[Effects of H2O2 addition on cell growth and product formation in long-chain dicarboxylic acid fermentation].

When Candida tropicalis was cultivated in shakig-flask with the H2O2 addition, DCA (Dicarboxylic Acid, DCA) concentration was increased, especially at 2 mmol/L H2O2 concentration. The cytochrome P450 activity assays indicated that H2O2 addition significantly increased the activities of cytochrome P450 and DCA production positively correlated with the activities of cytochrome P450. The study on the cell growth demonstrated that the H2O2 addition inhibited the cell growth rate. However, the retarding effect was not irreversible since the cell growth rate could recover slowly to the original level after the H2O2 addition was halted. The mechanism of inducement on cytochrome P450 by H2O2 addition was also discussed in this article.