ANTIBACTERIAL ACTIVITY OF SEVERAL ORGANIC -ACIDS COMMONLY USED AS FOOD-ADDITIVES

Among 9 organic acids commonly used as food additives in Japan, fumari c acid (FA) exhibited the strongest growth-inhibiting (GI) action on 2 0 Gram-negative bacterial strains tested. Growth of these 20 strains, including 3 Salmonella serovars, Escherichia coli, E. cloacae, Klebsie lla oxytoca, K. pneumoniae, Acinetobacter anitratus, Proteus mirabilis , or Pseudomonas aeruginosa, was inhibited within 160 seconds of conta ct with 0.3 w/v% solution of FA, although strains of S. Typhimurium ex hibited lower susceptibility than the others. Both Bacillus cereus and Staphylococcus aureus were resistant to the GI action of FA and other organic acids. The GI action of FA was remarkably improved by the add ition of 0.3 similar to 0.1% ascorbic acid, malic acid, tartaric acid or citric acid monohydrate.