Blue Laser Inhibits Bacterial Growth of Staphylococcus aureus, Escherichia coli, and Pseudomonas aeruginosa

Author(s)

Alves de Sousa, Natanael Teixeira ^[1] ; Santos, Marcos Ferracioli ^[2] ; Gomes, Rosana Caetano ^[1] ; Brandino, Hugo Evangelista ^[1] ; Martinez, Roberto ^[3] ; de Jesus Guirro, Rinaldo Roberto ^{[1, 2]}

Affiliation

^[1] Univ Sao Paulo, Postgrad Program Rehabil & Funct Performance, Dept Biomech Med & Rehabil Locomotor Apparat, Ribeirao Preto Sch Med, BR-14049900 Ribeirao Preto, SP - Brazil

^[2] Univ Sao Paulo, Grad Course Physiotherapy, Dept Biomech Med & Rehabil Locomotor Apparat, Ribeirao Preto Sch Med, BR-14049900 Ribeirao Preto, SP - Brazil

^[3] Univ Sao Paulo, Div Infect Dis, Dept Internal Med, Ribeirao Preto Sch Med, BR-14049900 Ribeirao Preto, SP - Brazil

• Document type: Journal article
• Source: Photomedicine and Laser Surgery; v. 33, n. 5, p. 278-282, MAY 1 2015.
• Web of Science Citations: 9

Abstract

Objective: The purpose of this study was to analyze the influence of blue laser on bacterial growth of the main species that usually colonize cutaneous ulcers, as well as its effect over time following irradiation. Background data: The use of blue laser has been described as an adjuvant therapeutic method to inhibit bacterial growth, but there is no consensus about the best parameters to be used. Methods: Strains of Staphylococcus aureus ATCC 25923, Pseudomonas aeruginosa ATCC 27853, and Escherichia coli ATCC 25922 were suspended in saline solution at a concentration of 1.5x10(3) colony forming units (CFU)/mL. Next, 300 mu L of this suspension was transferred to a microtitulation plate and exposed to a single blue laser irradiation (450 nm) at fluences of 0 (control), 3, 6, 12, 18, and 24 J/cm(2). Each suspension was spread over the surface of a Petri plate before being incubated at 37 degrees C, and counts of CFU were determined after 24 and 48 h. Results: Blue laser inhibited the growth of S. aureus and P. aeruginosa at fluences >6 J/cm(2). On the other hand, E. coli was inhibited at all fluences tested, except at 24 J/cm(2). Conclusions: Blue laser light was capable of inhibiting bacterial growth at low fluences over time, thus presenting no time-dependent effect. (AU)

• FAPESP's process: 11/22170-0 - The effect of low level laser therapy in the spectra of visible and infrared light, diphasic current, high voltage in culture of Staphylococcus aureus, Pseudomonas aeruginosa and Escherichia coli strains in vitro
• Grantee: Rinaldo Roberto de Jesus Guirro
• Support Opportunities: Regular Research Grants
• FAPESP's process: 13/02974-2 - The effect of low level laser therapy in the spectra of visible and infrared light in a culture of Staphylococcus aureus, Pseudomonas aeruginosa and Escherichia coli strains in vitro
• Grantee: Marcos Ferracioli Santos
• Support Opportunities: Scholarships in Brazil - Scientific Initiation