The antibacterial action of 4:6-dimethoxytoluquinone and its fate in the animal body

Abstract

In vitro 4,6-dimethoxytoluquinone and 4,6-dimethoxytoluquinol were highly active against the Gram-positive organisms {Streptococcus pyogenes, Staphylococcus aureus, Diplococcus pneumoniae (Type I) and Clostridium perfringens) and to a lesser extent against the Gram-negative bacteria (Pseudomonas aeruginosa, Proteus vulgaris, and Escherichia coli). The quinone is also fungicidal against Adinomyces praetorianus and Trichophyton lacticolor in concs. of 1:100,000. The bacteriostatic activity of 4,6-dimethoxytoluquinone was decreased in the presence of serum and abolished in the presence of blood. Oral administration gave no protection in mice infected with S. pyogenes or Staph. aureus and local injns. were ineffective against exptl. C. perfringens infections. In concs. of 1:40,000 the quinone inhibited the growth of chick-heart embryo fibroblasts in tissue culture and reduced the phagocytic action of leucocytes. 4,6-dimethoxytoluquinone is rapidly conjugated with glu-curonic acid when administered orally to rabbits and appears in the urine in this form within 30 min. The glucuronide has no antibacterial activity. Toluquinone is detoxified by conjugation with amino acids and not glucuronic acid. Neither free nor acid hydrolyzable conjugated quinone can be recovered from feces.