in order of effectiveness , the amino acids were : dl-histidine , l-proline , l-hydroxyproline , dl-alanine , l-alanine , dl-aspartic acid , d-alanine , dl-proline , l-serine , l-ornithine , l-glutamic acid , and d-proline .
C0002520
amino acids
C0061472
l-glutamic acid