TY - JOUR T1 - Biochemical Dynamics and Sustainable Energy Production in Anaerobic Digestion: Microbial Insights and Innovations TT - Anaerobik Sindirimde Biyokimyasal Dinamikler ve Sürdürülebilir Enerji Üretimi: Mikrobiyal Görüşler ve Yenilikler AU - Kayranlı, Birol AU - Kasapoglu, İrem PY - 2025 DA - June Y2 - 2025 JF - Uluslararası Çevresel Eğilimler Dergisi JO - IJENT PB - Muhammed Kamil ÖDEN WT - DergiPark SN - 2602-4160 SP - 3 EP - 14 VL - 9 IS - 1 LA - en AB - Regarding sustainable wastewater treatment and renewable energy production, anaerobic digestion (AD) is an important technology. This review presents the microbial and biochemical processes involved in methane production in AD systems, focussing mainly on AD of domestic wastewater. The four stages, hydrolysis, acidogenesis, acetogenesis, and methanogenesis are described with relation to microbial consortia, enzymatic activities and coenzymes such as Coenzyme M and F₄₂₀. Recent advances in interspecies electron transfer (IET), in particular direct IET (DIET), also suggest that conductive materials such as biochar increase methane production and system robustness. The metabolism and substrate specificity of methanogenic archaea are discussed and the function of electron carriers in maintaining redox balance. Biogas upgrading technologies, namely membrane separation, pressure swing adsorption, biological scrubbing and hybrid systems are assessed in relation to the methane content and tolerance of microbes. The study highlights the utilization of microbial optimization and technological advancements to enhance the biomethane production in a circular and low carbon spectrum. KW - Anaerobic digestion KW - Biogas upgrading KW - Methane production KW - Coenzymes N2 - Regarding sustainable wastewater treatment and renewable energy production, anaerobic digestion (AD) is an important technology. This review presents the microbial and biochemical processes involved in methane production in AD systems, focussing mainly on AD of domestic wastewater. The four stages, hydrolysis, acidogenesis, acetogenesis, and methanogenesis are described with relation to microbial consortia, enzymatic activities and coenzymes such as Coenzyme M and F₄₂₀. Recent advances in interspecies electron transfer (IET), in particular direct IET (DIET), also suggest that conductive materials such as biochar increase methane production and system robustness. The metabolism and substrate specificity of methanogenic archaea are discussed and the function of electron carriers in maintaining redox balance. Biogas upgrading technologies, namely membrane separation, pressure swing adsorption, biological scrubbing and hybrid systems are assessed in relation to the methane content and tolerance of microbes. 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