Oil-based Emulsion Research Articles

Fabrication and characterization of emulsions stabilized by tannic acid-wheat starch complexes

Soybean oil-based emulsions stabilized by tannic acid (TA) and wheat starch (WS) complexes were prepared via a simple high-intensity ultrasound emulsification technique. The effects of mass ratio of TA/WS (0.005–0.75) and WS concentration (0.25%, 0.5% and 1.0%) on TA/WS complexes and emulsions were investigated. As the mass ratio increased, TA and WS could gradually form soluble and insoluble complexes, and their hydrophobicity also improved. Consequently, the tendency of the particle size of emulsions to decrease first and then increase appeared with the increasing mass ratio, mainly due to the changes in the contents, size and hydrophobicity of the complex emulsifier. Additionally, the emulsifying capacity of TA/WS complexes improved with increasing concentration of complexes. Moreover, the creaming was inhibited at a high mass ratio or high complex concentration due to the formation of a thick interfacial network around oil droplets or obtention of smaller-sized droplets. Emulsion gel was formed due to TA cross-linked WS on the interface within different oil droplets, and the strength of the gel increased with the mass ratio due to increasing amounts of complexes being absorbed on the interface. When the mass ratio and WS concentration were no less than 0.05 and 0.5%, respectively, emulsions had better oxidative stability. The complexes also had high resistance against droplet coalescence. This study demonstrated that TA/WS complexes could be employed as an emulsifier to improve the oxidative stability of O/W emulsions and that easily oxidized, oil-soluble nutrients or medicines could be protected and delivered through these emulsion systems.

Development and characterization of a babassu nut oil-based moisturizing cosmetic emulsion with a high sun protection factor.

A stable moisturizing cosmetic emulsion was developed from babassu nut oil and high concentrations of sunscreens. Babassu nut oil was chosen because within the laboratory time-scale, this vegetable oil showed stable physicochemical properties (relative density, acidity index, and refracted index) and a good ratio between lauric and myristic fatty acids. The presence of these saturated fatty acids can confer specific activities to the cosmetic emulsion, such as antiviral, bactericidal, and anti-inflammatory activity. The prepared cosmetic emulsion, even after the centrifugation test (3000 rpm for 15 min), showed a creamy appearance with stable light-yellow coloration and the typical odor of babassu nut oil-based products. In the accelerated stability assays (pH, viscosity, and globule homogeneity), the cosmetic emulsion was kept at different temperatures (2.0 ± 0.2 °C (TG), 25 ± 2 °C (TA), and 40 ± 2 °C (TE)) and time durations (24 hours (t0), 7 days (t7), 15 days (t15), and 30 days (t30)). Finally, developed the cosmetic emulsion was investigated for occlusive properties and in vitro sun protection factor (SPF). Both were measured at room temperature and did not change significantly under the experimental conditions employed. The maximum experimental value measured in the in vitro occlusive test was equal to 34.2 ± 2.8, and the SPF was 39 ± 1.6 (t0) and 38 ± 2.9 (t30). In agreement with European and Brazilian legislations, the obtained babassu oil-based cosmetic emulsion is classified to have a high sun protection factor.

Ultralight magnetic aerogels from Janus emulsions.

Magnetite containing aerogels were synthesized by freeze-drying olive oil/silicone oil-based Janus emulsion gels containing gelatin and sodium carboxymethylcellulose (NaCMC). The magnetite nanoparticles dispersed in olive oil are processed into the gel and remain in the macroporous aerogel after removing the oil components. The coexistence of macropores from the Janus droplets and mesopores from freeze-drying of the hydrogels in combination with the magnetic properties offer a special hierarchical pore structure, which is of relevance for smart supercapacitors, biosensors, and spilled oil sorption and separation. The morphology of the final structure was investigated in dependence on initial compositions. More hydrophobic aerogels with magnetic responsiveness were synthesized by bisacrylamide-crosslinking of the hydrogel. The crosslinked aerogels can be successfully used in magnetically responsive clean up experiments of the cationic dye methylene blue.

Neodymium pertraction through sunflower oil-based emulsion liquid membrane: stability and mass transfer investigation

Neodymium pertraction through sunflower oil-based emulsion liquid membrane: stability and mass transfer investigation

Laboratory Research on the Performance of Fracturing Fluid System for Unconventional Oil and Gas Reservoir Transformation

Fracturing fluid is the blood of fracturing construction, which is very important for fracturing, which requires that fracturing fluid needs to have good performance. The three commonly used fracturing fluids for unconventional oil and gas reservoir transformation are: 1) Guar gum fracturing fluid; 2) Water-based emulsion slippery water fracturing fluid; 3) Oil-based emulsion slippery water fracturing fluid. In this paper, water samples and other experimental data provided by Mahu Oilfield are used to evaluate three different fracturing fluid systems in laboratory. The formulas of the three different fracturing fluid systems are: 1) Water-based emulsion slippery water fracturing fluid is clean slippery water fracturing fluid 0.1% JHFR-2D drag reducer + 0.2% JHFD-2 multifunctional additive; 2) Oil-based emulsion slippery water fracturing fluid 0.1% A agent + 0.2% B agent; 3) Guar gum fracturing fluid 0.1% guanidine gum + 0.5% drainage aid + 0.3% demulsifier. The compatibility, drag reduction performance, reservoir damage, residue content, anti-swelling performance, surface interfacial tension, viscosity and other properties of three different slippery water fracturing fluid systems were studied. Through laboratory experiments, the comprehensive indicators show that clean slippery water fracturing fluid has obvious advantages.

Preparation of Squalene Oil-Based Emulsion Adjuvants Employing a Self-Emulsifying Drug Delivery System and Assessment of Mycoplasma hyopneumoniae-Specific Antibody Titers in BALB/c Mice.

In this study, a self-emulsifying drug delivery system (SEDDS) was employed to prepare novel squalene oil-based emulsion adjuvants. Deionized water, 0.01% and 0.02% (w/v) carbomer solutions of C-971P NF and C-940 grades were used to prepare emulsions containing 3%, 5% and 10% of squalene oil. Altogether 15 candidate emulsions were prepared and used as adjuvants for the delivery of a combination vaccine containing a porcine circovirus type 2 (PCV2) antigen and inactivated Mycoplasma hyopneumoniae (J101 strain) antigen. Most of the emulsions showed droplet sizes in the submicron range and maintained zeta potential values between −40 mV to 0 mV for six months, indicating good physical stability as a vaccine adjuvant. Emulsion-based candidate adjuvants prepared with SEDDS technology stimulated IgG, IgG1 and IgG2a like a currently commercially available adjuvant, Montanide ISATM 201, and they were safe and their Mycoplasma hyopneumoniae-specific antibody titers were considered as comparable with that of Montanide ISATM 201.

Pea Protein for Hempseed Oil Nanoemulsion Stabilization.

In this paper, we present the possibility of using pea protein isolates as a stabilizer for hempseed oil (HSO)-based water/oil emulsions in conjunction with lecithin as a co-surfactant. A Box-Behnken design was employed to build polynomial models for optimization of the ultrasonication process to prepare the emulsions. The stability of the system was verified by droplet size measurements using dynamic light scattering (DLS) as well as centrifugation and thermal challenge tests. The z-ave droplet diameters of optimized emulsion were 209 and 207 nm after preparation and 1 week storage, respectively. The concentration of free Linoleic acid (C18:2; n-6) was used for calculation of entrapment efficiency in prepared nanoemulsions. At optimum conditions of the process, up to 98.63% ± 1.95 of entrapment was achieved. FTIR analysis and rheological tests were also performed to evaluate the quality of oil and emulsion, and to verify the close-to-water like behavior of the prepared samples compared to the viscous nature of the original oil. Obtained results confirmed the high impact of lecithin and pea protein concentrations on the emulsion droplet size and homogeneity confirmed by microscopic imaging. The presented results are the first steps towards using hempseed oil-based emulsions as a potential food additive carrier, such as flavor. Furthermore, the good stability of the prepared nanoemulsion gives opportunities for potential use in biomedical and cosmetic applications.

Development of vegetable oil-based emulsion liquid membrane for downstream processing of bio-succinic acid

Succinic acid has been recognized as a useful platform chemical that can be applied in various industries. The application of bio-based succinic acid is still limited due to high downstream processing cost. In this study, vegetable oil-based emulsion liquid membrane (ELM) process is proposed to recover succinic acid from fermentation broth. The ELM system consists of three main liquid phases; external feed, membrane, and internal stripping. The liquid membrane phase was prepared by dissolving Amberlite LA2 and Span 80 in palm oil, while, the internal phase comprises of sodium carbonate solution, Na2CO3. The influence of feed, stripping agent and carrier concentration, treat ratio, as well as liquid membrane recycling on ELM performance were studied. The results showed 10g/L of initial concentration, 1.0M of Na2CO3, 0.7M of Amberlite LA2, and treat ratio of 1:5 is the best condition with almost 100% recovery and enrichment of 21 times. The recycled liquid membrane concentrates the succinic acid up to 12 times. Therefore, the proposed ELM is a potential technology to extract bio-succinic acid.

Low n-6/n-3 PUFA ratio improves inflammation and myocardial ischemic reperfusion injury.

This study investigated the potential effect of n-6/n-3 polyunsaturated fatty acids (PUFA) on inflammation and myocardial ischemic reperfusion injury (MIRI) in rats, together with the underlying protective mechanisms, and screen out most effective ratio of n-6/n-3 within limits. The rats with pre-infarct treatment were distributed among 5 groups according to the n-6/n-3 ratio (36:1; 1:1, 5:1, 10:1, 50:1); for the post-infarct treatment, the rats were distributed among 6 groups, including the control group (36:1) which was subjected to a sham procedure; the model group (36:1); and 4 test groups (n-6/n-3 ratio: 1:1, 5:1, 10:1, 50:1). All of the rats were fed a purple perilla seed oil and safflower oil-based fatty emulsion. The serum levels of monocyte chemoattractant protein-1 (MCP-1), interleukin (IL)-1β, IL-6, and tumor necrosis factor (TNF)-α were determined using enzyme-linked immunosorbent assay. Staining with triphenyl tetrazolium chloride, hematoxylin and eosin, or Masson's trichrome was performed for histological examination. Cardiomyocyte apoptosis was examined by TUNEL assay. Western blotting was performed to examine the expression levels of apoptosis-related proteins and signaling pathway proteins. Our data indicate that in both the pre-infarct treatment and post-infarct treatment, low ratios of n-6/n-3 PUFAs significantly inhibited the levels of serum inflammatory factors, the infarct size of MIRI rats, number of cardiomyocytes undergoing apoptosis, and the expression levels of caspase-3, Bcl-2, and Bax in the MIRI group. Thus a low ratio of n-6/n-3 PUFAs ameliorates inflammation and myocardial ischemic reperfusion injury.

Porównanie skuteczności nawilżenia skóry po zastosowaniu kremów na bazie oleju z wiesiołka i na bazie oleju arganowego

Introduction. Plant oils are valued ingredients of the oil phase of cosmetics. Argan oil is a semi-drying oil and is composed mainly of unsaturated fatty acids. It also contains saturated fatty acids and antioxidants such as tocopherols and polyphenols, among others. Evening primrose oil is rich in UFA and GLA. It is also a source of vitamins, zinc, calcium, magnesium and selenium. Skin has a protective role in the human body. The quality of its function depends on the level of hydration, among other aspects. Appropriate hydration is achieved with suitable skin care products, including natural oil-based emulsions. Aim. The aim of the study was to compare the efficacy of skin hydration for two cosmetic products: argan oil cream and evening primrose oil cream. Material and methods. The studied cosmetic products were assessed in terms of their sensory properties and qualitative composition based on information published at https://ec.europa.eu/growth/sectors/cosmetics/cosing_pl and guidelines included in the Regulation No 1223/2009. Corneometry was used to assess skin hydration and videodermatoscopy was performed. A tester applied a cream on herself for three weeks. Corneometry was performed once a week and videodermatoscopy was performed every day. Results. Corneometry assessment of evening primrose oil cream and argan oil cream indicated a significant increase in skin hydration following the use of the former. The hydration level of the skin of the hands was much lower than that of the face. The left side of the face was less hydrated than the right one. The hydration levels for both hands before and after the study were similar. Conclusions. The study demonstrated a significant impact of the cream used on the level of skin hydration. The evening primrose oil cream turned out to have strong hydrating properties. Despite unfavourable rheological characteristics, the cream did not display comedogenicity.

Carum carvi L. essential oil: A promising candidate for botanical herbicide against Echinochloa crus-galli (L.) P. Beauv. in maize cultivation

Natural, essential oil-based emulsions could be in future an alternative for synthetic herbicides. In this study, the possibility that foliar-applied caraway or peppermint essential oils (EO) can selectively inhibit the growth of Echinochloa crus-galli (L.) P. Beauv. (barnyardgrass, a typical maize weed) but not that of maize plants was tested, in attempt to develop an eco-friendly botanical herbicide. The phytotoxic potential of oil-in-water emulsions of each EO with addition of commercial adjuvant, mainly composed of fatty acids methyl esters, was examined. Their effect on visible plants injuries, biomass accumulation, chlorophyll a fluorescence and changes to biochemical patterns of both the main crop (maize) and barnyardgrass via an untargeted metabolomic approach were studied. It was found that oil-in-water emulsion containing 2.5% of adjuvant and of caraway EO did not affect significantly the growth of maize plants, did not induce foliar symptoms and did not alter the status of the photosynthetic apparatus, as revealed by chlorophyll a fluorescence. On the contrary, this emulsion exerted significantly negative effects against barnyardgrass growth, inducing foliar injuries and reducing the photosynthetic efficiency of photosystem II. It was also found that the studied emulsions caused a series of biochemical changes in the plant tissues, with caraway emulsion being more phytotoxic, as compared to the peppermint EO-emulsion. In conclusion, oil-in-water emulsion containing 2.5% of caraway EO could be used in future as a foliar-applied botanical herbicide against barnyardgrass in maize cultivation.

Coating performance and rheological characteristics of novel soybean oil-based wax emulsions

Aqueous emulsions of soybean oil-based coating materials consist of ethylene glycol and propylene glycol mono- and di-esters of stearic acid (EGMD and PGMD, respectively) and compound emulsions (mixtures of EGMD emulsion with four commercial polymer emulsions) were formulated and tested for paperboard coating. Paper coated with compound emulsions had excellent water resistance and grease resistance. With EGMD accounting for as high as 60% of the emulsion’s solid content, 5-min Cobb value of about 1.0 gsm (gram per square meter) was achieved. Increased number of drawdowns (coating) significantly improved water and grease resistance of the coated papers. With three-drawdown and coat weight of 14.93–23.00 gsm, 5-min Cobb value of less than 2 gsm and oil penetration of less than 2% were achieved. Greater heat exposure during drying resulted in better water resistance. Increasing the drying temperature from 100 to 200 °C for 30 s reduced the 5-min Cobb value of papers coated with PGMD compound emulsions from 34.1 to 1.1 gsm. The addition of cross-linking agent, zinc ammonium carbonate (ZAC), in the emulsions improved water repellency but not grease resistance. The effect of different emulsifiers on coating performance, rheology and stability of W/O and W/O/W PGMD emulsions were also investigated. The yield stress of cetyltrimethylammonium bromide (CTAB) based emulsions (1.61–21.32 Pa) were much higher than those of Tween 80 based emulsions (0.023–0.066 Pa). Both the W/O and W/O/W emulsion had higher viscosity than the compound emulsions. The compound emulsions had comparable surface energy but lower gluability compared to the commercial emulsions.

Anticancer and antibacterial effects of a clove bud essential oil-based nanoscale emulsion system.

Background and purposeThe essential oil derived from clove buds (Syzygium aromaticum) has been used as a chemopreventive agent in Ayurvedic medicine. The antiviral, antibacterial, and anticancer properties of its chemo-skeleton have motivated this study to explore its efficacy in pharmaceutics.MethodsNanoscale-based emulsions were prepared by employing a spontaneous emulsification technique through self-assembly using varying concentrations of Tween 20 and Tween 80 surfactants. Their physicochemical properties and stability were studied in order to choose an optimum formulation which was clear and stable. The cytotoxicity of the stable oil-based emulsion system was evaluated using MTT assay, colony formation assay, and Annexin V-FITC assay against the thyroid cancer cell line (HTh-7).ResultsAll three methods verified apoptosis and reduction in cancer cell proliferation, making the formulation a promising candidate as an alternative cancer drug. The oil-based emulsion system was also tested for its antibacterial properties against Staphylococcus aureus. Membrane permeability studies proved its efficacy to permeate through cell membrane, thereby increasing the leakage of cytoplasmic contents.ConclusionMany current treatments for cancers are aggressive yet ineffective. This study positions the clove bud-based nanoscale emulsion as a suitable candidate for further in vivo studies and trials as a cancer drug.

Emulsions stabilized by soy protein nanoparticles as potential functional non-dairy yogurts.

Rice bran oil and soy protein nanoparticles (SPNs) may be considered as novel functional food ingredients for soy yogurt production. Formulation of soy yogurt with SPNs and rice bran oil, which has significant physiological functions, will convert them into functional food products. This study was conducted to develop rice bran oil-based soy protein nanoparticles emulsion (SPNE) and to evaluate physical properties, antioxidant activities, oxidative stability and microbiological load as well as textural attributes of SPNs incorporated yogurt (SPNY) during storage at 4 °C for 45 days. SPNs were prepared from soy protein isolate of defatted soy flour. Solubilization, crystallization and ultrasonication was carried out six times. After the sixth cycle of repeated solubilizing, crystallization and ultrasonication, the size of nano protein was reduced to 72.42 ± 0.22 nm from 586.72 ± 0.75 nm (after first cycle). Viscosity, penetration values and water-holding capacity of SPNs added to yogurt were decreased with increase in reduction size of SPNs. SPNs added to yogurt exhibited greater antiradical scavenging ability and ferric reducing antioxidant property than control yogurt. Fortified soy yogurt had significant higher oxidative stability and proteolytic activity. Fortification of non-dairy food products with SPNs, which has significant physiological functions, convert conventional soy yogurt into functional food products. © 2019 Society of Chemical Industry.

Assessment of the microstructural characteristics and the in vitro bioactive properties of sunflower oil-based emulsions stabilized by fava bean (vicia faba) protein

Much interest is currently focused on plants such as legumes as an alternative source of protein for human nutrition. In this work a Vicia faba (fava bean, FB) protein concentrate was characterised for its ability to stabilise sunflower oil, oil-in-water (o/w) emulsions at three different pHs (3.0, 5.0 and 8.0). Emulsion microstructure was characterised by droplet size distribution (DSD) and optical microscopy, and resulting rheological properties were assessed. Smaller droplet sizes and better rheological properties (G′ and G″) were obtained at pH 3.0 and 8.0, i.e., at pH values away from the isoelectric point (pH 5.0). The in vitro bioactive properties of the emulsions at pH 3.0, 5.0 and 8.0 were tested using the ferric-reducing antioxidant power (FRAP) and the oxygen radical absorbance capacity (ORAC) antioxidant assays. The angiotensin converting enzyme (ACE) and dipeptidyl peptidase IV (DPP-IV) inhibitory activities were also determined. The highest antioxidant activity was observed when the emulsions were generated at pH 8.0 with FRAP and ORAC values of 935.7 ± 151.5 and 368.8 ± 2.3 μmol Trolox Eq. · g−1 of emulsion, respectively. Overall, the emulsions were poor inhibitors of ACE and DPP-IV. However, subjection of the emulsions to in vitro simulated gastro-intestinal digestion (SGID) released peptides which increased ACE and DPP-IV inhibitory activity (67.4 ± 2.7% and 11.2 ± 1.1%, respectively, for emulsions generated at pH 8). The emulsions generated at pH 3.0 displayed the lowest extent of lipid oxidation following 15 d storage. These results show the capability of FB protein concentrate to stabilise o/w emulsions while also demonstrating antioxidant along with ACE and DPP-IV inhibitory properties following gastrointestinal digestion.

Phospholipid-Based Reverse Micelle Structures in Vegetable Oil Modified by Water Content, Free Fatty Acid, and Temperature.

Colloidal assemblies of phospholipids in oil are known to be highly sensitive to changes in system composition and temperature. Despite the fundamental biological and high industrial relevance of these aggregates, the mechanisms behind the structural changes, especially in real oils, are not well understood. In this work, small-angle X-ray scattering (SAXS) was combined with molecular dynamics simulations to characterize the effects of oleic acid, water, and temperature on self-assembled structures formed by lecithin in rapeseed oil. SAXS showed that adding water to the mixtures caused the precipitation of liquid-crystalline phases with lamellar or hexagonal geometry. The combination of SAXS and molecular dynamics simulations revealed that stable spherical reverse micelles in oil had a core radius of about 2 nm and consisted of approximately 60 phospholipids centered around a core containing water and sugars. The presence of oleic acid improved the stability of reverse micelles against precipitation due to the increase in the water concentration in oil by allowing the reverse micelle cores to expand and accommodate more water. The shape and size of the reverse micelles changed at high temperatures, and irreversible elongation was observed, especially in the presence of oleic acid. The findings show the interdependency of the structure of the reverse micellar aggregates on system composition, in particular, oleic acid and water, as well as temperature. The revealed characteristics of the self-assembled structures have significance in understanding and tuning the properties of vegetable oil-based emulsions, food products, oil purification, and drug delivery systems.

Stability of sunflower and rapeseed oil-in-water emulsions supplemented with ethanol-treated rapeseed meal protein isolate.

A protein isolate (ERPI) was prepared from ethanol-treated rapeseed meal and used as a stabilizing agent in sunflower and rapeseed oil-in-water emulsions. The aim of the current study was to explore the influence of protein and oil concentrations on initial stability of sunflower and rapeseed oil-in-water emulsions by evaluating Gibbs free energy (ΔG) and particle size distribution. The 7-day dynamics of emulsion stability was investigated by turbidity measurement as well. A 32 factorial design was applied to assess the significance of oil (5%, 10% and 15% w/w) and ERPI protein (0.25%, 0.5% and 1.0% w/w) addition on stability of the emulsions. The results demonstrated that the increase of oil concentrations from 5 to 15% positively influenced the initial stability of sunflower and rapeseed oil-in-water emulsions. In both oil types, ERPI protein supplementation at all levels resulted in significant differences in the stability of 5% and 10% oil emulsions but did not alter the initial stability of the emulsions prepared with either 15% sunflower or rapeseed oil. With a few exceptions, there was a good agreement between Gibbs free energy data and microstructural profiles of the emulsions. Overall, emulsions with all sunflower oil concentrations and 1.0% ERPI protein exhibited better initial and a 7-day stability dynamics compared to all rapeseed oil-based emulsions. The study demonstrated the potential of ethanol-treated rapeseed meal protein isolate to serve as an emulsifying agent in sunflower and rapeseed oil containing emulsions.

Essential mint oil-based emulsions: preparation and characterization

The aim of this work is to present briefly the preparation methodology of four emulsions (named M2, M3, M6, and M7) based on extracted mint oil (Mentha Piperita) and their physical-chemical properties and quality characteristics (pH, density, acidity index, peroxide index, diene and triene content, in-time stability, humidity and fatty matter content), in order to select the most recommendable emulsion to be used in textile field. This work also underlines that the most stable emulsion is M6 emulsion followed by M3 emulsion.

Fat crystals: A tool to inhibit molecular transport in W/O/W double emulsions.

Water-in-oil-in-water (W/O/W) double emulsions are a promising technology for encapsulation applications of water soluble compounds with respect to functional food systems. Yet molecular transport through the oil phase is a well-known problem for liquid oil-based double emulsions. The influence of network crystallization in the oil phase of W/O/W globules was evaluated by NMR and laser light scattering experiments on both a liquid oil-based double emulsion and a solid fat-based double emulsion. Water transport was assessed by low-resolution NMR diffusometry and by an osmotically induced swelling or shrinking experiment, whereas manganese ion permeation was followed by means of T2 -relaxometry. The solid fat-based W/O/W globules contained a crystal network with about 80% solid fat. This W/O/W emulsion showed a reduced molecular water exchange and a slower manganese ion influx in the considered time frame, whereas its globule size remained stable under the applied osmotic gradients. The reduced permeability of the oil phase is assumed to be caused by the increased tortuosity of the diffusive path imposed by the crystal network. This solid network also provided mechanical strength to the W/O/W globules to counteract the applied osmotic forces.

Evaluation of Coconut Oil-based Emulsion Stability Using Tween-Span Type Nonionic Mixed Surfactant

Evaluation of Coconut Oil-based Emulsion Stability Using Tween-Span Type Nonionic Mixed Surfactant