Discrepancies in the Enumeration of Escherichia coli1

摘要: Stationary-phase cells of Escherichia coli were enumerated by the pour plate method on Trypticase soy agar containing 0.3% yeast extract (TSYA), violet red-bile agar, and desoxycholate-lactose most-probable-number in Brilliant Green-bile broth lauryl sulfate broth. Maximum counts assumed to be those TSYA. In general, numbers detected lower with selective solid media higher liquid media. Inhibitory effects, especially varied strains E. coli. The detection was partly due stress induced some temperature melted used method. These apparently failed repair form colonies Improved achieved using 1% nonfat milk solids, peptone, or MgSO(4).7H(2)O dilution blanks. Higher effected surface plating surface-overlay cells. appeared superior for direct enumeration foods.