Exploring antioxidant potential of flavonoid derivatives after ESIPT process provides a theoretical basis for discovering compounds with higher antioxidant capacity. In this work, employing the density functional theory (DFT) and time-dependent density functional theory (TD-DFT) methods, the antioxidant potential of two citrus-derived naringenin flavonoids after ESIPT process is explored. Based on studies of ESIPT process including IMHB intensity variations, potential energy curves, and transition state, these molecules exist only in enol and keto⁎ forms due to ultra-fast ESIPT. The HOMOs are utilized to explore electron-donating capacity, demonstrating that the molecules in keto⁎ form is stronger than that in enol form. Furthermore, the atomic dipole moment corrected Hirshfeld population (ADCH) and Fukui functions indicate that the sites attacked by the electrophilic free radical of the two molecules in the keto⁎ form are O3 and O5\' respectively, and both are more active than in the enol form. Overall, a comprehensive consideration of the ESIPT process and antioxidant potential of flavonoid derivatives will facilitate the exploration and design of substances with higher antioxidant capacity.

Hybrid crude palm oil (HCPO) HIE OxG is notable for its abundance of carotenoids, tocopherols, and tocotrienols. Investigating cellular antioxidant activity (CAA) and the non-cytotoxicity of oil nanoparticles is crucial for understanding the behavior of these phytochemicals in biological systems and ensuring the safety of products. Nanoparticles of HCPO, encapsulated with jackfruit by-products were produced and characterized for CAA and cytotoxicity in Caco-2 cells. The nanoparticles exhibited nanoscale diameters (<250 nm), uniform distribution and stability (polydispersity index < 0.25; zeta potential JSF-NP -12.46 ± 0.15 mV and JAF-NP -13.73 ± 1.28 mV). JSF-NP and JAF-NP demonstrated superior CAA compared to the free HCPO across all concentrations, without inducing cytotoxic effects on differentiated Caco-2 cells. This study underscores the importance of investigating the CAA of edible oil nanoparticles, with non-cytotoxicity indicating biological safety and the potential to safeguard intestinal epithelial cells. Thus, JSF-NP and JAF-NP emerge as promising delivery systems for future HCPO applications.

A comparative study of volatile constituents, antioxidant activity, and molecular docking was conducted between essential oils from Mentha longifolia L., Mentha spicata L., and Origanum majorana L., widely cultivated in Madinah. The investigation of volatile oils extracted by hydrodistillation was performed using Gas Chromatography-Mass Spectrometry (GC-MS). A total number of 29, 42, and 29 components were identified in M. longifolia, M. spicata, and O. majorana representing, respectively, 95.91, 94.62, and 98.42, of the total oils. Pulegone (38.42%), 1,8-cineole (15.60%), menthone (13.20%), and isopulegone (9.81%) were the dominant compounds in M. longifolia oil; carvone (35.14%), limonene (27.11%), germacrene D (4.73%), and β-caryophyllene (3.02%) were dominant in M. spicata oil; terpin-4-ol (42.47%), trans-sabinene hydrate (8.52%), γ-terpinene (7.90%), α-terpineol (7.38%), linalool (6.35%), α-terpinene (5.42%), and cis-sabinene hydrate (3.14%) were dominant in O. majorana oil. The antioxidant activity, assessed using DPPH free radical-scavenging and ABTS assays, was found to be the highest in O. majorana volatile oil, followed by M. spicata and M. longifolia, which is consistent with the differences in total phenolic content and volatile constituents identified in investigated oils. In the same context, molecular docking of the main identified volatiles on NADPH oxidase showed a higher binding affinity for cis-verbenyl acetate, followed by β-elemene and linalool, compared to the control (dextromethorphan). These results prove significant antioxidant abilities of the investigated oils, which may be considered for further analyses concerning the control of oxidative stress, as well as for their use as possible antioxidant agents in the pharmaceutical industry.

The evaluation of antioxidant compounds that counteract the mutagenic effects caused by the direct action of reactive oxygen species on DNA molecule is of considerable interest. Therefore, a series of 2,3-substituted quinazolinone derivatives (Q1-Q8) were investigated by different assays, and the relationship between their biological properties and chemical structure was examined. Genotoxicity and the potential DNA-protective effects of Q1-Q8 were evaluated by comet assay and DNA topology assay. Antioxidant activity was examined by DPPH-radical-scavenging, reducing-power, and total antioxidant status (TAS) assays. The cytotoxic effect of compounds was assessed in human renal epithelial cells (TH-1) and renal carcinoma cells (Caki-1) by MTT assay. Analysis of the structure-activity relationship disclosed significant differences in the activity depending on the substitution pattern. Derivatives Q5-Q8, bearing electron-donating moieties, were the most potent members of this series. Compounds were not genotoxic and considerably decreased the levels of DNA lesions induced by oxidants (H2O2, Fe2+ ions). Furthermore, compounds exhibited higher cytotoxicity in Caki-1 compared to that in TH-1 cells. Substantial antioxidant effect and DNA-protectivity along with the absence of genotoxicity suggested that the studied quinazolinones might represent potential model structures for the development of pharmacologically active agents.

The multi-target activity of curcumin makes it a promising pharmacological lead for structural modifications focused on the preparation of new better therapeutics with improved bioavailability. A possible modification is to \"decompose\" the parent curcumin structure into constituent units and to build up curcumin analogues with biphenyl structural moiety. The antioxidant properties of the so-called \"monomers\" (m1-m3) and \"dimers\" (d1-d3) are studied experimentally and computationally. Their protective effects as chain-breaking antioxidants are investigated for the individual compounds and in binary/ternary compositions with α-tocopherol (TOH) and ascorbyl palmitate (AscPH). All monomers manifest significant synergism up to 70% in mixtures with TOH. Synergistic effects are found for the ternary compositions of monomeric analogues upon addition to the binary mixture of standard antioxidants (TOH + AscPH). Dimers with biphenyl skeleton manifest a lower potential in compositions under lipid oxidation conditions. DFT computations provide a detailed insight into the structure and antiradical properties of the curcumin analogues and standard antioxidants. PRACTICAL APPLICATIONS: Bioactive compounds in the diet play a crucial role in the prevention of numerous diseases in whose pathogenesis oxidative stress is well known to be involved. Therefore, enhancement of the antioxidant status of the biological target is often helpful. Two of the monomers studied are considered leading agents in the treatment or prophylaxis of smooth muscle disorders and are useful in the maintenance of the normal gut function- as a calmative for the gut and to ease upset stomach. We hypothesized that the presence of a biphenyl scaffold in the parent molecular structure can enhance the biological activity. Equimolar mixtures of TOH with studied compounds have potential application in food chemistry and medicine. A composition comprising the active agent and additional components (strong conventional antioxidants) may be administered in foodstuffs, as a food supplement, beverage supplement, or as a pharmaceutical composition.

This study is aimed to investigate the aroma composition, phenolic acid, antioxidant activities and computational analysis of essential oils of five different parts of A. columnaris (G. Forst.) Hook. from India. The essential oils were obtained from the fresh root, stem, leaves, bark, and branch of A. columnaris by hydro-distillation using a Clevenger apparatus: the volatile composition was examined by GC-MS; the phenolic acid quantification by RP-HPLC-DAD and the estimation of antioxidant potential by TAC, FRAP, CUPRAC, MCA, DRSC, and NOSC assays. Total 136 chemical compounds i.e. root-60, stem-55, leaves-50, bark-55 and branch-42 were identified in essential oils by GC-MS and major constituents were β-pinene, terpinolene, 2-nonanone, pinocarveol, trans-verbenol, dihydrocarvone, dodecane, thymol, isolongifolene, α-copaene, α-gurjunene, β-caryophyllene, isoledene, γ-muurolene, γ-cadinene, etc. The five phenolic acid contents were determined by RP-HPLC-DAD with AR: 91-99%, LOD: 0.010269-0.119857 mg/g and LOQ: 0.039553-0.003388 mg/g. The Density Functional Theory (DFT) study was carried out on the main phytochemicals present in essential oils of A. columnaris in a manner to support the experimental results and give detailed of antioxidants and reactivity parameters. The results suggested that the essential oils of A. columnaris have high antioxidant potential due to the presence of phenolic acids and aroma compositions.

Compared to plants, nowadays mushrooms attract more attention as functional foods, due to a number of advantages in manipulating them. This study aimed to screen the chemical composition (fatty acids and phenolics) and antioxidant potential (OH•, 2,2-diphenyl-1-picrylhydrazyl (DPPH•) and ferric reducing ability of plasma (FRAP)) of two edible mushrooms, Coprinus comatus and Coprinellus truncorum, collected from nature and submerged cultivation. Partial least square regression analysis has pointed out the importance of some fatty acids-more precisely, unsaturated fatty acids (UFAs) followed by fatty acids possessing both short (C6:0 and C8:0) and long (C23:0 and C24:0) saturated chains-and phenolic compounds (such as protocatechuic acid, daidzein, p-hydroxybenzoic acid, genistein and vanillic acid) for promising anti-OH•, FRAP and anti-DPPH• activities, respectively. However, other fatty acids (C16:0, C18:0 and C18:3n3) along with the flavonol isorhamnetin are actually suspected to negatively affect (by acting pro-oxidative) the aforementioned parameters, respectively. Taken together, design of new food supplements targeting oxidative stress might be predominantly based on the various UFAs combinations (C18:2n6, C20:1, C20:2, C20:4n6, C22:2, C22:1n9, etc.), particularly if OH• is suspected to play an important role.

The strategy of investigating the antioxidant potential of flavonols through the explicit modeling of chemical reactions (initiated to be employed in a previous work from our group) was taken further in this work. Therefore, a theoretical investigation on the reaction between fisetin and 2,2-diphenyl-1-picrylhydrazyl (DPPH) is presented. All the computations were performed using the density functional theory with the B3LYP functional along with the 6-31G(d,p) basis set. Structural, energetic quantities (ΔG and ΔG++), and reaction rates were probed in order to provide information on the antioxidant activity and to explore the contributions of each hydroxyl group to the referred property. According to the results obtained for the thermodynamic properties, fisetin presents antioxidant potential similar to quercetin (behavior that is also observed experimentally). In addition, the order of contribution of each OH group to the antioxidant potential was found to be 4\'-ArOH (the most contributor, presenting ΔG = -5.17 kcal/mol) → 3\'-ArOH (ΔG = -3.35 kcal/mol) → 3-ArOH (ΔG = -1.64 kcal/mol) → 7-ArOH (ΔG = 7.72 kcal/mol). These observations are in consistent agreement with the outcomes of other computational investigations performed using bond dissociation enthalpies (BDEs) as descriptors for the antioxidant activity. Therefore, the methodology employed in this work can be used as an alternative for probing antioxidant potential of compounds derived from fisetin. Graphical Abstract Illustrative scheme of the PES mapping in terms of hydrogen atom transfer from fisetin 3-ArOH to the nitrogen centered DPPH.

In this work, we present a computational study on the antioxidant potential of myricetin 3-O-α-L-rhamnopyranoside (Compound M3) and myricetin 4\'-O-α-L-rhamnopyranoside (Compound M4\'). Structural parameters, bond dissociation enthalpies (BDEs), ionization potentials (IPs), proton dissociation enthalpies (PDEs), proton affinities (PAs), and electron transfer enthalpies (ETEs), which are properties connected with different mechanisms related to antioxidant activity, were determined using density functional theory (DFT) with B3LYP, LC-ωPBE, M06-2X, and BMK functionals along with the 6-311G(d,p) and 6-311+G(d,p) basis sets in the gas phase, water, and pentylethanoate. The values obtained were compared with results previously available in the literature for myricetin (the parent molecule and a well-known antioxidant) and myricetin 3,4\'-di-O-α-L-rhamnopyranoside (Compound M3,4\'). As the BDEs are considerably lower than the IPs, the HAT mechanism is preferred over SET for the compounds M3 and M4\'. The present study indicates Compound M3 as having its lowest bond dissociation enthalpy from the several different OH groups with similar value to the lowest for myricetin (74.72 kcal/mol versus 74.8 kcal/mol, respectively, at the B3LYP/6-311G(d,p) level of theory in the gas phase) and, thus, presenting antioxidant potential as good as its parent molecule. On the other hand, Compound M4\' presented 78.97 kcal/mol as the lowest BDE at the B3LYP/6-311G(d,p) level of theory in the gas phase, that is very close to the 78.34 kcal/mol computed using the same approach for Compound M3,4\'. Therefore, the present investigation indicated Compound M4\' as being a slightly inferior antioxidant (with antioxidant potential comparable to Compound M3,4\') than Compound M3. In addition, the inclusion of the sugar moiety studied here in the position 4\'-ArOH of myricetin seems to have a more marked impact (downward) on the antioxidant activity than the glycosylation in the position 3-ArOH.

Tyrosyl oleate (TO), synthesized using oleic acid and tyrosol, was added to the original receipt of tarallini, to evaluate its antioxidant effectiveness. Lipid oxidation in control sample and samples with 1%, 4%, and 7% of TO at different storage times (0, 15, 30, 37, and 45 days) was evaluated. Accelerated oxidation analysis showed that the control sample took more than four times to complete the oxidation compared tarallini with TO. The control sample and tarallini with 1% of TO exceeded the peroxide value limit after 30 days of storage and the other two final products after 45 days. The control sample registered a oxidized fatty acid concentration higher than all the samples formulated with TO. The concentration of volatile compounds from lipid oxidation in tarallini with TO showed a lower concentration than the control sample. All the determinations carried out confirm, for the first time, that TO can counteract lipid oxidation in a real lipid system.