High Energy Emulsification Method Research Articles

Antioxidant and anti-tyrosinase activities of quercetin-loaded olive oil nanoemulsion as potential formulation for skin hyperpigmentation

Hyperpigmentation disorders are characterized by dark spots on the skin. Treatment for hypermelanosis involves the application of tyrosinase inhibitors, chemical peels, or lasers therapy, although they may cause skin irritation and other side effects. Potential natural alternatives for skin hyperpigmentation are quercetin (QT) and olive oil (OL) due to their antioxidant activity and anti-tyrosinase property. However, QT usage drawback is its low water solubility and high chemical instability that may be overcome with nanoencapsulation. To understand if QT and OL could be used as alternative to improve hypermelanosis, we evaluated the physical-chemical and biological properties of quercetin-loaded olive oil nanoemulsion (QT-NE). QT-NE was prepared by the high-energy emulsification method and, through the Box-Behnken design, we analyzed different concentrations of OL, surfactant mixture, and the agitation speed in relation to diameter and polydispersity index (PdI). The optimized formulation was characterized in terms of size, PdI, zeta potential, pH, electrical conductivity, stability and encapsulation efficiency. Besides, we evaluated in vitro antioxidant activity, tyrosinase inhibitory activity, and in vitro toxicity. The optimized QT-NE showed a size of 183.43 ± 9.53 nm with low PdI (∼0.19), zeta potential of −17.13 ± 0.61 mV, pH around 7, conductivity of 163.96 ± 8.92 µS/cm, and high encapsulation efficiency (∼99%). The QT-NE exhibited high antioxidant activity (∼92%) and inhibited 56% of tyrosinase activity, indicating its potential for free radical scavenging and reducing skin hyperpigmentation. Furthermore, no irritation was observed by HET-CAM. Thus, this nanoemulsion (NE) is a promising alternative for hypermelanosis and could substitute the current treatments.

Phase inversion emulsification of paraffin oil/polyethylene wax blend in water: A comparison between mixed monomeric and monomeric/gemini surfactant systems

• Natural-based gemini surfactant (GS) reduced water surface tension more than Tween80. • Using GS reduced water phase volume fraction at phase inversion point (f w,inv ). • Change in f w,inv with polyethylene was alike change in phases interfacial tension. • Rheological properties of emulsions highly depended on crystallinity of oil phase. • Higher stability of emulsions was achieved by GS due to their higher zeta potential. Despite the environmental attractiveness of phase inversion emulsification, polyethylene wax-based emulsions are prepared by high-energy emulsification methods. In this research, phase inversion emulsification of paraffin oil/high density polyethylene wax (PEW) blend in water was conducted using mixed surfactants systems. Sorbitan monooleate (Span 80) was used as the oil-soluble surfactant, while either polysorbate 80 (Tween 80) or a synthesized sunflower oil-based gemini surfactant (SF6) was utilized as the water-soluble surfactant. In order to conduct phase inversion emulsification, the 85 °C water phase containing 5 wt% Tween 80 or SF6 was added to the melted oil phase containing 30 to 60 wt% PEW in the blend and 5 wt% Span 80 at 120 °C with the addition rate of 5 mL/min. Phase inversion point was detected by monitoring the dissolution of the emulsion in water during emulsification and proved by electrical conductivity measurements. A lower effectiveness was found for the mixed monomeric surfactant system compared to the gemini surfactant-containing system. For each surfactant system, the trend of change in water phase volume fraction at phase inversion point upon increase in the PEW content in the oil phase was in accordance with the trend of change in the interfacial tension between the water phase and the oil phase. Using the mixed monomeric/gemini surfactant system resulted in emulsions with larger values of absolute zeta potential and drop sizes comparable to their monomeric surfactant-containing counterparts. The absolute zeta potential of the emulsions containing 30, 50, and 60 wt% PEW in the blend was about 70, 54, and 13 mV higher in case of using the mixed monomeric/gemini surfactant system. The gemini surfactant-containing emulsions demonstrated less shear-thinning behavior and the general trend of change in their viscosity and storage modulus with formulation was in agreement with that in the enthalpy of melting of the dried emulsions. Usage of the mixed monomeric/gemini surfactant system led to higher long-term stability of the emulsions, revealed by lower rate of water evaporation from the emulsions. The results of the current study can be applied for preparation of non-polar polyethylene wax-based emulsions using phase inversion emulsification technique. This investigation also opens up the opportunity to use efficient gemini surfactants in low-energy phase inversion emulsification.

Effects of high-energy emulsification methods and environmental stresses on emulsion stability and retention of tocotrienols encapsulated in Pickering emulsions

Pickering emulsion is a promising medium for encapsulating oil-soluble bioactive. However, the effects of emulsification method on the retention of sensitive bioactive encapsulated in Pickering emulsions have often been overlooked. In this work, alginate-coated chitosan-stabilized Pickering emulsion (ACPE) was used as a medium for the microencapsulation of a highly concentrated tocotrienol-rich fraction (TRF). TRF is known to be a potent vitamin E (tocols), but it is easily oxidized. We investigated the influence of microfluidization and ultrasonication parameters on the droplet size, emulsion stability, and tocols retention upon processing and during storage. Microfluidization of the Pickering emulsions containing TRF (TRF-ACPE) at 50 MPa for one pass resulted in a monomodal size distribution with a mean droplet size of 0.96 ± 0.02 μm and a span of 1.56 ± 0.04. Further increase in the microfluidization pressure and number of passes showed negligible effect on the mean droplet size. On the contrary, ultrasonication resulted in TRF-ACPE of larger mean droplet sizes and polydispersed size distributions at all processing conditions. Moreover, higher ultrasonication intensity (90%) and longer duration (4 and 8 min) were found to induce ‘oiling-off’. The TRF-ACPEs prepared with both emulsification methods showed negligible degradation (<0.1%) of tocols upon processing. This exemplified a significant improvement in the tocols retention upon processing with a 4 to 25-fold enhancement compared to the surfactant-stabilized emulsions reported in the past literature. Our findings suggest that alginate-coated chitosan stabilized Pickering emulsion can be used to improve the stability of sensitive bioactive, which is useful for the development of functional foods. • Stable 10 wt% tocotrienols-loaded Pickering emulsion was successfully prepared. • Emulsification methods affected droplet size, emulsion stability and tocols stability. • Microfluidization produced uniform and monodispersed Pickering emulsion droplets. • Ultrasonication induced ‘oiling-off’ in the Pickering emulsion at 90% amplitude. • Pickering emulsion improved the tocols retention upon processing and during storage.

Water-in-oil high internal phase Pickering emulsions formed by spontaneous interfacial hydrolysis of monomer oil

HypothesisAlcohols can strongly reduce the interfacial tension between immiscible liquids, thus facilitating the formation of emulsions. By combining non-surface-active hydrophobic particles with medium-chain alcohols, stable water-in-oil (w/o) high internal phase Pickering emulsions (HIPPEs) can be easily prepared without high-energy emulsification methods. ExperimentsThe emulsions containing acrylate monomer as the oil phase were prepared at different pH values in the presence of hydrophobic silica particles. Further, by replacing monomer oil with organic solvents (e.g., toluene) and a certain concentration of alcohol, the promoted particle adsorption at the oil–water interface has been systematically investigated. The morphology and interfacial structure of HIPPEs were visualized by confocal laser scanning microscopy (CLSM). FindingAt high pH, stable water-in-acrylate monomer HIPPEs can be formed using commercial fumed silica nanoparticles alone with simple stirring or vortexing. The hydrolysis of the acrylate group at high pH can generate alcohols in situ which adsorb at the oil–water interface to reduce the interfacial tension and promote particle adsorption to hinder droplet coalescence. The novel strategy for forming stable and processable HIPPEs can be universally applied to different hydrophobic silica particles with the help of various alcohols as the co-stabilizer, which provides a flexible approach for the fabrication of lightweight, closed-cell solid foams for a range of applications.

THE ABILITY OF BREADFRUIT STARCH NANOPARTICLE-STABILIZED PICKERING EMULSION FOR ENCAPSULATING CINNAMON ESSENTIAL OIL

Cinnamon essential oil (CO) is susceptible to decreased stability during storage, limiting its application in food products. Pickering emulsion stabilized by starch nanoparticles becomes a potential encapsulating method that can improve CO stability. This study aimed to investigate the ability of breadfruit starch nanoparticles-stabilized Pickering emulsion to encapsulate CO with various concentrations. Encapsulation process was carried out using the high-energy emulsification method with dispersing CO (0.05%; 0.1%; 0.5%; 1% w/w) in emulsion. The loading efficiency of CO and emulsion properties were evaluated. Retention of CO was also observed in 7 days-storage. Results showed that 0.5% and 1% CO were encapsulated effectively and stable in Pickering emulsion, with loading efficiency and CO retention ranging from 79.49-81.13% and 78.86-79.20%, respectively. The addition of 0.5% and 1% CO increased yellowness (+a*: 7.45-8.99) as well as decreased whiteness (+L*: 85.77-86.06) and viscosity (629.9-721.8 cP) of Pickering emulsion. However, differences in CO concentrations did not affect the emulsion index of Pickering emulsion. These findings concluded that breadfruit starch nanoparticles-stabilized Pickering emulsion could encapsulate up to 0.5% and 1% CO with the best properties among other treatments. Therefore, breadfruit starch nanoparticles-stabilized Pickering emulsion can be an alternative as encapsulation method, which can later expand the application of CO in food products.

THE USE OF CARROT SEED OIL (DAUCUS CAROTA L.) TO FORMULATE NANOEMULGELS AS AN EFFECTIVE NATURAL SUNSCREEN AND SKIN ANTI-AGING

Objective: The purpose of this study was to develop a nanoemulgel containing vegetable oil of carrot seed oil as an effective natural sunscreen and skin anti-aging. Methods: Nanoemulgels containing 4% carrot seed oil were formulated in three formulas with different ratios of Tween 80 and Sorbitol and prepared by using the high-energy emulsification method. The nanoemulgels were determined for the organoleptic characteristic, globule size, pH, physical stability during storage for 12 w at three different temperatures (room, high and low temperature), centrifugation, and cycling test. The Sun Protection Factor (SPF) value was determined by UV spectrophotometric method and the effectiveness of anti-aging was evaluated by using a skin analyzer and the results were compared with sunscreen emulgel. Results: Nanoemulgel containing 4% carrot seed oil with a ratio of Tween 80 as surfactant and Sorbitol as co-surfactant 40 and 20 resulted in the smallest mean droplet size of 338.34 nm and the sizes were increased during 12 w of storage at room temperature but still in the nano size and this nanoemulgel did not show phase separation or still stable. These nanoemulgels were also stable after the centrifugation and cycling test. The emulgel preparation was not stable or showed phase separation after the centrifugation test. The SPF value obtained from the nanoemulgel was 20.28±0.22 and these values were higher than the sunscreen emulgel (13.94±0.27). The pore size, spot, and wrinkles of the volunteer skin were reduced after using the nanoemulgel containing 4% carrot seed. Conclusion: The sunscreen and skin anti-aging activity of nanoemulgel preparation containing 4% carrot seed oil with a ratio of surfactant Tween 80 and co-surfactant Sorbitol 40 and 20 were more effective compare with emulgel preparation.

FORMULATION AND DEVELOPMENT OF LIPID BASED NON-AQUEOUS NANO EMULSION FOR SELECTED NSAID

Oral administration of non-steroidal anti-inflammatory drugs is avoided in patients with disease like peptic ulcer, gastro esophageal reflux (GERD), irritable bowel syndrome. Administration of drug through topical route through the skin could reduce the above side effects associated with oral administered drug formulation. Hence, the aim of present study was to develop Nonaqueous Nanoemulsion (NANEs) of Naproxen for topical administration. NANEs is a multiphase colloidal dispersion heterogeneous system consist of fine nonaqueous polar solvent in oil dispersion with surfactant. NANEs of naproxen were prepared using high energy emulsification method, which break large micro droplets into nano size droplets. Drug-excipients Compatibility was studied by FT-IR. Rheology, Flow behavior, Viscosity, pH, Globule size, Drug content, in-vitro drug release of NANE were performed. For optimization of nonaqueous nanoemulsion Box- Behnken experimental design was implemented. The variables selected are phase volume ratio, surfactant concentration and stirring time. Data analysis showed that surfactant concentration and phase volume ratio significantly affect the viscosity of the formulation. From the present study, it can be concluded that a stable non-aqueous nanoemulsion can be obtained by using glycerin as dispersed phase, mineral oil as continuous phase and glycerol monostearate as surfactant, which can be used as vehicle for the water sensitive materials. This nonaqueous nanoemulsion has improved the stability of Naproxen and overcome the oral drawback associated with it.

Nanoemulsions containing Garcinia mangostana L. pericarp extract for topical applications: Development, characterization, and in vitro percutaneous penetration assay.

A highly stable oil-in-water nanoemulsion for topical applications, containing mangostins extracted from the pericarp of mangosteen (Garcinia mangostana L.), is a promising strategy to protect mangostins as well as to improve penetration of these important antioxidants through the skins. Nanoemulsions consisted of virgin coconut oil as the oil phase, Tween-80 and Span-80 as surfactants, and xanthan gum as the thickening agent, were prepared using the high-energy and low-energy emulsification methods. The nanoemulsions that were stable up to 28 days had oil droplet diameter of 220 nm to 353 nm and zeta potential of -46.9 mV to -63.7 mV. The accelerated stability test showed that the most stable nanoemulsions were those prepared using the low-energy emulsification method with an estimated shelf life of eleven months, composed of 11% oil phase, 17% surfactant, and 72% aqueous phase. The in vitro percutaneous penetration test for the nanoemulsion with added xanthan gum provided high cumulative skin penetration of mangostins of up to 114 μg/cm2. The results of this study indicate that virgin coconut oil-based nanoemulsions containing mangostins, prepared using the low-energy emulsification method, stabilized by xanthan gum and mixed at 40°C can prospectively be used for topical applications.

Ophthalmic Nanoemulsions: From Composition to Technological Processes and Quality Control.

Nanoemulsions are considered as the most promising solution to improve the delivery of ophthalmic drugs. The design of ophthalmic nanoemulsions requires an extensive understanding of pharmaceutical as well as technological aspects related to the selection of excipients and formulation processes. This Review aims at providing the readers with a comprehensive summary of possible compositions of nanoemulsions, methods for their formulation (both laboratory and industrial), and differences between technological approaches, along with an extensive outline of the research methods enabling the confirmation of in vitro properties, pharmaceutical performance, and biological activity of the obtained product. The composition of the formulation has a major influence on the properties of the final product obtained with low-energy emulsification methods. Increasing interest in high-energy emulsification methods is a consequence of their scalability important from the industrial perspective. Considering the high-energy emulsification methods, both the composition and conditions of the process (e.g., device power level, pressure, temperature, homogenization time, or number of cycles) are important for the properties and stability of nanoemulsions. It is advisible to determine the effect of each parameter on the quality of the product to establish the optimal process parameters’ range which, in turn, results in a more reproducible and efficient production.

Water-in-Oil-in-Water Nanoemulsions Containing Temulawak (Curcuma xanthorriza Roxb) and Red Dragon Fruit (Hylocereus polyrhizus) Extracts.

Hydrophobic curcumin in temulawak extract and hydrophilic betacyanin in red dragon fruit extract are high-value bioactive compounds with extensive applications in functional food. In this study, these extracts were encapsulated in water-in-oil-in-water (w/o/w) nanoemulsions as a delivery system using a two-step high-energy emulsification method. PGPR and Span 20 were used as lipophilic emulsifiers for the primary w/o emulsion. The most stable w/o/w formulation with the least oil phase separation of 5% v/v consisted of w/o emulsion (15% w/w) and Tween 80 (1.5% w/w) as hydrophilic emulsifier. The formulation was characterized by a 189-nm mean droplet diameter, 0.16 polydispersity index, and –32 mV zeta potential. The freeze–thaw stability may be attributed to the combination of low w/o emulsion content and high Tween 80 concentration in the outer water phase of the w/o/w nanoemulsions used in this study. The IC50 values of the nanoemulsion and the red dragon fruit extract were similar. It means that the higher concentration of curcumin in the nanoemulsions and the lower IC50 value of temulawak extract ensured sufficient antioxidant activities of the w/o/w nanoemulsions.

Nanoemulsion Drug Delivery System: A Review

Nano-emulsion dosage forms have nano-sized droplets of disperse phase and are kinetically stable dosage form. Nano-emulsions are included under the category of new drug delivery system containing emulsified water in oil/oil in water system having mean globule size ranges from 10 nm to 1000 nm. In the field of pharmacy, nano-emulsions play an essential role in the delivery of medication through various drug administration routes like parenteral, topical and oral route. Nano-emulsions are nano-sized emulsions which are used under high investigation as a drug carrier for enhancing the delivery of therapeutic agents. Nano-emulsions have enhanced functional properties as compared to standard emulsions. They are nowadays growing work for utilizing nano-sized particles in the research of pharmaceuticals, cosmetics and food products. Mainly, intrigue has been creating simultaneously with higher emulsification techniques and mechanisms of stabilization. Nano-emulsions are formulated by both methods like high energy emulsification or low energy emulsification methods. Rapid energy emulsification technique includes high shear mixing, high-pressure homogenization or ultrasonication. In contrast, low energy emulsification technique includes the merit of the physicochemical characteristics of the system, which exploits phase transitions to obtained nano-emulsion. This review article is an effort to summarize comparative aspects like introduction, types, advantages, disadvantages, components, factors affecting, methods of preparations, methods of analysis of nano-emulsion and applications of nano-emulsion.

Formulation and Preparation of Water-In-Oil-In-Water Emulsions Loaded with a Phenolic-Rich Inner Aqueous Phase by Application of High Energy Emulsification Methods.

Currently, industry is requesting proven techniques that allow the use of encapsulated polyphenols, rather than free molecules, to improve their stability and bioavailability. Response surface methodology (RSM) was applied in this work to determine the optimal composition and operating conditions for preparation of water-in-oil-in-water (W/O/W) emulsions loaded with phenolic rich inner aqueous phase from olive mill wastewater. A rotor-stator mixer, an ultrasonic homogenizer and a microfluidizer processor were tested in this study as high-energy emulsification methods. Optimum results were obtained by means of microfluidizer with 148 MPa and seven cycles input levels yielding droplets of 105.3 ± 3.2 nm in average size and 0.233 ± 0.020 of polydispersity index. ζ-potential, chemical and physical stability of the optimal W/O/W emulsion were also evaluated after storage. No droplet size growth or changes in stability and ζ-potential were observed. Furthermore, a satisfactory level of phenolics retention (68.6%) and antioxidant activity (89.5%) after 35 days of storage at room temperature makes it suitable for application in the food industry.

Engineering of Long-Term Stable Transparent Nanoemulsion Using High-Gravity Rotating Packed Bed for Oral Drug Delivery.

BackgroundOil-in-water drug nanoemulsion forms drug delivery systems with high oral bioavailability. The conventional fabrication methods of nanoemulsion are low energy emulsification methods and high energy emulsification methods. However, both two methods are not ideal for industrial production. The problem of low energy emulsification methods is the high dosage of surfactant and co-surfactant which has potential biosecurity issues. What is more, high energy emulsification methods have some disadvantages, like the destruction of drug components, the price of equipment and the difficulties of industrial production. Hence, there have been a few commercial drug nanoemulsions so far.MethodsIn this work, we reported a novel method for the fabrication of stable and transparent drug nanoemulsion which contains hydrophilic drug rosuvastatin (ROS) calcium or hydrophobic drug silybinin (SYN) by using high-gravity rotating packed bed (RPB). The drug nanoemulsion was systematically characterized by droplet size, size distribution, stability and in vitro drug release as well as Caco-2 cells permeability.ResultsCompared with the self-emulsification method (SE), high-gravity technology could reduce 75% amount of mixed surfactants. The as-prepared nanoemulsion exhibited a very narrow droplet size distribution with a size of 13.53 ± 0.53 nm and a polydispersity index of 0.073 ± 0.018. Meanwhile, the drug nanoemulsion was physicochemically stable at 25°C and 4°C for one-year storage. Furthermore, both ROS and SYN nanoemulsion displayed higher cell permeability and in vitro dissolution than that of commercial formulations.ConclusionThese results demonstrate that RPB can be a potential device to facilitate the industrial production of drug nanoemulsion.

Anti-Microbial Potential of Nano-Emulsion form of Essential Oil Obtained from Aerial Parts of Origanum Vulgare L. as Food Additive.

Purpose: Foodborne diseases are still a serious problem in public health and natural compounds are being widely considered for their potential industrial protective additive in food products. Origanum vulgare L. has been known as an antimicrobial effective herb. This present study was carried out to examine the antimicrobial effect of O. vulgare essential oil nanoemulsion in comparison with conventional emulsion. Methods: The essential oil was obtained by hydrodistillation, analyzed by GC-Mass and formulated as a nanoemulsion to improve water dispersion by high-energy emulsification method. The antimicrobial activity of the prepared formulation was assessed by measuring the minimum inhibitory concentration (MIC), minimum bactericidal/fungicidal concentration (MBC/MFC) and zone of inhibition against some main foodborne pathogen microorganisms. Results: The main component of the oregano essential oil was carvacrol (78%) and the selected nanoemulsion formulation demonstrated low polydispersity (0.11) and mean droplet (72.26 nm) and it was stable even after 30 days of storage. The nanoemulsion form displayed significant activity against the Staphylococcus aureus, Candida albicans and Aspergillus niger with inhibition zones ranging from 8.7–22.3 mm. The MIC of nanoemulsion against the tested bacteria was within the range of 0.156 to 0.312 (mg/mL) and against the tested fungi were in the range of 0.078 to 0.156 (mg/mL). The MBC/MFC of nanoemulsion against the tested microorganisms were in the range of 0.312 to 5 (mg/mL). Conclusion: The study’s results demonstrated the possibility of using the nanoemulsion form of oregano essential oil as a food additive to inhibit the growth of some foodborne microorganisms and extending the shelf life of food products.

Nanoformulations as a modern form of biofungicide

PurposeThe aim of this study was to elaborate new forms of biofungicide formulations which could increase biological activity of essential oil against various strains of pathogenic fungi of plants, dermatophytes, and molds.MethodsThe nanoemulsions containing four various essential oils (cinnamon, thyme, manuka, and tea tree oil) were obtained by using the low-energy (PIC) and the high-energy emulsification methods (ultrasonification). The physicochemical properties and activity of prepared systems against strains of pathogenic fungi of plants (F. culmorum, Ph. cactorum), dermatophytes (T. mentagrophytes M. gypseum) and molds (S. brevicaulis, A. niger) were examined. Fungicidal activity was tested by the method of linear growth of mycelium on an agar medium. Macroemulsions containing the oils and the pure essential oils were used as comparative samples.ResultsIt was found that nanoemulsions prepared by ultrasonification showed excellent fungicidal activity compared to pure oils and macroemulsions. Among others, the manuka oil nanoformulations showed the highest activity against the tested fungi.ConclusionsNanoemulsions can be applied as the effective carriers of essential oils. They allow the reduction of the concentration of the bioactive oils while maintaining biological activity. The obtained nanosystems can be applied as safe, biodegradable, eco-friendly antifungal products in pharmaceutical, cosmetic, and agrochemical industries as they increase the biological activity of the tested oils against various type of fungi.

Stability study of nanoemulsions of diosgenin

Nanotechnology is an interdisciplinary scientific field where it is possible to manipulate, alter and develop new materials at the nanoscale, changing their properties. In the pharmaceutical and cosmetic areas there is the production of nanocarriers for pharmaceuticals, which can protect, encapsulate and release pharmacologically active compounds. In our study we chose the nanoemulsion as carrier, since it is widely used as a vehicle for drugs, by the cosmetic and pharmaceutical industry. The drug used was Diosgenin, a steroidal sapogenin, found in roots of the wild yam (Dioscorea villosa). Diosgenin has a structure similar to progesterone and estradiol and is used as a chemical precursor in the industrial preparation of oral contraceptive pills and steroid hormones. The use of nanoemulsified diosgenin topically can bring a great number of benefits to the skin, considering its antioxidant properties and stimulating the production of collagen, thus being able to be incorporated into cosmetic anti-aging formulations. Thus, nanoemulsions can be a vehicle for diosgenin, encapsulating them, protecting them from possible degradation of the active substance and providing better permeation on the skin. The general objective was to produce and evaluate diosgenin containing nanoemulsions, aiming at the choice of a stable formulation. Nanoemulsions at concentrations 1mg.mL-1, 3 mg.mL-1 and 5 mg.mL-1 were produced using the high energy emulsification method. All formulations were submitted to different forms of storage. The characterization of the formulations allowed to evaluate the formulations of diosgenin nanoemulsions in concentrations 1 mg.mL-1, 3 mg.mL-1 and 5 mg.mL-1. The best condition for storing 1mg.mL-1 nanoemulsions without losing their physical-chemical characteristics during the 90-day period was under refrigeration. With this, there is a guarantee of the quality and stability of the diosgenin nanoemulsion, compatibility for topical use and the possibility of reaching the deeper layers of the skin, enhancing the effects of diosgenin. It was also possible to co-validate an analytical method by spectrophotometry in the visible region to identify diosgenin in nanoemulsions, ensuring the presence of the active substance in the nanoemulsion.

Preparation and Evaluation of Sunscreen Nanoemulsions with Synergistic Efficacy on SPF by Combination of Soybean Oil, Avobenzone, and Octyl Methoxycinnamate.

BACKGROUND:Soybean oil contains vitamin E and acts as a natural sunscreen which can absorb Ultra Violet (UV) B light and has antioxidant properties to reduce the photooxidative damage that results from UV-induced Reactive Oxygen Species production. The UV blocking from most natural oils is insufficient to obtain a high UV protection. The strategies for preparations of sunscreen products with high SPF can be done by nanoemulsion formulation and Ultra Violet filter combinations of Soybean Oil, Avobenzone and Octyl methoxycinnamate.AIM:The purpose of this study was to prepare and in vitro efficacy evaluation of sunscreen nanoemulsion containing Soybean oil, Avobenzone and Octyl methoxycinnamate.METHODS:The sunscreen nanoemulsions were prepared by the high energy emulsification method. The formulation uses a combination of 3% Avobenzone, 7.5% Octyl methoxycinnamate, with different ratio of Soybean oil and Liquid Paraffin. The nanoemulsion was evaluated for droplet sizes by using particle size analyzer, physical stability in room temperature (25 ± 2°C during experiment for 12 weeks of storage, physical stability (cycling test), phase separation by centrifugation at 3750 rpm for 5 hours, pH, viscosity, and Sun Protection Factor (SPF) value by UV spectrophotometric. The SPF value of sunscreen nanoemulsion was compared to sunscreen nanoemulsion without Soybean Oil and sunscreen emulsion. Particle morphology observation of nanoemulsion by using Transmission Electron Microscope.RESULTS:The sunscreen nanoemulsion formulation containing a combination of 3% Avobenzone, 7.5% Octyl methoxycinnamate with a ratio of 2.73% Soybean Oil and 0.27% Paraffin Oil resulted in the smallest average droplet size of 68.47 nm. The sunscreen nanoemulsion without Soybean Oil had an average droplet size of 384.07 nm. The globules size was increased during the experiment for 12 weeks of storage at room temperature, but there was no phase separation after centrifugation. The formulation of sunscreen emulsion, phase separation was formed after centrifugation. The nanoemulsion had a pH value of 7.23 ± 0.06 and a viscosity value of 133.33 ± 7.22 cP. The sunscreen nanoemulsion containing a combination of 3% Avobenzone, 7.5% Octyl methoxycinnamate 2.73%, Soybean Oil, 2.73% and 0.27% Liquid Paraffin had SPF value (21.57 ± 1.21) higher than sunscreen nanoemulsion without Soybean Oil (16.52 ± 0.98) and sunscreen emulsion (15.10 ± 0.22). The TEM analysis of globules morphology showed that the sunscreen nanoemulsion formed a spherical globule.CONCLUSION:The sunscreen nanoemulsion containing a combination of 3% Avobenzone, 7.5% Octyl Methoxycinnamate, 2.73% Soybean Oil and 0.27% Liquid Paraffin showed synergistic sunscreen efficacy on SPF. This sunscreen nanoemulsion is more stable than sunscreen emulsion formulation during the experiment for 12 weeks at room temperature.

Protective effect of sucupira oil nanoemulsion against oxidative stress in UVA-irradiated HaCaT cells.

Bioactive molecules derived from natural products combine the ability to absorb UV light and act as antioxidants. We developed an oil-based sucupira (native species of the Brazilian cerrado) nanoemulsion (NE) using a high-energy emulsification method and assessed its effectiveness in vitro. An easily scalable high-pressure homogenization method was used to prepare the formulation. NE droplets mean diameter, pH, stability, conductivity and morphology were analysed. Formulation bioactivity was assessed using HaCaT cells. The formulation presented suitable pH and size for topic administration and was stable for over 90days upon storage at 4, 25 and 45°C. The NE showed protective effect against oxidative stress and reduced levels of UVA-induced pro-inflammatory cytokines IL-6 and IL-8. A novel, stable and easily prepared formulation was obtained for encapsulation of sucupira oil. The protective effect of the formulation by cytokine inhibition in the early stage of the inflammatory process was shown in vitro. Combined with the antioxidant effect by inhibition of reactive oxygen species, the use of sucupira oil NE for prevention and treatment of UVA-induced stress could contribute to decrease the effects of UV radiation on skin ageing.

Optimization and Characterization of Palm Oil-based Nanoemulsion Loaded with Parthenium hysterophorus Crude Extract for Natural Herbicide Formulation.

The present study revealed the optimization of nanoemulsion containing palm oil derivatives and Parthenium hysterophorus L. crude extract (PHCE) as pre-emergence herbicide formulation against Diodia ocimifolia. The nanoemulsion formulation was prepared by high energy emulsification method, and it was optimized by mixture experimental design (MED). From the optimization process, analysis of variance (ANOVA) showed a fit quadratic polynomial model with an optimal formulation composition containing 30.91% of palm kernel oil ester (PKOE), 28.48% of mixed surfactants (Tensiofix and Tween 80, 8:2), 28.32% of water and 12.29% of PHCE. The reading of both experimental and predicted particle size in the verification experiment were acceptable with a residual standard error (RSE) was less than 2%. Under the optimal condition, the smallest particle size obtained was 140.10 nm, and the particle was shown by morphology analysis to be spherical and demonstrated good stability (no phase separation) under centrifugation and different storage conditions (25 ± 5°C and 45°C). Nanoemulsion stored for 60 days exhibits monodisperse emulsion with a slight increase of particle size. The increase in particle size over time might have contributed by Ostwald ripening phenomenon which is shown by a linear graph from Ostwald ripening rate analysis. In the in vitro germination test, P. hysterophorus nanoemulsion (PHNE) was shown to cause total inhibition of D. ocimifolia seed at lower concentration (5 g L-1) as compared to PHCE (10 g L-1). The finding of the research could potentially serve as a platform for the development of palm oil based formulation containing plant crude extract for green weed management.

Experimental investigation on the combustion, performance and emission characteristics of a diesel engine using water emulsified diesel prepared by ultrasonication

Simultaneous reduction of both nitrogen oxides (NOx) and particulate matter emission from diesel engines can be done using water emulsified diesel (WED) as fuel. Its uses in CI engines also reduce the emissions of other pollutants such as carbon monoxide (CO) and smoke. In this paper, the authors have investigated experimentally the combustion, performance and emission characteristics of a single-cylinder, four-stroke diesel engine using WED prepared by ultrasonication methods containing 10% of water and compared these with those of pure diesel. WED has been produced by high-energy emulsification method using ultrasonicator. The water particle sizes in the emulsion, polydispersity index, stability, density and viscosity of the WED have been measured for the prepared emulsion. The observations show that the ultrasonication may be considered as an acceptable method for emulsification. The combustion characteristics show that the peak in-cylinder pressure and net heat release rate are higher for WED than those of pure diesel. Longer ignition delay is found for WED than that of neat diesel. However, the combustion duration is shorter. On the other hand, pure diesel and WED are comparable with respect to power, brake thermal efficiency (BTE) and brake-specific fuel consumption (BSFC). At higher load, increased BTE and decreased neat BSFC were found in case of WED. Emissions of pollutants like NOx and smoke reduce significantly, whereas HC emission increases. No significant difference is observed in CO emission at full-load condition between pure diesel and WED.