Adaptive resilience of a coculture system: harnessing high-level hydrogen sulfide stress for enhanced biogas utilization

• Main Authors: Zhang, Baorui, Liu, Jianbo, Cai, Chen, Zhou, Yan
• Other Authors: Interdisciplinary Graduate School (IGS)
• Format: Conference or Workshop Item
• Language: English
• Published: 2024
• Subjects: Earth and Environmental Sciences; Methanotroph-microalgae-heterotroph coculture; Biogas utilization; Hydrogen sulfide stress and response
• Online Access: https://hdl.handle.net/10356/180075; https://iwa-network.org/events/nutrient-removal-and-recovery-conference-2024/
• Institution: Nanyang Technological University

This study investigated the effects of H2S on a methanotroph-microalgae-heterotroph coculture system using a long-term continuous flow photobioreactor. The results showed that the coculture system could tolerate H2S concentrations up to 1000 ppm without significant changes in methane (CH4) and carbon dioxide (CO2) consumption rates, primarily through alterations in population structure and metabolic pathway adjustments. However, exposure to 5000 ppm H2S for one month led to a re-establishment of symbiotic equilibrium, resulting in a threefold increase in both CH4 and CO2 consumption rates from its initial level of approximately 100 to 300 mg C/mg VSS per day. This suggests that the impact of H2S on the symbiotic system is both time and concentration dependent. Notably, the content of the main byproduct, protein, which constituted over 50% of the cell dry weight, was not affected by H2S exposure.