(592f) Fermentation and Nutrient Characterization of Hydrolysate From AFEX-Pretreated Corn Stover

Nutrient characteristic of a fermentation medium determines the efficacy of fermentation. Ammonia, amino acids, vitamins and trace elements are the essential categories of nutrients which are required by fermenting strains at varying concentrations and these requirements might differ depending on the strain selection.

Fermentation using lignocellulosic materials as carbon source offers a promising route for various bio-based chemicals production. However, the nutrient profile of the lignocellulosic hydrolysate remains unclear. Therefore, we are analyzing important nutrient components present in hydrolysate from AFEX pretreated corn stover, both quantitatively and qualitatively; identifying limiting or excess nutrients to fundamentally understand the fermentability of AFEX hydrolysate from corn stover. We address the issue regarding the source (feedstock, pretreatment and enzymatic hydrolysis) of the nutrients in hydrolysate. This development will enable us to (i) Evaluate the need for further nutrient reformulation of the hydrolysate and (ii) Rationally supplement (or remove) certain nutrients to achieve optimal fermentations.

Furthermore, we also seek to investigate the fermentation of AFEX-treated feedstock using E. coli KO11, Z. mobilis AX101 and S. cerevisiae 424A(LNH-ST) based on nutrients provided through biomass. Through these evaluations, we establish a foundation for effective lignocellulosic fermentation with little (or no) dependence on external nutrient sources.