The reduced inhibition of bacteria by films prepared with a higher concentration of CO indicates that the binding by CO lowers the amount of LAE diffusing into the liquid medium to inhibit bacteria. Additionally, because the MIC of CO against the three pathogens in TSB is 750 μg/g (Ma et al., 2013), the residual amount of CO in films (no more than 48 mg/cm2, Table 3) may not be sufficiently high to impact the bactericidal activity of LAE at the studied conditions.