Polyamines induce prolonged maintenance of stationary phase turbidity in coagulase-negative Staphylococcus

Microorganisms on the human skin and host form a close and complex community. Abnormal proliferation of certain commensal microorganisms can disrupt this balanced interaction, resulting in the development of skin diseases. Cosmetics is a significant factor affecting the balance of the skin microbiome. We focused a major commensal coagulase-negative Staphylococcus and evaluated the growth effect by five cosmetic ingredients including polyamines. Two polyamines showed notable effects, although others showed no impact effects. They significantly reduced the turbidity during the active growth phase and recovered in the stationary phase. During the death phase, they prolonged the stationary phase turbidity in a concentration-dependent manner, continued by the end of experiments. Our findings could be a previously uncharacterized effect under these experimental conditions.