Photosensitized Destruction of Chlorella vulgaris by Methylene Blue or Nuclear Fast Red Combined with Hydrogen Peroxide under Visible Light Irradiation

Abstract

A considerable number of investigations have started to elucidate the essential roles biological agents play in the biodeterioration of stone. Chemical biocides are becoming increasingly banned because of the environmental and health hazards associated with these toxic substances. The present study reports the photodynamic effect of Methylene Blue (MB) and Nuclear Fast Red (NFR) in the presence of hydrogen peroxide (H2O2) on the destruction of the algae Chlorella vulgaris (C. vulgaris) under irradiation with visible light. Illumination of C. vulgaris in the presence of MB or NFR combined with H2O2 results in the decomposition of both the algal species and the photosensitizer. The photodynamic effect was investigated under aerobic and anaerobic conditions. Differences in mechanism type are reported and are dependent on both the presence and the absence of oxygen. The behavior of each photosensitizer leads to a Type II mechanism and a Type I/Type II combination for MB and NFR, respectively, being concluded. This novel combination could be effective for the remediation of biofilm-colonized stone surfaces.

Antimicrobial mechanisms behind photodynamic effect in the presence of hydrogen peroxide

“…, H 2 O 2 would provide more molecules of oxygen for the photoreaction than in water solution and this should increase the amount of ROS produced. Thus, we decided to investigate what would happen with the photoreaction in the presence of a biological substance, since our microbiological experiments and also the literature12–15 agreed that H 2 O 2 gave more microbial PDT killing.…”

Comparison of the Response of Human Embryonic Stem Cells and Their Differentiated Progenies to Oxidative Stress

“…When the cells were 80-90% confluent (2.0Â10 5 to 3.0Â10 5 cells per well), they were exposed to varying levels of oxidative stress by photodynamic treatment. 4,5,11,12 Briefly, this experiment involves irradiating the cells with a diode laser (30 mW, 664 nm) in the presence of 10 mM methylene blue in phosphate-buffered saline (PBS; 1.0 mL per well) for varying durations: 5 min (9 J), 10 min (18 J), 15 min (27 J), 20 min (36 J), 30 min (54 J), and 40 min (72 J). The wavelength of the light source (664 nm) corresponded with the excitation wavelength of methylene blue, and singlet oxygen was generated upon laser irradiation.…”

“…The wavelength of the light source (664 nm) corresponded with the excitation wavelength of methylene blue, and singlet oxygen was generated upon laser irradiation. 11,12 The laser light was delivered using an optical fiber of 400 mm outer diameter (LDCU=6130, Power Technology Inc., Little Rock, AR, USA). The bare optical fiber tip (output power at the tip was 30 mW) was used to illuminate the cells.…”

Influence of hydrogen peroxide or gold nanoparticles in protoporphyrin IX mediated antimicrobial photodynamic therapy on Staphylococcus aureus

“…It is reported that, H 2 O 2 can be combined successfully in APDT to enhance the effecttiveness of the PS (McCullagh and Robertson, 2006). Garcez et al (2011) studied the antimicrobial photodynamic effect of methylene blue (MB) in the presence of H 2 O 2 to kill S. aureus, Escherichia coli and Candida albicans.…”