[Comparative balance study of the value of amino acids for humans after oral and parenteral input].

The biological value (BV) of an amino acid mixture, according to the potato-egg principle (KE), was determined in the case of oral and parenteral input with three healthy adult volunteers in a long-term complete test of metabolic balance: KE-amino acid pattern with oral input, BV=134.4; KE-amino acid pattern with parenteral input, BV= 131.4; egg protein (reference) with oral input, BV=100. The long-term metabolic balance experiment with human subjects under criteria of compensated nitrogen balances was used to test nitrogen substances like whole egg protein and amino acids (under parenteral and oral input); the BV of a nitrogen substance is defined as the reciprocal value of the minimum nitrogen requirements compared with the reference protein whole egg, which is set at 100. The results confirm in principle (1) the almost identical utilization and value of identical nitrogen substances (amino acids), even with different ways of input with oral and parenteral nutrition of the human being, and (2) the ability of reproduction of the BV of the optimal potato-egg protein mixture (65% potato nitrogen + 35% egg nitrogen with oral input: BV = 137.6) by means of simulation through corresponding L-amino acids, considering the modification necessary for technical as well as physiological reasons, which concern the non-essential part of the pattern.