The ability of several dietary carotenoids to quench singlet oxygen in a model membrane system (unilamellar DPPC liposomes) has been investigated. Singlet oxygen was generated in both the aqueous and the lipid phase, with quenching by a particular carotenoid independent of the site of generation. However, singlet oxygen quenching is dependent on the carotenoid incorporated; xanthophylls exhibit a marked reduction in efficiency compared to the hydrocarbon carotenoids. Lycopene and beta-carotene exhibit the fastest singlet oxygen quenching rate constants (2.3-2.5 x 10(9)M(-1)s(-1)) with lutein the least efficient (1.1 x 10(8)M(-1)s(-1)). The other carotenoids, astaxanthin and canthaxanthin, are intermediate. Zeaxanthin exhibits anomalous behavior, and singlet oxygen quenching decreases with increasing amounts of zeaxanthin, leading to nonlinear plots for the decay of singlet oxygen with zeaxanthin concentration. Such differences are discussed in terms of carotenoid structure and their influence on the properties of the lipid membrane. The formation of aggregates by the polar carotenoids is also proposed to be of significance in their ability to quench singlet oxygen.
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http://dx.doi.org/10.1016/s0003-9861(03)00014-6 | DOI Listing |
Plant Physiol Biochem
January 2025
Weed Research Laboratory, Nanjing Agricultural University, Nanjing, 210095, People's Republic of China. Electronic address:
The mycotoxin tenuazonic acid (TeA) inhibits photosynthesis and is expected to be developed as a bioherbicide to control Ageratina adenophora that is one of the most serious invasive alien plants in China. New leaves sprouting from A. adenophora at low temperatures (LT) in early spring are less sensitive to TeA compared to those growing in summer.
View Article and Find Full Text PDFPhotochem Photobiol Sci
January 2025
Homi Bhabha National Institute, Training School Complex, Anushaktinagar, Mumbai, 400094, India.
The efficacy of photodynamic treatment (PDT) against deep-seated tumor is hindered by low penetration depth of light as well as hypoxic conditions which prevails in tumor. To overcome this limitation, Near-infrared (NIR) absorbing photosensitizers have been investigated actively. In the present study we evaluated the PDT efficacy of an NIR absorbing chlorophyll derivative 'Cycloimide Purpurin-18 (CIPp-18)' in Human Breast carcinoma (MCF-7) and cervical adenocarcinoma (Hela) cells under normoxic and hypoxic conditions.
View Article and Find Full Text PDFNat Commun
January 2025
State Environmental Protection Key Laboratory of Environmental Health Impact Assessment of Emerging Contaminants, School of Environmental Science and Engineering, Shanghai Jiao Tong University, Shanghai, P.R. China.
In this study, we introduce a highly effective non-metallic iodine single-atom catalyst (SAC), referred to as I-NC, which is strategically confined within a nitrogen-doped carbon (NC) scaffold. This configuration features a distinctive C-I coordination that optimizes the electronic structure of the nitrogen-adjacent carbon sites. As a result, this arrangement enhances electron transfer from peroxymonosulfate (PMS) to the active sites, particularly the electron-deficient carbon.
View Article and Find Full Text PDFACS Appl Bio Mater
January 2025
Department of Chemistry, North Carolina State University, Raleigh, North Carolina 27695, United States.
Ligand-functionalized InP-based quantum dots (QDs) have been developed as an innovative class of nontoxic photosensitizer suitable for antimicrobial applications, aimed at reducing or preventing pathogen transmission from one host to another via high contact surfaces. A hot injection method followed by functionalization via ligand exchange with 9-anthracene carboxylic acid (ACA) yielded the desired core/shell InP/ZnSe/ZnS QDs. Transmission electron microscopy (TEM) revealed these QDs to be uniform in size (∼3.
View Article and Find Full Text PDFACS Appl Mater Interfaces
January 2025
Molecular Diagnostic Center, Key Laboratory of Clinical Cancer Pharmacology and Toxicology Research of Zhejiang Province, Hangzhou First People's Hospital, Hangzhou 310006, China.
The designability and high reactivity of nanotechnology provide strategies for antitumor therapy by regulating the redox state in tumor cells. Here, we synthesize a kind of vanadium dioxide nanoparticle encapsulated in bovine serum albumin and containing disulfide bonds (VSB NPs) for photothermal-enhanced ferroptosis and pyroptosis effects. Mechanism studies show that disulfide bonds can effectively consume overexpressed glutathione (GSH) in the tumor microenvironment, leading to a decrease in glutathione peroxidase 4 (GPX4) activity.
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