Q. The $\alpha -$amino acid which doesn’t give purple colour in the ninhydrin test is
A) Proline
B) Glycine
C) Lysine
D) Aspartic acid
Explanation
(a)
Ninhydrin test is highly specific for primary amines. Proline being a secondary amine gives a yellow orange colour with ninhydrin whereas all other $\alpha -$amino acids give a blue-purple colour with ninhydrin.
Reviewed by Dr. Abubacker
Physics Educator & NEET/JEE Specialist
Ph.D. in Physics with 19+ years of teaching experience.