Implementation of two-stage fermentation for improving the volumetric productivity of L-phenylalanine and cinnamic acid production

Increasing concern on global greenhouse gas emissions, rising cost of petroleum and a general desire for environmentally friendly processes is driving the development of new bioprocess routes using whole-cell biocatalyst for production of sustainable chemical-based products [1]. One of the huge challenges to compete with traditional chemical processes or petroleum-based production is that many times production metrics (titer, rate and yield; TRY), need to be improved. Two-stage fermentation, separation of the growth phase from the production phase, can be used in order to improve volumetric productivity of Lphenylalanine and cinnamic acid production, an aromatic compound that commonly used together with their esters in a broad range of industries, such as flavor compound in food and drink, cosmetics and surgical applications [2-3].

This study aims to develop two-stage fermentation of bioengineered microorganisms to improve the volumetric productivity of Lphenylalanine and cinnamic acid production under an inducer. The influence of initial biomass concentration on the production stage, substrate feeding strategies and cell recycling are investigated to control the biosynthesis along with optimization of the crucial fermentation parameters. Finally, this work will provide the basis for two-stage fermentation of L-phenylalanine and cinnamic acid production by an engineered strain that suitable for large scale fermentation.