Studies on the antibacterial activities of the newly developed Hirokouken hand cream, liquid soap, and hand wash containing Hinokitiol

Abstract

The newly developed hand cream, liquid soap, and hand wash containing Hinokitiol by Hirokouken (Tokyo) were investigated for their antibacterial activities in vitro. These products all contain aluminium chelates of Hinokitiol, which allow them to exert a stable and strong antibacterial activity. Experimentally, a solution containing 50 ppm Hinokitiol mixed with a minium disteareat was found to have the strongest antibacterial activity against MRSA, MSSA, P. aeruginosa, and E. coli. In addition, it was also revealed that hand cream containing a cream base, 0.1% Hinokitiol, and 0.5% alminium disteareat had a statistically significant stronger antibacterial activity than that containing a cream base alone or cream base and 0.1% Hinokitiol. The hand cream containing 0.05% Hinokitiol and 0.186% alminium disteareat, liquid soap containing 0.2% Hinokitiol and 0.294% alminium chloride, and hand wash containing 0.1% Hinokitiol and 0.374% alminium disteareat made by Hirokouken, which are all now commercially available, showed remarkable antibacterial activities as well. These results indicate that these products should thus be useful for both skin care and skin cleaning for such dermatological diseases as atopic dermatitis or infected decubitus.