| abstract |
A process for preparing an active animal cell-growth-enhancing fraction of a hydrolysate of plant tissue, animal tissue or microorganism ultrafiltrate material, especially a fraction of a yeastolate ultrafiltrate, comprising forming a precipitate from said fraction with a water-soluble solvent is disclosed. Such solvents as alkanols, alkyl sulfoxides, ketones or alkyl nitriles, especially lower (C1 - C5) alkanols, particularly ethanol, can be used. The invention also relates to an active animal cell-growth-enhancing fraction of a hydrolysate of plant tissue, animal tissue or microorganism ultrafiltrate material, especially a fraction of a yeastolate ultrafiltrate, substantially free of aromatic and methyl group bearing compounds which has improved cell-growth-enhancing properties. |