Microbial diversity in innovative mesophilic/thermophilic temperature-phased anaerobic digestion of sludge

• Published in: Environmental science and pollution research international 2015-05, Vol.22 (10), p.7339-7348
• Main Authors: Gagliano, M. C., Braguglia, C. M., Gallipoli, A., Gianico, A., Rossetti, S.
• Format: Article
• Language: English
• Subjects: Alternative energy sources; Anaerobic digestion; Anaerobic microorganisms; Anaerobiosis; Aquatic Pollution; Atmospheric Protection/Air Quality Control/Air Pollution; Bacteria; Bacteria - genetics; Bacteria - growth & development; Bacteria - isolation & purification; Bacteria - metabolism; Biodegradation, Environmental; Biodiversity; Biogas; Biomass; Bioreactors - microbiology; Chemical oxygen demand; Clean technology; Cooperation; Earth and Environmental Science; Ecotoxicology; Effective Management of Sewage Sludge; Environment; Environmental Chemistry; Environmental Health; Fluorescence in situ hybridization; Hybridization; In Situ Hybridization, Fluorescence; Investigations; Population studies; Protein composition; Reactors; Retention; Sensors; Sewage - microbiology; Sewage sludge; Sludge; Sludge digestion; Species richness; Temperature; Thermophilic microorganisms; Ultrasonic imaging; Waste streams; Waste treatment; Waste Water Technology; Water Management; Water Pollution Control
• ISSN: 0944-1344; 1614-7499
• DOI: 10.1007/s11356-014-3061-y

Anaerobic digestion (AD) is one of the few sustainable technologies that both produce energy and treat waste streams. Driven by a complex and diverse community of microbes, AD may be affected by different factors, many of which also influence the composition and activity of the microbial community. In this study, the biodiversity of microbial populations in innovative mesophilic/thermophilic temperature-phased AD of sludge was evaluated by means of fluorescence in situ hybridization (FISH). The increase of digestion temperature drastically affected the microbial composition and selected specialized biomass. Hydrogenotrophic Methanobacteriales and the protein fermentative bacterium Coprothermobacter spp. were identified in the thermophilic anaerobic biomass. Shannon–Weaver diversity ( H ′) and evenness ( E ) indices were calculated using FISH data. Species richness was lower under thermophilic conditions compared with the values estimated in mesophilic samples, and it was flanked by similar trend of the evenness indicating that thermophilic communities may be therefore more susceptible to sudden changes and less prompt to adapting to operative variations.