CHYMOSIN B from ASPERGILLUS NIGER var. AWAMORI containing the PROCHYMOSIN B GENE
Prepared at the 53rd JECFA (1999) and published in FNP 52 Add 7 (1999), superseding tentative specifications prepared at the 37th JECFA (1990), published in FNP 52 (1992). ADI "Not specified" established at the 37th JECFA in 1990.
SYNONYMS Rennin, milk-clotting enzyme, chymosin, chymosin B, aspartyl protease
C.A.S. number 85713-24-2
SOURCES Produced extracellularly by the controlled fermentation of Aspergillus niger
var. awamori containing the bovine prochymosin B gene. The strain is nonpathogenic and non-toxicogenic (for example, NRRL 3112). After
inactivation of the production organism, the cellular material is removed by centrifugation or filtration. The enzyme is purified by extraction with
polyethylene glycol, followed by clarification with activated carbon and separation from the solvent by cation exchange chromatography.
Active principles Chymosin
Systematic names and numbers
None (EC 3.4.23.4)
Reactions catalyzed Cleaves a single bond in kappa-casein
DESCRIPTION Clear, colourless or slightly coloured aqueous solutions containing the active enzyme
FUNCTIONAL USES Enzyme preparation
Used in clotting of milk for cheese production
