Comparative analysis of hydrogen-producing bacterial biofilms and granular sludge formed in continuous cultures of fermentative bacteria

• Published in: Bioresource technology Vol. 102; no. 21; pp. 10057 - 10064
• Main Authors: Chojnacka, Aleksandra, Błaszczyk, Mieczysław K., Szczęsny, Paweł, Nowak, Kinga, Sumińska, Martyna, Tomczyk-Żak, Karolina, Zielenkiewicz, Urszula, Sikora, Anna
• Format: Journal Article
• Language: English
• Published: Kidlington Elsevier Ltd 01-11-2011; Elsevier
• Subjects: 454-Pyrosequencing; Applied sciences; Bacteria; Biodiversity; Biofilm; Biofilms - growth & development; Biological and medical sciences; Bioreactors - microbiology; Biotechnology; Cell Culture Techniques - methods; Clostridiaceae; Clostridium - cytology; Clostridium - growth & development; Clostridium - physiology; continuous fermentation; Enterobacteriaceae; Exact sciences and technology; Fermentation - physiology; Food industries; Fundamental and applied biological sciences. Psychology; Granular sludge; hydrogen; Hydrogen - metabolism; Hydrogen fermentation; hydrogen production; lactic acid bacteria; Leuconostocaceae - cytology; Leuconostocaceae - growth & development; Leuconostocaceae - physiology; metagenomics; Methods. Procedures. Technologies; microbial communities; Microbial engineering. Fermentation and microbial culture technology; Molasses; Pollution; production technology; ribosomal DNA; Sewage - microbiology; sludge; sucrose; sugar beet; Use and upgrading of agricultural and food by-products. Biotechnology; Wastes; Biofilm; Molasses; Granular sludge; 454-Pyrosequencing; Hydrogen fermentation; Hydrogen; Chemiluminescence; Fermentation; Continuous process; Bacteria; Wastes; Sequencing; Comparative study
• ISSN: 0960-8524; 1873-2976
• DOI: 10.1016/j.biortech.2011.08.063

► An efficient system for biohydrogen production was presented. ► A high hydrogen yield of 5.43molH2/mol sucrose was achieved. ► 454-Pyrosequencing was used to analyze hydrogen-producing microbial communities. ► The relationship between bacterial consortium structure and the efficiency of hydrogen production was shown.
A system for biohydrogen production was developed based on long-term continuous cultures grown on sugar beet molasses in packed bed reactors. In two separate cultures, consortia of fermentative bacteria developed as biofilms on granitic stones. In one of the cultures, a granular sludge was also formed. Metagenomic analysis of the microbial communities by 454-pyrosequencing of amplified 16S rDNA fragments revealed that the overall biodiversity of the hydrogen-producing cultures was quite small. The stone biofilm from the culture without granular sludge was dominated by Clostridiaceae and heterolactic fermentation bacteria, mainly Leuconostocaeae. Representatives of the Leuconostocaeae and Enterobacteriaceae were dominant in both the granules and the stone biofilm formed in the granular sludge culture. The culture containing granular sludge produced hydrogen significantly more effectively than that containing only the stone biofilm: 5.43 vs. 2.8molH2/mol sucrose from molasses, respectively. The speculations that lactic acid bacteria may favor hydrogen production are discussed.