An algal regulation-based molasses vinasse anaerobic digestion strategy for enhancing organic matter removal and methane production

Microalgae are suitable type of anaerobic co-digestion (AcoD) substrate that can effectively alleviate microbial inhibition caused by substrate characteristics (molasses vinasse, MV). Therefore, our investigated the synergistic effects, organic matter removal, and potential microbiological impacts in the AcoD of MV and Desmodesmus opoliensis strain GXU-A4. We conducted batch AcoD using simple dehydrated GXU-A4 (Fresh D. opoliensis, FDO) and lipid-extracted GXU-A4 (Pretreated D. opoliensis, PDO). The highest methane potential of PDO biomass was 124.9 ± 0.8 mL g−1 VS, while AcoD with MV increased methane production by 11 % and promoted acetic acid production. FDO biomass reduced nitrogen-containing organic matter and humic-like production. Microbial community and functional prediction analyses revealed that AcoD altered the distribution of hydrolytic acidogenic bacteria, such as Bacteroidetes and Cloacimonadota (W5). Our study provide a new insight into the control strategy of AcoD for methane production, removal of organic matter, and microbial mechanisms in algae biomass. [Display omitted]