Biol. Pharm. Bull., 30(3),585-587, March 2007

Notes

Susceptibilities of Methicillin-Resistant Staphylococcus aureus Isolates to Seven Biocides

Koji NARUI,^a Mitsuo TAKANO,^b Norihisa NOGUCHI,^*,a and Masanori SASATSU^a

^a Department of Microbiology, School of Pharmacy, Tokyo University of Pharmacy and Life Science; 1432-1 Horinouchi, Hachioji, Tokyo 192-0392, Japan: and ^b Department of Pharmacy, Hokushin General Hospital; 1-5-63 Nishi, Nakano, Nagano 383-8505, Japan. * To whom correspondence should be addressed. e-mail: noguchin@ps.toyaku.ac.jp

Minimum bactericidal concentrations (MBCs) of seven biocides for 42 methicillin-resistant Staphylococcus aureus (MRSA) isolates at 5, 30, or 180 min, for hand scrubs or soaks, isolated in 2003 in Japan were determined. The MBC values of glutaraldehyde, povidone iodine, and ethanol were lower than the user concentrations in all exposure times. However, at 5 min exposure of sodium hypochlorite, benzalkonium chloride, alkyldiaminoethylglycine hydrochloride, and chlorhexidine digluconate some strains showed higher MBC values than the user concentrations. These results indicated the possibility that MRSA survived under proper user concentration conditions and exposure time.

Key words methicillin-resistant Staphylococcus aureus; minimum bactericidal concentration; biocide; user concentration; exposure time