Several yeast species are able to synthesize and accumulate UV-radiation-absorbing mycosporine metabolites that are of unclear physiological function. In this work we analyzed the relationship between mycosporine-glutaminol glucoside (MGG) production, cell survival after UVB irradiation, and formation of cyclobutane pyrimidine dimers (CPDs). We also assessed the photostability and singlet oxygen quenching activity of MGG. A set of nine isolates of the basidiomycetous yeast Cryptococcus steppossus cultured in both dark and light conditions was used for the studies. Survival of the UVB-irradiated isolates and MGG concentration had a linear relationship when the concentration was over 2.5 mg g(-1). CPD accumulation and MGG accumulation were inversely related. MGG in aqueous solution was photostable with a photodecomposition quantum yield of 1.16 × 10(-5). MGG quenching of singlet oxygen was also observed, and the rate constant for the process in D(2)O was 5.9 × 10(7) M(-1) s(-1). Our results support the idea that MGG plays an important role as a UVB photoprotective metabolite in yeasts by protecting against direct damage on DNA and probably against indirect damage by singlet oxygen quenching.
Download full-text PDF |
Source |
---|---|
http://dx.doi.org/10.1667/rr2245.1 | DOI Listing |
Environ Sci Process Impacts
January 2025
Key Laboratory of Industrial Ecology and Environmental Engineering (Ministry of Education), School of Environmental Science and Technology, Dalian University of Technology, Dalian, 116024, China.
Environmentally persistent free radicals (EPFRs) have been widely detected in polycyclic aromatic hydrocarbon (PAH)-contaminated soils, but the activation of persulfate by inherent EPFRs in PAH-contaminated soil for the transformation of PAHs remains unclear. In the present study, benzo[]pyrene (B[]P) was selected as a representative PAH and its transformation in a persulfate/B[]P-contaminated soil system was studied without the addition of any other activator. Results indicated that EPFRs in the soil activated persulfate to produce reactive oxygen species (ROS) and degraded B[]P.
View Article and Find Full Text PDFInt J Nanomedicine
January 2025
Department of Biomedical Sciences and Engineering, National Central University, Taoyuan City, Taiwan, Republic of China.
Background: Cancer treatments are still limited by various challenges, such as off-target drug delivery, posttreatment inflammation, and the hypoxic conditions in the tumor microenvironment; thus, the development of effective therapeutics remains highly desirable. Exosomes are extracellular vesicles with a size of 30-200 nm that have been widely applied as drug carriers over the last decade. In this study, melanoma-derived exosomes were used to develop a perfluorocarbon (PFC) drug nanocarriers loaded with indocyanine green (ICG) and camptothecin (CPT) (ICFESs) for targeted cancer photochemotherapy.
View Article and Find Full Text PDFNanoscale Adv
January 2025
Grupo de Física Nuclear, EMFTEL & IPARCOS, Universidad Complutense de Madrid Pl. de las Ciencias, 1, Moncloa-Aravaca Madrid Spain
Radiation therapy is a common cancer treatment but often damages surrounding healthy tissues, leading to unwanted side effects. Despite technological advancements aimed at improving targeting, minimizing exposure to normal cells remains a major challenge. High-Z nanoparticles, such as gold nanoparticles (AuNPs), are being explored as nano-radiosensitizers to enhance cancer treatment through physical, biological, and chemical mechanisms.
View Article and Find Full Text PDFACS Appl Mater Interfaces
January 2025
Graduate School of Environmental Science, Hokkaido University, N10, W5, Sapporo 060-0810, Japan.
We present a versatile approach to designing and utilizing high-performance nonmetal near-infrared (NIR) organic photocatalysts based on aromatic sulfones. Current NIR photocatalysts are mainly metal complexes and inorganic materials, while the few reported nonmetal organic NIR photocatalysts primarily use photosensitization to produce active species such as singlet oxygen. Our sulfone-rosamine-based redox photocatalyst demonstrates exceptional capabilities, including high ability for metal-free photo-oxidative bromination, intrinsically oxygen-independent redox reactions, and remarkable photostability with a turnover number (TON) exceeding 2800.
View Article and Find Full Text PDFSmall
January 2025
College of Chemical Engineering, Zhejiang University of Technology, Hangzhou, 310014, P. R. China.
Developing single-particle nanocomposite with aqueous-phase orthogonal multicolor phosphorescence or multimodal luminescence holds great significance for optical coding, anti-counterfeiting encryption, bioimaging, and biosensing. However, it faces challenges such as a limited range of emission wavelengths and difficulties in controlling the synthesis process. In this work, a conjugate structure manipulation integrated luminophor confinement strategy is proposed to prepare carbon dots@upconversion nanoparticles (CDs@UCNPs) featuring aqueous-phase orthogonal multicolor room-temperature phosphorescence-upconversion luminescence (RTP-UCL) through wet-chemical synthetic methods.
View Article and Find Full Text PDFEnter search terms and have AI summaries delivered each week - change queries or unsubscribe any time!