Antioxidant capacity of edaravone, quercetin, and myricetin involving probabilistic fluctuations using eosin-Y and eosin-B as fluorescent probes in the ORAC assay

• Published in: Journal of photochemistry and photobiology. A, Chemistry. Chemistry., 2025-03, Vol.460, p.116142, Article 116142
• Main Authors: Takatsuka, Miwa, Goto, Satoru, Moritake, Kota, Shimada, Yosuke, Tsuchida, Tomohiro
• Format: Article
• Language: English
• Subjects: Ascorbic acid; BHT; MOPAC2016; Oxygen radical absorbance capacity (ORAC); Probabilistic fluctuations; Trolox
• ISSN: 1010-6030
• DOI: 10.1016/j.jphotochem.2024.116142

[Display omitted] •The oxygen radical absorbance capacity (ORAC) assay using fluorescein (FLH), eosin B, and eosin.•ORAC-FLH results of trolox and ascorbic acid are reproduced in the sigmoidal curve.•Flavonoid, edaravone, and BHT reproduce Gauss function, 3/2-order function, and Weibull’s plot.•ORAC-eosins results of each antioxidant reproduce the Hill’s plot.•Quantum calculations show the cascade chain reaction of FLH to regulate radical reaction. The oxygen radical absorbance capacity (ORAC) assay measures the antioxidant activity of the antioxidants through competitive consumption of peroxyl radicals relative to a fluorescent probe. This study evaluated fluorescein (FLH), eosin Y, and eosin B in ORAC assays using quantum computations. In ORAC-FLH assays, trolox (TRO) and ascorbic acid (ASC) showed fluorescence decay kinetics with a lag time, blocking initial reactions in the quenching cascade. Eosins were more reactive towards peroxyl radicals, making TRO assessment infeasible in ORAC-eosin assays. Quercetin and myricetin exhibited sigmoidal curve drifts proportional to squared and 3/2-ordered incubation times, indicating probabilistic fluorescence decay. Edaravone (EDA) weakly inhibited initial reactions, with accelerated quenching over time. In ORAC-eosin assays, flavonoids and EDA showed indistinguishable behavior due to high eosin reactivity. ORAC-FLH did not significantly assess BHT, though a dose-dependent change in half-life was noted. This study suggests broad applications for ORAC-eosin assays and potential for future comparative research.