Antibacterial Effect of Tertiary Butylhydroquinone Against Two Genera of Gram Positive Cocci

The minimum inhibitory concentration (MIC) of tertiary butylhydroquinone (TBHQ) against Pediococcus pentosaceus in a bacteriological medium was 15 μg/ml for 10 3 to 10 5 cells/ml and 20 μg/ml for 10 6 cells/ml. Heat stress and sodium chloride were each synergistic to the inhibitory effect of TBHQ. Production of both L and D lactic acid was inhibited by TBHQ. Fermentation of sucrose was totally inhibited by 5 μg/ml TBHQ as compared to 10 μg/ml TBHQ for L‐arabinose, D‐galactose and maltose and to 15 μg/ml TBHQ for glucose. TBHQ (50 μg/ml) did not inhibit growth of 1.2 × 10 3 cells of S. aureus z‐88, but 30 μg/ml totally inhibited growth of 3.0 × 10 3 cells of S. aureus 100 for 36 hr. TBHQ (100 μg/ml) was bactericidal against the latter strain. TBHQ (10–50 μg/ml) slightly inhibited production of nonheat treated nuclease but had little or no effect on heat treated nuclease of S. aureus z‐88.