title: The effect of visible light on gold nanoparticles and some bioeffects on environmental fungi.
abstract: The oxidative stress induced by light exposed gold nanoparticles in some microorganism cells was investigated. Gold nanoparticles are currently used in biomedical and pharmaceutical research. For this study citrate-gold nanoparticles were synthesized in alkaline conditions at constant temperature of 85°C under magnetic stirring. Equal volumes of such prepared colloidal solution, were exposed to visible light at different wavelengths for 90min at room temperature. The spectra in the visible and ultraviolet range have revealed an increase in the intensity of the absorption band for gold nanoparticles exposed to light, due to the effect of surface plasmon resonance. Versatility of gold nanoparticles photocatalytic action was shown by means of manipulating wavelengths of incident light, which evidenced differences in the bioeffects induced in cellulolytic fungi - known for their environmental role but also for other applications such as in cosmetics industry. The comparative analysis of fungal response to gold nanoparticle stressors has revealed different enzyme activity and lipid peroxidation when fungi were supplied with gold nanoparticles exposed to different wavelength lights. The activity of catalase and superoxide dismutase were remarkably increased for green light exposure of gold nanoparticles suggesting fungi adaption to increased oxidative stress induced by irradiated particles; increased level of lipid peroxidation was showed by high concentration of malondialdehyde for white light exposed gold particles since antioxidant enzymes were less active.
authors.affiliation: Alexandru Ioan Cuza University, Physics Faculty, 11 Blvd. Carol I, Iasi, 700506, Romania. Electronic address: maria.andries23@gmail.com.
authors.forename: Maria
authors.initials: M
authors.lastname: Andries
authors.affiliation: Alexandru Ioan Cuza University, Physics Faculty, 11 Blvd. Carol I, Iasi, 700506, Romania. Electronic address: daniela.a.pricop@gmail.com.
authors.forename: Daniela
authors.initials: D
authors.lastname: Pricop
authors.affiliation: Alexandru Ioan Cuza University, Biology Faculty, 11 Blvd. Carol I, Iasi, 700506, Romania. Electronic address: iasilacra@yahoo.com.
authors.forename: Lacramioara
authors.initials: L
authors.lastname: Oprica
authors.affiliation: Alexandru Ioan Cuza University, Physics Faculty, 11 Blvd. Carol I, Iasi, 700506, Romania. Electronic address: dorina.creanga@gmail.com.
authors.forename: Dorina-Emilia
authors.initials: DE
authors.lastname: Creanga
authors.affiliation: Alexandru Ioan Cuza University, Physics Faculty, 11 Blvd. Carol I, Iasi, 700506, Romania. Electronic address: iacomi@uaic.ro.
authors.forename: Felicia
authors.initials: F
authors.lastname: Iacomi
mesh_terms: D000222:Adaptation, Physiological / Q000502:physiology; D000975:Antioxidants / Q000378:metabolism; D002374:Catalase / Q000378:metabolism; D005658:Fungi / Q000201:enzymology / Q000378:metabolism*; D006046:Gold / Q000737:chemistry; D008027:Light; D015227:Lipid Peroxidation / Q000502:physiology; D053768:Metal Nanoparticles / Q000737:chemistry*; D018384:Oxidative Stress; D013482:Superoxide Dismutase / Q000378:metabolism; D020349:Surface Plasmon Resonance
chemical_list: D000975:Antioxidants; D006046:Gold; D002374:Catalase; D013482:Superoxide Dismutase
keywords: Antioxidant enzymes; Fungi mycelium; Gold nanoparticles; Oxidative stress