Chlorogenic Acid Targets Cell Integrity and Virulence to Combat Vibrio parahaemolyticus

Vibrio parahaemolyticus is a primary foodborne pathogen in seafood that endangers consumers' health. It is vital to develop novel prevention and control strategies due to its extensive transmission and drug resistance. This work aimed to examine the antibacterial and anti-virulence efficiency of chlorogenic acid (CA) against V. parahaemolyticus. The minimum inhibitory concentration (MIC) of CA is 6 mg/mL. CA realized its antibacterial effect by damaging the cell wall and membrane, evidenced by the leakage of alkaline phosphatase, intracellular proteins and nucleic acids, potassium ion, and glucose, the increasing malondialdehyde and reactive oxygen species, as well as morphological observations under scanning and transmission microscopes and live and dead cell observations under laser confocal microscopy. When V. parahaemolyticus was treated with CA at sub-inhibitory doses, its hydrophobicity, extracellular polysaccharide synthesis, motility, and biofilm formation were all significantly inhibited. Moreover, CA effectively protected salmon from the contamination of V. parahaemolyticus with a prolonged shelf life. These findings indicate that CA possesses antibacterial activity against V. parahaemolyticus, suggesting its potential value for controlling V. parahaemolyticus-associated seafood infections.