白质品质，且添加蓬塔尔豆的组合可展现降血糖作用。