Casamino acid
Casamino acids are a mixture of amino acids and some very small peptides obtained from acid hydrolysis of casein [1] It is typically used in microbial growth media. It has all the essential amino acids except tryptophan which becomes almost destroyed when digested with sulfuric or hydrochloric acid.[1]
Casamino acids are similar to tryptone, the latter differing by being an incomplete enzymatic hydrolysis with some oligopeptides present, while casamino acids are predominantly free amino acids.
Uses
Casamino acids are either found in the Daptacel brand DTaP vaccine or used in its manufacture.[2] Casamino Acids is a hydrochloric acid hydrolysate of casein. Supplies a completely hydrolyzed protein nitrogen source. It contains a small amount of cystine. Tryptophan and vitamins are destroyed by the acid treatment. The remaining amino acids (in varying amounts) are a source of nutrients for various microorganisms. Amino acids are highly soluble and suitable for use in tissue culture. Salt content is typically 30-40%.
Appearance: White to light tan, homogenous, free flowing powder Solubility (2%) Colourless to light yellow, clear in solution
References
- 1 2 Mueller, J. Howard; Johnson, Everett R (1 Jan 1941). "Acid Hydrolysates of Casein to Replace Peptone in the Preparation of Bacteriological Media". The Journal of Immunology. 40 (1): 33–38. ISSN 1550-6606.
- ↑ http://www.cdc.gov/vaccines/pubs/pinkbook/downloads/appendices/B/excipient-table-2.pdf