Microbiological evaluation of disinfectants by microplate method and clinical study

• Published in: Japanese Journal of Chemotherapy Vol. 49; no. 1; pp. 36 - 44
• Main Authors: Yoshida, Masaki, Shiba, Kohya, Aizawa, Kumiko
• Format: Journal Article
• Language: Japanese
• Published: Japanese Society of Chemotherapy 2001; 公益社団法人 日本化学療法学会
• Subjects: マイクロプレート; 付着菌; 殺菌作用; 毒薬; 浮遊菌
• ISSN: 1340-7007; 1884-5886
• DOI: 10.11250/chemotherapy1995.49.36

The bactricidal activity of benzalconium chloride (BAC), chlorhexidine (CHG). popidone iodine (PVPI) and alkyldiaminoethylglycine hydrochloride (AEG) on methicillin-resistant Staphylococcus aureus (MRSA, 10 clinical isolates) and Psudomonas aeruginosa (6 clinical isolates) was evaluated by the microplate method. And the effect of organic substances (3% yeast) on the bactericidal activity of these disinfectants was examined. All disinfectants showed excellent bactericidal activity on floating MRSA and P. aeruginosa. The bactricidal activity of PVP-I on MRSA and that of CHG on MRSA and P. aeruginosa were weaker than other disinfectants in lower concentrations. All of four disinfectants showed weaker bactericidal activity on adhered bacteria than on floating bacteria. Against adhered MRSA, the bactericidal activity of AEG and BAC decreased to 20-30%, and the activity of PVP-I and CHG to 30-50% of the activity against floating bacteria. As to P. aeruginosa, the bactericidal activity against adhered bacteria was weaker than that against floating bacteria. The bactreicidal activity of PVP-I and AEG in the presence of 3% yeast was decreased to 30% of the activity without yeast. In the clinical study, PVP-I had excellent eradication rate. The most common survival bacteria was Bacillus.