Effect of Certain Antiseptics on the Growth of Escherichia coli in Skim Milk

The present study aims to evaluate the effect of certain antiseptics, such as polyhexamethylene biguanide
(PHMB), polyhexamethylene guanide (PHMG), silver nitrate (AgNO3), and glutamic acid on the behavior of Escherichia coli (ATCC 4229) in skim milk. Briefly, both PHMB and AgNO3 showed significant killing effect against
E. coli, with respect to the higher antibacterial efficacy of PHMB compared to AgNO3. The high killing percentages
and leakage of potassium content exhibited positive direction against E. coli with high antiseptic concentrations up to
certain limits. Using PHMB combined with AgNO3 and PHMG combined with AgNO3 against the growth of E. coli
revealed high killing percentage than using any of these antiseptics separately in skim milk. In the same way, when
PHMB was combined with AgNO3 or PHMG with AgNO3 mixed with glutamic acid, the percentages of survival cells
significantly decreased (P ≤ 0.05) compared to the use of the antiseptics separately with glutamic acid.