Emulsion Research Articles

Novel avenue of carotenoids & omega-3 rich carrot waste extract in innovative table spread: optimization (based on texture and sensory) and characterization

Carrot waste is a rich source of pro-vitamin A, β-carotene, recognized for its immunomodulatory and health-promoting properties. The present study was aimed at formulating an innovative table spread (ITS) enriched with concentrated carotenoid extract derived from carrot pomace. Prior extraction of carotenoids in flaxseed oil was optimized resulting in extract (CE) rich in carotenoids (82.66 µg/g) and alpha-linolenic acid (ALA). The effects of three ingredients i.e. CE, tri-sodium citrate (TC), and common salt (CS) on ITS formulated using 33 factorial experiment (27 treatment combinations) were determined employing three-way ANOVA of Proc GLM method of SAS 9.3 for its textural and sensory acceptability. The optimized formulation contained 15% CE, 1.0% CS and 0.3% TC. ITS displayed medium (≈51% fat) internal phase emulsion (confirmed via fluorescence microscopy) stabilized (-56.867 mV ± 0.850 zeta potential) by whey protein concentrate and possessed high thermal stability (studied through thermogravimetric analysis). The control table spread (CTS) was prepared using all ingredients except CE replaced with flaxseed oil. ITS showed significantly (p < 0.05) higher carotenoid, antioxidant (ABTS, DPPH and FRAP), yellowness index and b* value than CTS; while non-significant (p > 0.05) difference existed for proximate composition and acidity. ITS turned out to be a naturally colored functional product and excellent source of carotenoids (24.276 μg/g ± 0.076) and ALA (13.816 g/ 100 g fat).

Osteosarcoma growth on trabecular bone mimicking structures manufactured via laser direct write

&amp;nbsp;This paper describes the direct laser write of a photocurable acrylate-based PolyHIPE (High Internal Phase Emulsion) to produce scaffolds with both macro- and microporosity, and the use of these scaffolds in osteosarcoma-based 3D cell culture. The macroporosity was introduced via the application of stereolithography to produce a classical &amp;ldquo;woodpile&amp;rdquo; structure with struts having an approximate diameter of 200 &amp;mu;m and pores were typically around 500 &amp;mu;m in diameter. The PolyHIPE retained its microporosity after stereolithographic manufacture, with a range of pore sizes typically between 10 and 60 &amp;mu;m (with most pores between 20 and 30 &amp;mu;m). The resulting scaffolds were suitable substrates for further modification using acrylic acid plasma polymerisation. This scaffold was used as a structural mimic of the trabecular bone and in vitro determination of biocompatibility using cultured bone cells (MG63) demonstrated that cells were able to colonise all materials tested, with evidence that acrylic acid plasma polymerisation improved biocompatibility in the long term. The osteosarcoma cell culture on the 3D printed scaffold exhibits different growth behaviour than observed on tissue culture plastic or a flat disk of the porous material; tumour spheroids are observed on parts of the scaffolds. The growth of these spheroids indicates that the osteosarcoma behave more akin to in vivo in this 3D mimic of trabecular bone. It was concluded that PolyHIPEs represent versatile biomaterial systems with considerable potential for the manufacture of complex devices or scaffolds for regenerative medicine. In particular, the possibility to readily mimic the hierarchical structure of native tissue enables opportunities to build in vitro models closely resembling tumour tissue.

Nanoemulsions of essential oils against multi-resistant microorganisms: An integrative review

Microbial resistance to drugs continues to be a global public health issue that demands substantial investment in research and development of new antimicrobial agents. Essential oils (EO) have demonstrated satisfactory and safe antimicrobial action, being used in pharmaceutical, cosmetic, and food formulations. In order to improve solubility, availability, and biological action, EO have been converted into nanoemulsions (NE). This review identified scientific evidence corroborating the antimicrobial action of nanoemulsions of essential oils (NEEO) against antibiotic-resistant pathogens. Using integrative review methodology, eleven scientific articles evaluating the antibacterial or antifungal assessment of NEEO were selected. The synthesis of evidence indicates that NEEO are effective in combating multidrug-resistant microorganisms and in the formation of their biofilms. Factors such as NE droplet size, chemical composition of essential oils, and the association of NE with antibiotics are discussed. Furthermore, NEEO showed satisfactory results in vitro and in vivo evaluations against resistant clinical isolates, making them promising for the development of new antimicrobial and antivirulence drugs.

Dual defense against membrane fouling for efficient and sustainable oil/water separation on a novel super-hydrophilic/underwater superoleophobic and catalytic nanofibrous membrane

Membrane separation technology is widely recognized as an efficient method for treating organically polluted wastewater in virtue of high performance and straightforward operation. However, the practical application of membranes is inevitably confronted with contamination issues, presenting a major challenge in terms of fouling resistance. To address this issue, a defensive-offensive dual-defense strategy based on wettability and catalytic ability control is proposed. With this concept, a novel nanofibrous membrane with a unique structure was successfully prepared through polyacrylonitrile (PAN) electrospinning, pre-oxidation, CoFe Prussian blue analogue (PBA) and polypyrrole (PPy) modification, and calcination processes. For the passive defense mode, the as-prepared membrane has shown good underwater-superoleophobicity for various types of oils, good separation capability for corresponding oil–water emulsions with retention ratios of above 99 % and fluxes ranging from 231.5 to 1524.2 L·m−2·h−1·bar−1, as well as organic solvent (dimethylformamide, DMF) resistance. For the offensive defense mode, this membrane exhibits well catalytic degradation performance for refractory pollutants with the assistance of peroxymonosulfate (PMS), which is due to the membrane being decorated with catalytic nanoparticles that contain abundant encapsulated ultra-small Fe doped Co3O4 (∼2.28 nm), and that is much smaller than the size of the pristine PBA (∼33.8 nm). Notably, the surfactants present in oil-in-water emulsions are found to be the main cause of membrane fouling, where the cationic surfactants exhibit the most significant fouling effect, while the introduction of photo-Fenton-like catalysis can endow the membrane with excellent antifouling performance and extended service life, and nearly a fully recover of emulsion separation performance was achieved. Overall, this work paves pathways to the design of advanced membranes for sustainable wastewater treatment.

Heterologous mRNA/MVA delivering trimeric-RBD as effective vaccination regimen against SARS-CoV-2: COVARNA Consortium

ABSTRACT Despite the high efficiency of current SARS-CoV-2 mRNA vaccines in reducing COVID-19 morbidity and mortality, waning immunity and the emergence of resistant variants underscore the need for novel vaccination strategies. This study explores a heterologous mRNA/Modified Vaccinia virus Ankara (MVA) prime/boost regimen employing a trimeric form of the receptor binding domain (RBD) of the SARS-CoV-2 spike (S) protein compared to a homologous MVA/MVA regimen. In C57BL/6 mice, the RBD was delivered during priming via an mRNA vector encapsulated in nanoemulsions (NE) or lipid nanoparticles (LNP), followed by a booster with a replication-deficient MVA-based recombinant virus (MVA-RBD). This heterologous mRNA/MVA regimen elicited strong anti-RBD binding and neutralizing antibodies (BAbs and NAbs) against both the ancestral SARS-CoV-2 strain and different variants of concern (VoCs). Additionally, this protocol induced robust and polyfunctional RBD-specific CD4 and CD8 T cell responses, particularly in animals primed with mLNP-RBD. In K18-hACE2 transgenic mice, the LNP-RBD/MVA combination provided complete protection from morbidity and mortality following a live SARS-CoV-2 challenge compared with the partial protection observed with mNE-RBD/MVA or MVA/MVA regimens. Although the mNE-RBD/MVA regimen only protects half of the animals, it was able to induce antibodies with Fc-mediated effector functions besides NAbs. Moreover, viral replication and viral load in the respiratory tract were markedly reduced and decreased pro-inflammatory cytokine levels were observed. These results support the efficacy of heterologous mRNA/MVA vaccine combinations over homologous MVA/MVA regimen, using alternative nanocarriers that circumvent intellectual property restrictions of current mRNA vaccine formulations.

A poly-δ-decalactone (PDL) based nanoemulgel for topical delivery of ketoconazole and eugenol against Candida albicans.

This study aimed to investigate the potential of poly-δ-decalactone (PDL) and a block copolymer (methoxy-poly(ethylene glycol)-b-poly-δ-decalactone (mPEG-b-PDL)) in the topical delivery of ketoconazole (KTZ) and eugenol (EUG) against Candida albicans. The nanoemulsion (NE) was studied for its significant factors and was optimized using the design of experiments (DOE) methodologies. A simple robust nanoprecipitation method was employed to successfully produce a nanoemulsion (KTZ-EUG-NE). The spherical globules exhibited rough surfaces, explaining the adsorption of mPEG-b-PDL onto PDL. The sustained drug release effects were governed by the amorphous nature of PDL. KTZ-EUG-NE was further used to develop a 1% w/v Carbopol-940-based nanoemulgel (KTZ-EUG-NE gel). The optimal rheological and spreadability properties of the developed nanoemulgel explain the ease of topical applications. Ex vivo permeation and retention studies confirmed the accumulation of KTZ-EUG-NE at different layers of the skin when applied topically. The cytotoxicity of the developed NE in human keratinocyte (HaCaT) cells demonstrated the utility of this newly explored nanocarrier in reducing the cell toxicity of KTZ. The higher antifungal activities of KTZ-EUG-NE at 19.23-fold lower concentrations for planktonic growth and 4-fold lower concentrations for biofilm formation than coarse drugs explain the effectiveness of the developed NE.

A Protocol to Determine Circadian Phase by At-Home Salivary Dim Light Melatonin Onset Assessment.

Internal circadian phase assessment is increasingly acknowledged as a critical clinical tool for the diagnosis, monitoring, and treatment of circadian rhythm sleep-wake disorders and for investigating circadian timing in other medical disorders. The widespread use of in-laboratory circadian phase assessments in routine practice has been limited, most likely because circadian phase assessment is not required by formal diagnostic nosologies, and is not generally covered by insurance. At-home assessment of salivary dim light melatonin onset (DLMO, a validated circadian phase marker) is an increasingly accepted approach to assess circadian phase. This approach may help meet the increased demand for assessments and has the advantages of lower cost and greater patient convenience. We reviewed the literature describing at-home salivary DLMO assessment methods and identified factors deemed to be important to successful implementation. Here, we provide specific protocol recommendations for conducting at-home salivary DLMO assessments to facilitate a standardized approach for clinical and research purposes. Key factors include control of lighting, sampling rate, and timing, and measures of patient compliance. We include findings from implementation of an optimization algorithm to determine the most efficient number and timing of samples in patients with Delayed Sleep-Wake Phase Disorder. We also provide recommendations for assay methods and interpretation. Providing definitive criteria for each factor, along with detailed instructions for protocol implementation, will enable more widespread adoption of at-home circadian phase assessments as a standardized clinical diagnostic, monitoring, and treatment tool.

Generation mechanism of Si–Y–B-Yb ceramics with enhanced water-oxygen corrosion resistance

This study systematically investigates the influence of preparation temperature on microstructure and generation mechanism of Si–Y–B-Yb ceramics as anti-corrosion matrix. Main phases of Si–Y–B-Yb ceramics are Y/YbB4, YSi2, and Si, where Y/YbB4 is derived from the reaction between YSi2 and YbB6. With increase in preparation temperature, open porosity of Si–Y–B-Yb ceramics gradually decreases, reaching 0.24 % at 1350 °C, and internal phases transform from a dispersed distribution to clearly defined boundary state. Based on this, high-temperature water-oxygen corrosion behavior of Si–Y–B-Yb ceramics is characterized in 50 vol% H2O+50 vol% O2 environment at 1250 °C for 100 h. In this corrosive environment, silicate phase appears on the surface of Si–Y–B-Yb ceramics. With prolonged corrosion time, silicate phase gradually forms more complete protective layer, hindering further corrosion by water-oxygen environment. These results demonstrate the feasibility of proposed Si–Y–B-Yb materials for corrosion protection.

Plant oil body as an effective improver for surimi-based 3D printing

Plant oil body (POB) is a natural oil droplet in micron- or submicron-scale covered by a specific shell composed of proteins and phospholipids, it has arisen numerous research interests in food industry due to its excellent emulsifying ability and great safety as natural product. In this study, POB has been exploited as an effective textural enhancer in surimi-based 3D food printing, and the underpinned mechanisms were investigated. First, POB with great rheological and emulsifying properties was prepared from peanuts, which behaved as a high internal phase emulsion. Second, for the first time, POB was introduced into surimi-based inks, which was able to facilitate the rearrangement of myofibrillar proteins through emulsification, thus ensuring fidelity and stability of 3D-printed surimi structures. The best printing performance was achieved at 2 % POB addition without compromising the surimi gel properties. However, excessive POB addition resulted in decreased viscosity, printing failure, and deteriorated gel characteristics. Third, a new mechanism was proposed to elucidate the interaction between POB and surimi proteins. On the one hand, POB physically filled in the gaps between proteins to increase the continuity and integrity of the surimi inks, thus improving the printability. On the other hand, POB with active surface altered the surimi protein molecular structure to boost the formation of hydrophobic interactions and disulfide bonds, leading to improved gel properties. Overall, this study demonstrated that POB was an effective improver for surimi-based 3D printing, providing new insights on developing new application of POB in food industry.

A potential acaricide of Moutan Cortex essential oil encapsulated in nanoemulsion and mesoporous silica nanoparticles against the house dust mite Dermatophagoides farinae

AbstractMoutan Cortex essential oil (MCEO) is considered to be a promising botanical insecticide. However, like most oils, MECO has several limitations, including instability and poor solubility. Nanoencapsulation technology is an excellent strategy for stabilizing essential oils because of its controlled release, enhanced efficacy, and strengthened biological activity. The present study investigated the acaricidal efficacy of pure MCEO and its encapsulated nanoemulsion (NE) and mesoporous silica nanoparticles (MSNs) against the house dust mite Dermatophagoides farinae using contact bioassays, fumigant bioassays, repellent bioassays, and the observation of toxic symptoms. MCEO-MSNs obtained in the study successfully encapsulated MCEO with an encapsulation efficiency of 63.83%. The acaricidal mortality experiments revealed that MCEO-NE and MCEO-MSN showed more significant toxicity against D. farinae than did pure MCEO. The nanomaterials showed better larvicidal and nymphicidal activities than pure MCEO at a high concentration (12-h LC90). Notably, the repellent effect experiment showed that MCEO-NE and MCEO-MSN had long-term and stable repellent effects on D. farinae, indicating the sustained release and persistence of the nanomaterials. More toxicity symptoms were observed in the IM-type group than in the KD-type group, suggesting that the MCEO nanoparticles have adverse effects on the respiratory system. Nanomaterials and MCEO promoted superoxide dismutase (SOD) activity and inhibited acetylcholinesterase (AChE) activity in D. farinae. In addition, the binding sites of paeonol to SOD and AChE were found through molecular docking. These findings demonstrate the potential of MCEO as a biological acaricide, which merits further investigation.

Construction of CS-SDAEM long-chain polysaccharide derivative on TA@CNTs coated PVDF membrane with effective oil-water emulsion purification and low contamination rate

Currently, the most effective way to improve the anti-fouling performance of water treatment separation membrane is to enhance the hydrophilicity of the membrane surface, but it can still cause contamination, leading to the occurrence of flux reduction. The construction of a strong hydration layer to resist wastewater contamination is still a challenging task. In this study, a defect-free hydration layer barrier was achieved by grafting chitosan polysaccharide derivatives (CS-SDAEM) on the membrane, which achieved in effective fouling prevention and low flux decline rate. A layer of tannic acid-coated carbon nanotubes (TA@CNTs) has been uniformly deposited on the commercial PVDF membrane so that the surface was rich in -COOH groups, providing sufficient reaction sites. These reactive groups facilitate the grafting of amphiphilic polymers onto the membrane. This modification strategy achieved in enhancing the antifouling performance. The modified membrane achieved low contamination rate with DR of 16.9 % for wastewater filtration, and the flux recovery rate was above 95 % with PWF of 1100 (L·m−2·h−1). The membrane had excellent anti-fouling performance, which provided a new route for the future development of water treatment membrane.

Enhancing bioactivity of Callistemon citrinus (Curtis) essential oil through novel nanoemulsion formulation

The main focus of this study was to create a stable and efficient nanoemulsion (NE) using Callistemon citrinus essential oil (EO). Various factors affecting the NE’s stability were optimized including oil %, Tween 80%, time of sonication, and its accelerated stability was examined. The research also considered the antibacterial, antifungal, and larvicidal effects of the optimized NE (B10). The optimum NE stood out for its stability, featuring a particle size of 33.15 ± 0.32 nm. Analysis via IR spectroscopy confirmed successful EO encapsulation in B10. The formulation remained stable for six months, with B10 showing significantly higher antibacterial and antifungal potency compared to the pure oil. When samples were subjected to tests against Fusarium oxysporum, B10 exhibited a MIC value of 62.5 mg/mL, whereas the pure oil showed a MIC value of 250 mg/mL. This indicates that the B10 formulation was 50 times more effective than the EO. In terms of antibacterial activity against Escherichia coli, the MIC value was 0.256 mg/mL for B10 and 4 mg/mL for the EO. Also, pure oil and B10 displayed larvicidal effects against Chilo suppressalis (Walker) larvae, with B10 eliminating 95.2% of larvae in 48 h. Overall, stable and optimum C. citrinus NE with its strong antimicrobial qualities, shows promise as an effective fungicide and insecticide.

Construction of Nano-Janus emulsion by phase inversion composition

Nano-Janus emulsion possesses excellent solubilization capabilities of both aqueous and organic materials, various liquid–liquid interfaces, and precisely controllable morphology. Successful construction of nano Janus droplets at mild conditions of room temperature and low-energy input will expand the industrial application. Two immiscible liquids of silicone oil (SO) and oleic acid (OA) are used as internal phases, and water is added dropwise at mild temperature. The topology of the nano-sized complex droplets is characterized by cryo-TEM, SAXS, and FF-TEM. Micro structure of lamellar liquid crystal (Lα), which is the critical transition phase, is investigated to reveal the formation mechanism. Topology adjustment including size range, volume ratio, and interface curvature is investigated. Complex nano droplets with snowman shape are successfully constructed in batch-scale at mild temperature of 30 °C and water-dripping rate of 1.0 mL/h. Formation of a four-component Lα phase is the critical point to the successful construction of the nano-Janus emulsion, which also creates additional freedom for structural regulation. The size of the complex droplets is freely alternated in the range of 50–500 nm and the morphology of one lobe is controlled from “crescent” to “half-moon”, and “moon with a hole”.

Bioactive polymer composite scaffolds fabricated from 3D printed negative molds enable bone formation and vascularization

Scaffolds for bone defect treatment should ideally support vascularization and promote bone formation, to facilitate the translation into biomedical device applications. This study presents a novel approach utilizing 3D-printed water-dissolvable polyvinyl alcohol (PVA) sacrificial molds to engineer polymerized High Internal Phase Emulsion (polyHIPE) scaffolds with microchannels and distinct multiscale porosity. Two sacrificial mold variants (250 µm and 500 µm) were generated using fused deposition modeling, filled with HIPE, and subsequently dissolved to create polyHIPE scaffolds containing microchannels. In vitro assessments demonstrated significant enhancement in cell infiltration, proliferation, and osteogenic differentiation, underscoring the favorable impact of microchannels on cell behavior. High loading efficiency and controlled release of the osteogenic factor BMP-2 were achieved, with microchannels facilitating release of the growth factor. Evaluation in a mouse critical-size calvarial defect model revealed enhanced vascularization and bone formation in microchanneled scaffolds containing BMP-2. This study not only introduces an accessible method for creating multiscale porosity in polyHIPE scaffolds but also emphasizes its capability to enhance cellular infiltration, controlled growth factor release, and in vivo performance. The findings suggest promising applications in bone tissue engineering and regenerative medicine, and are expected to facilitate the translation of this type of biomaterial scaffold. Statement of significanceThis study holds significance in the realm of biomaterial scaffold design for bone tissue engineering and regeneration. We demonstrate a novel method to introduce controlled multiscale porosity and microchannels into polyHIPE scaffolds, by utilizing 3D-printed water-dissolvable PVA molds. The strategy offers new possibilities for improving cellular infiltration, achieving controlled release of growth factors, and enhancing vascularization and bone formation outcomes. This microchannel approach not only marks a substantial stride in scaffold design but also demonstrates its tangible impact on enhancing osteogenic cell differentiation and fostering robust bone formation in vivo. The findings emphasize the potential of this methodology for bone regeneration applications, showcasing an interesting advancement in the quest for effective and innovative biomaterial scaffolds to regenerate bone defects.

Development of Prangos ferulacea essential oil based nanoemulsions/pickering emulsion and examination of their performance in mayonnaise shelf life

The increasing demand to replace chemical antimicrobial agents with natural compounds leads to the use of some plant extracts and essential oils (EOs) as natural preservatives. Nanoemulsion (NE) with Tween 80 as wall material and Pickering emulsions (PE) stabilized with carbohydrate (Arabic gum (AG)) or protein (sodium caseinate (SC)) wall materials. First of all, the PEO was obtained from two parts of plant: flowers and leave, and characterized by GC-MS and the IC50 index measurement. The Prangos ferulacea essential oil (PEO) extracted from leave was selected for the next tests due to slightly higher antioxidant activity compared to the flower's EO. The leave's PEO was encapsulated in three forms: nanoemulsion (NE) with Tween 80 as wall material and Pickering emulsions (PE) stabilized with carbohydrate (gum Arabic (GA)) or protein (sodium caseinate (SC)) wall materials. The NE had the smallest particle size and the highest antioxidant and antimicrobial (S. aureus and E. coli) activity. AG-stabilized PE recorded the highest encapsulation efficiency (85.37 ± 1.97 %). The occurring of new chemical interactions between PEO and wall materials and uniformly shaped PE microcapsules were approved by FT-IR and FE-SEM tests, respectively. Free and encapsulated PEO were added to the mayonnaise, and the samples were analyzed during storage at 4 °C for 60 days. Peroxide value and TBA index gradually increased for all mayonnaise samples, but this increase was lower for samples containing NE and SC-stabilized PEO capsules. In general, carriers stabilized with the simultaneous application of protein and carbohydrate performed better compared to their single application in sensory tests in mayonnaise.

Insight into the role of droplets in quinoa starch-based Pickering high internal phase emulsion for enzymatic hydrolysis reaction

Pickering high internal phase emulsion has emerged as potential platforms for biocatalytic reactions. Herein, native quinoa starch was used as the emulsifier to form a stable Pickering HIPE with an internal phase up to 80 %. The catalytic performance of lipase loaded in HIPE was evaluated for the enzymatic hydrolysis of hexyl hexanoate. Compared with the typical Pickering emulsion, biphasic, and monophasic systems, the Pickering HIPE system displayed higher conversion (83.54 % at 1440 min) and specific enzyme activity (1.41 U/mg), thus emphasizing the crucial role of microdroplets and large interface area created by both the starch particles and high internal phase volume. Subsequently, HIPEs with different starch concentrations were fabricated to further understand the catalysis behavior happening at compartmentalized microdroplets and interfaces. The microstructural, interfacial, and rheological properties of the HIPEs were systematically determined to explain the correlation between emulsion properties and catalytic efficiency. High starch concentration reduced the droplet size and increased the interfacial area, thus shortening the mass transfer distance and enlarging the reaction area. Meanwhile, the increased surface coverage and viscosity led to poor accessibility and limited mass movement. This trade-off made the maximum conversion be obtained at 2 wt% concentration. The study provides novel information about the role of emulsion droplets in the catalytic performance of lipase in starch-based HIPE.

Fabrication and evaluation of nanoemulsionbased insulin loaded microneedles for transdermal drug delivery.

Aim: Insulin therapy require self-administration of subcutaneous injection leading to painful and inconvenient drug therapy. The aim is to fabricate nanoemulsion (NE)based insulin loaded microneedles with improved bioavailability and patient compliance.Materials & methods: Different ratios of polyvinyl alcohol and polyvinylpyrrolidone as polymers were prepared through micro-molding technique for microneedles. Characterization of were performed using scanning electron microscope, differential scanning calorimetry, Fourier-transform infrared spectroscopy and circular dichroism. Mechanical strength, hygroscopicity and pain perception of these microneedles were also evaluated. Invitro release, permeation and in vivo PK/PD study of NE-based microneedles were conducted.Results: NE-based microneedles of insulin have improved bioavailability and quick response.Conclusion: Microneedles loaded with insulin can be effectively delivered insulin transdermally to treat diabetes with increased convenience and patient compliance.

Characterization of bamboo shoot cellulose nanofibers modified by TEMPO oxidation and ball milling method and its application in W/O emulsion

It has rarely been reported that the modification of bamboo shoot nanofibers by oxidation combined with physical and applied in food emulsions. In this study, the combination of 2,2,6,6-tetramethylpiperidine-1-oxyl radical (TEMPO)-mediated oxidation and the ball milling technique was employed to prepare bamboo shoot cellulose nanofibers (TOCNF) for W/O emulsions. A comparative study of the properties and structures of CNF prepared only by ball milling and TOCNF prepared by oxidation-ball milling was carried out, and a preliminary structural and rheological study of their application to emulsions was carried out. The results showed that TOCNF had higher water holding, swelling, and oil holding properties, cholesterol and glucose adsorption capacity than CNF. The combination of oxidative pretreatment and ball milling resulted in a dense entangled network structure, uniform particle size distribution, and high zeta potential value of TOCNF. The higher crystallinity of the TOCNF (68%) resulted in improved thermal stability. In addition, compared with the CNF-stabilized emulsion, with TOCNF dispersion as the internal aqueous phase, the emulsion droplets had a more uniform particle size distribution (6.61 ± 3.59 μm), higher gel strength, and thixotropic resilience of up to 71.24%. Thus, TEMPO oxidation combined with the ball milling method can be an effective means to improve nanofibers and provide a theoretical basis for expanding the application of bamboo shoot cellulose resources in the food colloid field.

Eco-friendly, highly interpenetrated and slightly swollen pHEMA hydrogel foam for durable underwater superoleophobicity and emulsion separation

Despite the emergence of hydrogels as ideal candidates for preparing the superhydrophilic materials for emulsion separation, their structural stability and swelling still hinder their long-term use, mainly due to structure defects after swelling. Herein, differing from the common modification, the eco-friendly poly 2-hydroxyethyl methacrylate (pHEMA) hydrogel foam was designed and synthesized via a one-step strategy by using the high internal phase emulsion (HIPE) template method, which endowed it with a highly interpenetrated porous structure. Unlike the normal swellable hydrogels such as poly(N-isoproplyacrylamide) (PNIPAM) hydrogel, or modified hydrogel coatings, the pHEMA hydrogel foam displayed stable structure and underwater superoleophobicity after 20 d of immersion in water. The pHEMA hydrogel foam could separate different kinds of highly surfactant-stabilized oil-in-water (O/W) emulsions with a high separation efficiency of 99.3% for liquid paraffin emulsion obtained solely under gravity-driven. Additionally, it exhibited excellent antifouling performance and long-term acid/alkali tolerance over 100 h without decrease in emulsion separation efficiency (98.0%, oil/water ratio of 99:1) and permeation flux (over 2000 L·m−2·h−1) attributed to its stable bulky structure. Moreover, the pHEMA hydrogel foam demonstrated high cell viability of 96.87% and 95.96% after culturing the 3T3 clone A31 cells in the pHEMA hydrogel foam for 24 h and 48 h, respectively, indicating good biocompatibility. Hence, our work provides a new design to develop an eco-friendly bulk hydrogel foam that achieves stable structure and performance for emulsion separation.

Preparation and Properties of Walnut Protein Isolate-Whey Protein Isolate Nanoparticles Stabilizing High Internal Phase Pickering Emulsions.

To enhance the functional properties of walnut protein isolate (WalPI), hydrophilic whey protein isolate (WPI) was selected to formulate WalPI-WPI nanoparticles (nano-WalPI-WPI) via a pH cycling technique. These nano-WalPI-WPI particles were subsequently employed to stabilize high internal phase Pickering emulsions (HIPEs). By adjusting the mass ratio of WalPI to WPI from 9:1 to 1:1, the resultant nano-WalPI-WPI exhibited sizes ranging from 70.98 to 124.57 nm, with a polydispersity index of less than 0.326. When the mass ratio of WalPI to WPI was 7:3, there were significant enhancements in various functional properties: the solubility, denaturation peak temperature, emulsifying activity index, and emulsifying stability index increased by 6.09 times, 0.54 °C, 318.94 m2/g, and 552.95 min, respectively, and the surface hydrophobicity decreased by 59.23%, compared with that of WalPI nanoparticles (nano-WalPI), with the best overall performance. The nano-WalPI-WPI were held together by hydrophobic interactions, hydrogen bonding, and electrostatic forces, which preserved the intact primary structure and improved resistance to structural changes during the neutralization process. The HIPEs stabilized by nano-WalPI-WPI exhibited an average droplet size of less than 30 μm, with droplets uniformly dispersed and maintaining an intact spherical structure, demonstrating superior storage stability. All HIPEs exhibited pseudoplastic behavior with good thixotropic properties. This study provides a theoretical foundation for enhancing the functional properties of hydrophobic proteins and introduces a novel approach for constructing emulsion systems stabilized by composite proteins as emulsifiers.