On-line monitoring of penicillin V during penicillin fermentations: a comparison of two different methods based on flow-injection analysis

✍ Scribed by Morten Carlsen; Claus Johansen; Rong Wei Min; Jens Nielsen; Helmut Meier; Francois Lantreibecq

• Publisher: Elsevier Science
• Year: 1993
• Tongue: English
• Weight: 666 KB
• Volume: 279
• Category: Article
• ISSN: 0003-2670
• DOI: 10.1016/0003-2670(93)85065-r

✦ Synopsis

Two different flow-injection analysis (FIA) methods used for on-line monitoring of penicillin V during fed-batch penicillin fermentations are compared. The fermentations are carried out using a high yielding strain of Perzicillium chrysogenum and both analyzers are used continuously for on-line monitoring during 200 h. Both methods are based on a reaction catalyzed by p-lactamase, which converts penicillin V to penicilloic acid. In analyzer 1 the sample is injected into a buffer stream and carried to a stirred measurement cell containing an enzyme electrode. The enzyme electrode consists of /%lactamase immobilized onto a sensitive pH glass electrode with a very low response time. No predilution of the sample is required in this analyzer. In analyzer 2 the sample is injected into an enzyme reactor containing immobilized &lactamase. The formed penicilloic acid is detected by decolorization of an iodine-starch complex. By means of a second injection valve it is possible to have the sample by-pass the enzyme reactor and instead pass a dummy reactor in which no P-lactamase is immobilized. Thereby both the concentration of penicillin and penicilloic acid can be measured. On-line dilution of the sample is ensured by a gradient technique. Experimental results from on-line monitoring of penicillin V using the two methods are presented. The large amount of precise measurements enables a very good resolution of the penicillin production; something of extreme value for verification of mathematical models describing the fermentation kinetics.