Optimizing the production of Escherichia coli MG1655 ε- Fermentation conditions of polylysine

Abstract

In recent years, with the improvement of people's material living standards, the public health concept has been gradually enhanced, and food preservatives, as a key factor in food safety, have been highly valued by the state and society. Compared with chemical preservatives, more green, more efficient, non-toxic natural preservatives are favored by more and more consumers.ε -Polylysine (ε -poly-L-lysine, ε -PL), as a natural preservative made of lysine, has the advantages of excellent antibacterial effect, soluble in water, strong thermal stability, biodegradable, and safety and high efficiency. In this study, using univariate and response surface analysis to explore the fermentation conditions of ε -PL, the optimal fermentation conditions for ε -polylysine production were 60.29 g glucose, 7.49 g yeast powder, 12.08 g ammonium sulfate, and the predicted value of ε -polylysine was 0.2953 g / L. To test the accuracy of this response surface method, a shake flask fermentation experiment with ε -polylysine was performed to obtain an average yield of ε -polylysine of 0.286 ± 0.016 g / L. The result varies slightly from the predicted value of the model, which proves the accuracy of the model and has some practical value.