Comparative Effects of Food Preservatives on the Production of Staphylococcal Enterotoxin I from Staphylococcus aureus Isolate

Figure 1

Viable plate count of penicillin-resistant S. aureus strain H4 treated with different food preservatives. (a) 2 × 10⁵ CFU S. aureus H4 was inoculated in 250 mL TSB medium supplemented with 0.15 g/L (1x), 0.075 g/L (1/2x), or 0.0375 g/L (1/4x) sodium nitrite; 0.25 g/L (1x), 0.125 g/L (1/2x), or 0.0625 g/L (1/4x) polylysine; 6 g/L (1x), 3 g/L (1/2x), or 1.5 g/L (1/4x) chitosan; and 0.8 g/L (1x), 0.4 g/L (1/2x), or 0.2 g/L (1/4x) tea catechin, respectively. After incubation at 37°C for 24 hours, 1 mL cell suspension was collected for viable plate count. (b) 2 × 10⁵ CFU S. aureus H4 was inoculated in 250 mL TSB medium supplemented with 0.15 g/L sodium nitrite, 0.25 g/L polylysine, 6 g/L chitosan, or 0.4 g/L tea catechin for 12, 24, and 48 hours, respectively. Data were the mean ± SEM of three independent experiments ().

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