豆渣复配粉对老龄大鼠蛋白质消化动力的影响

Effects of soybean residue compound powder on protein digestion dynamic in aging mice

我国老龄化人口逐年递增,老年人消化机能减退,进而影响健康状况.以老龄大鼠为动物模型来研究富含膳食纤维的豆渣复配粉对其肠道消化蛋白质功能的影响,进而对豆渣膳食纤维在老龄人中的应用提供理论依据和实践参考.采用挤压膨化的方法制备了大豆渣复配粉,复配粉中豆渣与淀粉的比例为3∶7,复配粉可溶性膳食纤维的含量平均值为15.47%.大鼠试验选用15月龄大鼠15只,随机分为3组,分别接受3个处理:标准日粮组(AIN)、鱼肉蛋白组(FP)、鱼肉蛋白+豆渣复配粉组(FPS,0.3g/kg).每组5只大鼠,大鼠单笼饲养,组内设5个重复.结果表明:FPS组大鼠蛋白质整肠道消化率较其他2组显著提高(P<0.05),FP组显著降低了蛋白质消化率(P<0.05),FP组和FPS组大鼠肠道胰蛋白酶和肠肽酶都显著高于对照组(P<0.05),FPS组大鼠肝脏氨肽酶(APN),小肽转移酶(PepT1)和谷氨酸脱氢酶(GDH)mRNA表达量分别显著高于其他2组(P<0.05).以上研究结果说明豆渣复配粉有利于提高老龄大鼠对日粮蛋白的消化率,改善肠道相关蛋白消化酶的基因表达.

The number of elderly person is annually increasing in China.The digestive function declines in elderly people,which in turn affects their health status.The aim of this study is to investigate the effects of soybean residue compound powder with high dietary fiber on gut protein digestion using aging mice as donate animal model,and further more provide theoretical base and practical recommendations for the soybean residue compound powder application in elderly people.This experiment adopted method of extrusion and expansion to prepare soybean residue compound,.in which the ratio of soybean residue to starch is 30:70 and the average soluble dietary fiber content reached 15.47%.15-month mice were selected and randomly assigned to 3 treatments i.e.standard diet group(AIN),fish protein group(FP)and fish protein plus soybean residue(FPS,0.3 g/kg).Results indicate that the whole digestive tract digestibility of protein in FPS group was significantly higher than the other 2 groups(P<0.05),and FP dietary protein digestibility is lower than control group(P<0.05).The proteases trypsin and pepsin involved in protein digestion in FP group and FPS group are higher than control group respectively(P<0.05).The gene mRNA expressions of APN,PEPT1 and GDH involved in protein digestion in liver of mice fed soybean residue compound powder were higher than the other 2 groups(P<0.05).The above mentioned results show that soybean residue compound powder favored protein digestion in aging mice and improved the relative gene expression of protein digestion.