Avoiding One ‐electron Oxidation of Biomolecules by 3,4‐Dihydroxy‐L‐Phenylalanine (DOPA)
AbstractAbstractIt has been proposed that 3,4-dihydroxy-L-phenylalanine (DOPA) has antioxidant properties and thus, the objective of this work was to evaluate the effect of adding DOPA during the photosensitized oxidation of tyrosine (Tyr), tryptophan (Trp), histidine (His), 2'-deoxyguanosine 5'-monophosphate (dGMP), 2'-deoxyadenosine 5'-monophosphate (dAMP). It was observed that, upon pterin-photosensitized degradation of a given biomolecule in acidic aqueous solutions, the rate of the biomolecule consumption decreases due to the presence of DOPA. Although DOPA deactivates the excited states of pterin (Ptr), biomolecules ...
Source: Photochemistry and Photobiology - September 17, 2022 Category: Science Authors: Jael R. Neyra Recky,
M. Laura D ántola,
Carolina Lorente Tags: Special Issue Research Article Source Type: research
Singlet Oxygen Quenching by Resveratrol Derivatives
Whiletrans-resveratrol and its methylated and partially methylated derivatives do not sensitize the production of singlet oxygen, they are moderately strong quenchers of singlet oxygen. Methylation of the hydroxy groups decreases the total rate of singlet oxygen scavenging (kT) while a protic solvent system results in higherkT values, except for the completely methylated derivative. ABSTRACTWe investigated the singlet oxygen quenching ability of several derivatives oftrans-resveratrol which have been reported to have significant antioxidant ability, including photoprotective activity. We measured the total rate constants o...
Source: Photochemistry and Photobiology - September 16, 2022 Category: Science Authors: Charlotte G. Monsour,
Abegail C. Tadle,
Bliss J. Tafolla ‐Aguirre,
Nidhi Lakshmanan,
Jin Hyeok Yoon,
Rhemrose B. Sabio,
Matthias Selke Tags: Special Issue Research Article Source Type: research
The Glycolysis ‐Derived α‐Dicarbonyl Metabolite Methylglyoxal is a UVA‐Photosensitizer Causing the Photooxidative Elimination of Hacat Keratinocytes with Induction of Oxidative and Proteotoxic Stress Response Gene Expression
AbstractCellular oxidative stress contributes to solar ultraviolet (UV) radiation-induced skin photoaging and photocarcinogenesis. Light-driven electron and energy transfer reactions involving non-DNA chromophores are a major source of reactive oxygen species (ROS) in skin, and the molecular identity of numerous endogenous chromophores acting as UV-photosensitizers has been explored. Methylglyoxal (MG), a glycolytic byproduct bearing a UV-active α-dicarbonyl-chromophore, is generated under metabolic conditions of increased glycolytic flux, associated with posttranslational protein adduction in human tissue. Here, we under...
Source: Photochemistry and Photobiology - September 16, 2022 Category: Science Authors: Lohanna de Faria Lopes,
Jana Jandova,
Rebecca Justiniano,
Jessica Perer,
Maur ício S. Baptista,
Georg T. Wondrak Tags: Special Issue Research Article Source Type: research
In ‐Vitro Effect of 445nm Blue Laser and 660nm Low‐Level Laser on the Quantity and Quality of Human Gingival Fibroblasts
This study aimed to investigate the effect of 445nm blue laser and 660nm low-power laser on the quantity and quality of human gingival fibroblasts in-vitro. In this in-vitro experimental study, 445nm and 660nm lasers were irradiated on the samples six times. After examining the cells on the seventh and fourteenth days, the data were analyzed using ANOVA PASS11 and the post hoc Tukey test. The results showed the positive effect of the 660nm laser on fibroblast proliferation. The viability on the seventh day was the highest in the control group, lowest in the 445nm laser group and highest in the 660nm laser group on the four...
Source: Photochemistry and Photobiology - September 15, 2022 Category: Science Authors: Kimia Hafezi Motlagh,
Arash Azizi,
Nahid Moezzi Ghadim Tags: Method Article Source Type: research
Electronic Characterization of Vis ‐NIR Absorbing Non‐Innocent Ruthenium Oxyquinolate‐Merocyanine Complexes and their Photoacoustic Emission in Aqueous Micellar Solution
AbstractAbstractThe electronic and photophysical properties for a series of ruthenium(II) polypyridyl dyes is presented where a π-accepting 5-(vinyl-cyanine)-8-oxyquinolate class of ligand is incorporated to yield an improved vis-NIR absorption. A combination of computational, UV-vis-NIR absorption, phosphorescence emission and cyclic voltammetry studies are used to probe the influence of these ligands on complex electronic and photophysical properties. To assess their potential as vis-NIR photoacoustic contrast agents select complexes were formulated in PBS buffer/Tween® 20 solvent system. Thep-quinolin-1-ium, 1,3,3-tri...
Source: Photochemistry and Photobiology - September 14, 2022 Category: Science Authors: Peter Catsoulis,
Shengwei Wang,
Chandra Yelleswarapu,
Jonathan Rochford Tags: Special Issue Research Article Source Type: research
