Tryptophan from China
L-Tryptophan is an essential amino acid featuring an indole side chain attached to alanine, classified under HTS 2933.99.0500 due to its indole structure. The heterocyclic nitrogen compound takes precedence over amino acid classification.
Duty Rate — China → United States
12.5%
Rate breakdown
9903.05.3112.5%Section 301 (forced labor) — additional 12.5% ad valorem on products of China
Import Tips
• Indole amino acids classified here, not with other amino acids, per heterocyclic precedence
• Pharma grade requires USP certificate; feed grade may have different documentation
• Avoid Chapter 29 note 3(C) salt classification issues with pure free acid form