2,3-Butanediol plus acetoin obtention by ATCC 13048: inhibition by target products and cells reuse during fed-batch cultivation.

2,3-Butanediol (2,3-BD) is a highly valued building block, and optimizing its production by fermentation, particularly with crude glycerol, is crucial. is a key microorganism for this process; however, there are limited studies addressing the inhibition effects of products and by-products on 2,3-BD production. This study investigates these inhibition effects to maximize 2,3-BD production. Final concentrations of 2,3-BD plus acetoin reached 89.3, 92.7, and 71.1 g.L with productivities of 1.22, 1.69, and 0.99 g.L.h in pure glycerol, glucose, and crude glycerol media, respectively. Acetic acid was the main by-product, with concentrations ranging from 10 to 15 g.L. The reinoculation of cells highlighted the strong effect of 2,3-BD and acetic acid on microbial growth and metabolism, with the cultivation environment exerting selective pressure. Notably, cells reuse enhanced performance in crude glycerol media, achieving a specific productivity in relation to biomass (Y) of 9.18 g.g; about 25% higher than in fed-batch without cells reuse. By combining results from two fed-batch cycles, the total final concentration of 2,3-BD plus acetoin reached 99.4 g.L, alongside a 33% reduction in total acetic acid production with reused cells.