Efficient Co-Utilization of Biomass-Derived Mixed Sugars for Lactic Acid Production by Bacillus coagulans Azu-10

Lignocellulosic and algal biomass are promising substrates for lactic acid (LA) production. However, lack of xylose utilization and/or sequential mixed-sugars (carbon catabolite repression, CCR) from hydrolysates by most microorganisms limits achievable titers, yields, productivities economical industry-scale This study aimed to design lignocellulose-derived efficient LA production a thermophilic, xylose-utilizing, inhibitor-resistant Bacillus coagulans Azu-10. strain produced 102.2 g/L 104 at yield 1.0 g/g productivity 3.18 g/L/h. The CCR effect were investigated using different mixtures glucose (G), cellobiose (C), (X). Strain Azu-10 has efficiently co-utilized GX CX mixture without CCR; however, total substrate concentration (>75 g/L) was the only limiting factor. completely consumed homoferemnatively up 76.9 g/L. On other hand, fermentation with GC exhibited obvious where both (>25 sugar (>50 factors. A maximum 50.3 0.93 2.09 Batch GCX achieved 62.7 0.962 1.3 Fermentation best Fed-batch 83.6 0.895 1.39