Correlation between microbial community and granule conductivity in anaerobic bioreactors for brewery wastewater treatment

• Published in: Bioresource technology Vol. 174; pp. 306 - 310
• Main Authors: Shrestha, Pravin Malla, Malvankar, Nikhil S., Werner, Jeffrey J., Franks, Ashley E., Elena-Rotaru, Amelia, Shrestha, Minita, Liu, Fanghua, Nevin, Kelly P., Angenent, Largus T., Lovley, Derek R.
• Format: Journal Article
• Language: English
• Published: Kidlington Elsevier Ltd 01.12.2014; Elsevier
• Subjects: Alcoholic Beverages; anaerobic ammonium oxidation; anaerobic digestion; Anaerobic treatment; Anaerobiosis; Applied sciences; Bacteria; Bacteria - classification; Bacteria - growth & development; bacterial communities; Beers; Biological and medical sciences; Bioreactors; Bioreactors - microbiology; Biotechnology; Breweries; brewing industry; community structure; Conductive pili; Diets; Direct interspecies electron transfer; Electric Conductivity; electrical conductivity; electron transfer; electrons; Ethanol - analysis; Exact sciences and technology; Fermented food industries; Food industries; Fundamental and applied biological sciences. Psychology; Geobacter; Granular materials; Granules; methanogens; Methods. Procedures. Technologies; phosphates; Pollution; Sequence Analysis, DNA; Sewage - microbiology; Syntrophy; UASB reactor; upflow anaerobic sludge blanket reactor; Upflow anaerobic sludge blanket reactors; Various methods and equipments; Waste Disposal, Fluid; Waste Water - microbiology; Wastes; wastewater treatment; Wastewaters; Water Purification - methods; Water treatment and pollution; Syntrophy; Conductive pili; UASB reactor; Granules; Direct interspecies electron transfer; Brewery; Conductivity; Upflow anaerobic sludge blanket reactor; Electron transfer; Bioreactor; Anaerobe; Granule; Waste water purification; Microbial community
• ISSN: 0960-8524; 1873-2976; 1873-2976
• DOI: 10.1016/j.biortech.2014.10.004

•Granules from four brewery waste UASB digesters were electrically conductive.•Geobacter, Syntrophobacter and Desulfovibrio spp. were the dominant members.•Granules conductivity was moderately correlated with only Geobacter spp. abundance.•This study suggest that Geobacter spp. are a major contributor to conductivity. Prior investigation of an upflow anaerobic sludge blanket (UASB) reactor treating brewery wastes suggested that direct interspecies electron transfer (DIET) significantly contributed to interspecies electron transfer to methanogens. To investigate DIET in granules further, the electrical conductivity and bacterial community composition of granules in fourteen samples from four different UASB reactors treating brewery wastes were investigated. All of the UASB granules were electrically conductive whereas control granules from ANAMMOX (ANaerobic AMMonium OXidation) reactors and microbial granules from an aerobic bioreactor designed for phosphate removal were not. There was a moderate correlation (r=0.67) between the abundance of Geobacter species in the UASB granules and granule conductivity, suggesting that Geobacter contributed to granule conductivity. These results, coupled with previous studies, which have demonstrated that Geobacter species can donate electrons to methanogens that are typically predominant in anaerobic digesters, suggest that DIET may be a widespread phenomenon in UASB reactors treating brewery wastes.