l-tryptophan

Classifications are made based on the available commercial supply of the ingredient, and are made based on the criteria on our classifications page.

Commercially available l-tryptophan may be vegan depending on the source and may be vegetarian depending on the source.

L-tryptophan is an essential amino acid. The most common manufacturing technique for tryptophan is bacterial fermentation. Although the bulk of the material fed comes from corn and other plant sources, some of the vitamins and minerals may come from animal sources (see amino acid).

Sources

1. Burnett, C. L., Heldreth, B., Bergfeld, W. F., Belsito, D. V., Hill, R. A., Klaassen, C. D., Liebler, D. C., Marks, J. G., Shank, R. C., Slaga, T. J., Snyder, P. W., & Andersen, F. A. (2013). Safety Assessment of α-Amino Acids as Used in Cosmetics. International Journal of Toxicology, 32(6_suppl), 41S–64S.
   https://doi.org/10.1177/1091581813507090
2. Ikeda, M. (2002). Amino Acid Production Processes. Microbial Production of L-Amino Acids, 1–35.
   https://doi.org/10.1007/3-540-45989-8_1