Metagenomic Analysis of Bacterial, Archaeal and Fungal Diversity in Two-Stage Anaerobic Biodegradation for Production of Hydrogen and Methane from Corn Steep Liquor

• Published in: Microorganisms (Basel) 2023-05, Vol.11 (5), p.1263
• Main Authors: Stoyancheva, Galina, Kabaivanova, Lyudmila, Hubenov, Venelin, Chorukova, Elena
• Format: Article
• Language: English
• Subjects: Acetogenesis; Acid production; Alternative energy sources; Anaerobic biodegradation; Anaerobic conditions; Anaerobic digestion; Anaerobic microorganisms; Anaerobic processes; Annealing; Archaea; Bacteria; Biodegradable materials; Biodegradation; Biodiesel fuels; Biofuels; Biogas; Bioinformatics; Bioreactors; Biotechnology; Cellulose; Clean energy; Clean technology; Consortia; Controlled conditions; Corn; Corn products; Environmental impact; Fatty acids; Fermentation; Food industry; Fungi; Genetic aspects; Green energy; green energy production; Hydrogen; Hydrogen production; Identification and classification; Liquor; Metagenomics; Methane; Methanogenesis; Methanogenic archaea; Methods; Microbial activity; Microorganisms; Optimization; Organic matter; Production processes; Raw materials; Renewable resources; Sequences; Substrates; Volatile fatty acids; waste utilization; Wastes
• ISSN: 2076-2607; 2076-2607
• DOI: 10.3390/microorganisms11051263

The main purpose of this study was to identify the microbial communities (bacterial, archaeal and fungal) in a two-stage system of anaerobic bioreactors for the production of hydrogen and methane from the waste substrate-corn steep liquor. Wastes from the food industry are valuable resources with potential in biotechnological production because of their high organic matter contents. In addition, the production of hydrogen and methane, volatile fatty acids, reducing sugars and cellulose content was monitored. Two-stage anaerobic biodegradation processes were performed by microbial populations in the first hydrogen generating bioreactor (working volume of 3 dm ) and in the second methane-generating reactor (working volume of 15 dm ). Cumulative hydrogen yield reached 2000 cm or 670 cm /L a day, while the methane production reached a maximum quantity of 3300 cm or 220 cm /L a day. Microbial consortia in anaerobic digestion systems play an essential role for process optimization and biofuel production enhancement. The obtained results showed the possibility of conducting two separate processes-the hydrogenic (hydrolysis and acidogenesis) and methanogenic (acetogenesis and methanogenesis)-as two stages of anaerobic digestion to favor energy production under controlled conditions with corn steep liquor. The diversity of microorganisms as main participants in the processes in the bioreactors of the two-stage system was followed using metagenome sequencing and bioinformatics analysis. The obtained metagenomic data showed that the most abundant phylum in both bacterial communities was -58.61% and 36.49% in bioreactors 1 and 2, respectively. Phylum were found in significant quantities (22.91%) in the microbial community in Bioreactor 1, whereas in Bioreactor 2, they were 2.1%. are present in both bioreactors. Phylum made up 0.4% of the contents in the first bioreactor and 11.4% in the second. As the dominant genera among methanogenic archaea are (8.03%) and (3.39%), the main fungal representatives were . New knowledge of anaerobic digestion mediated by novel microbial consortia could be widely used to convert different wastes to green energy.