Olive Oil In Water Research Articles

Fabricating Antibacterial Powders from Olive Oil-In Water Emulsions Stabilized by Sour Cherry-Derived Hemicellulose and Pectin Crystalline Structures

Fabricating Antibacterial Powders from Olive Oil-In Water Emulsions Stabilized by Sour Cherry-Derived Hemicellulose and Pectin Crystalline Structures

Oil-in Water Vegetable Emulsions with Oat Bran as Meat Raw Material Replacers: Compositional, Technological and Structural Approach.

The unique composition and technological properties of some oat bran components (mainly protein and soluble fiber) and olive oil make them a good choice to form oil-in-water vegetable emulsions. The different concentrations of oat bran were studied to form olive oil-in water (O/W) emulsions to apply as a replacement for fat and meat. As a result, four O/W emulsions (OBE) were formulated with 10% (OBE10), 15% (OBE15), 20% (OEB20), and 30% (OBE30) oat bran concentrations and 40% olive oil, with the corresponding amount of water added for each O/W emulsion. Composition, technological properties (thermal stability, pH, texture), and lipid structural characteristics were evaluated. The results showed that low oat bran content (OEB10)-with a lower concentration of oat protein and β-glucans-resulted in an O/W emulsion with an aggregated droplet structure and lower thermal stability and hardness. These connections between composition, technology, and structural properties of olive O/W emulsions elaborated with oat bran could help in making the optimal choice for their potential application in the production of foods such as healthier meat products.

Colloidal properties and stability of olive oil-in water emulsions stabilized by starch particles

In this study, olive oil-in-water emulsions (30% oil, v/v) were prepared by using high-pressure homogenization and different concentrations of modified corn starch particles (6–10% w/v). After a preliminary physical characterization, the modified starch particles were used to produce olive oil-in water (o/w) emulsions whose droplet size and distribution, flow behavior, microstructure, and physical stability were evaluated. The stabilization by Pickering phenomena was observed, as well as the formation of a starch network able to entrap oil particles. Increasing the starch concentration enhanced the emulsion physical stability by improving the oil particles’ stabilization within the starch network.

Comparative Protective Effects of Spirulina and Spirulina Supplemented with Thiamineagainst Sub-acute Carbon Tetrachloride Toxicity in Rats

Carbon tetrachloride (CCl4) is used extensively as an industrial solvent and considered the best-characterized experimental animal model of xenobiotic-induced hepatic toxicity via reactive oxygen species (ROS) generation. This study was designed to evaluate the protective effects of Spirulina platensis (SP) versus Spirulina platensis supplemented with thiamine (SPt) against subacute CCl4 toxicity in rats. Rats were divided into six equal groups; Control vehicle (0.5 ml/rat 1:1 olive oil in water), SP (800 mg/kg b.wt.), SPt (800 mg/kg b.wt.), CCl4 (1ml/kg b.wt.), SP + CCl4 and SPt + CCl4. All treatments were orally and daily for a month except CCl4 was given three times weekly. CCl4 caused significant reduction in body weight gain, haemoglobin content and haematocrit percentage accompanied by leukocytosis, granulocytosis, monocytosis and lymphocytopenia. Moreover, there were significant increase in the levels of serum ALT, AST; total, direct and indirect bilirubin; urea and creatinine of CCL4- intoxicated rats. CCL4- induced significant increase of malondialdehyde levels with significant reduction of catalase activity in liver and kidney. In addition, hepatic and renal various histopathological alterations were recorded. SP and SPt ameliorated almost these changes while they couldn’t reverse the reduction of body weight gains and red blood indices. The more potent effects on measured parameters were elucidated by SPt. In conclusion SP and SPt could be used as natural antioxidant supplements to counteract the CCl4 adverse effects.

FORMULATION AND CHARACTERIZATION OF FLUCONAZOLE LOADED OLIVE OIL NANO EMULSIONS

Present study was carried out to develop and evaluate olive oil based nano-emulsion for transdermal delivery of fluconazole, a bistriazole based antifungal agent with poor water solubility and lipophilicity. Olive oil, a natural non-irritating, non-toxic proposed permeation enhancer, is known to have some antifungal activity as well. Screening of common emulsifiers like Tweens (Tween 20, tween 60, tween 80), Spans (span 60, span 80), brij 35, puronic 127, and poloxamer 188 were done based on solubility of fluconazole in these surfactants followed by their efficiency to emulsify olive oil in water. Co-emulsifiers such as glycols (polyethylene glycol 200, polyethylene glycol 400, propylene glycol), and short chain alcohols (ethanol, propanol, butanol and octanol) were also screened similarly. Tween 80 and butanol were selected as emulsifier and co-emulsifier respectively to formulate nano-emulsion by aqueous titration method. However, separation was observed after 24 hours. Therefore, span 80 was added as an auxiliary emulsifier to improve emulsification efficiency. Finally, a blend of tween 80, span 80 and butanol was optimized as emulsifier (56 % wt/wt) to emulsify 9 % wt/wt of olive oil in 33 % wt/wt water. Pseudo-ternary phase diagram was employed to identify and optimize the components. Optimized formulation based on phase separation and thermokinetic stability was characterized for globule size, size distribution, zeta potential, viscosity, refractive index and pH. Globule size analysis by zetasizer nano ZS was further confirmed by transmission electron microscopy. Permeation flux of fluconazole from optimized formulation through artificial skin was approximately three fold higher than the control. In conclusion, developed olive oil based nano-emulsion of fluconazole demonstrated promising solubility, permeability and stability

Bulk and interfacial viscoelasticity in concentrated emulsions: The role of the surfactant

The aim of this study was to investigate and compare bulk and interfacial viscoelasticity of emulsions stabilized with two surfactants of a markedly different nature: the ionic phospholipids mixture Epikuron 145V and the steric emulsifier Pluronic F68. Emulsions of olive oil in water were prepared by high-pressure homogenization using only one of these surfactants. The impact of the surfactant used on the final linear viscoelastic properties was investigated by means of small-amplitude dynamic oscillatory shear tests, obtaining the values of the storage and loss moduli as a function of frequency, as well as by retardation and relaxation essays. Our results show that for concentrated emulsions, the viscoelastic properties are considerably different depending on which surfactant is used, i.e., the employed surfactant influences to a major extent the bulk rheological properties. In order to explain these differences, an interfacial study of the adsorbed surfactant layers has been carried out, measuring interfacial tension and dilatational viscoelasticity by means of the pendant drop technique. A correlation between the results obtained in bulk and interface has been found.

Polyionic hydrogels as support for immobilization of lipase

Polyionic hydrogels have been prepared by complexation of chitosan and xanthan. These hydrogels have been used to immobilize lipase from porcine pancreas (E.C. 3.1.1.3). Immobilization efficiency varied between 90 and 99% of initial activity. Immobilized lipase retained its activity towards hydrolysis of olive oil in water as an emulsion and of olive oil in isooctane.

Enhancement of enzymatic hydrolysis rate of olive oil in water by dimethyl ?-cyclodextrin

The hydrolysis rate of olive oil byCandida cylindracea lipase in an aqueous solution without surfactants can be increased up to 6-fold by the addition of up to 60 mg/ml of dimethyl β-cyclodextrin (DMCD).

Fiber optic Doppler anemometry (FODA) as a tool in formulating emulsions

Fiber optic Doppler anemometry (FODA) was used to determine the mean droplet radius and the relative number of droplets in a model olive oil emulsion. The model emulsion consisted of 40% olive oil in water with a nonionic surfactant mixture. Surfactant ratio, total surfactant concentration, and the initial distribution of the two surfactants were studied. The optimal surfactant ratio to produce the smallest mean droplet radius and the greatest relative number of droplets corresponded to an HLB of 9. The optimum total surfactant concentration was directly related to the olive oil concentration in the formulation. Also, the optimum insonation time and processing volume were determined. Droplet interactions were detected in the optimized emulsion formulation. The emulsion had a zeta potential of −36.7 mV. Replacement of a small portion of the nonionic surfactants with sodium lauryl sulfate while maintaining the overall HLB resulted in a zeta potential of −55.6 mV. Analysis by FODA indicated that the more negative surface charge increased the repulsive droplet interactions. In contrast, replacement of the nonionic surfactants with dodecyltrimethylammonium bromide resulted in a zeta potential of −17.1 mV, and enhanced attractive droplet interactions were detected by FODA.

The effect of lauryl alcohol on the stability of oil-in-water emulsions

The effect of addition of lauryl alcohol was determined on the rate at which oil was separated in an ultracentrifuge from emulsions of Nujol and of olive oil in water, stabilized with 0.2% or 0.4% sodium dodecyl sulfate (SDS). In a Nujol-water-0.2% SDS emulsion with a specific interfacial area of 1.08 × 10 4 cm 2/ml emulsified oil the stability increases with added lauryl alcohol up to 56% on the basis of the SDS, after which it remains constant. The stability of the olive oil-water-SDS emulsions is unaffected by addition of lauryl alcohol. Calculations show that the increase in stability of the Nujol emulsions can be attributed to adsorption of lauryl alcohol on areas of the oil-water interface not occupied by adsorbed SDS. The absence of any stabilizing effect in the case of the olive oil emulsions is attributed to the greater solubility of lauryl alcohol in olive oil than in Nujol.