Biomethane upgrading from dairy wastes via microbial cell-to-cell signaling molecules
Year: 2025
Type: article
Abstract: Anaerobic digestion (AD) of wastewater treatment plant (WWTP) sludge is commonly practiced but often yields suboptimal methane production due to substrate limitations. This study explores a novel strategy to enhance biogas and methane production by co-digesting WWTP sewage sludge with a lipid-rich residue from cheese factory wastewater treatment plant —dairy waste greases— and stimulating microbial activity using the quorum sensing (QS) molecule N-dodecanoyl-L-homoserine lactone (12-HSL). An 80:20 ratio of sewage sludge to grease achieved high biogas volume (700 NmL CH4 /g VS ) with ∼70 % methane content. The addition of 12-HSL significantly boosted methane production, with the most pronounced effect (38 % increase in methane yield and 33 % in biogas volume) observed when applied on day 4 of digestion. Metagenomic analysis revealed that 12-HSL modulated the microbial community, enriching key hydrolytic and methanogenic populations—particularly Halobacterota —and upregulating pathways related to signal transduction, stress tolerance, and substrate degradation. These findings demonstrate that QS-based biostimulation is a promising tool to improve methane yields and microbial efficiency in anaerobic digestion of water treatment systems, offering a scalable microbiome-driven tool to improve energy recovery, reduce organic loads, and support circular resource use.
Source: Biomass and Bioenergy
Authors: Ángela Lao-Zea, M. Luisa Lorenzo, María del Prado García-Aparicio, Isabel Higueras, Javier Contreras, Raquel Iglesias, Miguel G. Acedos
Language: English
Subfield: Building and Construction
Field: Engineering
Domain: Physical Sciences
Open Access status: hybrid
Estimated APC paid: $4,270
OpenAlex ID: W7110323364