In the present study we explore the efficacy of caffeine in dissociating the ethidium (Et) molecule, a model DNA-intercalator as well as a potential mutagen, from nanometer sized micelles of various charges. Steady-state and picosecond-resolved spectroscopic studies on the detachment of Et from various biomimicking micelles of different charges (cationic hexadecyltrimethylammonium bromide (CTAB), neutral (polar) Triton X-100 (TX-100), and anionic sodium dodecyl sulfate (SDS)) reveal the specificity of the caffeine molecule for carrying out such dissociation. The picosecond-resolved Förster resonance energy transfer (FRET) studies between a DNA minor groove binder dye Hoeschst 33258 (H258, donor) and Et (acceptor) have been employed to investigate the alteration in their association in the presence of caffeine at the molecular level. Analysis of our experimental results employing both the generalized and the extended version of the well-known "Infelta-Tachiya model" vividly illustrates how the distribution of Et along with the equilibrium constant of its solubilization in the micelle changes in the presence of caffeine in aqueous solution. Finally, our fluorescence micrographs of squamous epithelial cells validate the alteration of FRET efficiency between the donor and the acceptor due to the release of the latter in the presence of caffeine.
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http://dx.doi.org/10.1021/jp302734e | DOI Listing |
Food Res Int
February 2025
Key Laboratory of Tea Biology and Resources Utilization, Ministry of Agriculture, National Center for Tea Improvement, Tea Research Institute Chinese Academy of Agricultural Sciences (TRICAAS), Hangzhou 310008, China. Electronic address:
Tea is a widely consumed beverage worldwide due to its rich secondary metabolites. Gallotanin: 1-O-galloyl-6-O-luteoyl-α-D-glucose (GLAG) has strong antioxidant activity and good resistance to a wide range of bacteria and malaria. Despite its potential, there have been few reports on GLAG in plants.
View Article and Find Full Text PDFSci Total Environ
January 2025
Department of Chemistry, Université de Sherbrooke, Sherbrooke, QC, Canada; Université de Sherbrooke Water Research Group (GREAUS), Université de Sherbrooke, Sherbrooke, QC, Canada. Electronic address:
In Canada studies on the presence of trace organic contaminants (TrOCs) such as pharmaceuticals, personal care products, pesticides and flame retardants in lakes have primarily focused on the water column at localized scales. To address this gap, the occurrence of 44 TrOCs, representative of various types of human activities, was investigated in surface sediments (0-2 cm) from 193 lakes across Canada. A total of 28 targeted TrOCs were detected, with 99.
View Article and Find Full Text PDFMar Pollut Bull
January 2025
Institute of Oceanology of the Polish Academy of Sciences, Powstańców Warszawy 55, 81-712 Sopot, Poland. Electronic address:
This study examines pharmaceutical residues in the seawater of west Spitsbergen fjords, using indicator compounds that represent different types of medications with various therapeutic uses (sulfamethoxazole, trimethoprim, carbamazepine, diclofenac, and caffeine). Over three years (summer 2018-2021), trimethoprim, carbamazepine, diclofenac, and caffeine were detected in the investigated fjords (Hornsund, Adventfjorden, Grønnfjorden, Isfjorden, and Kongsfjorden), with diclofenac and caffeine being the most common. Sulfamethoxazole was below the limit of detection in all samples.
View Article and Find Full Text PDFEnviron Geochem Health
January 2025
School of Civil Engineering, Vellore Institute of Technology, Tamil Nadu, Vellore, 632014, India.
Urban environments are heavily influenced by various activities, leading to contamination of water sources by emerging contaminants (ECs). Among these, caffeine (CAF) and N, N-diethyl-meta-toluamide (DEET) are notable ECs frequently found in domestic sewage due to human activities. Despite extensive research on emerging contaminants, limited studies have focused on the seasonal variations, human health and ecological risks of CAF and DEET in urban groundwater, particularly in Indian cities.
View Article and Find Full Text PDFEcotoxicol Environ Saf
January 2025
Department of Ecology and Coastal Management, Institute of Marine Sciences of Andalusia (ICMAN - CSIC), Puerto Real 11519, Spain. Electronic address:
The presence of pharmaceuticals in the aquatic environment is increasing due to their growing use for human health. Although most studies are based on short exposures to these contaminants, the present study has emerged from the need to study pharmaceuticals in aquatic organisms over a long-term exposure to understand any multi-generational chronic effects and alterations regarding habitat selection. Therefore, this study shows: (1) the ability of Daphnia magna to colonize environments contaminated with caffeine, ibuprofen and fluoxetine, and (2) the effect of these pharmaceuticals on reproduction and habitat selection (under two scenarios: with and without food) after a long-term exposure period of three generations.
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