Processing and Formulation Optimization of Mandarin Essential Oil-Loaded Emulsions Developed by Microfluidization

Emulsions can be used as delivery systems for bioactive ingredients for their incorporation in food products. Essential oils are natural compounds found in plants that present antioxidant and antimicrobial activity. Therefore, the main goal of this work was to develop emulsions, containing mandarin essential oil stabilized by two food-grade surfactants and guar gum, and to evaluate their physical stability. The initial droplet size of emulsions developed by microfluidization was optimized, obtaining diameters below one micron regardless of the processing conditions. However, the emulsion processed at 25,000 psi and one pass exhibited the lowest mean droplet sizes and polidispersity, and therefore, a higher stability. Different ratios of Tween 80 and Span 80 were assessed as stabilizers. Results obtained indicated that the ratio of surfactants had a significant effect on the mean droplet sizes, physical stability, and rheological properties. Thus, we found that the optimum ratio of surfactants was 75/25 (Tween80/Span80) on account of the lowest droplet mean diameters, lack of coalescence, and a low creaming rate. The rheological characterization of the stable emulsions showed a shear thinning flow behavior, and G″ (loss modulus) values higher than G′ (storage modulus) values, in all the frequency range. The rheological behavior may be governed by the guar gum, which was confirmed by field emission scanning electron microscopy (FESEM). This research can be considered as the starting point for future applications of mandarin essential oil in emulsions, which can be incorporated in products as food preservatives.

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D-optimal design of experiments and comprehensive rheological analysis in the development of natural anti-aging creams

Advanced technologies ◽

10.5937/savteh2002029s ◽

2020 ◽

Vol 9 (2) ◽

pp. 29-40

Author(s):

Sanela Savić ◽

Nebojša Cekić ◽

Saša Savić

Keyword(s):

Structural Change ◽

Optimal Design ◽

Yield Point ◽

Loss Modulus ◽

Flow Behavior ◽

Physical Stability ◽

Mutual Effect ◽

Elastic Behavior ◽

Rheological Characterization

This work is focused on the development and evaluation of completely natural anti-aging creams, with the aid of the experimental design. Model formulations, differing in the content of emollients (10%/15%/20%) and emulsifier (1%/2%/3%) and containing the Acmella oleracea extract as a model anti-aging active were prepared by the cold process and evaluated regarding rheological behavior (con-tinuous rotational and oscillatory tests) and physical stability (dynamic-mechanical thermoanalysis-DMTA test). To study the influence of varied formulation parameters and their interaction on the critical rheological characteristics of the developed creams, a D-optimal design within the response surface method was applied. The data acquired from rheological characterization revealed favorized pseudoplastic (shear-thinning) flow behavior with the yield point, and dominating elastic behavior (storage modulus G' > loss modulus G") in both, amplitude and frequency sweeps, which together with a rather small and constant structural change obtained in the DMTA test indicated satisfying overall physical stability of formulated creams. The results of D-optimal design showed a significant individual, as well as a mutual effect of the tested formulation factors (emollient concentration, emulsifier concentration) affecting critical quality attributes (apparent viscosity, yield point, flow point, G', G", structural change) of developed anti-aging creams. Based on optimization results, the model formulation containing 20% of the emollient mixture and 2% of the emulsifier was selected as preferred in terms of required rheological properties and, thus, desired stability and quality, and it could be considered as a promising candidate worth exploring further for efficacy and in vivo skin performances.

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Rheological Characterization of Hydrogels from Alginate-Based Nanodispersion

Polymers ◽

10.3390/polym11020259 ◽

2019 ◽

Vol 11 (2) ◽

pp. 259 ◽

Cited By ~ 20

Author(s):

Francesca Cuomo ◽

Martina Cofelice ◽

Francesco Lopez

Keyword(s):

Essential Oil ◽

Tween 80 ◽

Creep Recovery ◽

Ion Release ◽

Rheological Characterization ◽

Burger Model ◽

Food Industries ◽

Hydrogel Network

The interest toward alginate and nanoemulsion-based hydrogels is driven by the wide potential of application. These systems have been noticed in several areas, ranging from pharmaceutical, medical, coating, and food industries. In this investigation, hydrogels prepared through in situ calcium ion release, starting from lemongrass essential oil nanodispersions stabilized in alginate aqueous suspensions in the presence of the nonionic surfactant Tween 80, were evaluated. The hydrogels prepared at different concentrations of oil, alginate, and calcium were characterized through rheological tests. Flow curves demonstrate that the hydrogels share shear thinning behavior. Oscillatory tests showed that the strength of the hydrogel network increases with the crosslinker increase, and decreases at low polymer concentrations. The hydrogels were thixotropic materials with a slow time of structural restoration after breakage. Finally, by analyzing the creep recovery data, the hydrogel responses were all fitted to the Burger model. Overall, it was demonstrated that the presence of essential oil in the proposed hydrogels does not affect the mechanical characteristics of the materials, which are mainly influenced by the concentration of polymer and calcium as a crosslinker.

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Rheological Properties of Alginate–Essential Oil Nanodispersions

Colloids and Interfaces ◽

10.3390/colloids2040048 ◽

2018 ◽

Vol 2 (4) ◽

pp. 48 ◽

Cited By ~ 4

Author(s):

Martina Cofelice ◽

Francesca Cuomo ◽

Francesco Lopez

Keyword(s):

Wound Healing ◽

Essential Oil ◽

Flow Behavior ◽

Tween 80 ◽

Frequency Sweep ◽

Rheological Analysis ◽

Oscillatory Frequency ◽

Healing Tissue ◽

Thixotropic Behavior ◽

Newtonian Behavior

Due to its favorable structural properties and biocompatibility, alginate is recognized as a suitable versatile biopolymer for use in a broad range of applications ranging from drug delivery, wound healing, tissue engineering, and food formulations such as nanodispersions. Rheological analysis plays a crucial role in the design of suitable nanoemulsion based coatings. Different essential oil and alginate nanodispersion compositions stabilized by Tween 80 were analyzed for rheological and conductometric properties. The results confirmed that the nanoformulations shared a pseudoplastic non-Newtonian behavior that was more evident with higher alginate concentrations (2%). Nanodispersions made of alginate and essential oil exhibited a slight thixotropic behavior, demonstrating the aptitude to instantaneously recover from the applied stress or strain. Oscillatory frequency sweep tests showed a similar fluid-like behavior for 1% and 2% alginate nanodispersions. Finally, it was demonstrated that advantages coming with the use of the essential oil are added to the positive aspects of alginate with no dramatic modification on the flow behavior.

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Application of CMC as Thickener on Nanoemulsions Based on Olive Oil: Physical Properties and Stability

International Journal of Polymer Science ◽

10.1155/2016/6280581 ◽

2016 ◽

Vol 2016 ◽

pp. 1-10 ◽

Cited By ~ 18

Author(s):

C. Arancibia ◽

R. Navarro-Lisboa ◽

R. N. Zúñiga ◽

S. Matiacevich

Keyword(s):

Physical Properties ◽

Olive Oil ◽

Flow Behavior ◽

Average Particle Size ◽

Physical Stability ◽

Tween 80 ◽

Gelling Agent ◽

Average Particle ◽

Anionic Charge ◽

Oil Concentration

Carboxymethyl cellulose (CMC) is a hydrocolloid with surface activity that could act as emulsifiers in oil-in-water emulsions; however the principal role is that it acts as structuring, thickening, or gelling agent in the aqueous phase. This study aims to evaluate the application of CMC as thickener into nanoemulsions based on olive oil and their influence on particle characteristics, flow behavior, and color. Four nanoemulsions with different oil (5% and 15% w/w olive oil) and CMC (0.5% and 0.75% w/w) concentration and two control samples without CMC added were prepared using Tween 80 as emulsifier. All physical properties studied on nanoemulsions were depending on both oil and CMC concentration. In general, z-average particle size varied among 107–121 nm and those samples with 5% oil and CMC were the most polydisperse. The addition of CMC increased anionic charge of nanoemulsions obtaining zeta potential values among −41 and −55 mV. The oil concentration increased both consistency and pseudoplasticity of samples, although samples were more stable to gravitational separation at the highest CMC concentration. Color of nanoemulsions was affected principally by the oil concentration. Finally, the results showed that CMC could be applied in nanoemulsions as thickener increasing their physical stability although modifying their physical properties.

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Impact of Microfluidization on the Emulsifying Properties of Zein-Based Emulsions: Influence of Diutan Gum Concentration

Materials ◽

10.3390/ma14133695 ◽

2021 ◽

Vol 14 (13) ◽

pp. 3695

Author(s):

Jenifer Santos ◽

Luis A. Trujillo-Cayado ◽

María del Águila Alcaide ◽

María del Carmen Alfaro

Keyword(s):

Response Surface Methodology ◽

Response Surface ◽

Preparation Method ◽

Physical Stability ◽

Emulsifying Properties ◽

Gel Properties ◽

3D Network ◽

Starting Point ◽

Processing Variables ◽

Droplet Sizes

Microfluidization is a preparation method that can be used to obtain emulsions with submicron droplet sizes. The first objective of this study was to evaluate the influence of homogenization pressure and cycles on droplet sizes using response surface methodology. Secondly, the influence of the diutan gum concentration incorporated in the optimized emulsion on rheological properties, microstructure, and physical stability was investigated. Taking the response surface analysis into account, the emulsion processed at 20,000 psi after four cycles seemed to show the smallest Sauter diameter values. Hence, this emulsion was the starting point to incorporate diutan gum. Interestingly, the formation of a 3D network in the emulsion, observed by FESEM, was provoked by diutan gum. The emulsion formulated with 0.4 wt.% of diutan gum presented rheological gel properties and enhanced physical stability. This work highlights the importance of selecting optimized processing variables using the microfluidization technique and extends the knowledge of using diutan gum in combination with zein.

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PERILAKU DISOLUSI KETOPROFEN DAN INDOMETASIN FARNESIL TERSALUT GEL KITOSAN-GOM GUAR

Jurnal Sains dan Teknologi Indonesia ◽

10.29122/jsti.v12i1.849 ◽

2012 ◽

Vol 12 (1) ◽

Author(s):

Purwantiningsih Sugita ◽

Bambang Srijanto ◽

Budi Arifin ◽

Fithri Amelia ◽

Mahdi Mubarok

Keyword(s):

Room Temperature ◽

Guar Gum ◽

Tween 80 ◽

Chitosan Solution ◽

In Vitro Dissolution ◽

Dissolution Profile ◽

Magnetic Stirrer ◽

Dissolution Behaviour ◽

Shrimp Shell Waste

Chitosan, a modification of shrimp-shell waste, has been utilized as microcapsule. However, it’s fragile gel property needs to be strengthened by adding glutaraldehyde (glu) and natural hydrocolloid guar gum (gg). This research’s purposes were to study dissolution behaviour of ketoprofen and infar through optimum chitosan-guar gum microcapsule. Into 228.6 mL of 1.75% (w/v) chitosan solution in 1% (v/v) acetic acid,38.1 mL of gg solution was added with concentration variation of 0.35, 0.55, and 0.75% (w/v) for ketoprofen microcapsules and 0.05, 0.19, and 0.33% (w/v) for infar microcapsules, and stirred with magnetic stirrer until homogenous. Afterwards, 7.62mL of glu was added slowly under stirring, with concentrations varied: 3, 3.5, and 4% (v/v) for ketoprofen microcapsules, and 4, 4.5, and 5% (v/v) for infar microcapsules. All mixtures were shaked for 20 minutes for homogenization. All mixtures wereshaked for 20 minutes for homogenization. Into each microcapsule mixture for ketoprofen, a solution of 2 g of ketoprofen in 250 mL of 96% ethanol was added, whereas solution of 100 mg of in 250 mL of 96% ethanol was added into each microcapsule mixture for infar. Every mixture was then added with 5 mL of 2% Tween-80 and stirred with magnetic stirrer for an hour at room temperature. Everymixture was then added with 5 mL of 2% Tween-80 and stirred with magnetic stirrer for an hour at room temperature. Conversion of suspension into fine powders/granules (microcapsules) was done by using spray dryer. The data of [gg], [glu], and medicine’s content from each microcapsule were treated with Minitab 14 software to obtain optimum [gg] and [glu] for microencapsulation. The dissolution behaviour of optimum ketoprofen and infar microcapsules were investigated. The result of optimization by using Minitab Release 14 software showed that among the microcapsule compositions of [gg] and [glu] were 0.35% (w/v) and 3.75% (v/v), respectively, optimum to coat ketoprofen, whereas [gg] and [glu] of 0.05% (w/v) and4.00% (v/v), respectively, optimum to coat infar, at constant chitosan concentration (1.75% [w/v]). In vitro dissolution profile showed that chitosan-guar gum gel microcapsule was more resistant in intestinal pH condition (rather basic) compared with that in gastric pH (very acidic).

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Rheological Characterization of a Concentrated Phosphate Slurry

Fluids ◽

10.3390/fluids6050178 ◽

2021 ◽

Vol 6 (5) ◽

pp. 178

Author(s):

Souhail Maazioui ◽

Abderrahim Maazouz ◽

Fayssal Benkhaldoun ◽

Driss Ouazar ◽

Khalid Lamnawar

Keyword(s):

Flow Behavior ◽

Continuous Phase ◽

Raw Material ◽

Rheological Characterization ◽

Phosphate Ore ◽

Insoluble Particles ◽

Experimental Protocols ◽

Solid Liquid

Phosphate ore slurry is a suspension of insoluble particles of phosphate rock, the primary raw material for fertilizer and phosphoric acid, in a continuous phase of water. This suspension has a non-Newtonian flow behavior and exhibits yield stress as the shear rate tends toward zero. The suspended particles in the present study were assumed to be noncolloidal. Various grades and phosphate ore concentrations were chosen for this rheological investigation. We created some experimental protocols to determine the main characteristics of these complex fluids and established relevant rheological models with a view to simulate the numerical flow in a cylindrical pipeline. Rheograms of these slurries were obtained using a rotational rheometer and were accurately modeled with commonly used yield-pseudoplastic models. The results show that the concentration of solids in a solid–liquid mixture could be increased while maintaining a desired apparent viscosity. Finally, the design equations for the laminar pipe flow of yield pseudoplastics were investigated to highlight the role of rheological studies in this context.

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Certain Rheological Aspects of Functionalized Guar Gum

International Journal of Carbohydrate Chemistry ◽

10.1155/2013/463907 ◽

2013 ◽

Vol 2013 ◽

pp. 1-15 ◽

Cited By ~ 3

Author(s):

Meenu Kapoor ◽

Dhriti Khandal ◽

Ruchi Gupta ◽

Pinklesh Arora ◽

Geetha Seshadri ◽

...

Keyword(s):

Molecular Weight ◽

Shear Rate ◽

Guar Gum ◽

Loss Modulus ◽

Industrial Applications ◽

Green Technology ◽

Low Molecular Weight ◽

Radiation Processing ◽

Industrial Sectors ◽

Wide Acceptance

Guar gum and its derivatives are highly important industrial hydrocolloids as they find applications in various industrial sectors. Guar is a polymer of high molecular weight and its aqueous solutions exhibit unique rheological properties, which has led to its wide acceptance by the industry. In certain industrial applications low molecular weight guar and its derivatives are needed, and conventionally chemical depolymerisation of guar is carried out for this purpose. Radiation processing is a novel and green technology for carrying out depolymerization and can be an ideal substitute for chemical depolymerisation technique. In order to study the effect of radiation on guar derivatives, three types of derivatives have been taken in the present study: carboxymethyl, hydroxyethyl, and methyl guar. The effect of 1–50 KGy radiation dose on the rheological behavior of these derivatives has been studied, and the results have been described in the present paper. The effect on storage and loss modulus with respect to frequency and effect on viscosity with respect to shear rate have been discussed in detail.

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Assessment of Fennel Oil Microfluidized Nanoemulsions Stabilization by Advanced Performance Xanthan Gum

Foods ◽

10.3390/foods10040693 ◽

2021 ◽

Vol 10 (4) ◽

pp. 693

Author(s):

Rubén Llinares ◽

Pablo Ramírez ◽

José Antonio Carmona ◽

Luis Alfonso Trujillo-Cayado ◽

José Muñoz

Keyword(s):

Essential Oil ◽

Rheological Properties ◽

Xanthan Gum ◽

Mechanical Energy ◽

Physical Stability ◽

Processing Condition ◽

Oil In Water ◽

Mechanical Spectra ◽

The Stability ◽

Fennel Oil

In this work, nanoemulsion-based delivery system was developed by encapsulation of fennel essential oil. A response surface methodology was used to study the influence of the processing conditions in order to obtain monomodal nanoemulsions of fennel essential oil using the microchannel homogenization technique. Results showed that it was possible to obtain nanoemulsions with very narrow monomodal distributions that were homogeneous over the whole observation period (three months) when the appropriate mechanical energy was supplied by microfluidization at 14 MPa and 12 passes. Once the optimal processing condition was established, nanoemulsions were formulated with advanced performance xanthan gum, which was used as both viscosity modifier and emulsion stabilizer. As a result, more desirable results with enhanced physical stability and rheological properties were obtained. From the study of mechanical spectra as a function of aging time, the stability of the nanoemulsions weak gels was confirmed. The mechanical spectra as a function of hydrocolloid concentration revealed that the rheological properties are marked by the biopolymer network and could be modulated depending on the amount of added gum. Therefore, this research supports the role of advanced performance xanthan gum as a stabilizer of microfluidized fennel oil-in-water nanoemulsions. In addition, the results of this research could be useful to design and formulate functional oil-in-water nanoemulsions with potential application in the food industry for the delivery of nutraceuticals and antimicrobials.

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Evaluations about the physico-chemical stability of docetaxel and irinotecan pre-diluted and diluted solutions: pharmaco-economic perspectives

Drugs and Therapy Studies ◽

10.4081/dts.2013.e6 ◽

2013 ◽

Vol 3 (1) ◽

pp. 6 ◽

Cited By ~ 1

Author(s):

Mariarita Laforgia ◽

Anna Elisa Quatrale ◽

Nicola A. Colabufo ◽

Amalia Azzariti ◽

Angelo Paradiso ◽

...

Keyword(s):

Chemical Stability ◽

Mobile Phase ◽

Ammonium Acetate ◽

Physical Stability ◽

Experimental Conditions ◽

Phase Gradient ◽

Methanol Mixture ◽

Physico Chemical ◽

Starting Point ◽

Economic Perspectives

Several clinically used anticancer drugs are well-known as far as their pharmacologic properties are concerned, but scarcely ever the interest towards their physico-chemical characteristics in solution led to practical acknowledgement in their management. Thanks to the Units for Centralized Anticancer Drug Handling, the importance to evaluate the concentration of saturation (physical stability) or the possible transformations undergone by a drug in solution (chemical stability) has become the starting point for avoiding useless wasting drugs and economic resources. By HPLC experiments we have demonstrated that the solutions of two drugs, docetaxel and irinotecan, are particularly stable at different concentrations and times of analyses in our experimental conditions. The best mobile phase for docetaxel was water/methanol/acetonitrile in 42/32/26 volumetric ratio: for halving concentrations (0.72-0.36-0.18-0.09 mg/mL) in NaCl 0.9%, the highest value gave a six-day and the three lower concentrations a fourteen-day stability, when storage occurred at room temperature and light protected. Elution of irinotecan was possible through an analysis in mobile phase gradient: at t0 a 20% ammonium acetate 10 mM and 80% methanol mixture, and after 5 min, a 80% ammonium acetate 10 mM and 20% methanol mixture. The physico-chemical stability was showed for five days, for any concentration of analysis when storage occurred at 2-8°C and light protected.

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