E. Staten Wynne

Enzymic hydrolysis of plasma proteins for microbiological assays of amino acids.

Abstract In microbiological assays of human plasma for arginine, glycine, histidine, isoleucine, tryptophan, and tyrosine, maximal values were obtained using hydrolysis with pepsin for 2 h at 55° C followed by trypsin for 16 h at 45° C. Prolongation of the trypsin treatment for 48 h or more resulted in greatly decreased values for arginine. With formol titration as an indicator of hydrolysis, maximal values were secured only after treatment with pepsin for 6 or 24 h, followed by trypsin for at least 48 h. Assay values of all amino acids from enzymic hydrolysates were as high as those from acid hydrolysates, and were considerably higher in the case of glycine.