Table 3. Antibacterial activity of casein hydrolysate fractions with Protamex®

Sample Degree of inhibition of fractions1) S. enterica
B. cereus E. coli S. aureus
PC +
CPP + ++ ++ +
F3 ++ +++ +++ ++
F4 +++ ++ ++ ++
F5 ++ +++ ++ +
F6 ++ ++ + ++
F7 ++ ++ ++ ++
All samples protein concentration were 200 μg/mL.
All values were mean±SD of triplicates.
The diameters of the clear zone of inhibition were as follows: +, 1.0≤diameter≤1.5; ++, 1.5≤diameter≤2.0; +++, diameter>2.0.
PC, positive control (0.25 N HCl); CPP, casein phosphopeptide.