The amino acid requirements of Neocallimastix sp N 13 isolated from sheep rumen were studied using supplements containing either ten essential amino acids (10 EAA) or eight nonessential amino acids (8 NEAA), or both (18 AA). Although the fungus could grow in a medium containing ammonium sulphate as the sole source of nitrogen, amino acid supplements, especially 18 AA, greatly stimulated its gro...
