Molecules, Vol. 29, Pages 1908: Volatile Fatty Acids Effective as Antibacterial Agents against Three Enteric Bacteria during Mesophilic Anaerobic Incubation

Molecules, Vol. 29, Pages 1908: Volatile Fatty Acids Effective as Antibacterial Agents against Three Enteric Bacteria during Mesophilic Anaerobic Incubation Molecules doi: 10.3390/molecules29091908 Authors: Saanu Victoria Otite Alfonso José Lag-Brotons Lawrence I. Ezemonye Alastair D. Martin Roger W. Pickup Kirk T. Semple The antibacterial effects of a selection of volatile fatty acids (acetic, propionic, butyric, valeric, and caproic acids) relevant to anaerobic digestion were investigated at 1, 2 and 4 g/L. The antibacterial effects were characterised by the dynamics of Enterococcus faecalis NCTC 00775, Escherichia coli JCM 1649 and Klebsiella pneumoniae A17. Mesophilic anaerobic incubation to determine the minimum bactericidal concentration (MBC) and median lethal concentration of the VFAs was carried out in Luria Bertani broth at 37 °C for 48 h. Samples collected at times 0, 3, 6, 24 and 48 h were used to monitor bacterial kinetics and pH. VFAs at 4 g/L demonstrated the highest bactericidal effect (p < 0.05), while 1 g/L supported bacterial growth. The VFA cocktail was the most effective, while propionic acid was the least effective. Enterococcus faecalis NCTC 00775 was the most resistant strain with the VFAs MBC of 4 g/L, while Klebsiella pneumoniae A17 was the least resistant with the VFAs MBC of 2 g/L. Allowing a 48 h incubation period led to more log decline in the bacterial numbers compared to earlier times. The VFA cocktail,...
Source: Molecules - Category: Chemistry Authors: Tags: Article Source Type: research