Friedrich M, Schadereit R, Uhlig J, Proll J, Noack R, Bock H D
Nahrung. 1978;22(2):237-50.
The authors investigated the nitrogen content of different fractions and in particular the aminoacid composition of the trichloroacetic acid (TCA)-precipitable and TCA-soluble peptides in the distal small intestine of rats which had been fed experimental diets (nitrogen-free or containing casein, wheat gluten or molasses yeast as a protein carrier). Parallel with this, they determined in growing rats the nitrogen and amino-acid digestibility of molasses yeast and wheat gluten according to the technique of faecal analysis, and studied the amino-acid composition of the faecal protein. Independently of the dietary protein fed, the peptide fractions of the content of the intestine showed an amino-acid composition that was largely similar to that found in case of nitrogen-free diet. The amino-acid composition of the faecal protein is, independently of the dietary protein given, relatively constant and corresponds approximately to the intestinal loss protein. There is agreement between the amino-acid composition of the TCA-precipitable peptide fractions and those of the corresponding faecal proteins. These components seem to be of endogenous origin.
作者研究了不同组分的氮含量，特别是喂食实验性日粮（无氮日粮或含酪蛋白、小麦麸质或糖蜜酵母作为蛋白质载体的日粮）的大鼠远端小肠中三氯乙酸（TCA）可沉淀和TCA可溶肽的氨基酸组成。与此同时，他们采用粪便分析法测定了生长大鼠中糖蜜酵母和小麦麸质的氮和氨基酸消化率，并研究了粪便蛋白质的氨基酸组成。无论喂食何种日粮蛋白质，肠内容物的肽组分显示出的氨基酸组成与无氮日粮情况下发现的氨基酸组成基本相似。粪便蛋白质的氨基酸组成与所给日粮蛋白质无关，相对恒定，且大致对应于肠道损失蛋白。TCA可沉淀肽组分与相应粪便蛋白质的氨基酸组成一致。这些组分似乎源自内源性。
