[Blood amino acids in astronauts before and after a 211-day space flight]

The plasma content of 17 free amino acids of the Commander and Flight-Engineer of Salyut-1-Soyuz-T was examined before flight and on postflight days 1 and 7. The amino acids were measured in an automatic amino acid analyzer Hitachi KLA-3B. Both cosmonauts showed a decrease of most amino acids, particularly essential amino acids. On postflight day 7 the content of most amino acids did not yet return to the preflight level. It can therefore be concluded that the preflight diet should be supplemented with methionine and aspartic acid, and the flight and postflight diets with 7 essential amino acids plus cystine, arginine, proline and aspartic acid.