Degradation of pencillin-V in fermentation media

In Industrial production of penicillin there is a noticeable loss of the product through degradation reactions. It is shown that the degradation of penicillin‐V, both in a complex and in a chemically defined medium, can be separated into a phosphate‐catalyzed conversion of penicillin‐V to penicilloic‐V acid, overlaid by at least one other reaction in which penicillin V is degraded to as yet unknown products. Parameter values for the phosphatecatalyzed degradation are found to be independent of the type of fermentation medium. The rate of formation of other degradation products of penicillin‐V is found to be significantly higher in a complex fermentation medium with corn‐steep liquor in a chemically defined medium. © 1994 John Wiley & Sons, Inc.