cis-Urocanic acid (cis-UCA), formed from trans-urocanic acid (trans-UCA) by photoisomerization, has been shown to mimic suppressive effects of UV on the immune system. It is our hypothesis that UCA oxidation products in the skin play a role in the process of immunosuppression. Recently, both UCA isomers were found to be good hydroxyl radical scavengers and in this context we investigated the formation of products resulting from the interaction of hydroxyl radicals with UCA. Hydroxyl radicals were generated by (1) UV/H(2)O(2) (photooxidation), (2) ferrous ions/H(2)O(2) (Fenton oxidation) and (3) cupric ions/ascorbic acid. Oxidation products were identified by spectrometric methods and assessed by reversed-phase HPLC analysis. The photooxidation of UCA was induced by UV-B and UV-C, but not by UV-A radiation. Photooxidation and Fenton oxidation of trans-UCA, as well as of cis-UCA yielded comparable chromatographic patterns of UCA oxidation products. Several of the formed products were identified. The formation of three identified imidazoles was shown in UV-B exposed corneal layer samples, derived from human skin.
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http://dx.doi.org/10.1016/s0304-4165(01)00139-8 | DOI Listing |
Plant Physiol Biochem
January 2025
Botany Department, Federal University of Pelotas, Capão Do Leão, RS, 96160-000, Brazil.
Waterlogging is a significant stressor for crops, particularly in lowland regions where soil conditions exacerbate the problem. Waterlogged roots experience hypoxia, disrupting oxidative phosphorylation and triggering metabolic reorganization to sustain energy production. Here, we investigated the metabolic aspects that differentiate two soybean sister lines contrasting for waterlogging tolerance.
View Article and Find Full Text PDFJ Food Sci
January 2025
Nutrition Research Center, Department of Food Science and Technology, Faculty of Nutrition and Food Sciences, Tabriz University of Medical Sciences, Tabriz, Iran.
Alternatives to nonbiodegradable synthetic plastics for food packaging include films made from biopolymers that are nontoxic and environment-friendly. In this study, carnauba wax (CW) and nitrogen-doped graphene quantum dots (NG) as functional additives were utilized in the production of pectin/gelatin (PG) film. NG was synthesized through the microwave method, using acetic acid as the carbon source, giving size, and zeta potential of 1.
View Article and Find Full Text PDFJ Food Sci
January 2025
Department of Agricultural and Biological Engineering, University of Florida, Gainesville, Florida, USA.
Dry ice is one of the world's most in-demand commodities for cold-chain distribution of temperature-sensitive products. It offers an effective cooling solution without requiring mechanical refrigeration or specialized equipment. Dry ice is commonly produced as pellets and blocks.
View Article and Find Full Text PDFEnviron Sci Pollut Res Int
January 2025
Department of Civil Engineering, National Institute of Technology Andhra Pradesh, Tadepalligudem, India.
Plastics are widely used across various applications from packing to commercial products. Once discarded, they were subjected to environmental stresses, causing them to degrade into microplastics (MPs). These small, invisible pollutants pose a significant threat to aquatic ecosystems, gradually compromising the resilience and vitality of the natural environment.
View Article and Find Full Text PDFPharmacol Rep
January 2025
Center for Global Health Research, Saveetha Medical College and Hospitals, Saveetha Institute of Medical and Technical Sciences, Saveetha University, Chennai, India.
Cardiovascular illnesses are multifactorial disorders and represent the primary reasons for death worldwide, according to the World Health Organization. As a signaling molecule, nitric oxide (NO) is extremely permeable across cellular membranes owing to its unique molecular features, like its small molecular size, lipophilicity, and free radical properties. Some of the biological effects of NO are vasodilation, inhibition in the growth of vascular smooth muscle cells, and functional regulation of cardiac cells.
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