TY - JOUR
T1 - Synergistic interaction between wavelength of light and concentration of H2O2 in bactericidal activity of photolysis of H2O2
AU - Toki, Toshihide
AU - Nakamura, Keisuke
AU - Kurauchi, Michiko
AU - Kanno, Taro
AU - Katsuda, Yusuke
AU - Ikai, Hiroyo
AU - Hayashi, Eisei
AU - Egusa, Hiroshi
AU - Sasaki, Keiichi
AU - Niwano, Yoshimi
N1 - Funding Information:
The authors would like to thank Dr. Odashima Y, Dr. Oyamada A and Dr. Yamada Y for their assistance in the experiments. This research was supported by the Ministry of Education, Culture, Sports, Science and Technology, Japan , Grant-in-Aid for Young Scientists (B), 25861820 , 2013.
PY - 2015/3/1
Y1 - 2015/3/1
N2 - The present study aimed to evaluate the interaction between wavelength of light in the range of ultra violet A-visible and concentration of H2O2 in the reaction of photolysis of H2O2 from the point of view of hydroxyl radical (·OH) generation and the bactericidal activity. Light emitting diodes (LEDs) emitting the light at wavelengths of 365, 385, 400 and 465nm were used at an irradiance of 1000mW/cm2. H2O2 was used at the final concentrations of 0, 250, 500, and 1000mM. Quantitative analysis of ·OH generated by the LED irradiation of H2O2 were performed using an electron spin resonance-spin trapping technique. In a bactericidal assay, a bacterial suspension of Staphylococcus aureus prepared in sterile physiological saline was irradiated with the LEDs. The bactericidal activity of each test condition was evaluated by viable counts. When H2O2 was irradiated with the LEDs, ·OH was generated and bacteria were killed dependently on the concentration of H2O2 and the wavelength of LED. The two-way analysis of variance revealed that the wavelength, the H2O2 concentration and their interaction significantly affected the yield of ·OH and the bactericidal activity of the photolysis of H2O2. Therefore, it is suggested that bactericidal activity of photolysis of H2O2 could be enhanced by controlling the wavelength and the concentration of H2O2, which may contributes to shortening the treatment time and/or to reducing the concentration of H2O2.
AB - The present study aimed to evaluate the interaction between wavelength of light in the range of ultra violet A-visible and concentration of H2O2 in the reaction of photolysis of H2O2 from the point of view of hydroxyl radical (·OH) generation and the bactericidal activity. Light emitting diodes (LEDs) emitting the light at wavelengths of 365, 385, 400 and 465nm were used at an irradiance of 1000mW/cm2. H2O2 was used at the final concentrations of 0, 250, 500, and 1000mM. Quantitative analysis of ·OH generated by the LED irradiation of H2O2 were performed using an electron spin resonance-spin trapping technique. In a bactericidal assay, a bacterial suspension of Staphylococcus aureus prepared in sterile physiological saline was irradiated with the LEDs. The bactericidal activity of each test condition was evaluated by viable counts. When H2O2 was irradiated with the LEDs, ·OH was generated and bacteria were killed dependently on the concentration of H2O2 and the wavelength of LED. The two-way analysis of variance revealed that the wavelength, the H2O2 concentration and their interaction significantly affected the yield of ·OH and the bactericidal activity of the photolysis of H2O2. Therefore, it is suggested that bactericidal activity of photolysis of H2O2 could be enhanced by controlling the wavelength and the concentration of H2O2, which may contributes to shortening the treatment time and/or to reducing the concentration of H2O2.
KW - Bactericidal activity
KW - Disinfection
KW - Hydrogen peroxide
KW - Hydroxyl radical
KW - Photolysis
KW - Ultraviolet A
KW - Wavelength
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U2 - 10.1016/j.jbiosc.2014.08.015
DO - 10.1016/j.jbiosc.2014.08.015
M3 - Article
C2 - 25282638
AN - SCOPUS:84922800505
VL - 119
SP - 358
EP - 362
JO - Journal of Bioscience and Bioengineering
JF - Journal of Bioscience and Bioengineering
SN - 1389-1723
IS - 3
ER -