Trypticase-Soy Broth (TSB) was inoculated with Streptococcus
diacetilactis, incubated at 21C for 24 hours and centrifuged to remove
the cells. When the spent TSB was inoculated with Staphylococcus
aureus, it allowed 99.8% less growth than fresh TSB. If the spent
TSB were supplemented with 0.08 μg/ml of niacinamide, this inhibition...