Tomato pomace, a major by-product of industrial tomato processing composed mainly of peels and seeds, represents a valuable source of bioactive compounds with potential nutraceutical applications. This study comparatively evaluated the apparent bioaccessibility of phenolic compounds and lycopene from tomato pomace using two distinct in vitro gastrointestinal digestion approaches: sequential phase sampling (R1) and cumulative digestion sampling (R2). A static digestion model including oral, gastric, and intestinal phases was applied to assess the release of bioactive compounds into digestive fluids. Total phenolic content was determined using the Folin–Ciocalteu method and expressed as gallic acid equivalents (GAE), while lycopene was quantified by UHPLC-DAD. Phenolic compounds showed the highest concentration in the oral phase (332.65±29.67 mg GAE L⁻¹), followed by the intestinal phase ((234.73±21.45 mg GAE L⁻¹), with the lowest value observed in the gastric phase (171.78±14.73 mg GAE L⁻¹). Lycopene bioaccessibility increased progressively during digestion, reaching 8.61% in the oral phase, 16.47% in the gastric phase, and 29.07% in the intestinal phase. The cumulative digestion fraction was lower (22.1%), suggesting partial degradation of lycopene and retention of carotenoids within the insoluble fiber fraction of the tomato pomace matrix. These results indicate that digestion conditions and matrix interactions significantly influence the release and apparent bioaccessibility of tomato-derived bioactive compounds.
It is an important task for modifying heterogeneous Fenton catalysts to effectively degrade organic pollutants in water. Most studies have modified heterogeneous Fenton catalysts through addition of other metal active species. Here, a series of Si-Fe/γ-Al2O3 (x, x = Si/Fe mass ratio per gram of support) catalysts were prepared via wet impregnation method, and the characterization results show that the addition of trace Si (x < 0.10) facilitated the dispersion of Fe species, thereby leading to an increase in the specific surface area, average pore size and pore volume of the catalysts. At the same time, trace Si addition can effectively improve the acid-base properties of the catalyst surface. All these changes may be beneficial to the catalytic degradation of the phenol simulated wastewater.
Comparative chemometric approaches based on raw artificial neural networks (RAW-ANN) and principal component analysis-artificial neural networks (PCA-ANN) were developed and applied to the simultaneous spectrophotometric determination of caffeine (CFN), propyphenazone (PRPN), and paracetamol (PRC) in a commercial ternary pharmaceutical formulation. The spectral overlap of the three components within the 220-300 nm region renders conventional spectrophotometric methods inadequate without prior separation. The proposed ANN-based models enabled direct analysis of raw UV spectral data without requiring any separation procedure over concentration ranges of 2.5-12.0 µg/mL (CFN), 3.0-12.0 µg/mL (PRPN), and 3.0-16.0 µg/mL (PRC). Both training approaches demonstrated satisfactory analytical performance, with mean recoveries ranging between 97% and 105%. In particular, PCA-ANN yielded relative standard deviations below 2.5%, indicating enhanced precision and predictive stability compared to RAW-ANN. Statistical evaluation confirmed the robustness and reliability of the developed models. The methods were successfully applied to the quantitative analysis of pharmaceutical tablets, demonstrating their suitability for routine quality control of complex multicomponent formulations.
In this study, iron oxide nanoparticles were produced and characterized using a green synthesis method with Robinia pseudoacacia fruits. The structural and functional properties of the nanoparticles were investigated using XRD, TEM/EDX, and FTIR analyses. The results indicated that the produced iron oxide nanoparticles had nanoscale particle sizes and exhibited a poorly crystalline (predominantly amorphous) structure according to XRD analysis. The comparative adsorption performance of the synthesized FeONPs and fruit powder in the removal of malachite green (MG), phenol red (PR) and methylene blue (MB) from aqueous solutions was evaluated. According to the results, the adsorption capacity followed the order MB> MG > PR. FeONPs exhibited consistently higher Qₑ values across all dye systems compared to the fruit powder. High removal efficiencies were obtained at low and moderate initial concentrations, while increasing the adsorbent dose enhanced the overall removal but resulted in a reduction in the adsorption capacity per unit mass. The obtained findings indicate that biosynthesized iron oxide nanoparticles can be used as an efficient and environmentally friendly adsorbent for eliminating environmental pollutants.
The increased discharge of synthetic dyes into aquatic ecosystems has caused significant environmental concerns, prompting the search for sustainable adsorbents. Sewage sludge, an abundant by-product of wastewater treatment facilities, offers the opportunity for dye removal within a circular economy paradigm. This study investigates the potential of raw dried secondary treated sewage sludge as an effective adsorbent for the removal of methylene blue, a cationic dye, from aqueous solutions. The adsorbent was characterized by Fourier transform infrared spectroscopy, field emission scanning electron microscopy, and Brunauer–Emmett–Teller surface analysis to evaluate its morphology, functional groups and textural properties. Batch adsorption experiments examined the effects of pH, initial dye concentration, adsorbent dosage, particle size, and contact time on the removal efficiency. Optimal conditions were observed at pH 9, with 0.5 g of sewage sludge (particle size 0.5 mm) in 50 mL of 10 mg/L dye solution and a contact time of 30 minutes. The adsorption equilibrium data conformed best to the Langmuir isotherm model, with a maximum monolayer adsorption capacity of 14.08 mg/g. Kinetic studies indicated that the adsorption process followed the pseudo-second-order model (R²=0.999), suggesting chemisorption as the predominant mechanism. The adsorbent also exhibited a pH-stabilizing behaviour, wherein the solution pH after adsorption shifted toward neutrality regardless of the initial pH, highlighting its suitability for practical wastewater treatment applications. The study demonstrates the potential of raw secondary treated sewage sludge as an eco-friendly adsorbent, aligning with sustainable wastewater treatment strategies.
Long ground resting of coins small denomination might affect their microstructure due to advanced corrosion. It is well known that cleaning of silver-copper alloy artifacts leads to a surface enrichment of the silver amount due to the partial removal of the copper grains which are more corroded. We found a półtorak issued in 1624 with abnormal characteristics like lower weight and dull sound when it is thrown on the solid surfaces. It resulted to be made of very high silver content about 97 wt. % according SEM-EDX correlated with XRD in great discordance with the common półtoraks from 1624 having about 70 wt.% silver. Advanced investigation of the abnormal półtorak reveals a porous internal structure indicating complete dissolution of β grains and copper sheets within the eutectic. All observation pleads for a progressive corrosion involving partial leaching of product through the wet resting ground which might ensure the dissipation of the corrosion-product and affecting deeper layers. Such dynamic-corrosion for 300 years might explain this intragranular corrosion which transforms an Ag-Cu hypereutectic alloy into almost pure silver. This preliminary hypothesis must be further investigated on larger półtoraks hoards which might have such abnormally corroded coins and on suspicious random finds.
In edible films with added plant extracts, the effects of the polymer matrix used and the production method on film performance have not yet been sufficiently clarified. Therefore, in this study, the quality parameters of starch-gelatin and chitosan-based edible films with added rhubarb (Rheum ribes L.), produced by two different methods, were comparatively examined. The films were characterized in terms of thickness, water solubility, mechanical properties, water vapor permeability, optical properties, color parameters, antioxidant capacity, biodegradability, and structural properties. The results showed that the film properties changed significantly depending on both the polymer matrix used and the rhubarb extract concentration. Starch-gelatin-based films exhibited higher water solubility and flexibility, while chitosan-based films showed higher mechanical strength and better water vapor barrier properties. Rhubarb addition significantly increased the antioxidant potential of the film-forming mixtures in both methods. Color analyses revealed that the films darkened with increasing rhubarb concentration. SEM and FT-IR analyses showed that rhubarb addition caused physical changes in the film structure but did not alter the chemical structure. Chitosan-based films with rhubarb addition may be considered as a potential alternative for active and sustainable food packaging applications.
Vitamin B6 (pyridoxine, PN) released from anthropogenic and biogenic activities can influence the chemical self-purification of surface waters through its photochemical transformations. The present study aimed to investigate the kinetics and mechanisms of pyridoxine photodegradation under conditions that partially simulate the natural environment (pH ~7, aerated medium) using simulated solar irradiation. Three model systems were investigated: (1) PN–hν; (2) PN–H2O2–hν; (3) PN–H2O2–Cu(II)–hν, using direct spectrophotometry (λ = 328 nm). The kinetic parameters determined included partial reaction orders (using the van’t Hoff method), effective rate constants, and half-lives (τ₁/₂). Direct photolysis of PN follows a partial reaction order of 0.2 with respect to [PN], with k = (5.38±0.26)·10-4 s-1 and τ₁/₂ = 21±0.5 min. However, the low quantum yields (7.31–10.70)·10-3 indicate that direct photolysis of vitamin B6 is negligible under natural aquatic conditions. In the presence of H2O2, the partial reaction orders are 0.3 (PN) and 0.7 (H2O2), with W = k·[PN]0.3·[H2O2]0.7, k = (3.69±0.11)·10-4 s-1 and τ₁/₂ = 31.1±0.30 min. For PN–H2O2–Cu(II), the partial reaction orders are 0.2 (PN), 0.4 (H2O2), and 0.3 (Cu2+) with k = (3.91±0.17)·10-4 s-1, and τ₁/₂ = 29.2±0.53 min. In conclusion, PN undergoes measurable photodegradation under simulated natural conditions.
Polychlorinated biphenyls (PCBs) are persistent organic pollutants that accumulate in soils, making their reliable determination in this complex matrix analytically challenging. This study presents the validation of a method based on ultrasound-assisted extraction (UAE) coupled with gas chromatography–mass spectrometry operating in selected ion monitoring mode (GC-MS-SIM) for the determination of 19 PCB congeners in soil samples. Method performance was evaluated in terms of selectivity, linearity, limits of detection and quantification, precision, and accuracy, demonstrating robust analytical performance for trace-level PCB determination. The obtained LODs ranged from 0.05 to 0.78 ng•g-1. The validated method was applied to 92 soil samples collected from the Copșa Mică area (Romania) at two depth intervals (0–5 cm and 5–20 cm). Comparable ΣPCB concentrations were observed between the two soil layers, indicating a relatively uniform vertical distribution. Congener-specific analysis revealed the predominance of PCB 118 and PCB 187, while homologue distribution patterns were dominated by penta- and hepta-CBs. These results confirm the suitability of the validated method for PCB determination in soils and provide insight into congener- and homologue-level compositional patterns in real environmental samples.
High-fructose corn syrup (HFCS) is produced industrially by the immobilized glucose isomerase Sweetzyme IT (from Streptomyces murinus), one of the most widely used biocatalysts in the food industry. Although its individual operating parameters are well established, simultaneous interactions between operational variables over time have rarely been systematically quantified. In this study, a two-level full factorial design modeled the combined effects of initial glucose concentration, temperature and Mg2+ cofactor concentration on the process. Reaction progress was followed polarimetrically through a dedicated glucose-fructose calibration; concurrent refractometric monitoring proved insensitive due to total dissolved solids conservation. The regression models (R2 > 0.99) identified temperature as the dominant operational factor. Incorporating reaction time as a factor revealed a significant temperature × time interaction and a shift of rate control from initial substrate concentration to temperature near equilibrium. A maximum conversion of 45.98 % (close to the thermodynamic equilibrium of the reaction) was obtained at 0.2 M glucose, 60 °C and 1.5 mM Mg2+ after 24 h. A comparative screening of divalent cations confirmed MgSO4·7H2O as the superior chemical activator, over Ni2+, Mn2+, Cu2+ and Ca2+ with Ca2+ among the poorest, consistent with its known inhibitory role. This study establishes a reliable mathematical approach that can be extended to predict and optimize other complex bioprocesses.
A plasticized polylactic acid (PLA) composite incorporating zinc oxide (ZnO) was synthesized via melt mixing and hot pressing. The physicochemical and preliminary microbiological properties of the composite were systematically evaluated. ZnO powder, produced through precipitation and calcination, was characterized using dynamic light scattering and nitrogen sorption analysis. The PLA composite, comprising PLA, Proviplast 2624, Span 60, and ZnO, was subjected to tensile and flexural testing, oxygen and water vapor barrier measurements, water uptake analysis, contact angle assessment, and Atenuated Total Reflectance – Fourier Transform Infrared spectroscopy (ATR-FTIR). The ZnO powder exhibited a broad, aggregate-dominated particle-size distribution and a moderate specific surface area. The composite displayed reduced stiffness and strength relative to neat PLA, indicating effective plasticization. Preliminary microbiological assays indicated decreased recovery of the tested microorganisms under the specified conditions.
The present study evaluated the phytochemical composition and antioxidant activity of some hydroalcoholic extracts of Geranium robertianum. Total polyphenol content (TPC) and total flavonoid content (TFC) were estimated using colorimetric methods, while antioxidant activity was evaluated by DPPH and ABTS assays. High performance thin layer chromatography (HPTLC) was performed to obtain the fingerprints of samples and for preliminary investigation of the presence of isoflavonoids in their composition. The leaf extract exhibited the highest TPC (9.47 ± 0.66 mg gallic acid equivalents/mL), TFC (736.66 ± 9.38 mg rutin equivalents/mL), and showed the strongest antioxidant activity in both DPPH (12.55 ± 1.01 mg vitamin C equivalents/mL) and ABTS (5.63 ± 0.34 µmol Trolox equivalents/mL) assays. Flowers extract demonstrated considerable levels of phenolic compounds and antioxidant activity. The chromatographic fingerprints are characteristic of each analyzed part of the plant. The extracts purchased from the market have fingerprints different from those prepared in the laboratory. Also, the obtained fingerprints highlight the possible presence of isoflavonoids in the composition of the analyzed extracts. These findings demonstrate that leaves and flowers of Geranium robertianum represent valuable source of natural antioxidants and provide new information regarding the phytochemical characteristics of commercial Romanian preparations.
The honey samples analysed in this study were obtained from a private producer located in Olt County who requested a qualitative characterization of his products depending on honey sources. The first stage of the investigation involved key physicochemical parameters: moisture content, free and total acidity, initial and total invert sugars, sucrose levels, and the presence of hydroxymethylfurfural (HMF) and metallic elements. Differential Scanning Calorimetry (DSC) was additionally used to characterize the thermal properties of the samples. The final part of the study examines the rheological behavior of four honey varieties under different temperature conditions, providing insights into their flow characteristics and structural stability. All the obtained values fall within the ranges established by European regulations, except for Pb; the exceedances reflect the influence of anthropogenic factors in the mentioned region.
Recently, salinity gradient energy – known as blue energy – has sparked the interest of researchers in identifying a new source of renewable energy, available at the contact between river water and seawater. In this paper, which is a mini-review of the salinity gradient energy harvesting, the appreciable potential of this energy source is emphasized by calculating the thermodynamic effect of mixing a water of high salinity, which simulates seawater, with water of low salinity, characteristic of rivers. Unfortunately, this potential of salinity gradient energy is difficult to exploit due to technical limitations. In such circumstances, the seawater-river water system was approached as an electrochemical thermodynamic system, at the interface of which an electric potential difference occurs. In the simplest case, this is a diffusion potential, evaluated based on Henderson equation. The value of the diffusion potential is low (about 20 mV) because the interface between these two media is crossed by both cations and anions. If, however, the two media of different salinity are separated by an ion exchange membrane, there is a much larger potential difference between them (about 100 mV), called membrane potential, which can be capitalized using a concentration cell. Moreover, the main methods applied so far for the recovery of the salinity gradient energy are highlighted: pressure retarded osmosis, reverse electrodialysis and capacitive mixing methods.
The free-base, symmetrically substituted 5,10,15,20-tetrakis(3-hydroxyphenyl)-porphyrin was the subject of a study combining computational and experimental analysis, with an emphasis on the molecule’s water-splitting electrocatalytic characteristics. Ab initio and DFT methods were used to investigate the porphyrin’s structural and electronic properties. The water-splitting experiments, performed in solutions with different pH values, were carried out with porphyrin-based electrodes that were modified using different strategies. The electrode manufactured by drop-casting a catalyst ink containing the porphyrin and carbon black on a graphite substrate displayed an overpotential value for the oxygen evolution reaction of 0.595 V vs. RHE and a Tafel slope of 0.337 V/dec in a neutral environment. Data acquired during the electrochemical experiments were used to perform statistical analysis. The correlation analysis indicated a significant association between pH and overpotential. The combined study improves the current scientific understanding of the porphyrin’s properties and shows the effect of the electrode modification strategies on its water-splitting electrocatalytic activity. The Supplementary Material file can be downloaded at: https://doi.org/10.5281/zenodo.20571954
This work focuses on the comparative description of convective thin-layer drying of celery leaves and stalks at 40, 50 and 60oC, respectively. Close to 100% moisture loss was recorded, yet total process time shortens at elevated temperatures. The adjusted determination coefficient, the root mean square error and the hybrid fractional error deviation, respectively, were simultaneously employed as selection criteria for the most suitable kinetic model. The empirical parabolic model was chosen to describe drying kinetics of both plant parts. Its parameters and their temperature dependence were quantified. Calculated drying parameters reflect the results of ANOVA testing. Effective water diffusivity coefficients are 3 orders of magnitude higher for stem and its drying activation energy is 34% lower. Specific energy consumption values prove that drying of stems is more energy efficient than that of leaves.
The development of methods for latent fingerprints visualization is still attractive considering that there is no approach that is universal for all types of fingerprints and substrates. A thorough understanding of the visualization mechanism is crucial for expanding methods application and making them practical for real case scenarios. In this research, nitrogen dioxide (NO2) treatment, previously limited to thermal paper substrates, is expanded towards visualization of latent fingerprints on various non-porous and porous substrates by introduction of pre-treatment with tetra-n-butylammonium iodide (TBAI). The visualization processes were studied using Raman, UV-Visible, FTIR and 1H NMR spectroscopy, combined with various validation experiments. The results show that formation of molecular iodine (I2), generated by reactions between NO2 and TBAI, plays a key role in the visualization mechanism. The as-generated I2 further reacts with excess TBAI, producing tetra-n-butylammonium triiodide (TBAI3). TBAI3 is a dark colored compound that provides the dominating contrast of the visualized fingerprint. Besides reactant, TBAI resembles a role of a phase-transfer catalyst that enables NO2 to penetrate deeper into fingerprint’s residue and to react with the fatty acid esters producing intrinsically colored nitro-compounds that additionally contribute towards fingerprints visualization effect.
This study optimized the microwave drying of olive leaves by integrating mathematical modeling and proposing a novel drying model, along with a comprehensive analysis of energy efficiency and bioactive compound preservation. Experiments were conducted at microwave power levels ranging from 100 to 1000 W, assessing drying kinetics, energy efficiency, and retention of bioactive compounds. The optimal power of 700 W achieved a drying time of 21 minutes while preserving key bioactive compounds, with TPC, TFC, and antioxidant activity reaching 108.79 mg GAE/g DM, 12.12 mg RE/g DM, and 23.25 mg GAE/g DM, respectively. Several mathematical models from the literature were evaluated, and the Logarithmic, Modified Henderson-Pabis II, and Hii et al. models showed excellent agreement with the experimental data (R-2 > 0.99). The proposed new model also demonstrated strong predictive accuracy, with high R2 values and low root mean square error and reduced chi-square (chi(2)). The lowest specific energy consumption was 0.236 & times; 10(5 )MJ/kg H2O, accompanied by the highest energy efficiency. These results demonstrate that intermediate microwave power provides an optimal balance between energy efficiency, processing time, and bioactive compound preservation, highlighting both practical and economic advantages for olive leaf drying.
Water Quality Index (WQI) approach has been utilized in this study to evaluate groundwater quality in suburban areas of Hadapsar, Pune, India. From borewells and open wells in Hadapsar and nearby area. Thirty-two groundwater samples were gathered. Physicochemical analysis revealed that calcium was the major cation, followed by magnesium, sodium, and potassium, while bicarbonate was the dominant anion. For Mg, K, electrical conductivity, total dissolved solids, some samples have been above allowable levels. 68.75% of samples were of good quality for drinking, according to WQI values, while 28.12% of samples have been of outstanding quality. Indicators of irrigation water quality, including the MH (Magnesium Hazard), SSP (Soluble Sodium Percentage), Percent Sodium (%Na), RSC (Residual Sodium Carbonate), and SAR (Sodium Adsorption Ratio), demonstrated that groundwater was suitable for irrigation with negligible risks related to sodium, salinity, and carbonate contents. This research highlights the significance of regular monitoring as well as analysis of groundwater resources in rapidly urbanizing areas to ensure sustainability and safety of drinking and irrigation purposes. These results offer important new information about pollution control methods, sustainable urban planning, and the management of water resources in Pune's expanding periphery.
. Cancer continues to be a primary cause of death globally, prompting the investigation of effective natural therapeutic agents. Mangifera indica L. (mango) leaves are notable for their abundant bioactive compounds, especially polyphenols. This study investigated the extraction, purification, and anticancer properties of polyphenolic compounds from M. indica L. leaves cultivated in Iraq. The research employed systematic extraction procedures using methanol followed by purification through Sephadex LH60 column chromatography. Phytochemical analysis and Highsignificant concentrations of bioactive compounds, with mangiferin (49.8 mg/L) being the predominant polyphenolic constituent, alongside other compounds including apigenin (40.5 mg/L), ferulic acid (36.5 mg/L), and kaempferol (28.9 mg/L). The cytotoxic potential of methanolic extract of M. indica diphenyltetrazolium bromide (MTT) assay. The results demonstrated that the cytotoxic effect is dependent on dose, with maximum cell death (68.33%) observed at 1000 & micro;g/mL concentration. The extract exhibited a moderate cytotoxic effect with a half-inhibitory concentration (IC50) value of 132.4 & micro;g/mL. The observed anticancer activity is attributed to the synergistic effects of various polyphenolic compounds, particularly mangiferin, which triggers apoptosis through both intrinsic and extrinsic pathways. These findings suggest that M. indica leaf extract could be a promising source of natural anticancer agents.
