Search Results (219)

Opuntia ficus-indica (L.) Mill., an edible cactus, has gained increasing attention as a potential food resource due to its adaptability and nutritional value. This study aimed to characterize the bioactive compound profiles and structural characteristics of the epidermis and cortex of cladodes across different maturity stages. Numerically higher levels of bioactive compounds were generally observed in the epidermis than in the cortex, particularly gentisic acid (384.58–668.23 µg/g DW in the epidermis vs. 191.11–426.69 µg/g DW in the cortex) and protocatechuic acid (154.04–234.45 µg/g DW in the epidermis vs. 40.78–118.44 µg/g DW in the cortex). The epidermis and cortex also exhibited distinct organic acid profiles, with oxalic and malic acids being the predominant organic acids detected in both tissues. FTIR analysis further revealed a more pronounced O–H absorption band associated with water molecules in the cortex than in the epidermis. Furthermore, stage-dependent variations were observed in both bioactive composition and structural characteristics. Organic acids exhibited stage-dependent variations in both tissues. Oxalic, malic, and succinic acids generally occurred at higher levels during the later maturity stages, whereas fumaric acid was more abundant at the earliest maturity stages. Their concentrations ranged from 13.61–47.20, 10.74–16.27, 7.56–14.47, and 0.51–20.46 mg/g DW in the epidermis, and 8.19–46.82, 9.67–52.26, 2.76–14.72, and 0.27–34.41 mg/g DW in the cortex, respectively. These findings provide baseline information on the compositional and structural characteristics of edible cactus cladodes and may support future studies on their potential food-related applications. Full article

Objective: Disorders of gut–brain interaction (DGBIs) are characterized by functional impairments without identifiable organic causes, with their prevalence increasing with age. Emerging evidence suggests that selective serotonin reuptake inhibitors (SSRIs), such as escitalopram oxalate, may influence DGBIs through the brain–gut axis, though the precise mechanisms driving their therapeutic effects remain unclear. This study investigated the impact of escitalopram oxalate on elderly patients with DGBIs in an outpatient department to elucidate these mechanisms. Methods: This study was an observational cohort study. We recruited elderly patients diagnosed with DGBIs. Patients receiving standard treatment alone were assigned to the control group, while patients receiving standard treatment plus 10 mg of escitalopram oxalate daily were assigned to the exposure group. Emotional and gastrointestinal symptoms were assessed at baseline and after 12 weeks of treatment using validated symptom scales. Additionally, stool samples were collected at both time points and analyzed via 16S amplicon sequencing to evaluate the changes in gut microbiota. Results: A total of 83 elderly patients with DGBIs were included in the study, comprising 40 patients in the control group and 43 in the exposure group. After 12 weeks, the exposure group showed significantly greater reductions in their scores on the Gastrointestinal Symptom Rating Scale (GSRS), Short-Form Leeds Dyspepsia Questionnaire (SF-LDQ), Zung Self-Rating Depression Scale (SDS) and Zung Self-Rating Anxiety Scale (SAS) compared with the control group (e.g., GSRS: 17.00 ± 0.85 vs. 22.58 ± 3.18, p < 0.001; p < 0.01 for all other scale comparisons), with higher effective and recovery rates. Notably, the exposure group showed significant alterations in the abundance of four genus-level taxa (Blautia, Butyricicoccus, Prevotellaceae UCG-003, and Streptococcus) and two species-level taxa (Eubacterium-hallii-group and Parabacteroides-merdae). Conclusions: The escitalopram oxalate treatment was associated with significant improvements in both emotional and gastrointestinal symptoms in elderly patients with DGBIs. These improvements may be linked to alterations in specific gut microbiota taxa, offering a preliminary hypothesis for further investigating the underlying mechanisms of the gut–brain axis. Full article

This in vitro study examined the influence of supersaturation level on the efficacy of different inhibitors in preventing the crystallization of calcium oxalate, uric acid, and cystine. Kinetic–turbidimetric assays were used to determine the induction time of crystallization (t_i) in the absence and presence of different inhibitors. For calcium oxalate, the inhibitory effects of citrate, hydroxycitrate, tartronate, and phytate decreased significantly as the Ca²⁺ concentration increased from 220 mg/L to 240 mg/L. The polyhydroxycarboxylic compounds (citrate, hydroxycitrate, tartronate) can form complexes with calcium ions, decreasing overall supersaturation. Even though phytate also forms complexes with calcium, its urinary concentration is much lower than that of calcium, so the decrease in supersaturation can be considered negligible. For uric acid, theobromine and two of its metabolites (3-methylxanthine and 7-methylxanthine) inhibited the formation of these crystals. For each compound, the efficacy of inhibition decreased as the supersaturation of uric acid increased. For cystine, the inhibitory effect of N-acetylcysteine was lower at pH 4.5 and 5.0 than at pH 6.0. These studies of the crystallization of calcium oxalate, uric acid, and cystine showed that the efficacy of crystallization inhibitors decreased as the level of supersaturation increased. The results demonstrate that, in patients prone to kidney stone formation, the effectiveness of crystallization inhibitors can be improved by reducing the supersaturation of the specific stone-forming compound. Full article

Oxalic acid is extensively used in industrial chemical processes, purification systems, hydrometallurgical operations, and advanced oxidation environments where rapid and environmentally sustainable analytical methodologies are increasingly required for process monitoring and quality control. In this study, a micro-Raman spectroscopy methodology was developed for the direct quantification of oxalic acid in aqueous systems at moderate-to-high concentrations (0.079–0.793 M). The analytical strategy was based on the integrated Raman response of the carbonyl stretching region (1700–1750 cm⁻¹), selected due to its strong concentration-dependent behavior, spectral definition, and reduced interference from the aqueous matrix. The proposed methodology demonstrated excellent analytical performance, including high linearity (R² > 0.998), satisfactory precision, and reliable concentration-dependent reproducibility throughout the evaluated concentration range. To evaluate operational robustness, matrix-matched standards incorporating temperature variation (25–40 °C), turbidity (0–57 mg/L), dissolved Ca²⁺ (0–58 mg/L), and dissolved Fe³⁺ (0–7 mg/L) were prepared to simulate chemically perturbed industrial environments. Principal Component Analysis (PCA) demonstrated that the carbonyl vibrational region retained organized concentration-dependent spectral behavior despite operational perturbations. Partial Least Squares (PLS) regression models developed under these matrix-informed conditions preserved strong predictive capability (R² ≈ 0.997), while preliminary prediction of process-related samples yielded excellent agreement between predicted and reference concentrations (R² = 0.990). Although operational perturbations produced substantial attenuation of Raman intensity, particularly at lower concentration levels, the carbonyl Raman band remained spectrally detectable and analytically interpretable throughout all evaluated conditions. Electronic-structure analysis using Natural Bond Orbital (NBO) and Atoms-in-Molecules (AIM) methodologies demonstrated that the strong analytical behavior of the ν(C=O) vibrational mode is associated with enhanced electron-density localization, covalent stabilization, and favorable polarizability characteristics of the carbonyl bond. The combined experimental, chemometric, and computational results demonstrate the feasibility of matrix-informed micro-Raman spectroscopy as a rapid, reagent-free, and operationally robust methodology for oxalic acid monitoring in chemically perturbed aqueous industrial systems. Full article

Olive pomace is a major side stream originating from olive processing for the production of olive oil. This waste material bears a load of polyphenolic antioxidants, and thus it might serve as a source of precious phytochemicals. This work had as its objective the development of an extraction process for the efficacious recovery of polyphenols from dried olive pomace (dOP), employing eco-friendly extraction media. To this end, environmentally benign solvents were first compared for their efficiency in obtaining increased yields in total polyphenols, and 40% aqueous isopropanol was selected as the best-performing mixture. Further examination of the role of acidification showed that mineral acid addition (sulfuric, hydrochloric) had a rather negative effect on polyphenol yield. To the contrary, incorporation of oxalic acid into the solvent at a 10% level provided significantly higher extraction yield (p < 0.05), which reached 27.1 ± 1.1 mg caffeic acid equivalents (CAE) per g dOP. This solvent system (40% isopropanol/10% oxalic acid) was additionally scrutinized for its effectiveness by studying the role of process severity and response surface optimization. Out of both approaches, it was demonstrated that polyphenol extraction yield, but also antiradical activity, was directly correlated with residence time and temperature, within the limits tested. Moreover, a high correlation between polyphenol concentration and antiradical activity was also revealed. Liquid chromatography-tandem mass spectrometry analyses showed that the extract obtained with the solvent system used (40% isopropanol/10% oxalic acid) was characterized by the presence of both hydroxytyrosol and the flavone luteolin (242.1 and 178.6 μg g⁻¹ dOP, respectively), but, in the absence of isopropanol, the extract produced was largely dominated by hydroxytyrosol (4629.7 μg g⁻¹ dOP). Thus, it was concluded that the solvent system could fundamentally diversify extract composition. It is proposed that, when combined with integrated biorefinery technologies, this approach could effectively contribute to reducing environmental impacts while enabling the production of valuable natural antioxidants or platform chemicals that are vital for the food, pharmaceutical, and cosmetic industries. Within the broader context of sustainable food waste management, such strategies might be key elements of a circular economy framework. Full article

Atraphaxis virgata and Atraphaxis pyrifolia are xerophytic species of the Polygonaceae family that remain insufficiently characterized from pharmacognostic, phytochemical, and toxicological perspectives. This study provides an integrated evaluation of both species through anatomical authentication, sequential extraction of CO₂-extracted residual biomass, GC–MS and LC–MS metabolite profiling, and acute oral toxicity assessment. Anatomical analysis revealed shared xeromorphic traits, including cuticular protection, dorsiventral mesophyll organization, structured vascular bundles, and calcium oxalate druses. It also identified species-specific differences in leaf thickness, mesophyll arrangement, vascular architecture, and druse morphology. GC–MS analysis showed distinct chemical profiles: A. virgata displayed a concentrated profile dominated by acetophenone- and benzofuran-related constituents, whereas A. pyrifolia showed a broader spectrum of carbohydrate-derived, phenolic-related, and oxygenated constituents. LC–MS analysis supported the tentative annotation of diverse polyphenolic classes, including flavonoids, phenolic acids, coumarins, and phenylpropanoid derivatives. Acute oral toxicity testing showed no mortality at doses up to 2000 mg/kg, supporting a low acute oral toxicity classification under the tested conditions. However, histological examination revealed mild to moderate dose-dependent alterations in liver and kidney tissues at higher doses. The novelty of this work lies in linking diagnostic anatomical traits, species-specific metabolite patterns, residual biomass valorization, and preliminary safety evidence within a single comparative framework. These findings provide a basis for pharmacognostic authentication, phytochemical standardization, and future bioactivity-guided evaluation of Atraphaxis species. Full article

The mezcal industry in Mexico generates substantial volumes of vinasse, a waste product rich in organic material and bioactive compounds, yet its environmental impact and potential valorization in the food and biotechnological field remain underexplored. This study presents a comprehensive physicochemical and functional characterization of mezcal vinasse derived from mezcal production, including antioxidant activity and cytotoxicity assessment. Proximate analysis revealed high moisture content (96%) and a carbohydrate-rich profile (87.58% dry basis), with notable fiber fractions predominantly composed of insoluble dietary fiber (9.10% dry basis). Low-molecular-weight carbohydrate analysis identified fructose (60.46%) and glucose (10.48%) as the major components, and the hydrolyzed sample showed a monomeric profile with arabinose (31.98%) and glucose (24.14%) as the predominant sugars. Vinasse was found to provide antioxidant activity, as assessed by DPPH (296.3 µmol TE/g) and ABTS (465.3 µmol TE/g) colorimetric assays. Undesirable and antinutritional compounds such as tannins (15.3 mg catechin/g), oxalates (14.6 mg sodium oxalate/g), hydroxymethyl furfural (HMF) (3830.0 mg/L), and furfural (160.0 mg/L) were also quantified, highlighting potential environmental and nutritional concerns due to its mutagenic character at high concentrations. Despite these challenges, vinasse exhibited no cytotoxicity in Caco-2 cells at tested concentrations (25 to 100 mg/mL of phenolic extract), suggesting feasibility for further biotechnological applications. Full article

Urolithiasis is a condition characterized by the crystallization of urinary solutes and their accumulation as solid aggregates in the urinary tract. Effective pharmacological strategies for preventing crystal formation and oxidative stress-related urinary disorders remain limited. Mimosa malacophylla is traditionally used in northeastern Mexico for kidney disorders; however, its biological activities have not been fully characterized. In this study, a methanolic extract of M. malacophylla was obtained by maceration and evaluated for its phytochemical profile and biological activities. Preliminary phytochemical screening, total phenolic content, and high-performance liquid chromatography coupled to mass spectrometry (HPLC-MS) were used to characterize the extract. Antiurolithic activity was assessed by a calcium oxalate nucleation assay, while antioxidant, antimicrobial, hemolytic, and brine shrimp lethality assays were also performed. The extract showed a yield of 6.25% (w/w) and a total phenolic content of 6.41 mg GAE/g of extract. HPLC-MS analysis revealed a profile rich in flavonoid glycosides and phenolic derivatives, including rutin, luteolin, and apigenin. The extract exhibited under in vitro conditions a high inhibitory effect on calcium oxalate nucleation (95.47%) and notable antioxidant capacity, while no antibacterial activity was detected. Hemolysis was below 1% and the LD₅₀ in Artemia salina was 1174.23 ± 17.94 μg/mL. These findings suggest that M. malacophylla may be a source of bioactive compounds with potential relevance in early stages of crystal formation for the management of urolithiasis. Full article

Sclerotinia sclerotiorum (Lib.) de Bary is a globally distributed necrotrophic fungal pathogen capable of infecting a wide range of crops. While conventional chemical fungicides offer effective control, their long-term use leads to increased fungicide resistance and poses risks to the environment and human health due to pesticide residues, underscoring the urgent need to develop novel fungicides. Artemisinin, first identified in Artemisia annua, is renowned for its antimalarial activity. Here, we demonstrate that artemisinin exhibites effective antifungal activity against Sclerotinia sclerotiorum with an EC₅₀ value of 0.1 mg/mL. Treatment with artemisinin caused the mycelia surface to collapse and shrivel, accompanied by enhanced membrane permeability. Pretreating Brassica napus and Arabidopsis leaves with artemisinin increased resistance to S. sclerotiorum infection. Proteomic analysis revealed that artemisinin treatment markedly downregulated the expression of key functional proteins in S. sclerotiorum, including enzymes involved in oxalic acid biosynthesis, cell wall-associated proteins, and secreted proteins. In conclusion, artemisinin exhibits notable inhibitory effects against S. sclerotiorum and may hold potential for development as a novel fungicide. Full article

This study addresses the challenges associated with deep-well drilling mud cuttings, including large waste volumes, high transportation costs, and complex organic pollutants. A low-cost synergistic technology was developed for the resource utilization of pyrolyzed drilling waste residue (PDWR) and the in situ remediation of oil-contaminated drill cuttings. A ternary photocatalytic system consisting of PDWR, H₂O₂, and oxalic acid was proposed and demonstrated to effectively degrade total petroleum hydrocarbons (TPH) in drill cuttings under solar irradiation. Systematic optimization identified optimal dosages of PDWR, H₂O₂, and oxalic acid as 250 mg, 280 mg, and 90 mg, respectively. The addition of oxalic acid significantly enhanced photocatalytic oxidation performance, increasing H₂O₂ utilization by 63.8% and improving the TPH degradation rate by a factor of 3.03. Under optimal conditions and 7 days of solar irradiation, TPH degradation efficiencies of 65.19–88.66% were achieved for initial TPH concentrations ranging from 5000 to 12,000 mg kg⁻¹. Mechanistic analysis revealed that a Fenton-like reaction between transition metals in PDWR and H₂O₂ dominated the photocatalytic process, while oxalic acid facilitated metal redox cycling through coordination and electron transfer, promoting sustained generation of reactive oxygen species (·OH). This study demonstrates a feasible and sustainable approach for high-value utilization of drilling waste residue and solar-driven in situ remediation of oil-contaminated drill cuttings, highlighting its strong potential for practical application. Full article

Calcium oxalate (CaOx) crystals in plants can form naturally within their idioblasts but may also be induced by other factors, such as environmental pollution. Here, we report qualitative and semiquantitative results obtained using scanning electron microscopy (SEM) and energy-dispersive X-ray (EDX) from two experiments in which tomato seedlings were moderately irrigated with Sulfamethoxazole (SMX) and Amoxicillin (AMX) solutions (0.25 mM). Abundant prismatic CaOx co-crystals appeared on the leaf surface induced by these two antibiotics compared to the distilled water (DW) control. Applying a non-thermal plasma (NTP) treatment for 20 min (T20) to the SMX initial solution led to a dramatic suppression of these crystals, with a shift toward spherical structures. Furthermore, the investigation into the composition of both crystal types, indicated different percentual levels of O, C, Ca, K, Mg, S, and Mn as main constituent minerals involved in crystal formation. However, crystal morphology was affected by each applied experimental condition, while detecting their constituent elements depended on their mineral homogeneity at the micro- or macro-field scales. Although both antibiotics induced crystal formation and T20 phenotypically reduced the abundance of the acicular–prismatic crystals by removing the effects of SMX, their mode of action has not yet been clarified. Full article

The NdFeB magnetic material is widely used in modern industry and electronics. Recycling spent magnets containing 30–40 wt.% Rare Earth Elements (REEs) and 60–70 wt.% iron is essential for resource recovery. This study focuses on treating wastewater from hydrometallurgical REE extraction to enable water reuse and iron recovery. Experiments investigated the influence of temperature (25–60 °C) and oxalic acid concentration (50–120% stoichiometric amount) on iron precipitation as the main focus. Optimal iron recovery of 85.3% and 86.8% was achieved at 25 °C using 80% and 100% stoichiometric oxalic acid, respectively. Simultaneously, praseodymium removal exceeded 94%. The Differential Scanning Calorimetry (DSC) analysis identified a peak between 168.8 °C and 245 °C, with the peak temperature recorded at 214.5 °C, indicating the optimal calcination temperature for iron oxalate. This was confirmed through oven testing and X-ray Diffraction (XRD) analysis. The treated effluent exhibited a Chemical Oxygen Demand (COD) of 418 mg/L, with residual Fe and Pr concentrations significantly reduced to 5.7 mg/L and 4.3 mg/L, respectively. This approach demonstrates an efficient method for wastewater treatment and resource valorization, promoting sustainability in the recycling sector. Full article

Amorphous mesoporous magnesium carbonate (AMMC) materials were synthesized solvothermally using different magnesium oxide (MgO) precursors. These precursors were synthesized via the sol–gel method that employed various carboxylic acids (oxalic acid, citric acid, and maleic acid) as gelling agents. The specific type of carboxylic acid used was found to modulate the textural properties and CO₂ capture capability of the intermediate MgO, consequently regulating the textural and structural properties of the final AMMC materials. This solvothermal method offers advantages as it avoids the need for additives or harsh conditions. The capacity of AMMC materials to trap water was also evaluated. Full article

Despite the known association between calcium and magnesium in drinking water and stone risk, the difference in stone prevention of purified water remineralized with varying calcium-to-magnesium ratios (Ca:Mg) remains unclear. Objectives: This study investigates the impact of different Ca:Mg in the remineralization of purified water on calcium oxalate crystallization and renal injury. Methods: Sixty male Sprague-Dawley rats were induced calcium oxalate crystals by a sodium oxalate diet and divided into six groups, where they drank purified water with or without remineralized varying Ca:Mg (0.5, 3.4, 10, 20, 100). Serum and urine biomarkers of renal function, renal injury, mineral metabolism, bone metabolism, and urine calcium oxalate crystals were detected. Kidneys were isolated for pathological examination. Results: Findings showed that remineralization by 0.5 and 3.4 Ca:Mg significantly reduced urinary calcium oxalate crystallization, renal injury, and improved renal function, while extreme ratios (Ca:Mg over 10) showed no benefits. Conclusions: These results elucidate the pathophysiological effects of Ca:Mg in drinking water on renal health, particularly emphasizing the protective role of the 0.5 and 3.4 in inhibiting calcium oxalate crystallization and mitigating renal injury. It provides a quantifiable reference for purified water remineralization aimed at stone prevention. Full article

ZnO semiconductor-based photocatalysts are mainly studied for the elimination of toxic textile dyes. Metal-doped ZnO displays better performance for this purpose. Herein, Al-doped ZnO (Al–ZnO) was prepared using the mechanochemical calcination method with varying aluminum concentrations for the degradation of the persistent methylene blue (MB) dye. Various characterization techniques, including XRD, FTIR, FESEM, TEM, UV-DRS, and XPS, revealed the improved properties of 3% Al–ZnO in degrading the MB dye. It exhibits 96.56% degradation of 25 mg/L MB dye under 60 min of natural sunlight irradiation with a catalyst dose of 0.5 g/L at a natural pH of 6.4. A smaller particle size, a lower band gap energy of 3.264 eV, and the presence of oxygen vacancies and defect states all facilitate photocatalytic degradation. Radical scavenger experiments using ascorbic acid (for •O₂⁻), 2-propanol (for •OH), and diammonium oxalate (for h⁺) confirmed the crucial role of superoxide (•O₂⁻) and hydroxyl (•OH) radicals in the degradation mechanism. The achievement of 82.80% MB degradation efficiency at the 4th cycle validates the notable stability and excellent reusability of Al–ZnO. Full article