Amino Acids and Ammonia of Fetal Calf Serum During Storage.

Abstract

Summary 1. Unnltered fetal calf serum undergoes no change in growth-promoting activity during storage at 5° for 3 months. Six days' storage at 37° results in a loss of activity. 2. Incubation at 37° results in a significant decrease in glutamine and significant increases in hydroxyproline, proline, glutamic acid and phenylalanine. 3. The most notable change was an increase in ammonia from 0.54 to 9.05 μmoles/ml after 21 days' incubation. Addition of ammonium chloride to the Strain L cells at concentrations equivalent to those found in the incubated fetal calf serum produced inhibition of the growth of Strain L cells.