Ascorbic Acid-Mediated Modulation of Antibiotic Susceptibility of Major Bovine Mastitis Pathogens

This study aimed to investigate the effects of ascorbic acid on antibiotic susceptibility of major bovine mastitis pathogens, including Staphylococcus aureus, Streptococcus dysgalactiae, Streptococcus uberis, Streptococcus agalactiae, and Escherichia coli. Minimum inhibitory concentrations (MICs) were determined by E-test method. The presence of 10 mM ascorbic acid decreased the MICs of penicillin and ampicillin while increased the MICs of erythromycin, kanamycin, streptomycin, and ciprofloxacin for all tested strains. Besides, ascorbic acid specifically reduced the MICs of tetracycline for gram-positive bacteria and chloramphenicol for gram -negative bacteria. This study highlights that ascorbic acid is a potential modulator of antibiotic activity against the major bovine mastitis pathogens.

Automated summary

This study aimed to investigate the effects of ascorbic acid on antibiotic susceptibility of major bovine mastitis pathogens. The results showed that ascorbic acid could decrease the susceptibility of penicillin and ampicillin, while increase the susceptibility of erythromycin, kanamycin, streptomycin, and ciprofloxacin. Moreover, ascorbic acid specifically reduced the susceptibility of tetracycline for gram-positive bacteria and chloramphenicol for gram-negative bacteria.