Abstract
Liver xanthine oxidase (XOD) and superoxide dismutase (SOD) activities were compared in mice during Salmonella typhimurium and Pseudomonas aeruginosa infections. We observed that XOD activity rose but SOD activity fell for the first 11 days after infection with smooth type S. typhimurium, coinciding with the period of bacterial growth in the liver. Rough type S. typhimurium did not establish an infection and mice inoculated with this strain showed no variation in enzyme activities. P. aeruginosa infection was mild but stimulated both XOD and SOD activities.