Search Results (273)

Oleogel-based fat systems were developed using citrus fiber (CF) and cold-pressed pumpkin seed oil by-product (PSB) through an emulsion-template approach and evaluated as palm oil substitutes in a model chocolate sauce system. Oleogels were prepared by varying CF (4–5%) and PSB (0–2%) concentrations and characterized in terms of rheological, textural, and sensory properties and oxidative stability. The emulsions exhibited predominant elastic behavior (G′ > G″), with storage modulus (K′) values increasing from 694.12 to 2242.54 Pasⁿ as CF and PSB concentrations increased. Chocolate sauces formulated with CF–PSB oleogels showed pseudoplastic flow behavior and solid-like viscoelastic characteristics, with K′ values ranging from 89.32 to 356.56 Pasⁿ, compared to 34.84 and 16.95 Pasⁿ for the palm oil (C1) and sunflower oil (C2) controls, respectively. Temperature sweep and thermal loop tests demonstrated improved thermal resistance and emulsion stability in oleogel-containing chocolate sauces. Oleogel-based chocolate sauces also showed superior emulsion stability under thermal cycling and greater oxidative stability compared to the C2 sample. Texture profile analysis revealed increased hardness and spreadability with higher CF and PSB contents, consistent with rheological findings. Oleogel-based chocolate sauces also demonstrated enhanced oxidative stability, with induction period values reaching 18:55 h compared to 5:13 h for the sunflower oil control and approaching the palm oil control (20:13 h). Texture profile analysis revealed increased hardness and spreadability with higher CF and PSB contents. Sensory evaluation indicated that sauces containing 5% CF and 1–2% PSB received the highest scores for flavor, consistency, and overall acceptability. Full article

Background: Iodine-based antimicrobial systems remain highly attractive due to their broad-spectrum activity; however, the clinical application of free iodine is limited by its instability and cytotoxicity. This study aimed to develop polyethylene glycol (PEG)-based hydrophilic ointment formulations containing a dextrin/polyvinyl alcohol/iodine complex (D/PVA/I) and to evaluate their physicochemical properties, antimicrobial activity, and cytotoxicity. Methods: Hydrophilic ointment formulations containing 2.5%, 5.0%, and 10.0% D/PVA/I were prepared using a PEG-based matrix composed of PEG 4000, PEG 400, and glycerol. Physicochemical characterization included organoleptic evaluation, pH measurement, rheological analysis, and UV–visible (Ultraviolet–visible) spectroscopy. Antimicrobial activity was assessed using agar diffusion and minimum bactericidal concentration (MBC) assays against Staphylococcus aureus, Escherichia coli, Enterococcus hirae, and Pseudomonas aeruginosa. Cytotoxicity was evaluated in Madin–Darby Canine Kidney (MDCK) cells using the MTT assay. Results: All formulations exhibited homogeneous semisolid structure and physiologically acceptable pH values (4.94–5.45). Rheological analysis demonstrated non-Newtonian pseudoplastic (shear-thinning) behavior. The flow behavior index (n) ranged from 0.03 to 0.33 according to the Ostwald–de Waele model, confirming shear-thinning characteristics, while viscosity increased with increasing D/PVA/I concentration. UV–visible spectroscopy confirmed the presence of triiodide ions (I_3⁻), characterized by absorption maxima at approximately 287 and 350 nm, indicating preservation of active iodine species within the PEG matrix, while placebo (blank) formulation analysis confirmed the absence of corresponding absorption bands, demonstrating that the PEG-based matrix does not contribute to the characteristic spectral features. The formulations demonstrated broad-spectrum antimicrobial activity, with MBC values ranging from 0.01 to 0.02 µg/mL. Cytotoxicity studies revealed moderate toxicity of the D/PVA/I complex (CC₅₀ = 0.82%) (50% cytotoxic concentration (CC₅₀) and significantly lower toxicity of the PEG-based ointment base (CC₅₀ = 18.38%). Conclusions: The developed PEG-based hydrophilic ointment formulations containing the D/PVA/I complex demonstrated favorable physicochemical characteristics, stability of iodine species, pronounced antimicrobial activity, and acceptable cytotoxicity profiles. These findings highlight the potential for the developed systems to be promising topical antimicrobial formulations. Full article

This study comprehensively assesses the effect of ultrasonic treatment on the physicochemical, nutritional, and rheological properties of mung bean (Vigna radiata) milk. Ultrasonic treatment (24 kHz, 200–300 W, 5–20 min at 25 ± 2 °C) was applied after preliminary aqueous extraction (60–70 °C, 15–20 min) and compared with conventional aqueous extraction (control). Ultrasound significantly increased protein extractability (from 0.11% to 0.15%, p = 0.008) and improved the amino acid profile (8–18% increase without signs of degradation). The content of potassium, phosphorus, and magnesium increased by 6–12% (p < 0.001 for K and P, p = 0.001 for Mg), indicating more efficient release of intracellular components. B-group vitamins remained stable, while fat-soluble vitamins (A, E) were not detected. Total mesophilic microflora was reduced to 1.2 × 10⁴ CFU/mL (p = 0.021), with no pathogenic microflora detected. Rheological measurements confirmed pseudoplastic behavior (n < 1), an increase in viscosity up to 20.0 cP, and the formation of a more homogeneous dispersion. Thus, ultrasonic treatment performed under controlled non-thermal conditions after preliminary aqueous extraction effectively improves the structural, functional, and nutritional quality of mung bean plant-based milk. Full article

Background/Objectives: Plant-derived soluble fibers are being explored as sustainable prebiotic ingredients; however, tropical legumes such as Leucaena leucocephala remain understudied. This study evaluated soluble fibers from L. leucocephala seeds after simulated gastrointestinal digestion, focusing on rheological properties, microbial selectivity, metabolite production, and intestinal safety. Methods: The anatomical parts of the seed underwent INFOGEST 2.0 digestion. Soluble fibers were characterized by GC-MS monosaccharide profiling, viscosity, and SEM/EDS analyses, and were used as substrates for both probiotic and pathogenic bacteria. Fermentation supernatants were analyzed for short-chain fatty acids and lactate, and cytotoxicity was assessed using Caco-2 cells. Results: Endosperm polysaccharides exhibited high apparent viscosity (>300 cP) and pseudoplastic behavior. Monosaccharide profiles revealed the presence of galacto-oligosaccharides and arabinoxylo-oligosaccharides in the oligosaccharide fraction, and galactomannans, xylans, and arabinoxylans in the polysaccharide fraction. Polysaccharides selectively promoted the growth of Lacticaseibacillus rhamnosus GG and Bifidobacterium spp., comparable to or exceeding that of fructo-oligosaccharides (p < 0.05), while limiting pathogenic bacteria. Fermentation produced acetate and lactate concentrations of >4500 ppm and >1000 ppm, respectively. Caco-2 viability remained >90% across all treatments. Conclusions: Compartment-resolved analysis identified the endosperm as the principal source of digestion-resistant viscous fiber, selectively fermented by probiotic bacteria at levels matching or exceeding fructo-oligosaccharides. These findings position L. leucocephala endosperm fiber as a candidate prebiotic substrate, warranting further preclinical evaluation. Full article

(1) The growing interest in the use of natural and sustainable ingredients highlights the investigation of vegetable oils in dermato-cosmetic applications. In this context, the vegetable oil obtained from walnut (Juglans regia L.) is of actual interest due to its composition rich in unsaturated fatty acids. The aim of the present study was to investigate and characterize walnut oil from a physicochemical, structural, and rheological point of view. (2) The oil was obtained by a cold pressing process from walnut seeds, with a yield of about 51.03 ± 1.41%, and subsequently analyzed by complementary methods. (3) The results show an acceptable physicochemical profile, characterized by appropriate values of density, pH, and spreadability. The oxidative stability indicated a moderate resistance to degradation, specific to oils rich in polyunsaturated fatty acids. Fourier infrared transform spectrometry (FTIR) analysis confirmed the presence of functional groups characteristic of triglycerides, without indications of advanced oxidation, and atomic force microscopy (AFM) investigations revealed a heterogeneous morphology. The rheological properties indicated a pseudoplastic behavior, favorable for topical application. The determination of heavy metals confirmed the safety of the raw material for the intended dermato-cosmetic use. While arsenic levels were slightly above the strict Codex Alimentarius limits for foodstuffs, all values remained within the safety ranges established for cosmetic ingredients. A total of six fatty acids were found in cold-pressed walnut oil, determined using GC-MS methods. The number of compounds identified in the silylated sample was found to be 17. The antioxidant activity determined using DPPH and ABTS methods was generally considered good and relatively stable over time. The measured sun protection value (SPF) demonstrates a favorable capacity to act as a photoprotective ingredient against ultraviolet (UV) radiation. (4) Overall, the results demonstrate that walnut oil presents adequate physicochemical and structural properties, supporting its further use as a potential cosmetic raw material. Full article

The aim of this study was to develop and characterize a soft gel dosage form based on an ethanol extract and essential oil from the rhizomes of Iris scariosa L., and to evaluate its antioxidant and anti-inflammatory activity. Plant material was extracted using ultrasonic extraction with ethanol of varying concentrations. Phytochemical composition was analyzed by HPLC and GC-MS. Carbomer-based gels were formulated and assessed for physicochemical properties, rheological behavior, stability, and release of active compounds. The highest extraction yield (21.16%) was achieved with 70% ethanol. The extract contained phenolic compounds, mainly epicatechin and gallic acid, as well as flavonoids such as naringin and phlorizin. The essential oil was rich in medium-chain fatty acids. The developed gels were transparent, homogeneous, and exhibited stable pH values within the physiological skin range, along with pseudoplastic flow behavior. Significant antioxidant activity was observed in both the extract and gel in reactive oxygen species and lipid peroxidation models. In a formalin-induced inflammation model, the gel significantly reduced paw edema. These findings demonstrate the potential of the Iris scariosa-based gel as a promising phytopharmaceutical formulation for topical application. Full article

Garlic (Allium sativum) has antimicrobial and antioxidant properties. However, only the cloves are used from the bulb; the peels or husks are waste material with limited utility that nevertheless retain properties that can be exploited in other materials such as edible films or coatings. Chitosan is a widely used biopolymer, due its interesting properties. The same is true for alginate and pectin, which are polysaccharides that have interesting application areas; among the most common are film or coating materials in the food industry. Therefore, in this research, comprising the elaboration of films based on Chitosan-Pectin-Alginate (Q-P-A) reinforced with garlic husk (GH) particles, the films were characterized by Brookfield viscosity (the biopolymers solutions), Fourier Transform infrared Spectroscopy (FTIR), Dynamic mechanical analysis (DMA), and thermogravimetry (TGA). According to the results, the addition of GH caused a significant decrease in viscosity without altering the pseudoplasticity behavior and also generating physical interactions with the matrices; no chemical reaction byproducts were identified by FTIR. An increase in the reinforcing effect was identified in Q-GH films, whereas the opposite effect was observed in Q-P-A-GH films. In addition, no significant changes in the thermal stability were observed. Full article

High-value metabolites, such as antibiotics and enzymes, are primarily produced using filamentous fungi. However, their morphological complexity increases broth viscosity during biomass growth, hindering industrial scale-up by impairing both power input and mass transfer. The interaction between biomass growth, rheology, power input, and oxygen transfer is first addressed here by evaluating mycelial rheology and determining the volumetric mass transfer coefficient (k_La) (dynamic method) and oxygen uptake rate (respirometry) across different operating conditions. These confirmed that the mycelial broth’s pseudoplastic behavior significantly influences volumetric power input and k_La correlations. However, specific power input analysis revealed that operating at higher stirring rates (800 rpm) at higher cell-density cultures is 28.17% more energetically efficient than at low speeds (500 rpm). Furthermore, the oxygen supply-to-demand ratio, calculated via Excel model-fitting, allowed for the estimation of “metabolic power input” which represents the required energy to fit oxygen demand. Results also reveal that at 3.67 ± 0.34 g L⁻¹ of biomass effectively channel up to 51% of total energy toward aerobic metabolism, compared to only 17–30% for 0.73 ± 0.01 g L⁻¹ of biomass. These findings show that volumetric power inputs around 4 kW m⁻³ improve oxygen transfer efficiency, even at relatively high biomass concentrations. Full article

The effect of microstructural evolution on mechanical behavior of carbon/carbon composites after heat treatment has been investigated. Two kinds of samples, heat-treated at 2300 °C and 2700 °C, were used in the current study. As the heat treatment temperature is 2700 °C, the pyrolytic carbon acquires a higher orientation via carbon atomic layer rearrangement, accompanied by microstructural evolution such as self-healing of concentric ring cracks, narrowing of the fiber/matrix interface and bridging between adjacent fibers. This microstructural evolution results in a significant decline in the mechanical properties of the composites: compressive strength, flexural strength, and shear strength decreased by approximately 60%, 68%, and 71%, respectively, while the corresponding fracture strains increased by 52%, 25%, and 19%, respectively, indicating an improvement in pseudoplasticity. Full article

Olive mill wastewater (OMW) is an agro-industrial byproduct rich in polyphenols and other bioactive compounds with documented antioxidant and antimicrobial properties. In this study, purified OMW fractions (RO1 and MD2), previously characterized by high polyphenol content and strong antioxidant activity, were incorporated (10% w/w) into cellulose-based hydrogels intended for topical application. Hydrogels were prepared using carboxymethyl cellulose (CMC), hydroxyethyl cellulose (HEC), hydroxypropyl methylcellulose (HPMC), and methylcellulose (MC) at concentrations of 1.5–2.0% (w/w). The formulations were characterized in terms of organoleptic properties, pH, rheological behavior, swelling capacity, weight loss, antioxidant activity (DPPH assay), and microbiological activity against selected skin pathogens, including antibiotic-resistant strains. Rheological analysis confirmed pseudoplastic behavior suitable for topical administration. OMW-loaded hydrogels exhibited significant radical scavenging activity compared to blank formulations and demonstrated antimicrobial efficacy, supporting the preservation of OMW bioactivity within the polymeric network. The results highlight the potential of cellulose-based hydrogels as sustainable and biocompatible carriers for the valorization of OMW in dermatological applications, particularly for the management of oxidative stress and bacterial skin infections. Full article

The incorporation of plant-derived oils into cosmetic formulations has attracted increasing interest due to their natural origin, skin compatibility, and multifunctional formulation roles. Argan and castor oils are widely used in cosmetic products as emollient lipid components with intrinsic antioxidant properties. However, limited studies have systematically evaluated the physicochemical stability and antioxidant performance of emulsions combining these two oils. The aim of this study was to develop and comprehensively characterize a stable oil-in-water (O/W) cosmetic emulsion based on argan and castor oils using a natural non-ionic emulsifier (C14–22 Alcohol (and) C12–20 Alkyl Glucoside). Particular emphasis was placed on formulation stability, as it represents a critical prerequisite for further product evaluation. Stability was investigated through thermal stress testing (4–37 °C), centrifugation assays, droplet size analysis, and zeta potential measurements. Complementary physicochemical and structural characterization was performed using rheological analysis and Fourier transform infrared (FT-IR) spectroscopy. The formulated emulsion exhibited good physical stability with no phase separation under the tested conditions, a skin-compatible pH, a uniform droplet size distribution (4.15 ± 0.68 µm), and pseudoplastic, moderately thixotropic rheological behavior. Antioxidant capacity was assessed using the 2,2-diphenyl-1-picrylhydrazyl (DPPH) radical scavenging assay, yielding an IC₅₀ value of 19.21 ± 1.02 mg/mL. Overall, this study provides a formulation-oriented framework for the development and evaluation of stable natural oil-based O/W emulsions intended for cosmetic applications, supporting future optimization and biological validation. Full article

The rising demand for sustainable and functional ingredients necessitates the development of novel replacers for traditional food components, such as eggs, which are critical for structure and aeration in baked goods. This study investigated hydrocolloids derived from cassava (Manihot esculenta) as a partial egg substitute in sponge cakes, evaluating their effect on rheological, physicochemical, nutritional, and sensory properties. The resulting cake batter exhibited characteristic non-Newtonian, pseudoplastic, and viscoelastic fluid behavior. A microstructural analysis confirmed that the stabilized, higher-viscosity doughs successfully facilitated the formation of larger, more stable air bubbles, effectively mimicking the structural role of the egg. Physicochemical assessments demonstrated a high product equivalence; the fat content showed no significant difference (p < 0.05) compared to the control, while pH and carbohydrate levels decreased. Crucially, the optimized formula, CK-S50-H2.5 (50% egg and 2.5% hydrocolloids substitutions), exhibited a minimal color difference (ΔE) consistent with the control, preserving product appearance. Sensory evaluation confirmed that hydrocolloid substitution did not compromise consumer acceptance. Panelists preferred cakes utilizing lower egg substitution levels for their enhanced flavor and texture. These findings establish that cassava hydrocolloids serve as an effective and functional partial egg replacer, yielding a high-quality and well-accepted product and offering a valuable, sustainable solution for the food industry. Full article

This work presents a method to encapsulate plant extracts within a binary polysaccharide carrier and to characterize the physicochemical and rheological performance of the resulting biocomposites in the context of food use. Using a starch/psyllium matrix, extracts from Sambucus nigra (SN), Aronia melanocarpa (AM), and Echinacea purpurea (EP) were effectively protected and incorporated through a stepwise workflow encompassing matrix preparation, encapsulation, structural verification, and functional assessment. SEM revealed a porous network containing uniformly distributed, extract-loaded spherical structures (~800–1500 nm), while FTIR supported the presence of hydrogen bonding and hydrophobic interactions that contributed to system stability. The prepared nanoemulsions showed shear-thinning (pseudoplastic) behavior, indicating favorable processing characteristics, whereas most physicochemical and bioactivity measurements were performed on lyophilized composites. The dried materials preserved extract-specific color signatures (ΔE > 5) and exhibited distinct thermal responses: AM produced a pronounced plasticizing effect (Tg reduced by >20 °C), while the incorporation of extracts generally delayed thermal degradation, consistent with polyphenol–starch interactions. Phase-transition behavior was also altered, with melting peaks suppressed for SN and AM and melting temperatures lowered for EP. Surface analysis indicated increased hydrophobicity and a reduced polar component of surface free energy, suggesting improved moisture barrier potential. Antioxidant capacity closely tracked total phenolic content (r > 0.94), with caffeic acid contributing strongly, particularly in EP-based systems. Antimicrobial activity depended on extract type (broad-spectrum for EP, selective for SN, minimal for AM), and the comparatively higher sensitivity of Gram-negative bacteria points to improved phenolic availability and membrane interactions upon encapsulation. Collectively, these results highlight the starch/psyllium matrix as a flexible platform for stabilizing plant extracts while enabling tunable functional attributes for functional food applications. Full article

In this work, we report the synthesis and evaluation of a bioink based on marine collagen, chitosan, and silica-doped hydroxyapatite (HA–SiO₂) for extrusion-based 3D bioprinting. FTIR spectroscopy confirmed amide (I–III) and phosphate/siloxane signals, TGA showed initial dehydration and degradation stages compatible with the process’s thermal handling, and SEM revealed an interconnected porous microstructure. Rheologically, the ink exhibited elastic dominance (G′ > G″) within the linear range and pseudoplastic, shear-thinning behavior—consistent with pneumatic extrusion. Process evaluation on a BIO X printer (14 G nozzle, low print speeds, moderate pressure, cartridge at 37 °C to 45 °C, and a cooled build platform) enabled deposition of strands with local shape retention. However, filament continuity was limited and line width varied, indicating only preliminary printability and a narrow operating window. Overall, physicochemical, microstructural, and rheological evidence supports the formulation’s viability as a starting point for scaffold fabrication. Full article

Injection molding has been used for many years in the fabrication of thermoplastic parts with different complexities. With metal and ceramic injection molding, it is possible to realize at the end of the related process chain sintered metal and ceramic parts. Parts made from glass are rather seldom realized applying powder technology methods. This work describes the production of devices made from a commercial soda-lime glass applying the process chain of powder injection molding, covering the individual process steps like compounding, shaping, debinding, and sintering. In the first step, a binder consisting of polyethylene glycol (PEG) with different average molecular masses (4000, 8000, and 20,000 g/mol), polyvinyl butyral (PVB), and stearic acid (SA) were used for compounding new feedstocks with a solid load of 55 Vol% and 60 Vol%. As filler, a soda-lime glass with an average particle size of 6.1 µm, an almost symmetrical particle size distribution, a specific surface area of 0.78 m²/g, and a spherical morphology was applied. The measured equilibrium torque during compounding was low, with values between 2.5 and 5.5 Nm depending on the solid load and average molecular mass of the investigated PEG. All feedstock possessed a pseudoplastic flow behavior in the shear rate range between 10 and 3500 1/s. Small disk-shaped parts, as well as large cuboids and plates, were injection molded to a good quality. These green bodies were pre-debinded in water to remove the PEG, subsequently followed by thermal debinding to eliminate the remaining organic moieties. The concluding sintering in the temperature range between 660 and 680 °C delivered glass parts with huge density values close to 100% of the theoretical value, as measured by the Archimedes method. The principal feasibility of glass injection molding with a suitable feedstock system could be demonstrated successfully. Full article