Question

Why do all amino acids with aromatic side chain give negative results in testing

Answer 1

The test gives a positive result in amino acids carrying aromatic groups, especially in the presence of tyrosine. ... The yellow colour is due to xanthoproteic acid which is formed due to nitration of certain amino acids, most common examples being tyrosine and tryptophan

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Answer 2

Answer:

:The yellow colour is due to xanthoproteic acid which is formed due to nitration of certain amino acids, most common examples being tyrosine and tryptophan