Synthesis of α - amino acids 

Protein can be hydrolyzed by refluxing with dilute hydrochloric acid to give a mixture of α - amino acids. The resulting mixture can be separated by 
(a)    fractional crystallization. 
(b)    Fractional distillation of their ester followed by hydrolysis (Fischer’s method)
(c)    Selective precipitation as salt with phosphotungstic and picric acid. 
(d)    Distribution of amino acid between n – butanol saturated with water (Dakin’s method). 
(e)    Column, paper and gas chromatography. 
(f)    Electrophoresis.

By amination of α- halo acid

By Strecker Synthesis

(i)

(ii)

Note: Generally the aldehyde is treated with a mixture of ammonium chloride and potassium cyanide in aqueous solution

Solved Example:

(D)    All are correct
Solution:        (C)

Physical properties of amino acid 
(i)    Amino acids are generally, crystalline substance having sweet taste. 
(ii)    They melt with decomposition at higher temperature (more than 200°C).
(iii)    They are soluble in water but insoluble in organic solvents