CONTENTS OF PART I. 



PAGE 



INTRODUCTION i 



I. HYDROLYSIS 9 



II. THE ISOLATION AND ESTIMATION OF THE UNITS - 15 



A. THE MONO-AMINO ACIDS - 1 7 



TYROSINE - 17 



(1) Isolation and Gravimetric Estimation - 17 



(2) Colorimetric Estimation - 20 



(3) Estimation by Bromination - 2 2 



CYSTINE - - 24 



(1) Isolation and Gravimetric Estimation - 24 



(2) Separation of Cystine and Tyrosine - 25 

 TRYPTOPHAN - 27 



(1) Isolation and Gravimetric Estimation - -27 



(2) Colorimetric Estimations - 28 



(3) Estimation by Bromination - 32 

 THE OTHER MONO-AMINO ACIDS - - 33 



(1) Isolation of Glutamic Acid as Hydrochloride - 33 

 (ia) Isolation of Glutamic Acid as Zinc Salt - - 34 

 (ib) Isolation of Glutamic and Aspartic Acids as Silver Salts 34 

 (ic) Isolation of Glutamic and Aspartic Acids as Calcium Salts 34 



(2) Esterification - - 35 



(3) Isolation of Glycine as Ester Hydrochloride - - 36 



(4) Extraction of the Esters of the Amino Acids - - 37 



(5) Fractional Distillation of the Esters in Vacua - 40 



(6) The Isolation of the Individual Mono-amino Acids - 42 



(a) Proline - 43 



(b) Glycine, Alanine, Valine, Leucine, and Isoleucine - - 44 

 i. Separation of Valine from Leucine and Isoleucine - - 45 

 ii. Valine - 46 

 iii. Leucine and Isoleucine - 47 

 iv. Separation of Valine and Alanine - - 48 

 v. Separation of Glycine and Alanine - 5 1 



(c) Phenylalanine - 52 



