Search Results (63)

Curcumin is a polyphenolic compound isolated from Curcuma longa, which is widely recognized for its therapeutic properties: particularly its strong anti-inflammatory and antioxidant activities. However, its practical incorporation into functional foods, especially aqueous dairy beverages, is severely hindered by its extremely low water solubility, poor chemical stability (notably at the near-neutral pH of milk), and very limited oral bioavailability. This review provides a critical synthesis of the literature published in the last two decades, with a focus on the development and application of food-grade oil-in-water (O/W) nanoemulsions to advanced colloidal delivery systems. It covers the fundamental principles of nanoemulsion formulation, including the selection of the oil phase, surfactants, and stabilizers, as well as both high-energy and low-energy fabrication techniques. It further examines the integration of these nano-delivery systems into dairy matrices (milk, yogurt, cheese), highlighting key interactions between nanoemulsion droplets and native dairy constituents such as casein micelles and whey proteins. Critically, findings indicate that nanoencapsulation not only enhances curcumin’s solubility but also protects it from chemical degradation during industrial processes, including pasteurization and sterilization. Moreover, the dairy matrix structure plays a key role in modulating curcumin bioaccessibility, with fortified products frequently exhibiting enhanced stability, shelf life, and sensory attributes. Finally, key technological challenges addressed the heterogeneous global regulatory landscape surrounding biopolymers and future trends: most notably, the growing shift toward “clean-label” biopolymer-based delivery systems. Full article

Nanoemulsions (NEs) offer a promising strategy for delivering lipophilic cannabidiol (CBD) to protect skin from particulate matter (PM)-induced damage. In this study, CBD-loaded oil-in-water NEs based on Brij^® O10 (polyoxyethylene (10) oleyl ether) and olive oil were prepared by the phase inversion temperature (PIT) method and characterized. A 20% w/w Brij^® O10 formulation (B20) remained clear and stable for 30 days. CBD solubility was markedly enhanced in Brij^® O10 micelles and further increased in NEs, exceeding theoretical predictions and indicating synergistic solubilization in the oil–surfactant system. CBD incorporation lowered the PIT and induced nonlinear changes in droplet size with oil content. All formulations exhibited nanoscale droplets by dynamic light scattering and transmission electron microscopy, moderately low zeta potentials consistent with nonionic steric stabilization, and maintained physical stability despite increased turbidity at higher oil levels. In a full-thickness human ex vivo skin model exposed to PM, both blank and CBD-loaded NEs reduced interleukin-6 (IL-6) and matrix metalloproteinase-1 (MMP-1) in PM-exposed skin, with CBD-loaded NEs providing additional reductions and uniquely restoring procollagen type I C-peptide (PIP) relative to their blanks. Overall, PIT-based CBD NEs enhance CBD solubilization and protect human ex vivo skin from PM-induced inflammation and extracellular matrix degradation. Full article

Membrane separation is a promising technology for emulsified wastewater treatment. However, conventional membrane often suffer from limitations such as low mechanical strength, the inherent “trade-off” effect between flux and separation efficiency, and poor antifouling properties. To address these challenges, we report a novel composite membrane (CFM-UiO-66-(COOH)₂) fabricated by in situ growth of functionalized UiO-66-(COOH)₂ on a mechanically robust collagen fiber membrane (CFM) substrate. The resulting composite leverages the inherent properties of the CFM, along with the controlled generation of charge-neutralization demulsification sites and size-sieving filtration layers from the UiO-66-(COOH)₂. This CFM-UiO-66-(COOH)₂ exhibited superwetting behavior and achieved efficient separation of cationic surfactant-stabilized oil-in-water micro- and nano-emulsions. Specifically, the CFM-UiO-66-(COOH)₂ achieved separation efficiencies exceeding 99.85% for various cationic O/W emulsions, with permeation fluxes ranging from 178.9 to 225.9 L·m⁻²·h⁻¹. The membrane also demonstrated robust antifouling properties, excellent acid/alkali resistance, high abrasion durability, and good biocompatibility. Importantly, stable performance was maintained over six consecutive separation cycles. These characteristics, combined with the electrostatic interactions between carboxyl groups on the UiO-66-(COOH)₂ and cationic contaminants, suggest that CFM-UiO-66-(COOH)₂ holds significant potential for practical and sustainable wastewater treatment applications. Full article

This study investigated the relationships between emulsion droplet triacylglycerol (TAG) crystallinity and colloidal acid stability on in vitro digestion microstructure, lipolysis, and docosahexaenoic acid (DHA) bioaccessibility. Oil-in-water (o/w) nanoemulsions (20 wt%) composed of 50/50 DHA-rich algal oil with either palm stearin (PS) or olein (PO), and either acid-stable Tween 80 (2.0 wt%; AS) or acid-unstable soy lecithin (2.2 wt%; AU) were fast or slow cooled to 37 °C after microfluidization. Similar particle size distributions and D_3,2 (~131–142 nm) and D_4,3 (~208–239 nm) values were achieved. All emulsions were highly electronegative (~−45–70 mV) and differences (p < 0.05) were due to emulsifier type, as expected, and cooling rate. Next, emulsions were subjected to INFOGEST in vitro digestion for analysis of intestinal lipolysis by free fatty acid titration and DHA bioaccessibility. As expected, AU emulsions flocculated, forming larger aggregates during the gastric phase. Slower lipolysis was observed for the AU emulsions (p < 0.05), attributed to gastric phase aggregation, and lower 2 h lipolysis was observed for the PS emulsions (~74–77%) based on the presence of crystallinity. DHA bioaccessibility was high (~57–88%), especially for the AS emulsions (p < 0.05). Therefore, emulsion colloidal acid stability and TAG physical state significantly impacted emulsion gastric microstructure, digestion, and bioaccessibility. Full article

Background/Objectives: The study of biological activity of plants and their metabolites is an important approach for the discovery of new active material. However, little is known of the properties of the Microlicia genus. In addition to natural products, nanotechnology demonstrates considerable potential in pharmacotherapy. The utilization of nanoemulsions holds considerable promise in enhancing the efficacy of drugs, reducing dose, and therefore, lowering of toxic effects. Methods: In this context, antimicrobial and trypanocidal activities were evaluated to the free and encapsulated essential oil from M. graveolens in oil-in-water (o/w) nanoemulsion. Results: This oil is composed mainly of cis-pinocarvyl acetate (~80.0%). The nanoemulsions were prepared by phase inversion method and showed mean particle size of 58 nm, polydispercity index of 0.09, pH 7.8, zeta potential of −21.9 mV, electrical conductivity of 0.38 mS/cm, and good stability. The essential oil was active against all five Gram-positive bacteria tested, and the formulation enhanced this ability. The cytotoxicity effect on L929 cells was also reduced after encapsulation of this oil in o/w nanoemulsion. In addition, the oil and the nanoemulsion were able to inhibit the growth of Trypanosoma cruzi. Conclusions: Thus, the development of a nanoemulsion loaded with M. graveolens essential oil is an easy and low-cost way to obtain and deliver the cis-pinocarvyl acetate compound as well as allow its use in the treatment of diseases caused mainly by the genus Listeria and Staphylococcus. Full article

External environmental stressors and internal physiological changes frequently compromise the skin barrier, resulting in conditions such as dermatitis and dehydration. A key underlying factor is the depletion of ceramides, essential lipids in the stratum corneum that maintain skin integrity. Although topical ceramide supplementation is effective for barrier repair, its clinical application is limited by poor solubility and low skin permeability. To overcome these challenges, this study developed an oil-in-water nanoemulsion (O/W-NE) using ultrasonic emulsification for the efficient transdermal delivery of ceramide C2. Octyldodecanol was selected as the oil phase to enhance ceramide solubility, while glycerin was incorporated to increase aqueous phase viscosity, reduce particle size, and function as a biocompatible penetration enhancer. The optimized nanoemulsion achieved a particle size of 112.5 nm and an encapsulation efficiency of 85%. Its performance was evaluated via in vitro release, ex vivo skin permeation, and in vivo biocompatibility studies. Mechanistic investigations revealed that both particle size and glycerin concentration significantly influenced ceramide penetration into the epidermis and dermis. Additionally, the nanoemulsion exhibited moisturizing and barrier-repair effects in a damaged skin model. Overall, this O/W-NE offers a stable, non-invasive strategy for enhancing ceramide delivery and restoring skin barrier function. Full article

Background: Despite the rapid development of nanoemulsions in recent years, no method has been established for the preparation of milbemycin oxime nanoemulsions. Milbemycin oxime is a widely used macrolide antibiotic in veterinary medicine, particularly for treating parasitic infections in animals such as dogs. However, its poor solubility in water limits its bioavailability and therapeutic efficacy. Developing a nanoemulsion formulation can enhance its solubility, stability, and bioavailability, offering a more effective treatment option. Methods: In this experiment, oil-in-water (O/W) milbemycin oxime nanoemulsions were successfully prepared by the phase inversion composition (PIC) method using ethyl butyrate as the oil phase, Tween-80 as the surfactant, and anhydrous ethanol as the co-surfactant. The region of O/W nanoemulsions was identified by constructing a pseudo-ternary phase diagram and, based on this, was screened by determining the droplet size, polydispersity coefficient, and zeta potential of each preparation. Results and Conclusions: The finalized formulation had a 2:1 ratio of surfactant to co-surfactant and a 7:3 ratio of mixed surfactant to oil, and its droplet size, polydispersity index (PDI), and zeta potential were 12.140 ± 0.128 nm, 0.155 ± 0.015, and −4.947 ± 0.768 mV, respectively. Transmission electron microscopy confirmed the spherical uniform distribution of droplets, and the nanoemulsions passed thermodynamic stability tests. The in vitro release of milbemycin oxime nanoemulsions followed first-order kinetic equations. In conclusion, nanoemulsions are an interesting option for the delivery of poorly water-soluble molecules such as milbemycin oxime. Full article

Background: Skeletal muscle, as the largest organ in the body and the main protein pool, is crucial for various physiological processes, but atrophy of skeletal muscle can result from glucocorticoids, including dexamethasone, or from aging. Astaxanthin (AST) is a ketocarotenoid with a variety of physiological activities. However, the clinical application of AST is hampered by its strong hydrophobicity, intense off-flavors, and susceptibility to oxidation. Methods: In this study, we prepared whey protein isolate (WPI)-encapsulated AST nanoemulsion (WPI-AST, W-A) and investigated its alleviating effects on dexamethasone-induced skeletal muscle atrophy. Results: The optimal concentration of astaxanthin was determined to be 30 mg/mL with an oil/water ratio of 1:5. The W-A was a typical oil-in-water (O/W) emulsion with a particle size of about 110 nm. The bioaccessibility of astaxanthin was significantly improved, with the off-flavors of astaxanthin effectively masked. After oral administration, the W-A further ameliorated skeletal muscle atrophy by inhibiting skeletal muscle catabolism, promoting skeletal muscle production, and inhibiting mitochondrial autophagy compared with the same dose of WPI and AST. In addition to this, the W-A further improved the glycometabolism of skeletal muscle by reducing the expression of Foxo3 and increasing the expression of PGC-1α. Conclusions: In conclusion, the W-A nanoemulsion demonstrated good therapeutic value in alleviating skeletal muscle atrophy. Full article

Canola oil, extracted from Brassica napus, is appreciated for its nutritional profile, but its use in the food industry is limited by its susceptibility to oxidation. This study aimed to evaluate the nanoemulsion of canola oil by sonication to develop stable nanoemulsified gels from protein and starch systems. Two stages were performed. In the first stage, oil-in-water (O/W) nanoemulsions were prepared using soy lecithin and Tween 80 as emulsifiers, analyzing their physical stability by particle size and polydispersity index. The results show that the sonication conditions and emulsifier concentration significantly affected the creaming index and particle size. In the second stage, gels were developed from these nanoemulsions, evaluating their colorimetric and rheological properties. It was observed that the gels presented a viscoelastic behavior suitable for food applications, with a higher luminosity in protein systems. In conclusion, nanoemulsion by sonication improves the stability of canola oil, suggesting its potential use in various food applications. Additional emulsifier combinations and optimization of processing conditions are recommended to further improve the stability and functionality of the encapsulated oil. Full article

This study pertains the encapsulation of bioactive compounds, specifically phenolic compounds and lycopene, extracted from olive and tomato by-products via oil-in-water (O/W) nanoemulsions and their potential application in functional beverages. The effect of various edible oils (olive pomace oil (OPO), sunflower oil (SFO), corn oil (CO), fish oil (FO), and canola oil (CLA)) in the lipid phase and antioxidants (ascorbic acid and phenolic extracts) in the aqueous phase on the physicochemical properties of oil-in-water (O/W) nanoemulsions enriched with lycopene was evaluated, along with the bioaccessibility of the encapsulated bioactive compounds using the static INFOGEST in vitro simulation protocol for gastrointestinal food digestion. All examined edible oils led to nanoemulsions with uniform droplet sizes (droplet size < 300 nm, droplet distribution < 0.3) and high stability during storage at 4 °C, with FO being the smallest, at 259.3 ± 9.1 nm, and OPO the largest, at 286.6 ± 10.0 nm. Ascorbic acid increased the droplet size by 5–8%, improved droplet distribution, and led to a lower deterioration rate (−0.014 d⁻¹) when compared to the “control” counterparts (−0.037 d⁻¹). Lycopene bioaccessibility was significantly affected by the lipid phase, with OPO exhibiting the highest percentage (53.8 ± 2.6%) and FO the lowest (40.1 ± 2.1%). The OPO nanoemulsion was selected for the development of a functional beverage, showing excellent long-term stability. The phenolic compound concentration remained consistent during storage, and the lycopene degradation rate was minimal, at −0.0088 d⁻¹, resulting in an estimated shelf life of 165 days at 4 °C, based on a 50% reduction in lycopene content. Similarly, phenolic compounds demonstrated high bioaccessibility, without a significant dependence on the lipid phase, and stability during shelf life, enhancing the beverage’s overall antioxidant profile. These results indicate that O/W nanoemulsions are effective delivery systems for functional beverages, offering improved stability and bioaccessibility of lycopene. Full article

Oil-in-water (O/W) nanoemulsions offer significant potential for protecting and delivering sensitive ingredients such as chia seed oil, which is rich in ω-3 fatty acids (approximately 64% α-linolenic acid, ALA). This research work aimed to study the in vitro fat digestibility of chia O/W nanoemulsions (Cas1000) with 10% (w/w) of chia oil and 2% (w/w) of sodium caseinate prepared by microfluidization (1000 bar, 3 passes) and characterized through their droplet size, superficial droplet charge, and global stability. In terms of the in vitro fat digestibility, three different matrices were studied: a water solution of sodium caseinate, a chia O/W nanoemulsion, and a bulk chia oil. The particle size distribution, mean diameter, and microstructure were evaluated after in vitro stomach and small intestine simulation according to the INFOGEST method. Free fatty acids (% FFA) produced during lipolysis were quantified at the end of digestion through their neutralization by acid-base volumetric assay. The droplet size of the Cas1000 had slight changes during the gastric phase while a significant variation of this parameter was observed at the end of the intestinal phase. A higher %FFA was obtained in Cas1000 compared to bulk chia oil with values of 58.26 and 38.13%, respectively. The ALA content in the lipid phase was quantified at the end of the gastrointestinal digestion process. The results indicated no significant changes compared to the initial oil, suggesting no losses of active compounds during digestion. Full article

Essential oils (EOs) have antimicrobial properties, but their low solubility in water and strong flavor pose challenges for direct incorporation into food, as they can negatively impact organoleptic properties. To overcome these issues, strategies such as oil-in-water (O/W) nanoemulsions have been developed to improve EO dispersion and protection while enhancing antimicrobial efficacy. The objective of this study was to create sodium alginate-pink pepper essential oil (PPEO) nanoemulsions using microfluidization. Various formulations were assessed for physicochemical, physical, and antimicrobial properties to evaluate their potential in food applications. The microfluidized emulsions and nanoemulsions had droplet sizes ranging from 160 to 443 nm, polydispersity index (PdI) ranging from 0.273 to 0.638, and zeta potential (ζ) ranging from −45.2 to 66.3 mV. The nanoemulsions exhibited Newtonian behavior and remarkable stability after 20 days of storage. Antimicrobial testing revealed effectiveness against Staphylococcus aureus and Listeria monocytogenes, with minimum inhibitory concentrations (MIC) of 200 µg/mL for both microorganisms and minimum bactericidal concentrations (MBC) of 800 µg/mL and 400 µg/mL, respectively, proving that encapsulation of PPEO in nanoemulsions significantly increased its antibacterial activity. These results present the possibility of using PPEO nanoemulsions as a more effective natural alternative to synthetic preservatives in food systems. Full article

Potent synthetic drugs, as well as biomolecules extracted from plants, have been investigated for their selectivity toward cancer cells. The main limitation in cancer treatment is the ability to bring such molecules within each single cancer cell, which requires accumulation in the peritumoral region followed by homogeneous spreading within the entire tissue. In the last decades, nanotechnology has emerged as a powerful tool due to its ability to protect the drug during blood circulation and allow enhanced accumulation around the leaky regions of the tumor vasculature. However, the ideal size for accumulation of around 100 nm is too large for effective penetration into the dense collagen matrix. Therefore, we propose a multistage system based on graphene oxide nanosheet-based quantum dots (GOQDs) with dimensions that are 12 nm, functionalized with hyaluronic acid (GOQDs-HA), and deposited using the layer-by-layer technique onto an oil-in-water nanoemulsion (O/W NE) template that is around 100 nm in size, previously stabilized by a biodegradable polymer, chitosan. The choice of a biodegradable core for the nanocarrier is to degrade once inside the tumor, thus promoting the release of smaller compounds, GOQDs-HA, carrying the adsorbed anticancer compound, which in this work is represented by curcumin as a model bioactive anticancer molecule. Additionally, modification with HA aims to promote active targeting of stromal and cancer cells. Cell uptake experiments and preliminary penetration experiments in three-dimensional microtissues were performed to assess the proposed multistage nanocarrier. Full article

Nanoemulsions are gaining interest in a variety of products as a means of integrating easily degradable bioactive compounds, preserving them from oxidation, and increasing their bioavailability. However, preparing stable emulsion compositions with the desired characteristics is a difficult task. The aim of this study was to encapsulate the Tinospora cordifolia aqueous extract (TCAE) into a water in oil (W/O) nanoemulsion and identify its critical process and formulation variables, like oil (27–29.4 mL), the surfactant concentration (0.6–3 mL), and sonication amplitude (40% to 100%), using response surface methodology (RSM). The responses of this formulation were studied with an analysis of the particle size (PS), free fatty acids (FFAs), and encapsulation efficiency (EE). In between, we have studied a fishbone diagram that was used to measure risk and preliminary research. The optimized condition for the formation of a stable nanoemulsion using quality by design was surfactant (2.43 mL), oil concentration (27.61 mL), and sonication amplitude (88.6%), providing a PS of 171.62 nm, FFA content of 0.86 meq/kg oil and viscosity of 0.597 Pa.s for the blank sample compared to the enriched TCAE nanoemulsion with a PS of 243.60 nm, FFA content of 0.27 meq/kg oil and viscosity of 0.22 Pa.s. The EE increases with increasing concentrations of TCAE, from 56.88% to 85.45%. The RSM response demonstrated that both composition variables had a considerable impact on the properties of the W/O nanoemulsion. Furthermore, after the storage time, the enriched TCAE nanoemulsion showed better stability over the blank nanoemulsion, specially the FFAs, and the blank increased from 0.142 to 1.22 meq/kg oil, while TCAE showed 0.266 to 0.82 meq/kg. Full article

Recently, considerable attention has been given to using magnetic nanoparticles (MNPs) for capturing oil from oil-in-water (O/W) emulsions, despite MNPs’ inherent instability and agglomeration. Their stabilization through changing surface chemistry is required to increase dispersivity. In this research, we use cetyltrimethylammonium bromide (CTAB) as a cationic surfactant to increase the positive surface charge of the particles, resulting in a better stability in the aqueous solution because of increased repulsive forces. The functionalized MNPs are characterized using transmission electron microscopy (TEM), zeta potential, and contact angle (CA) measurements. The aim of this study is to investigate the oil separation efficiency (SE) and equilibrium oil adsorption capacity of the synthesized particles, which are determined using gas chromatography analysis. We also study the adsorption behavior using isotherm and kinetic models. The SE values indicate the superior performance of MNP@CTAB for oil adsorption from dodecane-in-water nanoemulsion (SE = 99.80%) compared to the bare MNPs with SE of approximately 57.46%. These findings are attributed to the stronger electrostatic attraction between the MNP@CTAB having high positive charge and negatively charged oil droplets. The adsorption isotherm results using both linear and non-linear regression methods show that the Freundlich isotherm is the best fit to the experimental equilibrium data (with calculated R² > 0.97), verifying a multilayer heterogeneous adsorption. Moreover, the pseudo-first-order kinetic model describes the experimental equilibrium data in a greater congruence (R² = 0.99), suggesting physical adsorption of oil onto MNPs through van der Waals and physical bonding, which is also confirmed through zeta potential measurements. Full article