Succinate production from CO2-grown microalgal biomass as carbon source using engineered Corynebacterium glutamicum through consolidated bioprocessing

The potential for production of chemicals from microalgal biomass has been considered as an alternative route for CO2 mitigation and establishment of biorefineries. This study presents the development of consolidated bioprocessing for succinate production from microalgal biomass using engineered Corynebacterium glutamicum. Starch-degrading and succinate-producing C. glutamicum strains produced succinate (0.16 g succinate/g total carbon source) from a mixture of starch and glucose as a model microalgal biomass. Subsequently, the engineered C. glutamicum strains were able to produce succinate (0.28 g succinate/g of total sugars including starch) from pretreated microalgal biomass of CO2-grown Chlamydomonas reinhardtii. For the first time, this work shows succinate production from CO2 via sequential fermentations of CO2-grown microalgae and engineered C. glutamicum. Therefore, consolidated bioprocessing based on microalgal biomass could be useful to promote variety of biorefineries.