The chemistry of vitamin C adducts was revisited to investigate their pH sensitivity, photophysical properties, optical behavior, and assess their potential as eco-friendly pH indicators. In this study, a series of ascorbic acid adducts were synthesized through a straightforward, high-yield method. Their acid-base responsiveness is driven by a reversible protonation-deprotonation process between the hydrazineyl and azo groups, causing observable color changes. Analysis of substituent effects demonstrated that strong electron-withdrawing groups like nitro (-NO2) significantly impact the electronic structure, particularly when located at the ortho or para positions of the aromatic ring. Solvatochromic studies revealed that the ortho-nitro adduct 3(b) and para-nitro adduct 3(d) exhibited positive solvatochromism, with their absorption wavelengths increasing in more polar solvents. Notably, 3(b) displayed a consistent yellow color with λmax around 396 nm across solvents, indicating its structural stability and solvent-independent optical behavior, making it a robust and versatile pH indicator. Halochromic studies in aqueous media revealed pronounced bathochromic shifts for both 3(b) and 3(d) under alkaline conditions. The 3(b) exhibited a color change from yellow to dark purple (λmax = 534 nm), while the 3(d) transitioned from colorless (λmax = 361 nm) to dark rosewood (λmax = 472 nm). Spectrographic analysis determined that 3(b) had a pKa of 8.99 and 3(d) a pKa of 10.68. The band gap analyses conducted under both alkaline and acidic conditions provide detailed insights into the optical properties and electronic transitions of the most promising adducts, 3(b) and 3(d). The optical band gap energies obtained from UV-Vis spectroscopy, Eg(optical) and Eg(Tauc), showed strong agreement with the electrochemically measured band gap, Eg(electronic). These findings were further corroborated by computational results from DFT (B3LYP/6-311 + G(d,p)), where the theoretically calculated band gaps, Eg(DFT), validated the experimentally derived values and provided additional information through frontier molecular orbital (FMO) analysis, indicating the presence of an efficient push-pull electronic system throughout the adduct structures. Correlation of DFT outputs with Tauc-plot analyses clarified the nature of the electronic transitions, including π → π*, n → π*, and intramolecular charge-transfer (ICT) processes, and determined whether these transitions were direct or indirect, and whether they were symmetry-allowed or forbidden. Biochemical assays further supported the proposed neutral proton-transfer mechanisms operating under both acidic and basic conditions for the promising adducts. Thermal analysis divulged thermal stability up to 210 °C. Acid-based titration tests showed that 3(b) and 3(d) produced sharp and accurate endpoints comparable to the standard methyl red indicator, while 3(c) did not exhibit a reliable color transition. Given their green origin, tunable structures, and visual responsiveness, these ascorbic pH indicators hold promising candidates for sustainable applications in food coloration, cosmetics, and medical diagnostics.

Phenolic endocrine disrupting compounds (EDCs) contamination poses a serious public health and environmental threat, therefore develop sensitive and selective detection method for phenolic EDCs is highly desirable. A porous organic polymer (DT-POP3) was synthesized by azo coupling of 2,4,6-tris(o-hydroxyaryl)-1,3,5-triazines and 4,4''-diamino-p-terphenyl. DT-POP3 exhibited high adsorption capacity and fast adsorption kinetics for phenolic EDCs through the hydrogen bond force and π-π stacking interaction. With DT-POP3 as solid-phase extraction adsorbent, a LC-MS method was established to detect phenolic EDCs in fish. The method exhibited wide linear range (4.00-1000 ng·g-1), low detection limit (S/N = 3) (1.20-6.50 ng·g-1), high spiked recoveries (82.9-118.8%) and low relative standard deviation (1.8-9.6%). The contribution of this study is not merely the proposal of a viable adsorption/detection method for trace phenolic EDCs, but also concurrently establishes a novel paradigm for the development of functional materials aimed at removing organic pollutants.

Non-communicable diseases (NCDs) have exceeded infectious diseases as a global health threat. This shift has occurred concurrently with changes to lifestyle and diet, of which the increased consumption of ultra-processed foods (UPFs) is particularly concerning. UPFs are defined by industrial processing of often cheaply sourced natural food and inclusion of non-nutritional additives such as azo-dye colourants, non-caloric sweeteners, emulsifiers and preservatives. They now account for approximately half of the caloric intake in many countries and notably by children. These products can compromise nutritional quality while promoting hedonistic hunger and disrupting the gut microbiota. Population studies are increasingly demonstrating an association between high UPF consumption and increased all-cause mortality, obesity, cardiovascular disease, cancer risk, mental health and neuro-behavioural disorders. While association studies cannot account for all potential confounding factors, triangulation through combining large-scale cohort studies with animal/in vitro models and human challenge studies provides more compelling evidence that UPFs increase the risks of NCDs. Despite the increasing evidence, regulatory action on their use has remained limited. We review the evidence and explore the reasons why effective regulation is lacking, with increasing examples of inappropriate food industry influence on political decisions in several countries. The current focus on reducing consumption of high fat, sugar and salt has distracted attention from the adverse effects of alternative non-nutritional additives. We propose changes to food labelling and call for public health interventions to combat and minimise UPF consumption. These interventions are especially vital for socioeconomically disadvantaged populations and children, who increasingly consume UPFs as attractive and cheaper alternatives to fresh or minimally processed products. Urgent action is needed to promote healthier dietary practices worldwide.

A series of new azo-imidazolones-based azo dye were synthesized, and spectral characterization accomplished by using different spectrophotometric and spectrometric techniques such as FT-IR, UV-visible, 13C NMR, 1H NMR, DEPT-135, ESI-MS, and fluorescence spectroscopy. Biological evaluation included testing antibacterial properties under standard media, smart antibacterial screening tested by exposing the sample to UV light and determining the minimum inhibitory concentration (MIC), testing antifungal properties using a well diffusion assay, comparing antioxidant activity with ascorbic acid, and molecular docking studies targeting bacteria, fungi, and cancer cells. The cytotoxicity MTT assay on MCF-7 cells of synthesis compound C3 was also evaluated. The selectivity index (SI) was determined by comparing standard cell lines (WI-38/HFF. The P values of the hydrophobic nature of the synthesized compounds were calculated, and the compounds exhibited a hydrophobic nature with the potential to be permeated through the membrane Pfizer's criteria of intravenous injection were therefore used. All studies have been performed using appropriate controls and according to approved protocols.

Glucose-6-phosphate dehydrogenase (G6PD) deficiency is a genetic X-linked recessive disorder that results from mutations in the G6PD gene, which provides instructions for manufacturing the G6PD enzyme. G6PD deficiency primarily impacts red blood cells. This deficiency can result in hemolytic anemia (HA), in which rapid destruction of red blood cells occurs due to the vulnerability of erythrocytes to reactive oxygen species. It is most commonly found in males and affects 1 in 10 Black males in the United States. Persons with G6PD deficiency may exhibit symptoms such as pallor, jaundice, dark urine, fatigue, tachycardia, shortness of breath, and splenomegaly. Exposure to certain medications such as rasburicase, sulfonamides, nitrofurantoin, antimalarials, dapsone, chloramphenicol, high-dose aspirin, methylene blue, and phenazopyridine may trigger a hemolytic crisis in those with G6PD deficiency. Tests used in the diagnosis of HA include the Coombs test, haptoglobin, complete blood count, urinalysis, lactate dehydrogenase, bone marrow tests, and a peripheral blood smear. This article summarizes the case of a patient who developed HA after an infusion of rasburicase and offers management strategies.

Apoptosis plays a critical role in maintaining tissue homeostasis and preventing pathological conditions. The accurate detection of apoptosis is crucial for both research and diagnostic pathology, yet conventional histological staining methods often lack the sensitivity to identify early apoptotic changes. This study aimed to evaluate and compare the effectiveness of classical and emerging mitochondria-targeting histological techniques in detecting apoptotic hepatocytes. Paraffinated hepatic tissue from five rabbits was analysed using haematoxylin-eosin (H&E), Goldner's trichrome (GT), immunohistochemistry for caspase-3 (IHC-Casp3) and Heidenhain's iron haematoxylin (HIH) staining. The percentage of apoptotic hepatocytes was quantified using two assessment methods, and statistical analyses determined the sensitivity of staining protocols. Histologically, the main apoptotic features identified in HIH-stained hepatic specimens were fading 'ghost' mitochondria throughout the cytoplasm, chromatin condensation, fragmentation and dissolution and nucleolar margination. A similar proportion of apoptotic hepatocytes on the HIH staining compared to IHC-Casp3 (19.00% ± 0.7 for HIH vs. 18.50% ± 0.7 for IHC-Casp3) was observed. In comparison, significantly lower values were obtained in H&E (5.75%) and GT (7.5%) stains. The lack of statistical significance of HIH vs. IHC-Casp3 demonstrates similar sensitivities. The additional quantitative analysis methods confirmed IHC as the most sensitive method (3.36 ± 3.82 apoptotic cells/field), followed by HIH, H&E, and GT. In situ histological evaluation of apoptosis remains challenging in standard H&E and GT-stained sections. HIH stain, as a cost-effective alternative to IHC, highlights early stages of apoptotic cells, providing a significant advantage over classical staining methods, emphasising their importance in diagnostic histopathology.

A potential-resolved chronoamperometric strategy based on an H-CoFe2O4NPs@CFP electrode was developed for simultaneous detection of indigo carmine (IC), ponceau 4R (Pon), and amaranth (Amar) in a ternary mixture. Sequential measurements at 0.35, 0.56, and 0.69 V in 0.1 M phosphate buffer (pH 7.0) enabled effective signal deconvolution. For the mixed system with a fixed 1:1:1 M ratio, linear ranges normalized to individual dye concentrations were 0.1-160 μM (IC), 0.5-140 μM (Pon), and 0.1-140 μM (Amar), with detection limits of 0.044, 0.144, and 0.040 μM, respectively (S/N = 3, R[2] ≥ 0.994). Spiked recoveries of 94.7-105.3% with relative standard deviations ≤4.81% in candy coatings, fruit juices, and iced tea demonstrated good accuracy and precision. This method shows promise for food safety monitoring.

Xylenol orange (XO) is a persistent anionic azo dye that resists conventional treatment. Cetyltrimethylammonium bromide (CTAB) and binding poly (vinylpyrrolidone) (PVP) were sequentially intercalated onto Na-montmorillonite (NaMt) to prepare a CTAB/PVP-modified Na-montmorillonite (CP-NaMt), and its adsorption toward XO was evaluated. The nanostructured adsorbent was characterized by chemical analysis, morphological, phase analysis, and point-of-zero-charge measurements. The characterization indicated successful organic intercalation accompanied by slight basal-spacing expansion, partial layer exfoliation and the development of a hierarchical micro-mesoporous structure. The Brunauer-Emmett-Teller specific surface area increased from 46.5 to 88.7 m[2]·g[-1]. Batch tests identified pH = 5 as optimal, consistent with XO speciation and the positively charged surface of CP-NaMt. The adsorption process reached equilibrium rapidly, with a maximum capacity of 93.85 mg·g[-1] achieved within 40 min at 30 °C. Kinetics followed a pseudo-second-order model and intraparticle-diffusion analysis indicated multistage transport beginning with a film-diffusion regime. Equilibrium isotherms were better described by the Langmuir model. Thermodynamic analysis indicated a spontaneous, endothermic process with an entropy gain that facilitates desolvation and mass transport. Regeneration with ethanol maintained ≥ 87.4% removal over five cycles. Spectroscopic evidence and control experiments supported a mechanism dominated by electrostatic ion pairing at quaternary ammonium sites, further stabilized by hydrogen bonding and hydrophobic partitioning and π-π stacking within organic microdomains. This low-cost, regenerable clay platform shows potential for polishing dye-laden wastewater.

The growing interest in multifunctional antioxidants has drawn attention to hybrid scaffolds that unify distinct redox-active pharmacophores. Azo groups, aroylhydrazones, and gallic acid derivatives are individually recognized for their notable antioxidant potential, yet molecular hybrids integrating all three remain scarce. To address this gap, a new series of compounds (5a-j) combining azo, aroylhydrazone, and polyhydroxyphenyl moieties was designed and synthesized to enhance antioxidant activity through structural synergy. The synthesized molecules were thoroughly characterized by FTIR, [1]H, [13]C NMR, 2D NOESY/COSY, UV-Vis, and mass spectrometry. Their electronic and structural properties were further evaluated using DFT calculations at the B3LYP/6-311++G(d,p) level. In silico ADMEt predictions and molecular docking studies revealed favorable pharmacokinetic profiles and strong binding affinities toward key antioxidant-related enzymes-glutathione reductase (PDB: 1XAN), myeloperoxidase (PDB: 3F9P), and NAD(P)H oxidase (PDB: 2CDU). In vitro antioxidant activity was assessed using CUPRAC and DPPH assays, with Trolox serving as the standard. Remarkably, this is the first study to report the combined use of DMF in the CUPRAC and DMSO in the DPPH assays, offering a novel solvent strategy that enhanced compound solubility and assay compatibility. Among the tested compounds, 5b and 5e showed the highest antioxidant activities, surpassing Trolox in both methods. These results suggest that the azo-aroylhydrazone-polyphenol hybrid structure holds strong promise as a platform for developing next-generation antioxidant agents.

Background and objective Melanin production is a distinguishing taxonomic and functional trait of Streptomyces species. The pigment exhibits antioxidant properties, making it relevant for use in medicine, cosmetics, and the food industry. Its potential in supporting health and mitigating oxidative stress highlights its value in various biotechnological applications. This study aimed to isolate melanin-producing Streptomyces strains from rhizosphere soil, characterize the pigment through biochemical tests, optimize production conditions, and explore its antioxidant, antimicrobial (against Gram-positive and Gram-negative pathogens), and bioremediation capabilities, as well as its role in nanoparticle synthesis. Methods Cultivation of the isolates was carried out using peptone-yeast extract, and tyrosine-casein agar media were employed for pigment screening. The pigment was tested for reactivity with L-tyrosine and L-dihydroxyphenylalanine (L-DOPA). Various carbon and nitrogen substrates were tested to assess their influence on pigment production. Antioxidant activity was assessed using the 1,1-diphenyl-2-picrylhydrazyl (DPPH) assay, chosen for its simplicity, rapidity, and widespread use in evaluating radical-scavenging properties of natural pigments. Antimicrobial potential was tested against selected pathogens (including Gram-positive and Gram-negative bacteria). The biodegradation ability was examined through the decolorization of azo dyes. Biosurfactant activity and tolerance to heavy metals were also assessed. Additionally, crude pigment was utilized to facilitate the formation of copper nanoparticles, exploring potential applications in cancer-related studies. Each assay was conducted three times independently, and the obtained results are presented as mean ± standard deviation (SD) for statistical validity. Results The isolates were found to produce a diffusible pigment with coloration from dark brown to black that was soluble in water. It reacted positively with both L-tyrosine and L-DOPA. Optimization of media components led to increased pigment production. The final pigment was purified and exhibited significant antioxidant potential and was able to prevent the proliferation of bacterial and fungal test strains. Azo dyes were decolorized to a high level of 97.95, which means that the dyes are highly biodegraded. The strains were also biosurfactant active and had resistance to a range of heavy metals. The pigment was successfully synthesized into copper nanoparticles, and the biosynthesis of nanoparticles was verified using UV-Vis spectroscopy of the sample (absorbance peaks that are indicative of the nanoparticle formation), which further justifies the use of this pigment in therapeutic applications. Conclusions The strains of Streptomyces used in this study have shown several valuable characteristics of their pigment, which include antioxidant, antimicrobial, and pollutant-degrading capabilities. Based on this observation, the environmental, medical, and technological applications have various benefits that may be tapped.

Glucose-6-phosphate dehydrogenase (G6PD) is an enzyme found in the cytoplasm of all cells in the body. It is a housekeeping enzyme that plays a vital role in the prevention of cellular damage from reactive oxygen species (ROS). It does this by providing substrates to prevent oxidative damage. Erythrocytes are particularly vulnerable to ROS due to their role in oxygen transport and inability to replace cellular proteins as mature cells. Inherited deficiencies of G6PD can result in acute hemolytic anemia during times of increased ROS production. This may be caused by stress or exposure to certain foods that contain high amounts of oxidative substances, for example, fava beans, or certain medications.  In particular, anti-malarial agents have a strong association with inducing hemolytic anemia in patients with G6PD deficiency. Below are medications more commonly used in the United States that have been shown to trigger a hemolytic crisis in those with G6PD deficiency; however, a more comprehensive list of medications to be avoided has been published by the Italian G6PD Deficiency Association and can be found at www.g6pd.org.[1][2][3][4] Common medications to be avoided or used with caution in G6PD-deficient patients include: Acetaminophen. Acetylsalicylic acid. Chloramphenicol. Chloroquine. Colchicine. Diaminodiphenyl sulfone. Diphenhydramine. Glyburide. Isoniazid. L-Dopa. Methylene blue. Nitrofurantoin. Phenazopyridine. Primaquine. Rasburicase. Streptomycin. Sulfacetamide. Sulfanilamide. Sulfapyridine. Sulfacytine. Sulfadiazine. Sulfaguanidine. Sulfamethoxazole. Sulfisoxazole. Trimethoprim. Tripelennamine. Vitamin K.

Methemoglobinemia is a rare but serious condition affecting the blood's ability to carry oxygen. Symptoms at presentation are often nonspecific. We describe the case of a 58-year-old female presenting with unexplained central cyanosis and severe hypoxia despite preserved respiratory effort and seemingly reassuring lab values. Further questioning revealed recent ingestion of a large quantity of phenazopyridine, an over-the-counter urinary analgesic known to cause oxidative stress. Co-oximetry confirmed significant elevation of methemoglobin levels. Methylene blue is well-regarded as the gold standard, and its use in treatment of this patient led to favorable clinical and laboratory improvement. Clinicians must maintain a high index of suspicion for dyshemoglobinemias in patients with unexplained cyanosis refractory to oxygen therapy, particularly when conventional metrics of oxygenation are inconsistent with the overall clinical picture.