Physicochemical Research Articles

Assessment of immunogenicity and protective efficiency of multi-epitope antigen-loaded in mannan decorated PLGA nanoparticles against tuberculosis

The antigen-targeting to dendritic cells (DCs) has gained increasing attention as the potential approach for immunotherapy in recent years due to the ability of DCs to regulate innate and adaptive immunity. In the present study, the immunogenicity and protective efficiency of mannan-decorated PLGA nanoparticles (NPs) loaded with multi-epitopes mycobacterium tuberculosis antigen (HspX-Ppe44-EsxV) were evaluated as a targeted delivery system to DCs. For this purpose, PLGA nanoparticle formulations were prepared and subsequently decorated by mannan. The physicochemical properties and level of mannan incorporation, as well as encapsulation efficiency and antigen release, were assessed. The potential of formulated NPs for antigen targeting to DCs, and immunogenicity against tuberculosis (TB) were investigated using immunofluorescence assay and in-vivo experiments. Mannan incorporation enhanced the uptake of fusion-loaded PLGA by DCs. The cytokine and antibody assays demonstrated that mannosylation of NPs and BCG-primed mice boosted by mannan-PLGA could significantly elevate Th1-biased immune responses relative to the BCG and non-modified PLGA NPs. Our findings also proved that the mannosylated vaccine in the presence of CpG could evoke Th1 and Th17 responses with appropriate protective efficiency against TB in mice. This result illustrated that the active targeting of DCs by mannan-PLGA NPs could induce a proper anti-tuberculosis response, which is essential for protection against tuberculosis.

The formation of protein coronas and the interaction of soy protein isolate and whey protein isolate with starch nanoparticles

The influence of food components on the physicochemical properties and biological responses of nanoparticles is pivotal. Since soy protein isolate (SPI) and whey protein isolate (WPI) are commonly used as plant and animal proteins in food, it is imperative to gain comprehensive knowledge of the interaction between SPI/WPI and nanoparticles. Accordingly, we examined the adsorption of SPI and WPI onto starch nanoparticles (SNPs) and their associated interactions. SNP aggregation was observed in the SPI/WPI, and coronas formed around the surfaces of the SNPs. The binding of the protein isolates reduced the zeta potential of the SNPs from −10.34 to −26.5 mV for the SPI and to −21.37 mV for the WPI. However, mixing the SNPs with the protein isolates did not alter the microenvironment of aromatic amino acids and had no substantial impact on the secondary structure of the proteins. Thermogravimetric analysis revealed that the formation of SPI/WPI coronas enhanced the thermal stability of the SNPs. Isothermal titration calorimetry indicated that the adsorption of the SPI and WPI onto the SNPs was driven primarily by weak van der Waals forces and hydrogen bonds. This study facilitates the predicting of organic nanoparticle behaviours in complex food matrix and human gastrointestinal environments.

Hydrothermal-calcination synthesis of lithium orthosilicate microspheres for high-temperature CO2 capture

In recent years, the Li4SiO4 adsorbent has become a promising candidate for high-temperature CO2 capture. The fabrication of micro-structured Li4SiO4 could enhance the capture performance effectively. However, there exists a conflict between the purity and the morphology of prepared micro-structured Li4SiO4. This study proposed a novel hydrothermal-calcination method, which could produce Li4SiO4 microspheres with great morphology and relatively high purity. The physicochemical properties, CO2 capture performance and forming mechanisms of Li4SiO4 microspheres are evaluated and investigated systematically. It is found that the hydrothermal process could fabricate micro-spherical LiOH@Li2SiO3 precursor, which was further converted to Li4SiO4 microspheres during the subsequent calcination process. The LiOH@Li2SiO3 precursor could not only maintain the microstructure but also reduce the Li4SiO4 generation temperature, thus improving the morphology as well as the purity of obtained Li4SiO4 microspheres. As a result, the adsorbents could reach a CO2 capture capacity of 0.167–0.222 g/g within 30 min's adsorption under 15 vol.% CO2, and their cyclic stability are diverse depending on the used calcination temperatures. The hydrothermal-calcination contributes to the future preparation of high-performance Li4SiO4-based CO2 adsorbents.

Self-Assembled Hydrogel Based on (Bio)polyelectrolyte Complex of Chitosan–Gelatin: Effect of Composition on Physicochemical Properties

Taking into account the trends in the field of green chemistry and the desire to use natural materials in biomedical applications, (bio)polyelectrolyte complexes ((bio)PECs) based on a mixture of chitosan and gelatin seem to be relevant systems. Using the approach of self-assembly from the dispersion of the coacervate phase of a (bio)PEC at different ratios of ionized functional groups of chitosan and gelatin (z), hydrogels with increased resistance to mechanical deformations and resorption in liquid media were obtained in this work in comparison to a hydrogel from gelatin. It was found that at z ≥ 1 a four-fold increase in the elastic modulus of the hydrogel occurred in comparison to a hydrogel based on gelatin. It was shown that hydrogels at z ≈ 1 had an increased sorption capacity and water sorption rate, as well as increased resistance to the in vitro model environment of phosphate-buffered saline (PBS) solution containing lysozyme at 37 °C. It was also shown that in PBS and simulated gastric fluid (SGF) solutions, the effect of the polyelectrolyte swelling of the hydrogels was significantly suppressed; however, at z ≥ 1, the (bio)PEC hydrogels had increased stability compared to the samples at z < 1 and based on gelatin.

Green-Synthesis of CuO and Ce-Doped CuO Nanoparticles Using Aqueous Extract of Yam Peel and their Antimicrobial Properties

The rise of drug-resistant microbes presents a critical global health challenge in the 21st century, necessitating the development of potent antimicrobial agents with broad-spectrum activity. Therefore, in this study, we explored the antimicrobial activity of copper oxide (CuO) and cerium-doped CuO (Ce-doped CuO) obtained through a facile green synthesis approach. The nanoparticles were synthesized using aqueous extract of Dioscorea spp (yam peel) and characterized for their physicochemical properties using X-ray diffraction (XRD), Fourier-transform infrared spectroscopy (FTIR), electron microscopy, and UV-Vis spectroscopy. Their antimicrobial efficacy was tested against three bacterial strains—Enterococcus faecalis, Escherichia coli, and Listeria monocytogenes—and three fungal strains—Aspergillus niger, Mucor mucedo, and Penicillium chrysogenum. The results demonstrated that cerium doping significantly altered the physicochemical properties of CuO, leading to enhanced antimicrobial activity. The antibacterial zone of inhibition ranged from 7.50 to 16.55 mm for CuO and 11.80 to 19.50 mm for Ce-doped CuO. For antifungal activity, the minimum inhibitory concentration (MIC) ranged from 0.25 to 0.30 mg/mL for CuO and 0.025 to 0.03 mg/mL for Ce-doped CuO. Notably, the Ce-doped CuO nanoparticles exhibited antimicrobial effects comparable to standard antibiotics. These findings highlight the potential of green-synthesized Ce-doped CuO nanoparticles as effective antimicrobial agents. By leveraging green synthesis and elemental doping, this study offers a promising solution to combat a wide spectrum of infectious pathogens.

Nanoparticles for treatment of cadmium-contaminated cocoa-growing soils and beans: Performance on metal immobilization and removal.

Some areas of tropical soils where cocoa grows contain high cadmium (Cd) concentrations. The cocoa plant's need for nutrition causes the reticular system to uptake the toxic metal, translocate it, and accumulate it in roots, stems, and other edible parts such as cocoa beans and shells, threatening the health of cocoa consumers. To cope with this difficulty, different treatments have been applied to cadmium-contaminated soils, but they showed limited success. In this study, we prepared multicomponent nanoparticles (MCNPs) to treat cocoa soils in fixed-bed columns and field tests. Also, MCNPs were mixed with two varieties of cocoa beans, CNN51 and Fino de Aromain, during the fermentation, aiming to capture the cadmium. Our field investigations began by collecting soil samples from three Ecuadorian cocoa-producing farms to determine their physicochemical properties, cadmium, and iron contents. A few weeks later, a home-built prototype was installed in a cocoa plantation to fabricate the nanomaterials using commercial-grade chemicals and rainwater. Scanning Electron Microscope (SEM) images showed MCNPs with an average size of 65.21 nm and the formation of chain-like aggregates. In contrast, MCNPs size was 76.6 nm, measured with Dispersed Light Scattering (DLS). The chemical composition of MCNPs was 90.7% Fe0 and 1.81% sulfur (S), analyzed by energy dispersal X-ray (EDX) and confirmed by X-ray diffraction (XRD) spectrometer measurements. Regarding the treatments, for the fixed-bed column tests, 0.28-1.08 L/kg was dosed into the soil, while for field treatments, 250, 500, and 835 mL/min MCNPs were injected in soil areas of 5 m2 surrounding each cocoa tree (0.5-4.5 mg MCNPs/kg soil) at depths between 0 and 5 cm. Test results revealed that the procedure applied in the field did not reproduce the metal’s immobilization (∼22%) as in the fixed-bed columns (∼80%). Moreover, cadmium removal was ∼ 20% and ∼75% after treating CCN51 and Fino de Aroma cocoa beans with 0.112 kg MCNPs/kg in the fermentation on-site and 0.034 kg MCNPs/kg in the laboratory. In this study, the size and chain-like aggregates of MCNPs notably influenced the field treatments as they precluded the filtration of MCNPs downwards. However, immobilizing cadmium could be more effective in soils with higher concentrations of the metal and multicomponent nanoparticles of smaller size, expanding our research scope and offering a practical solution to pollution issues in cocoa-growing regions.

Insights into the photosensitivity and photobleaching of dissolved organic matter from microplastics: Structure-activity relationship and transformation mechanism

Revealing the structure-activity relationship between physicochemical properties and photoactivities of microplastic dissolved organic matter (MPDOM) is significant for understanding the environmental fate of MPs. Here, we systematically analyzed the physicochemical properties and molecular composition of DOM derived from MPs including polystyrene (PS), polyethylene glycol terephthalate (PET), polyadipate/butylene terephthalate (PBAT), polylactic acid (PLA), polypropylene (PP), and compared their photosensitivity and photobleaching behaviors. Results indicated that PSDOM and PETDOM had more similar properties and compositions, and showed stronger photosensitivity and photobleaching effects than PBATDOM, PLADOM and PPDOM. The [3DOM∗]SS and [1O2]SS varied in the range of 0.31-13.03 × 10-14 and 1.71-5.49 × 10-13M, respectively, which were within the reported range of DOM from other sources. The SUVA254, HIX, AImodwa, Xcwa and lignin/CRAM-like component showed positive correlation with the [3DOM∗]SS, [1O2]SS and Φ3DOM*. The negative correlation between E2/E3 and [3DOM∗]SS was due to the higher proportion of low-molecular weight components in MPDOM. The lignin/CRAM-like component was identified to be the crucial photobleaching-component. The lignin/CRAM-like in PSDOM showed a deepened oxidation degree, while its change trend in PETDOM was from unsaturated to saturated. These findings provide new insights into the relevant photochemical fate of MPDOM.

A comparative study on utilization of different plant-derived nanomucilage as a fat replacer in yogurt: Product optimization, physicochemical attributes, shelf-life evaluation, and consumer perception with market orientation

This study investigated the utilization of various plant-derived sources for the extraction of nanomucilage as a fat substitute in yogurt production. Colocasia esculenta rhizome mucilage (CEM), Cordia dichotoma fruit mucilage (CDM), and Psyllium husk mucilage (PHM) were extracted using different extraction process and spray drier was utilized to acquire nanomucilage with nano-scaled particles (100–300 nm). Seven different types of yogurts were prepared with the addition of varied mucilage concentrations (1–10 % w/v). Results showed that yogurt with 4.5 % PHM exhibited suitable viscosity, higher water holding capacity, and reduced syneresis over the 16 days of storage. Furthermore, selected sample revealed similar physicochemical, textural, and color attributes as compared to control full fat and skimmed milk yogurt. Moreover, this study revealed that consumers highly accepted mucilage formulated yogurt, with a mean score of 97.16 ± 1.58 %. Overall, nanomucilage can potentially utilized as a sustainable biomaterial for the production of low-fat yogurt.

Investigation on the interfacial and emulsion stabilized behavior of dextran/ferritin/resveratrol composite nanoparticles

Glycation of ferritin provides a viable approach to enhance its physicochemical and functional properties. However, there is limited research on the interfacial adsorption properties of glycated ferritin-based colloidal particles. Therefore, this study selected recombinant human H-chain ferritin (rHuHF), rHuHF encapsulated with resveratrol (rHuHF–Res), and rHuHF–dextran glycoconjugates loaded with resveratrol (Dex–rHuHF–Res) as emulsifiers to investigate their interfacial adsorption properties. The results revealed that Dex–rHuHF–Res exhibited superior emulsifying properties and rheological behavior. It also increased the hydrophobicity of the microenvironment around Tyr and Trp residues, while hydrogen bonds, hydrophobic force, and salt bridge were identified as the most important intermolecular interactions. Dex–rHuHF–Res exhibited the biggest contact angle and lowest interface tension, which further reduced the diffusion (Kdiff) from the aqueous phase to the interface but promoted the penetration (Kp) and rearrangement (Kr) rates at the interface. Meanwhile, the emulsion stabilized by Dex–rHuHF–Res displayed excellent freeze-thaw stability, and Dex–rHuHF–Res can be more densely accumulated at the O/W interface to form an interface layer. These findings highlight the promising application of glycated ferritin in stabilizing Pickering emulsions, and deepen our understanding of the interplay among particle interaction, interface adsorption properties, and emulsion stability.

Physicochemical and processing properties and in vitro fecal fermentation characteristics of Prunus cerasifera Ehrhart polysaccharide

Prunus cerasifera Ehrhart fruit polysaccharide (PCP) was obtained after determining the optimal extraction conditions for complex enzyme-assisted hot buffer extraction based on single-factor experiments and response surface methodology, followed by characterization of its physicochemical, processing, rheological, and biological properties. PCP was a thermally stable carbohydrate with acidic functional groups and a molecular weight of 1398.69 kDa, exhibiting smooth, dense flake and honeycomb network microstructures. PCP had favorable hygroscopicity, moisturizing properties, water and oil-holding capacity, proemulsification capability, and in vitro antioxidant activity. The apparent viscosity of PCP in an aqueous system was dependent on concentration and temperature and was altered by the variety and amount of metal ions added; its aqueous solutions exhibited strong viscosity and hydrogel-forming tendencies at suitable concentrations, along with excellent hydrogel properties after gelation. Furthermore, PCP favored the growth of beneficial gut microbiota and associated microbes responsible for producing essential short-chain fatty acids. Overall, PCP displayed high potential as a multifunctional additive for applications in the food, pharmaceutical, and cosmetic industries.

Effect of different drying techniques on the physicochemical and nutritional properties of Moringa oleifera leaves powder and their application in bakery product

The study analyzed the influence of drying methods and conditions on the quality of moringa leaves powder (MLP) and determined the optimal MLP to wheat flour ratio for cake development. Cabinet drying temperatures enhanced mass and tapped density but reduced the angle of repose, water retention capacity, and oil retention capacity. The moisture content of cabinet-dried MLP samples exhibited a substantial reduction as temperature is increased. The crude protein and fat content increased with increasing drying temperatures. Vacuum dried samples had the highest fiber content (16.62g/100g). Cabinet dried samples at 60°C had the highest ash content (8.37g/100g). The energy obtained from MLP dried in a cabinet at 70°C was the highest (383.33 Kcal/kg). The mineral composition of MLP in vacuum drying showed the largest growth. Sun drying was less efficient in preserving antioxidant components, while vacuum drying was the most successful. But sun drying was more cost effective than that of other drying methods. The composition of cakes formulated from MLP and wheat flour blends exhibited notable variations characterized by an increase in protein content and decrease in carbohydrate content with the incorporation of MLP. 5% and 10% MLP enriched cakes showed the best customer acceptance.

Enhancing cherry tomato packaging: Evaluation of physicochemical, mechanical, and antibacterial properties in tannic acid and gallic acid crosslinked cellulose/chitosan blend films

The aim of this work was to study the characteristics of composites fabricated from cellulose (CL) and chitosan (CS) blends that were reinforced with different tannic acid (TA) and gallic acid (GA) concentrations. The structure and antibacterial activity of CL/CS composite films were investigated with the addition of TA and GA. The composite films were subjected to mechanical, water contact angle (WCA), Fourier transform infrared spectroscopy (FTIR), X-ray diffraction (XRD), Scanning electron microscopy (SEM), and antibacterial activity tests. The FTIR results and the uniform dense SEM images confirmed the interaction of TA and GA with the CL/CS blends. The water vapor transmission rate (WVTR) of films with 5 wt% TA and GA improved by 23.02 %. The tensile strength of the CCTA-3 film was 27.67 MPa, demonstrating higher tensile properties compared to films made from CL and CS blend film (13.20 MPa). The prepared films also showed increased resistance to moisture and water, as indicated by their higher water contact angle (WCA) values (59.43°). The antibacterial activity of the films was effective against food-borne bacteria such as S. aureus and E. coli due to the addition of TA and GA. The shelf-life of cherry tomatoes increased by approximately 15 days when covered in CCTA-3 instead of polyethylene film. Based on the results, CL/CS blend films containing TA could be beneficial for use in active food packaging.

Quantitative Structure-activity Relationship (QSAR) Modelling of Indomethacin Derivatives using Regression Analysis.

Indomethacin is a non-steroidal anti-inflammatory drug (NSAID) used for medication to reduce fever, spondylitis, or shoulder pain. It mainly works by the inhibition of prostaglandins, the endogenous signaling molecules. Fifteen indomethacin derivatives have been analyzed in relation to their physicochemical and molecular properties. Two-dimensional (2D) structures of fifteen indomethacin derivatives were drawn using the ACD Lab Chem Sketch version. Most of the topological parameters, such as wiener index (W), mean wiener index (Wa), Balaban indices (J), Balaban centric index (BAC), and molecular connectivity (χ), were calculated by using E Dragon software. The most common molecular file formats accepted in EDragon software were SMILES notations created online by Babel software and 2D structures of various derivatives, which were converted into 3D optimized structures using online CORINA, provided by Molecular Networks GMBH. 3D structures of compounds were also drawn on Gauss View software for calculations of various density functional theory (DFT) based quantum chemical descriptors, such as total energy (TE), softness (S), hardness (η), chemical potential (μ), highest occupied molecular orbital energy (HOMO), and lowest unoccupied molecular orbital energy (LUMO). All species were fully optimized in the gas phase with a 6-31+G* basis set. The harmonic vibrational frequency calculations were used to confirm that the optimized structures were minima, as characterized by positive vibrational frequencies. Combinations of various descriptors, such as D, ID, IOR, Log P, Mr, Mv, Mw, Pc, BAC, Pz, St, W, Wa, 0χ, 1χ, 2χ,3χ,4χ, 5χ, and Xeq have been found to be significant for modeling of activity. QSAR model no. 2: pIC50= -20.605 (±6.600) IOR - 0.747 (±0.454) I1 -5.083 (±3.478) Xeq + 51.647 optimized with empirical parameters with high statistical quality (R= 0.921, R2=0.848) was found to be the best model obtained. The QSAR model obtained suggests that substituents with a lesser value of the index of refraction and less electronegative groups were favourable for the activity, whereas indomethacin derivatives with a CH2CH2NHCONH(CH2)3ONO2 group at R1 position were unfavourable for the activity. The results were critically discussed based on regression data and cross-validation techniques. Pogliani factor Q and the results of the LOO (leave-one-out) method confirmed the reliability and predictability of the proposed models that could be highly beneficial for the future designing of new analogues with higher potency.

Development and characterization of functional beverage based on soursop (Annona muricata L.), inulin, and whey powders

This study aimed to develop and evaluate "functional" beverages made from a blend of soursop (Annona muricata L.), whey, and/or inulin using a selected Lactobacillus strain. To achieve this objective, various steps were conducted: 1) analysis of soursop powder in its chemical proximal, physicochemical, and antioxidant properties, 2) selection of Lactobacillus species with the highest ability to grow in a formulated beverage, 3) evaluation of several beverages based on soursop, whey, and/or inulin in their physicochemical characteristics, antioxidant capacity, probiotic survival, and sensory acceptance to choose the one with the highest quality characteristics, 4) analyze the effect of storage time (20 days at 4°C) on the quality characteristics of chosen beverage. The results indicated that soursop contains functional compounds like dietary fiber (2.41 %), total phenolic compounds (370.26 mg GAE/100 g), and antioxidant capacity (2260.72 mg Trolox/100 g). Although LAB grew (6.88-7.73 log cycles) in formulated beverage, L. acidophilus presented the highest microbial count (7.73 log cycles, p < 0.05) after 12 h of fermentation; therefore, it was used to ferment soursop solutions. On the other hand, among fermented beverages, the one formulated with soursop, whey, and inulin presented the highest probiotic growth and antioxidant capacity. Therefore, it was analyzed during the storage at 4°C. After storage time, the fermented beverage maintained a high probiotic count (> 7.5 log cycles) and antioxidant capacity (even more than at the beginning of storage), with a good sensory acceptance (like it). Thus, this study successfully developed a probiotic beverage using soursop, whey, and inulin, which have favorable functional properties and sensory acceptance.

The physicochemical characteristics and antioxidant attributes of propolis sourced from various regions in Iran

Honey, beeswax, and propolis have long been recognized for their significance in the treatment and prevention of diseases. Numerous studies have demonstrated their antioxidant properties, making it crucial to investigate in depth their physicochemical, antioxidant, and microbial characteristics. The objective of this research was to examine the characteristics of propolis sourced from different areas within Iran. Propolis samples were obtained from beehives located in Sarab, Maku, Quchan, Neka, Qom, and Sanandaj regions for analysis. The physicochemical and antioxidant properties and mineral content of propolis were evaluated. Obtained data showed that Quchan propolis has the highest total antioxidant level, and the lowest amount was found for Qom samples (0.848 vs 0.531 %). Qom propolis samples had the highest aluminium, calcium and magnesium content among region samples. At a concentration of 1% propolis, the Qom exhibited significant antibacterial efficacy against E. coli and S. aureus. The Quchan samples had more antibacterial activity against E. coli at a level of 2% propolis. The results of this study showed that the chemical composition, mineral content and antibacterial properties of propolis can be different based on the region. This finding can trigger measures to further enhance the quality of a given provenience.

Physicochemical, Functional, Molecular, and Surface properties of Bean Proteins grown in the High-Altitude Northern Himalayas

Physicochemical, Functional, Molecular, and Surface properties of Bean Proteins grown in the High-Altitude Northern Himalayas

Impact of ultrasonication on the physicochemical, structural, thermal and functional properties of Mung bean protein

Impact of ultrasonication on the physicochemical, structural, thermal and functional properties of Mung bean protein

Deacetylation enhances the structure and gelation properties of konjac glucomannan/soy protein isolate cold-set gels

This study aimed to investigate the effect of the deacetylated konjac glucomannan (DKGM), with varying degree of deacetylation (DD), on the physicochemical and structural properties of transglutaminase-induced soy protein isolate (SPI) cold-set gels. Compared with native konjac glucomannan (KGM), DKGM significantly enhanced the gel strength, water-holding capacity, and thermal stability of the composite gels, with DK3 (DKGM with 65.85 % deacetylation) showing the most significant improvement. The secondary and tertiary structures of SPI in the DK3 group were the most stable. Compared with the KGM group, the DK3 group showed a 58.32 % increase in hydrophobic interaction and a 37.98 % decrease in free sulfhydryl content. The microstructure results demonstrated that DK3 was uniformly dispersed within the SPI network, promoting the formation of a continuous and dense network structure. This was mainly due to DK3 having a moderate particle size and low viscosity. Therefore, DKGM with a moderate DD is conducive to forming a more ordered and dense gel network structure, imparting optimal gel performance to the SPI cold-set gel.

Enset starch-based biocomposite film reinforced with Ethiopian bentonite clay: Improved mechanical and barrier properties.

Improper disposal of traditional plastics leads to the generation of microplastics, resulting in severe pollution of land and oceans and posing a threat to human health and marine ecosystems. Hence, adopting eco-friendly bioplastics, particularly in food packaging, is essential. In this study, Enset starch-based biocomposite films, reinforced with Ethiopian bentonite clay at various ratios (0, 2.5, 5, 7.5 and 10 % w/w) were prepared using solvent casting method. The effect of bentonite clay on biocomposite films on structural, physicochemical, and morphological properties were analyzed. Characterization tests confirmed the even distribution of bentonite, strengthening of bonds, and enhancement of the biocomposite film properties. The biocomposite film with 5 wt% bentonite clay incorporation into enset starch exhibits optimal performance; maximum strength (increased by 132 %), less water solubility (reduction in 33 %), reduction in water vapor permeability (decreased by 42 %), and better compatibility in the morphologies attributed by the intercalated silicate layer. This study highlights the effectiveness of bentonite clay in enhancing enset starch biocomposite properties, offering a promising eco-friendly solution for biodegradable food packaging and promoting sustainable resource utilization.

Physicochemical and aromatic properties of iron-enriched tomato paste during storage

In this study, tomato paste was fortified with iron compounds at 25, 50, and 75 ppm concentrations. The effect of adding these micronutrient iron concentrations on the paste’s physical, mechanical, aromatic, and chemical properties was evaluated every 15 days over a 60-day, storage period. The results indicated a gradual decrease in pH, total soluble solids (TSS), and taste index, alongside an increase in total acidity (TA) for all treatments throughout the storage period. The highest lycopene content observed in the Fe-25 % fortified samples at 43.05 mg/kg and the lowest in the control samples at 21.57 mg/kg. Positive values for a* and b* at the beginning and throughout the storage period confirmed the dominance of red and yellow hues in the tomato paste. Viscosity gradually decreased over time. During storage, growth and changes in mold spores and acid-resistant thermophilic bacteria were limited until the 30th day, and total microorganism counts were restricted until the 45th day. The overall accuracy of the support vector machines (C-SVM) and linear discriminant analysis (LDA) method in distinguishing samples into four groups (control, fortified with 25, 50, and 75 ppm iron) were 38 % and 62 % Overall, it can be concluded that increasing the iron micronutrient enhances the nutritional value and positively affects the physical, chemical, and microbial properties and the retention of aromatic compounds in tomato paste.