Anaerobic digestion (AD) has been widely applied for the degradation of organic wastewater due to its advantages of high-load operation and energy recovery. However, some challenges, such as low treatment capacity and instability caused by the accumulation of volatile fatty acids, limit its further application. Here, S. wolfei and G. sulfurreducens were initially co-cultured in the anaerobic anode of bio-electrochemical system for degrading butyric acid. Butyrate degradation characteristics in different conditions were quantitatively described. Moreover, G. sulfurreducens simultaneously strengthened the consumption of H2 and acetic acid via direct interspecies electron transfer, thereby strengthening the degradation of butyric acid via a co-metabolic process. During butyrate degradation, the co-culture of S. wolfei and G. sulfurreducens showed more advantages than that of S. wolfei and methanogens. This present study provides a new perspective of butyrate metabolism, which was independent of methanogens in an AD process.
Keywords: Anaerobic degradation; Butyric acid; Geobacter sulfurreducens; Syntrophism; Syntrophomonas wolfei; Volatile fatty acids.
© 2022. The Author(s), under exclusive licence to Springer Science+Business Media, LLC, part of Springer Nature.