RT Journal Article
T1 Chain elongation may occur in protein mixed-culture fermentation without supplementing electron donor compounds
A1 Bevilacqua, Riccardo
A1 Regueira López, Alberte
A1 Mauricio Iglesias, Miguel
A1 Lema Rodicio, Juan Manuel
A1 Carballa Arcos, Marta
K1 Resource recovery
K1 Amino acids
K1 Biorefinery
K1 Carboxylate platform
K1 Chain elongation
K1 Protein waste
AB This study focuses on verifying the occurrence of elongation processes during protein mixed culture fermentation, without the supplementation of electron donor compounds. During casein mixed-culture fermentation at pH 5, it was observed that longer chain volatile fatty acid production increased, which could not be justified by the associated amino acid consumption. Consequently, the occurrence of chain elongation processes was hypothesized. To verify this hypothesis, three casein batch tests, with and without acetic acid initial supplementation, were performed at pH 5. The results suggest that acetic and propionic acids are indeed consumed to selectively generate n-valeric acid through the coupling with electron donor amino acids, whose consumption was further verified through the amino acid analysis. Prolonged simultaneous availability of suitable amino acids and short chain volatile fatty acids and an acid equivalent concentration threshold were identified as key parameters for the occurrence of chain elongation. The supplementation of acetic acid at the beginning of the test changed the selectivity of the elongation process, promoting n-butyric and iso-valeric production. The associated mechanisms were preliminary conceptualized, constituting a first step for further studies on the subject. To the best of our knowledge, this is the first study demonstrating the feasibility of chain elongation processes during protein mixed culture fermentation without electron donor supplementation
PB Elsevier
YR 2022
FD 2022
LK http://hdl.handle.net/10347/27701
UL http://hdl.handle.net/10347/27701
LA eng
NO Journal of Environmental Chemical Engineering 10 (2022) 106943. https://doi.org/10.1016/j.jece.2021.106943
NO This project has received funding from the Spanish Government through BIOCHEM project (PCIN-2016-102, ERA-IB-2 7th call, ERA-IB-16-052)
DS Minerva
RD 1 may 2026