Search Results (422)

Biobased composites from fast growing hemp have drawn significant attention because they are inexpensive, biodegradable, sustainable, promote the circular economy, and have good mechanical properties. This proof-of concept study focused on utilizing low value hemp hurd (H), a byproduct of hemp fiber production, as a reinforcement for use in biocomposite materials. The H was characterized by particle size, surface area and chemical composition. Mixtures of 30–50% H and 70–50% phenol-resorcinol-formaldehyde (PRF) resin were blended and subsequently extruded on a single screw extruder. The uncured (wet) blends were evaluated for their rheological properties and showed pseudoplastic behavior. The extruded biocomposites were cured and their water absorption, flexural strength/modulus, and thermal properties were determined. The water absorption properties increased with H content 17% after 12 days for 30 H to 44% for 50 H. The biocomposites containing 40% H had a flexural strength of 41 MPa, while lower values were obtained at 50% and 30% H. These results show that underutilized H can be valorized in extrudable biocomposites. Full article

Acerola is a fruit rich in vitamin C and antioxidants, but it has a short shelf life. Foam-mat dehydration is a promising method for extending the shelf life, but it can change the rheological properties of the powder. Therefore, the present study aimed to evaluate the rheology of acerola fresh pulp and the reconstituted powder, obtained by drying at 60 °C using the foam-mat method with the additive Emustab (4%), to indicate which powder concentration possesses similar rheological properties to the fresh pulp. The experiment was performed with different concentrations of reconstituted powder in deionized water (2, 4, 6, 8 and 10%, w/v). The Herschel–Bulkley model was the one that adequately adjusted to the experimental rheological data, showing that the reconstituted powder and fresh pulp are non-Newtonian fluids with pseudoplastic behavior and initial shear stress. Shear stress rose and apparent viscosity decreased with increasing shear rate, regardless of the concentration. Emustab did not modify the rheological characteristics of the acerola pulp, which maintained the non-Newtonian fluid characteristic. The 2% concentration provides a reconstituted product more like the fresh pulp. Full article

Structuring oils using oleogels (OGs) represents a promising strategy for developing semi-solid lipid matrices with applications in food and other soft systems. This study evaluated the thermal stability and physicochemical properties of an oleogel (OG) formulated with extra virgin olive oil (EVOO) and beeswax (BW, 6%). The oleogel and olive oil samples were initially characterized by thermogravimetric analysis (TGA/DTG). The beeswax and oleogel samples were initially characterized by texture analysis. An antioxidant capacity (ORAC) analysis was initially applied to the beeswax sample. An initial rheometric analysis was applied to the oleogel sample. Fatty acid profiling and infrared spectroscopy were applied initially and finally to the oleogel and olive oil samples. During the thermal processing (80 °C, 14 days) of the oleogel and olive oil, analyses of the percentage of polar compounds, refractive index, and absorption parameters (K₂₃₂ and K₂₇₀) were performed. The oleogel exhibited a soft, pseudoplastic network, with lower hardness and mechanical strength than pure beeswax. Gelation modified the thermo-oxidative stability of EVOO, showing lower levels of polar compounds (from day 7 of heating; p = 0.028) and a slight delay in the onset of thermal degradation (Tonset), suggesting partial protection against the formation of polar degradation compounds. Furthermore, the evolution of K₂₃₂ indicated differences in the formation of primary oxidation products (p = 0.027) over the 14 days of heating, while K₂₇₀ showed no differences in the formation of secondary oxidation compounds. This reflects the complex interaction between the gelled matrix and the lipid deterioration mechanisms. Overall, the results demonstrate that the incorporation of beeswax allows for a partial reduction in degradation compounds in high-temperature processes, producing technologically functional oleogels that offer a potential alternative source for structuring solid fats. This work provides relevant evidence for the rational design of oleogels based on unrefined oils and opens new opportunities for their application in food systems and gelled matrices with thermal processing requirements. Full article

Puerarin is a naturally occurring isoflavone with reported anticancer activity, yet its topical translation is constrained by limited stability and suboptimal dermal delivery. A Puerarin-loaded proniosomal gel was developed as a potential dermal delivery platform, and we performed an initial assessment of its antimelanoma activity and safety. The gel was produced by coacervation–phase separation using Span 60, Tween 80, phosphatidylcholine, and cholesterol. Physicochemical characterization included pH, entrapment efficiency, rheology, FTIR, DSC, and vesicle properties (DLS, PDI, ζ-potential). In silico geometry optimization and docking were carried out for melanoma-associated targets (MITF and DNMT3B). Biological effects were investigated in vitro on A375 melanoma cells using MTT, morphological analysis, and nuclear/mitochondrial staining, while irritation potential was evaluated in ovo by HET-CAM. The optimized formulation exhibited a skin-compatible pH and an entrapment efficiency of 62 ± 0.26%. DLS indicated a multimodal population, with a major number-weighted vesicle population in the 100–200 nm range, and a ζ-potential of −34.9 ± 0.14 mV. FTIR and DSC supported component incorporation without evidence of chemical incompatibility. The gel showed non-Newtonian, pseudoplastic, thixotropic flow, which is advantageous for topical use. Docking predicted meaningful affinities of Puerarin toward MITF and DNMT3B. The formulation reduced A375 viability in a dose-dependent manner (to 44.66% at 200 µg/mL) and, at higher concentrations, produced nuclear condensation and disruption of the mitochondrial network. HET-CAM classified the gel as non-irritant. The Puerarin-loaded proniosomal gel represents a promising topical platform with preliminary in vitro antimelanoma cytotoxic potential, warranting additional studies to validate skin delivery, efficacy, and safety. Full article

Conjugate heat transfer in non-Newtonian fluids is a fundamental phenomenon in thermal management systems. This study investigates the combined effects of magnetic field topology, heat absorption/generation, the thermal conductivity ratio, enclosure inclination, and power-law rheology using the lattice Boltzmann method. The parametric analysis shows that increasing the heat generation coefficient from −5 to +5 reduces the average Nusselt number by up to 97% for the pseudo-plastic fluids and up to 29% for the Newtonian fluids, while entropy generation increases by 44–86% depending on the thermal conductivity ratio. Increasing the inclination angle from 0° to 90° weakens convection and reduces heat transfer by nearly 77%. Magnetic field strengthening (Ha = 0–45) decreases the Nusselt number by 20–55% depending on the barrier temperature. Among all tested conditions, the highest thermal performance (maximum heat transfer and minimum entropy generation) occurs when using a pseudo-plastic fluid (n = 0.75), exhibiting high wall conductivity (TCR = 50) and heat absorption (HAPC = −5), a cold obstacle (${\mathsf{\theta }}_{\mathrm{b}}=0$), and zero inclination (λ = 0°), as well as in the absence of the magnetic field effects. These quantitative insights highlight the controllability of the conjugate heat transfer and irreversibility in the power-law fluids under coupled magnetothermal conditions. Full article

Background/Objectives: Understanding how plant-derived extracts influence the rheological and sensory behavior of emulsions is crucial for developing stable and consumer-appealing formulations. Although walnut leaf extract (Juglans regia L.) is recognized for its bioactive properties, its structural impact on cosmetic emulsions has not been systematically characterized. This study aimed to investigate the effect of increasing walnut leaf extract concentration on the rheological profile, mechanical integrity during application, and sensory performance of oil-in-water creams. Methods: Four emulsion formulations (F1–F4) containing 0%, 1%, 3%, and 5% walnut leaf extract were prepared using Olivem 1000 and Olivem 300 as emulsifiers. Rheological measurements included amplitude sweep, flow curve, frequency sweep, and thixotropy tests to assess viscoelasticity, flow behavior, and recovery. A sensory evaluation was conducted by trained panelists to correlate rheological parameters with perceived product attributes. Results: All formulations exhibited pseudoplastic, shear-thinning behavior in well-structured cosmetic emulsions during application. The addition of walnut extract significantly modified rheological responses: at 1% concentration, an increase in storage modulus (G′) and shear-thinning ratio (η₀/η∞) indicated structural reinforcement and improved spreadability, whereas higher concentrations (3–5%) led to structural softening and faster thixotropic recovery. The frequency sweep revealed a concentration-dependent shift from elastic- to viscous-dominant behavior. Sensory analysis confirmed these trends, with higher extract levels reducing stickiness and greasiness while enhancing absorption. Conclusions: Walnut leaf extract shows a concentration-dependent influence on the rheological behavior of the emulsions, strengthening the network structure at low levels while promoting softening and faster structural recovery at higher concentrations. The strong correlation between rheological and sensory parameters underscores the potential of walnut extract as a multifunctional ingredient for designing well-structured, non-greasy, and consumer-preferred cosmetic creams. Full article

To achieve the upcycling of annually upsurging lignocellulosic wastes, the artificial humification of furfural residue is investigated under hydrothermal conditions with the objective of producing a high-concentration nitrogen-phosphorus-potassium (NPK) suspension fertilizer. Through orthogonal analysis, process conditions are optimized as a liquid-to-solid (aqueous KOH to furfural residue) ratio of 15, a reaction time of 5 h and a hydrothermal temperature of 160 °C. Subsequently, we screen out a formulation of suspension agents to stabilize the alkaline leachate, in which 0.50% sodium lignosulfonate, 0.20% xanthan gum and 0.05% potassium sorbate are incorporated via wet ball-milling. The Herschel–Bulkley equation well fits the rheological characteristics of the resulting suspension fertilizer with R² value exceeding 0.99. This suspension system is thus determined as one pseudoplastic non-Newtonian fluid. Due to higher static viscosity, it demonstrates superior anti-agglomeration capacity within a temperature range of 15–55 °C, while flowing smoothly through pipes during high-speed spraying onto the soil relied on its shear thinning. These findings provide novel insights for the high-value utilization of bio-waste and the development of new fertilizers with less consumption of energy and water. Full article

Background/Objectives: Baricitinib, a selective JAK1/JAK2 inhibitor, shows therapeutic potential in psoriasis; however, its oral use is associated with systemic adverse effects, encouraging the development of topical formulations. This study aimed at evaluating the influence of petrolatum type on the stability, biopharmaceutical performance, and therapeutic activity of lipid-based formulations containing Baricitinib. Methods: Formulations were prepared with Labrafac^® Lipophile WL 1349 (L) and either liquid (LLV) or solid (LSV) petrolatum at 30% and 60% w/w. Stability, rheology, spreadability, in vitro release, ex vivo permeation, and skin retention were evaluated, along with the safety and efficacy in HET-CAM and imiquimod-induced psoriasis murine models. Results: Only 30% petrolatum formulations remained stable for 60 days. LLV exhibited Newtonian flow, higher spreadability, sustained release (83.7% at 50 h), and superior skin retention (94 µg/g of skin/cm²), whereas LSV showed pseudoplastic behavior, lower spreadability, and reduced release (47.4% at 50 h). Both formulations were non-irritant and improved stratum corneum hydration while reducing transepidermal water loss. In vivo, both reduced erythema, epidermal thickening, edema, and histological alterations, confirming anti-inflammatory efficacy. Conclusions: These results demonstrate that the vehicle occlusivity decisively modulates baricitinib’s release and activity. LLV formulation favored drug retention and enhanced permeation at 24 h. Overall, excipient selection is important in designing safe and effective topical JAK inhibitor formulations. Full article

This study investigates the emulsifying capacity (EC), emulsion stability (ES), and oleogel-forming potential of galactomannan (GM) esters modified with decanoic (GD) and palmitic (GP) fatty acids at low (L) and high (H) degrees of esterification (DE) (GDL, DE 0.37; GDH, DE 0.71; GPL, DE 0.47; GPH, DE 0.57). Oil-in-water (O/W) emulsions (6, 8, and 10% w/v) of native GM and GM esters were prepared and characterized for droplet size, ζ-potential, and rheological behavior. Esterified GMs demonstrated improved EC compared to native GM, especially at higher concentrations and lower DE. All emulsions exhibited non-Newtonian and pseudoplastic behavior, with the GDH and GPL samples showing gel-like viscoelastic profiles (G′ > G″). Emulsions were freeze-dried to form oleogels, which were then analyzed for oil-binding capacity (OBC), hardness, chemical interactions (FTIR-ATR), and microstructure (SEM). The GDH and GPL oleogels exhibited higher OBC (59–73%) and lower hardness, which can be attributed to denser polymer–oil networks and enhanced hydrophobic interactions. SEM analysis further confirmed that esterification improved the microstructural integrity of emulsion-templated oleogels. These findings support the potential of mesquite GM esters as amphiphilic oleogelators for the formulation of structured lipid systems, offering valuable applications in food and pharmaceutical industries seeking solid fat alternatives. Full article

This study evaluated the effects of different concentrations (0.25%, 0.5%, and 1.0% w/w) of highly purified (90%) β-glucan (scleroglucan—SCGL) produced by Sclerotium rolfsii on the physicochemical, rheological, microbiological, and sensory properties of full-fat yoghurt (3.2% fat). The fermentation dynamics, titratable acidity, apparent viscosity, hardness, adhesiveness, colour, microstructure, and volatile compound profiles of the studied yoghurts were analysed. The addition of SCGL increased gel hardness and viscosity, while preserving its pseudoplastic flow behaviour (n = 0.10–0.15). In samples containing 1.0% SCGL, yield stress (τ₀) increased from 0 Pa in the control to 739 Pa after 28 days of storage, pointing to the formation of a dense protein–polysaccharide network. The analysed polysaccharide slowed down lactose hydrolysis and acidification, but increased the counts of Streptococcus thermophilus (7.7 log CFU·g⁻¹) compared to the control (5.8 log CFU·g⁻¹). The volatile compound analysis showed increased acetaldehyde (5.6 mg·L⁻¹) and diacetyl (5.0 mg·L⁻¹) levels and reduced acetoin (~1.0 mg·L⁻¹) concentration, which enhanced the intensity of the buttery aroma. The sensory evaluation revealed that yoghurts containing 1% SCGL had the most desirable smooth consistency and a balanced, fresh aroma, whereas yoghurts with lower SCGL concentrations (0.25–0.5%) were characterised by a mealy mouthfeel and thinner consistency. Scleroglucan proved to be an effective natural stabiliser and flavour modulator that improved the structure, stability, and sensory quality of full-fat yoghurts. Full article

In this study, biopolymer chitosan–glucan from fruiting bodies of Agaricus bisporus (Cs-Agrif) was extracted and characterized as a sustainable alternative to commercial low molecular weight (LMW) chitosan obtained from crab shells (Cs-1). Cs-Agrif was prepared through an alkaline treatment process that included deproteination and deacetylation in the same step. The obtained sample was evaluated for its molecular weight, rheological behavior, degree of deacetylation (DD), crystallinity, and β-glucan and phenolic contents. Furthermore, the antioxidant properties of the prepared chitosan were determined under in vitro conditions using four spectrophotometric methods. Finally, its antimicrobial activity was tested against two pathogenic bacteria, one yeast, and mycotoxigenic fungi. Cs-Agrif had low molecular weight, of 45.70 ± 5.20 kDa, with pseudoplastic flow behavior. The degree of deacetylation was 92.7%. FT-IR and XRD analyses confirmed a chitosan-like structure and lower crystallinity in Cs-Agrif compared to pure commercial chitosan. The mushroom-derived chitosan contained β-glucans and phenols, indicating a chitosan–glucan complex. Antimicrobial assays showed low Cs-Agrif microbicidal concentrations (≤2.5 mg mL⁻¹) for Escherichia coli, Enterococcus faecalis, and Candida albicans. The growth of Aspergillus flavus was significantly reduced after five days of incubation. The laboratory-prepared Cs-Agrif exhibited strong antioxidant activity at 5 mg mL⁻¹, comparing to standards. Mushroom-derived chitosan–glucan biopolymer displays excellent physicochemical, antimicrobial, and antioxidant properties, confirming its potential use in biomedicine, food, and the pharmaceutical and cosmetic industries, among many others. Full article

This study examines the effects of extrusion cooking on the biofunctional, rheological, thermal, and structural properties of corn starch (CS)/whey protein isolate (WPI) blends (100/0, 50/50, 0/100 w/w, both raw and extruded) during in vitro gastrointestinal digestion. Extrusion and in vitro digestion increased antioxidant activity (2,2′-Azino-Bis (3-Ethylbenzothiazoline-6-Sulfonic Acid) Diammonium Salt and 2,2-Diphenyl-1-Picrylhydrazyl). Extrusion improved the bioaccessibility of angiotensin-converting enzyme (ACE-1) inhibitory peptides, leading to high inhibition (>90%) in the intestinal phase across all samples, with this effect consistent between raw and extruded samples during digestion. The in vitro digestion process changes the rheological behavior of the samples, from a non-Newtonian fluid (dilatant) to a Newtonian fluid. Notably, extruded CS maintained pseudoplastic behavior across all phases. Thermally, extrusion resulted in complete gelatinization of CS and denaturation of WPI, as evidenced by the absence of endotherms. Structurally, extrusion induced unfolding of WPI α-helix and β-sheet regions, leading to the formation of β-turns and random coils, which could enhance enzyme accessibility. For CS, a decrease in the degree of double helix and order was observed, indicating an alteration of its ordered molecular structure. Additionally, the extrusion process slightly increased the amount of resistant starch. This work shows that extrusion generates antioxidant compounds by bioactive peptide release. Full article

The growing demand for sustainable materials in construction and sanitation has increased interest in natural fibre-reinforced polymer composites. Rice husk, an abundant agricultural by-product, offers a promising alternative as a reinforcing filler in polypropylene (PP) composites. This study aims to assess the suitability of PP composites reinforced with micronised rice husk particles for application in sanitary components. Two formulations containing 20% and 30% rice husk were developed and characterised. Comprehensive analysis included morphological, thermal, rheological, mechanical, hygroscopic, and tribological testing. Results showed that particles incorporation enhanced thermal stability and crystallinity due to a nucleating effect, with the 30% composite showing higher crystallinity. Thermogravimetric analysis showed that although the T₅% decreased from 374.1 °C for neat PP to 309.2 °C and 296.2 °C for the 20% and 30% composites, respectively, the DTG peak temperatures increased by 15.9 °C and 17.6 °C, indicating a delayed main decomposition stage of PP matrix and enhanced overall thermal stability. Rheological behaviour revealed increased viscosity and pseudoplasticity at higher particle content Mechanical characterisation showed an increase in Young’s modulus from 1021 MPa for neat PP to 1065 MPa (+4%) and 1125 MPa (+10%) for PP_Rice_20% and PP_Rice_30%, respectively. In contrast, the nominal strain at break dropped sharply from 238% (PP) to 30% (PP_Rice_20%) and 16% (PP_Rice_30%). Shrinkage decreased from 1.31% (PP) to approximately 1.05% in both composites, indicating improved dimensional stability. However, water absorption rose from 0.015% (PP) to 0.111% (PP_Rice_20%) and 0.144% (PP_Rice_30%), accompanied by an increase in surface roughness (Sa from 0.34 µm to 0.78 µm and 1.06 µm, respectively). The composite with 20% rice husk demonstrated better filler dispersion, reduced water uptake, and smoother surfaces, making it more suitable for injection-moulded components intended for use in humid environments. Overall, the study supports the use of agricultural residues in high-performance biocomposites, contributing to circular economy strategies and the development of more sustainable polymer-based materials for technical applications. Full article

Surgical site infections in oral and maxillofacial interventions are often exacerbated by biofilm formation, and current antimicrobial treatments are hampered by issues such as resistance and adverse effects. This article aimed to develop, characterize, and evaluate the antimicrobial activity of Lippia sidoides Cham. essential oil (LSEO) gel composed of poloxamer (P) and chitosan (C). Gas chromatography–mass spectrometry (GC-MS) analysis identified thymol as the major component of LSEO (71.04%). In situ P-gels containing LSEO (0.25–1.0%) were produced with and without C. The addition of C resulted in gels with nanometric particle sizes (263.8 ± 231 nm; PDI 0.39 ± 0.17) and a positive zeta potential (+4.81 ± 1.97 a + 8.19 ± 0.51 mV), exhibiting pseudoplastic behavior in rheological analysis. The sol–gel transition temperature (Tsol–gel) was found to be between 20 and 28 °C, with a transition time at 37 °C ranging from 18.76 ± 1.24 s to 46.46 ± 8.89 s. LSEO showed MIC values of 256, 128, and 128 µg/mL against Staphylococcus aureus, Escherichia coli, and Candida albicans, respectively, while in situ LSEO gels presented MIC values above 5 µg/mL for all tested strains. Therefore, the developed gel containing LSEO showed promising application in dentistry, offering a potential new treatment perspective for surgical site infections in oral and maxillofacial surgery. Full article

The effect of the high-pressure homogenization (HPH) process (one-stage; applied pressure of 10 MPa and 20 MPa) and furcellaran addition (0.25% and 0.50%, w/w) on the physicochemical and rheological properties of chocolate milk drinks was evaluated. Non-homogenized samples and the milk sample used to produce all model chocolate milk drink samples were also evaluated for comparison. The addition of furcellaran and the HPH process significantly influenced the monitored characteristics of the model samples. In particular, the addition of furcellaran caused an increase in shear stress and viscosity, and HPH also had a noticeable effect on these rheological properties. From the results obtained, it can be concluded that the model samples of chocolate milk drinks exhibited a pseudoplastic behavior. Furthermore, the results of the physicochemical analyses showed a slight increase in dry matter and total soluble solids contents due to furcellaran addition. The solid particle sedimentation values of the tested samples decreased due to furcellaran addition (up to 11.99%.). In addition to the effect on rheological properties, the HPH regime slightly increased the sample’s pH values (6.80–6.81). The application of HPH and furcellaran addition may appear advantageous in manufacturing chocolate milk drinks (or dairy-based suspensions) with enhanced physical, flow and sensory properties. Full article