Search Results (178)

Understanding the interactions between carbon quantum dots (CDs) and promising food preservatives (FPs), like pyrogallol (PG), benzoic acid (BA), and gallic acid (GA), is highly relevant. This knowledge is crucial for designing CD-based sensors capable of determining the safe levels of these molecules in food and beverages. Additionally, such sensors could be exploited in the development of sustainable, intelligent packaging that controls food shelf life. Based on those considerations, in this study, we post-functionalized blue-emitting CDs, prepared according to a synthetic approach previously developed, with the FP molecules PG, BA, and GA to obtain CD-(FP) systems. UV-vis absorption and FTIR spectroscopy confirmed the presence of the FP molecules on the CD surface. The appearance of a new vibrational band at 1196 cm⁻¹ in the FTIR spectra of all CD-(FP) systems suggested that the three FP molecules interact with the CD surface via electronic interactions between the aromatic and delocalized electron systems. Further electrochemical analyses of the CD-(PG) and CD-(GA) systems show that the interactions between PG and GA benzene rings and CDs prevent their oxidation to the corresponding quinone forms. Full article

This study introduces a novel nucleic acid testing (NAT) protocol that integrates rapid deoxyribonucleic acid (DNA) extraction, isothermal amplification, and visual detection to enable efficient analysis of opportunistic pathogens. Polyethylenimine-functionalized iron oxide (PEI-Fe₃O₄) nanoparticles were prepared by combining PEI, acting as a stabilizing agent, with iron salt, which was utilized as the metal ion precursor by the ultrasonication-assisted co-precipitation method, and characterized for structural, optical, and magnetic properties. PEI-Fe₃O₄ exhibited cationic and anionic behavior in response to pH variations, enhancing adaptability for DNA binding and release. PEI-Fe₃O₄ enabled efficient extraction of E. faecium DNA within 10 min at 40 °C, yielding 17.4 ng/µL and achieving an extraction efficiency of ~59% compared to a commercial kit (29.5 ng/µL). The extracted DNA was efficiently amplified by loop-mediated isothermal amplification (LAMP) at 65 °C for 45 min. Pyrogallol-rich poly(tannic acid)-stabilized gold nanoparticles (PTA-AuNPs) served as colorimetric probes for direct visual detection of the DNA amplified using LAMP. The magnetic-nanogold (PEI-Fe₃O₄/PTA-AuNPs) hybrid system achieved a limit of quantification of 1 fg/µL. To facilitate field deployment, smartphone-based RGB analysis enabled quantitative and equipment-free readouts. Overall, the PEI-Fe₃O₄/PTA-AuNPs hybrid system used in NAT offers a rapid, cost-effective, and portable solution for DNA detection, making the system suitable for microbial monitoring. Full article

To investigate how sweating–drying processing affects the components, antioxidant activity, and hepatoprotective mechanisms of Eucommia ulmoides (EUB) against acute liver injury (ALI), this study constructed a “processing–active components–ALI targets” network. Eight processed EUB samples were analyzed using HPLC fingerprinting, multi-assay antioxidant tests (DPPH/ABTS·+/pyrogallol), network pharmacology, and molecular docking. Sweating–drying significantly altered EUB’s chemical profile, with HPLC fingerprint similarities ranging from 0.715 to 1.000, the lowest being for FG4 (40 °C dried after sweating) and FD (freeze-dried after sweating). Key components (chlorogenic acid (CA), pinoresinol diglucoside (PDG), aucubin (AU), geniposidic acid (GPA)) varied: XS (sun-dried) had the highest CA/PDG, while FG4 showed increased AU/GPA. FY (shade-dried after sweating) exhibited the strongest free radical scavenging (DPPH/ABTS·+/pyrogallol IC₅₀ = 0.828, 0.134, 14.200 mg/mL), which correlated with CA/PDG/liriodendrin (PD) synergy. Network pharmacology identified 205 EUB-ALI intersection targets (core: TNF, PTGS2, GAPDH) and the AGE-RAGE pathway; molecular docking confirmed strong CA/PDG binding to GAPDH/PTGS2. This study clarifies how processing regulates EUB’s components and their links to antioxidant and hepatoprotective effects, providing scientific support for EUB’s clinical application against ALI. Full article

Background: Hydrogen sulfide (H₂S) is an endogenously produced gaseous neurotransmitter. H₂S donors exhibited neuroprotection in oxidative-stress-related disorders in preclinical studies, but odor and short half-lives have limited their clinical use. However, endogenous H₂S stimulators with antioxidant properties have advantages over H₂S donors regarding safety and patient compliance. Empagliflozin (EMPA), a sodium–glucose cotransporter-2 (SGLT2) inhibitor widely used in the treatment of diabetes mellitus (DM), exerted similar neuroprotective and antioxidant effects as H₂S and shares common mechanisms. This study aimed to investigate the role of H₂S in the antioxidant effects of EMPA in the brain. Methods: The effects of EMPA on H₂S production and reactive oxygen species (ROS) formation were assessed ex vivo in mouse brain under normal conditions and pyrogallol-induced oxidative stress. Moreover, rats were divided into the following four groups: nondiabetic, EMPA-treated nondiabetic, streptozotocin (STZ)-induced diabetic, and EMPA-treated, STZ-induced diabetic. Endogenous H₂S and ROS levels in the brain were measured using methylene blue and chemiluminescence assays, respectively. Results: Ex vivo EMPA treatment significantly increased endogenous H₂S formation in both healthy and pyrogallol-induced oxidative stress, as well as reduced ROS formation in mouse brain; these effects were significantly reversed by the H₂S synthesis inhibitor aminooxyacetic acid (AOAA). Oral EMPA administration significantly elevated brain H₂S levels in both nondiabetic and diabetic rats and reduced ROS formation. These effects were inhibited by AOAA. Conclusions: Our study revealed a novel mechanism by which EMPA can reduce oxidative stress in neurodegenerative disorders by triggering H₂S synthesis in the brain. Full article

Methylglyoxal (MGO) is a highly reactive a-dicarbonyl compound produced in foods and endogenously in humans and constitutes a predominant precursor of advanced glycation end products that contribute to the pathology of several diseases, including diabetes and neurodegenerative diseases. In this study, the efficiency of pyrogallol, gallic acid, ethyl, and propyl gallate in trapping MGO was investigated at pH 6.5 to 8.0. Pyrogallol was the most efficient MGO-trapping agent, followed by gallic acid, whereas the alkyl gallates were notably less efficient, particularly at slightly acidic and neutral pH. The increase of pH from slightly acidic to alkaline enhanced the MGO-trapping efficiency of all compounds, albeit to a different extent that correlated inversely to the pK_a of the most acidic -OH phenolic group, demonstrating the contribution of the deprotonated forms of the phenolic compounds in the enhanced reactivity towards MGO. The reaction products of pyrogallol, identified as the most efficient compound in MGO-trapping, were analyzed and characterized by liquid chromatography-mass spectrometry (LC-MS). Both mono-MGO and di-MGO conjugated adducts of pyrogallol were detected, with the mono-MGO adduct being dominant solely at acidic pH and the di-MGO pyrogallol adducts becoming prevalent at neutral and alkaline pH. Therefore, the pH was determined as a main factor that controls the reaction pathways of the phenolic compounds with MGO. Full article

This study reports an improved diastereoselective synthesis of substituted spiro[chromane-2,4′-pyrimidin]-2′(3′H)-ones via the acid-catalyzed condensation of 6-styryl-4-aryldihydropyrimidin-2-ones with resorcinol, 2-methylresorcinol, and pyrogallol. The optimized method allows for the isolation of diastereomerically pure products, with stereoselectivity controlled by varying acid catalysts (e.g., methanesulfonic acid vs. toluenesulfonic acid) and solvent conditions. The synthesized compounds were evaluated for antimicrobial and antioxidant activities. Notably, the (2S*,4R*,6′R*)-diastereomers exhibited significant antibacterial activity against both Gram-positive and Gram-negative bacterial strains with minimal inhibition concentration down to 2 µg/mL, while derivatives containing vicinal bisphenol moieties demonstrated potent antioxidant activity, with IC₅₀ values (12.5 µg/mL) comparable to ascorbic acid. Pharmacokinetic analysis of selected hit compounds revealed favorable drug-like properties, including high gastrointestinal absorption and blood-brain barrier permeability. These findings highlight the potential of spirochromane-pyrimidine hybrids as promising candidates for further development in the treatment of infectious diseases and oxidative stress-related pathologies. Full article

The aim of this study was to determine the intraspecific variability among 11 wild-growing populations of wormwood (Artemisia absinthium L.) originating from Central Europe and preserved in the Polish Genebank Collection. The populations were introduced into ex situ conditions, and assessed in terms of selected developmental and chemical traits (essential oil, phenolic acids, polyphenols, and tannins content). Developmental observations and harvest of raw materials were carried out in the second year of plant vegetation, at the beginning of flowering. The populations exhibited significant differences. The greatest variability was observed in the number of shoots per plant (38–51) and dry mass of herb per plant (0.83–1.60 kg). Essential oil (EO) content ranged from 0.75 to 1.69 g/100 g dry weight (DW). A total of 41 compounds were identified in the EOs, with oxygenated monoterpenes (such as sabinyl acetate, cis-chrysanthenol, chrysantenyl acetate, 1,8-cineole, α- and β-thujone) as dominants, showing considerable variation among populations. Based on the EO profiles, several chemotypes were distinguished, mainly (1) a pure sabinyl acetate chemotype; (2) mixed chemotypes with sabinyl acetate accompanied by β-myrcene, cis-chrysanthenol, chrysanthenyl acetate, or 1,8-cineole; and (3) a thujone chemotype. The total content of phenolic acids (expressed as caffeic acid equivalent), tannins, and polyphenols (as pyrogallol equivalent) varied significantly, too (0.37–0.50; 0.10–0.26; 0.58–0.79%, respectively). The results confirm a high level of intraspecific variability in both developmental and chemical traits of A. absinthium populations originating from Poland. This diversity may be valuable for future breeding programs and for the selection of populations with desired phytochemical profiles for medicinal, food, and agricultural applications. It is worth noting that the floristic diversity among populations indicates the habitat heterogeneity, ranging from natural or semi-natural (populations 1, 6) to more anthropogenically influenced ones (populations 2, 4, 5, 7–11). Full article

A substrate–product switch model was proposed to describe ethanol fermentation from longan solid waste using Candida tropicalis at an initial glucose and xylose ratio of 2 to 1. The model incorporated multiple rate equations for cell growth, sugar uptake, and ethanol production along with ethanol consumption. It elucidated the following three-step mechanism: (I) sugar uptake, (II) sugar conversion, and (III) ethanol consumption concerning the effects of concentration factor (CF) and associated growth function. Optimal kinetic parameters were estimated and validated against experimental data. The identification of two critical xylose concentrations showed that ethanol consumption either preceded or coincided with xylose consumption cessation. The phenolics inhibitory effect of gallic acid, ellagic acid, pyrogallol, and catechol on cell growth and ethanol production was elucidated with relatively minimal effect. The highest ethanol concentration of 25.5 g/L was reached with corresponding ethanol mass yield and productivity of 0.30 g/g and 1.063 g/L/h, respectively. The proposed model and kinetics provide valuable insights for designing and optimizing ethanol fermentation, contributing to more sustainable and cost-effective ethanol production. Full article

The issue of interfacial inhomogeneity in energetic materials remains a significant challenge. In this study, fluoroelastomer F2602 was applied to HMX crystals using a water suspension granulation technique, followed by a bio-inspired coating formed via the crosslinking polymerization of polyethyleneimine (PEI) and pyrogallol (PG) on the HMX/F2602 composite. This process resulted in the formation of an HMX/F2602/PEI-PG microcapsule structure. Various characterization techniques confirmed that the chemical structure and polycrystalline morphology of the crystals were preserved throughout the coating process, maintaining the characteristic β-HMX morphology. The introduction of the PG–PEI shell significantly improved the coating coverage and minimized the exposure of crystal surfaces. Furthermore, compared to HMX/F2602, the HMX/F2602/PEI-PG composite exhibited notably enhanced thermal stability and reduced mechanical sensitivity. These improvements are attributed to the advantageous effects of the microcapsule structure formed by the bio-inspired coating on the material’s properties. Full article

Arthrospira platensis, a filamentous photosynthetic cyanobacterium, is widely recognized for its high nutritional value, broad spectrum of bioactive compounds, and excellent safety profile, making it a promising natural source for health-promoting applications. This study aimed to profile the phenolic constituents of an ethanolic extract of A. platensis (EAP) using HPLC-DAD-ESI-MS and to investigate its pharmacological effects in attenuating acute and sub-chronic experimental colitis, as well as its antioxidant and antifungal properties. Colitis was induced in BALB/c mice by intrarectal administration of 2,4-dinitrobenzenesulfonic acid (DNBS), followed by oral administration of EAP at doses of 50, 100, and 200 mg/kg. Phenolic profiling revealed eight major compounds, with a cumulative content of 6.777 mg/g of extract, with Pyrogallol, Ferulic acid, and Chlorogenic acid being the most abundant. In vivo, EAP treatment significantly reduced the Disease Activity Index (DAI), alleviated macroscopic colonic damage, and preserved colonic mucosal integrity in both inflammatory phases. Biochemical analyses revealed significant reductions in myeloperoxidase (MPO) activity, nitric oxide (NO), and malondialdehyde (MDA) levels, accompanied by increased reduced glutathione (GSH) content and catalase activity. In vitro, EAP demonstrated notable antioxidant effects, including 56% DPPH and 47% ABTS radical scavenging activities, and an 81% ferrous ion-chelating capacity. Furthermore, it exhibited antifungal activity, with inhibition zones of 20 mm against Candida albicans and 15 mm against Aspergillus flavus, respectively. These findings highlight the multitarget bioactivity of EAP and support its potential as a natural agent for managing intestinal inflammation and oxidative stress across both acute and sub-chronic phases. Full article

This review highlights how advances in silico techniques have shed new light on phenomena in confined supramolecular resorcinarene-based systems. Computational studies have provided detailed insights into capsule formation, their dynamic behavior, guest encapsulation and reaction mechanisms within these hosts, often revealing information that experimental methods cannot reach. The focus is placed on the self-assembly of resorcin[4]arenes, pyrogallol[4]arenes, velcrands, and octa acid systems. These computational studies complement experimental findings and, in many cases, offer new perspectives that are inaccessible using experimental techniques alone. Supramolecular architectures are growing in complexity the role of in silico approaches is becoming indispensable. They offer a way to design rationally and understand host–guest chemistry more deeply. Full article

This study explores the use of a deep eutectic solvent (DES) composed of choline chloride and pyrogallol (1:1 molar ratio) for the recovery of lithium, cobalt, and nickel from spent lithium-ion battery cathodes based on LiNi_0.33Co_0.33Mn_0.33O₂ (NMC111). The DES exhibits moderate viscosity, intrinsic redox activity, and strong complexation ability, enabling efficient metal dissolution under mild conditions. The effects of both temperature (50–80 °C) and time (up to 12 h) on leaching efficiency were systematically investigated. Optimal leaching parameters—80 °C, 8 h, and a liquid-to-solid ratio of 50—yielded extraction efficiencies of 92% for Li, 85% for Co, and 88% for Ni. Kinetic modeling indicated pseudo-first-order behavior with activation energies of 26.6, 22.1, and 25.2 kJ/mol for Li, Co, and Ni, respectively. Mechanistic analysis confirmed the dual role of pyrogallol as both reducing agent (facilitating Co³⁺ to Co²⁺ conversion) and chelating ligand. Full article

This study evaluated the antioxidant capacity of the oxidation products of three flavonols using oxygen radical absorbance capacity—fluorescein assay (ORAC-FL), oxygen radical absorbance capacity—pyrogallol red assay (ORAC-PGR), and the cellular antioxidant activity (CAA) assay in human dermal fibroblast (HFF) cells, with 2,2’-azobis(2-amidinopropane) dihydrochloride (AAPH) as a free radical generator under controlled pH and solvent conditions. At pH 2 in a polar aprotic solvent, BZF-OH (benzofuranone-OH) compounds were formed, while methoxylated analogs were obtained at pH 7 in a polar protic solvent. The products generated at pH 2 exhibited significantly higher antioxidant capacities, demonstrating the influence of the reaction environment on modulating antioxidant properties. The antioxidant activity was observed to reflect the combined action of the flavonol precursor and its oxidation products. This led to the proposal of the Gross Antioxidant Capacity (GAC) concept to integrate the contribution of all generated species. Since chemical assays such as ORAC do not fully capture the complexity of biological systems, they should be complemented with cellular approaches for a more accurate evaluation. Additionally, BZF-OH compounds were analyzed as potential cyclooxygenase-2 (COX-2) inhibitors through docking and molecular dynamics simulations, where BZF-Quer-OH showed binding affinities comparable to celecoxib, a selective COX-2 inhibitor. These findings were complemented by an analysis of COX-2 expression in RAW 264.7 cells treated with lipopolysaccharide (LPS), where treatment with the antioxidants significantly inhibited COX-2 expression. In the case of the oxidation products, only the oxidation product of rhamnetin showed a reduction in COX-2 expression compared to the LPS-treated control. Together, these results highlight that flavonol-derived oxidation products not only retain significant antioxidant capacity but may also possess anti-inflammatory properties, opening new perspectives for the development of innovative therapies targeting oxidative stress and chronic inflammation. Full article

Background/Objectives: Secondary metabolites encompass diverse groups of compounds; one such group is phenolics, which include small phenols up to larger polyphenols such as lignin and tannins. Smaller compounds such as phenolic acids can serve as substrates for soil microbes and enzymes. The specific interaction between plant secondary metabolites (PSMs) and soil enzymes determines whether the products of these reactions contribute to the formation of soil organic matter (SOM) or are degraded into small organic molecules. Methods: Here, we monitored the activity of a redox active soil enzyme, manganese peroxidase (MnP), with three small phenolic compounds. The compounds used in this study were pyrogallol, gallic acid, and benzoic acid. Results: Based on the kinetic parameters determined, pyrogallol and gallic acid are both substrates for MnP with different products and kinetics. Conclusion: Pyrogallol reacts faster and produces a more stable quinone than gallic acid. Benzoic acid is not a substrate for MnP. Full article

Shea butter (SB) is a raw material fat obtained from Vitellaria paradoxa C.F. Gaertn kernels. We investigated the direct and indirect protective effects of 10 traditional and industrial SBs and their polar extracts on cell-free systems using ABTS and DPPH radical scavenging assays as well as on singlet oxygen (¹O₂) produced by Rose Bengal (RB) photosensitization. Their effects against RB-induced HaCaT cell phototoxicity were also explored. A spectrophotometric assay and HPLC were performed to quantify and identify phenolic content, which was between 14.16 and 82.99 ppm pyrogallol equivalent. These variations could be due to the SB origin and extraction process. These polar fractions exhibited moderate DPPH and strong ABTS radical-scavenging activity. By applying the UV–visible technique, we demonstrated that SBs and their phenolic compounds behave as ¹O₂ quenchers in a dose-dependent manner. Moreover, using a UVR-like model after the irradiation of RB, both polar extracts and crude SB exhibited photoprotective effects, highlighting the indirect protective action. In acellular and cellular models, SB and its polar extracts can act as a free radical scavenger against reactive oxygen species and ¹O₂ quenchers. Due to the maximum absorbance of SB at 280 nm and the antioxidant effect of ¹O₂ quenching, SB polar extracts exhibit photoprotective properties. Full article