Babak Ghanbarzadeh; Sahra Bashiri; Hamed Hamishekar; Jalal Dehghan nia
Abstract
Introduction : The encapsulation of nutraceuticals in lipid based carriers, such as liposomes, can lead to increasing of bio-active ingredients bioavailability and controlled release, maintaining their stability in different environmental conditions and increasing solubility of hydrophobic active ingredients ...
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Introduction : The encapsulation of nutraceuticals in lipid based carriers, such as liposomes, can lead to increasing of bio-active ingredients bioavailability and controlled release, maintaining their stability in different environmental conditions and increasing solubility of hydrophobic active ingredients in aqueous conditions. Food grade liposomes are being increasingly used in food industry to delivery hydrophilic and hydrophobic components such as vitamin E and vitamin C, ascorbic asid, nutraceuticals, essential omega 3 fatty medium chain fatty acids-vitamine C, nisine, cartenoides, oleic acids, polyphenols include catechine, synamic acids.One of the hydrophobic nutrients with antioxidant and beneficial pro-vitamine property is beta-carotene, which its high hydrophobicity and sensitivity in different environmental conditions has limited using of it for foodstuff enrichment. In order to improve the characteristics of the lipid bilayer, cholesterol traditionally has been included in the lipid membrane. It is important in decreasing permeability and strengthening the membrane. People suffering from hyper-cholesterolaemia are encouraged to avoid foods containing cholesterol. Since the plant sterols are natural compounds found in plant cell membranes which help maintain the membrane integrity. Such as Gama oryzanol is combination of different of plant sterols that is used in the formulation of nanoliposomes in this study to improve the stability of bilayers. The principal aim of this study was to prepare beta-caroten encapsulated nano- liposome formulations as a mean to improve its aqueous dispensability and to study the effect of lecithin-phytosterol concentrations on the partical size, encapsulation efficiency (EE), zeta potential, turbibility of beta carotene loaded nano-liposomes to get the optimized formulation. Materials and methods: Preparing liposomes is being carried out using different methods one of which is a novel technique called is “Mozafari method” (based on heating method). This method is characterized by the absence of organic solvent for the solving of lipids.Non-toxicity of produced liposomes; rapid production and scalability are some of the advantages of Mozafari method over other methods of liposome production. In this study, the liposomal ingredients were added to a preheated (60 0C, 5 min) water, mixeture of beta-carotene, gamma oryzanol solution and glycerol (final concentration 3% v/v) were added. The mixtures volume increased by adding warm water until 50ml, the mixture was further heated 60 while stirring 1200 rpm for 50-60 min under nitrogen atmosphere.Results and discussion: Effect of different concentration of lecithin (20, 40, 75, 100, 150, 200 mg) on particle size and zeta potential of nano-liposomes with constant amount of beta carotene (4 mg) and gamma-oryzanol for different concentration of lecithin with ratio 1:14 w/w were evaluated. The Particle size of nano liposomes with different concentration of lecithin was obtained below 500nm andthe optimal concentration of lecithin was 100 mg that particle size was minimum (64-88 nm).The gamma-oryzanol is a natural phytostrol which is as stabilizer for liposome membrance and promoting agent of hardness of vesicles wall however, the particle size of liposomes were reduced especially in low concentration of lecithin. The using phytosterols (gamma oryzanol) for maintaining the stability of liposomal membranesystems caused to reducing of particle size from 88nm to 64nm in 200 mg concentration of lecithin.The entrapment efficiency increased by increasing concentration of lecithin for nano-liposomes. It is because increasing the lecithin concentration, more vesicles were produced which in turn increased the loading capacity of nano-liposomes. In the liposome structure, the aqueous core and bilayer are the hydrophilic and hydrophobic parts, respectively. Therefore, the phospholipid bilayers place for beta carotene, and other hydrophobic substances. The entrapment efficiency in different concentration of lecithin was between 27-98%. The entrapment efficiency of liposomes containing beta carotene that used gamma oryzanol was less than liposomes without gamma oryzanol probably because the position of capsulation of gamma oryzanol and beta carotene is same in the bilayer of liposome that’s hydrophobic source of liposomes. But Gamma oryzanol was not effective on encapsulation efficiency of beta-carotene.The zeta potential, the electric potential in the interface or particle surface charge, is used to predict the stability of colloidal systems. In general, higher zeta potential values, regardless of their positive or negativity, indicate a higher and longer-term stability of the particles. Zeta potential of liposomes, which is a measure for the electrostatic repulsion and stability, was -29 and -35 milivolt for samples with and with not containing gamma oryzanol, respectively.For turbidity of liposomes, encapsulation of bioactive compounds can change the optical appearance due to the fact that the refractive index at the interface between solvent and internal phase changes and the size of liposomes may be altered. Increasing significantly of turbidity of liposomes (16% -80%), the wave length increase from 0.116 to 0.585 cm-1 high concentration of lecithin maybe due to increasing visuals and hydrophobic interactions.
Babak Ghanbarzadeh; Akram Pezeshki; Hamed Hamishekar; Mohammad Moghaddam
Abstract
Introduction: The encapsulation of hydrophobic nutraceutical compounds such as fat soluble vitamins in nanoliposomes is a potentially effective way to protect them from from light, oxygen and chemical degradation during the maintenance. One of the potential benefits of liposomal structures is encapsulation ...
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Introduction: The encapsulation of hydrophobic nutraceutical compounds such as fat soluble vitamins in nanoliposomes is a potentially effective way to protect them from from light, oxygen and chemical degradation during the maintenance. One of the potential benefits of liposomal structures is encapsulation of three water-soluble, fat-soluble and amphiphilic compounds and use of natural food ingredients such as lecithin with beneficial effects, in their production. In this study, the effect of lecithin-cholesterol concentrations on particle size, particle size distribution, encapsulation efficiency (EE) and physical stability of vitamin A palmitate loaded nanoliposome during the storage time were explored to get the optimized formulationMaterials and method:Materials: Phospholipid (L-α-granular Lecithin) with purity of 99% was obtained from Across (USA). Cholesterol with 95% purity was supplied by Merck (Germany). Other chemicals were analytical grade and procured from Sigma (Merck Chemical Co. Darmstadt, Germany).Methods:Nanoliposomes were prepared from different concentrations of lecithin–cholesterol (60:0, 50:10, 40:20 and 30:30 mg) by thin-film hydration–sonication method. Lecithin and cholesterol were dissolved in absolute ethanol and then dried with vacuum evaporator. Prepared dried lipid film hydrated by aqueous phase. The resultant suspension was mixed for some time (Hydration-dehydration). Due to existence of water inside the lipid film, osmotic pressure runs the water into bilayer membrane and causes separation of lipid film and then liposomes were produced. In this method, mixture of Multilamellar Vesicles (MLVs) and Small Unilamellar Vesicles (SUVs) liposomes were produced. Reduction in particle sizes of prepared liposomes was done by ultra sound probe sonicator. The average diameter and span value of the particles were determined using particle size analyzer (Wing SALD 2101, Shimadzo, Japan), at 25°C and was calculated according to the DeBroukere mean in the Equation (1):The span value is an index helpful to evaluate the particle size distribution and calculated applying the following Equation: Morphology of the nano-carriers was observed using trans- mission electron microscopy (Zeiss-Leo 906 TEM (Germany). To determine the zeta potential of nano liposomes loaded vitamin A, Zeta siyzer device (Nano-ZS -Malvern England) was used at 25◦C temperature. Estimation of encapsulated vitamin in nanoliposomes (%EE) was carried out using HPLC (Knauer,Germany) equipped with a UV detector, C-18(10 mm 25mm_4.6 mm) column and acetonitrile– methanol (70:30%,v/v) as mobile phase and was calculated using the below equation%EE= (Encapsulated Vitamin A)/(Total Vitamin A) ×100The stability of vitaminA loaded-nanoliposomes was assessed by determining the average particle size at 4 °C over storage time and studying the leak out of the vitamin from the nanoliposomes after one month(1,7, 15and 30days)of storage at 4 °C by the below equation%Stability = (Remained Vitamin A)/(Initial encapsulated Vitamin A) ×100Results and Discussion: Results showed use of sonication in completion thin-film hydration method, induced production of monomodular nanoliposomes with uniform distribution The particle size was in the range of 76-115nm and particle size distribution was monomodular (span= 0.6- 0.88). In agreement with particle size results, TEM image showed that the vesicles are in the form of small unilamellar vesicles by bilayer nature. In all concentrations of lecithin-cholesterol, obtained EE was low and by increasing the lecithin concentration, loading capacity of nano liposomes increased. By increasing the lecithin concentration, more vesicles are produced which causes increase in internal volume of liposomes and bio actives concentrate, consequently loading capacity of nano liposomes increased. By tightening of the membrane by cholesterol, entrapment efficiency of hydrophobic active compounds such as vitamin A palmitate reduces. Also probably existence of cholesterol in liposome membrane inhibits of rupture and changes in liposome membrane. Overall, increasing the ratio of cholesterol /lecithin had no significant effect on particle size but decreased encapsulation efficiency of vitamin A palmitate to 10.23%. Addition of cholesterol effected on stability of the particle size of nanoliposomes and also led to reduction encapsulation efficiency of vitamin A palmitate. Incorporation of cholesterol and vitamin A palmitate into the liposome structure was increased the zeta potential from -29 to -58 mv and improved electrostatic stability. 50-10 mg ratio of lecithin-cholesterol concentration was used for preparation of optimum formulation of nanoliposome by monomodular and small size distribution (76 nm, span=0.74) and encapsulation efficiency (15.8%). Stability of vitamin A in nano liposome with 50-10 mg lecithin-cholesterol, was almost low (32% reduction during storage time), may be due to increasing fluidity of membrane. Permeability of vitamin A into phospholipid chains causes reorientation of acyl chains which leads to fluidity of membrane and exit active compound from nano carrier and more its hydrolytic degradation and oxidation. While the use of thin film hydration method using ultrasonic waves, is successful way in producing nanoscale particles of vitamin A palmitate nanoliposomes that are stable and decrease over time, but due to low efficiency and low sustainability of encapsulation, use of other nanocarriers for encapsulating of vitamin A palmitate is recommended
Zahra Mohammad Hassani; Babak Ghanbarzadeh; Hamed Hamishekar; Reza Rezaeemokaram
Abstract
Utilization of non-food-grade organic solvents and high shear forces in conventional liposome formation techniques has limited their applications as carriers of nutrecuticals in food industry. The objective of this research is the production of gamma-oryzanol bearing nanoliposome by using modified thermal ...
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Utilization of non-food-grade organic solvents and high shear forces in conventional liposome formation techniques has limited their applications as carriers of nutrecuticals in food industry. The objective of this research is the production of gamma-oryzanol bearing nanoliposome by using modified thermal method. Nanoliposomes were produced by a suitable concentration of lecithin and gamma-oryzanol solution. Size and zetapotential of nanoliposomes was determined using laser light scattering method and Infrared spectroscopy (FTIR) was employed for detection of interaction type between the nanoliposome and gamma-oryzanol. Then, the prepared samples were tested in terms of turbidity, stability, and rheological properties. The FTIR results demonstrate that interactions between lecithin and gama-oryzanol are weak physical type. The results of particle size showed that size distribution (span) were in the range of 90-110 nm and 0.69- 0.90, respectively. The negative zeta potential and loading capacity were reported 20.4 mV and 15.7% (±0.07), respectively. The results indicated that the prepared samples were stable in the 4 ˚C temperature. Increase of lecithin concentration increased turbidity. It was observed that the viscosity not changed by increasing the shear rate (Newtonian behavior), suggesting a nonflocculated system with very small particle size pointing toward the stability of the system.
Sajedeh Bahrani; Babak Ghanbarzadeh; Hamed Hamishekar; Mahood Sowti Khiabani
Abstract
Encapsulation of bioactive ingredient and production of nano carriers in order to food enrichment and production of functional food is one of the applications of nano technology in food science and pharmaceutical. Nano carriers are produced using biopolymers (proteins and polysaccharids) or lipid based ...
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Encapsulation of bioactive ingredient and production of nano carriers in order to food enrichment and production of functional food is one of the applications of nano technology in food science and pharmaceutical. Nano carriers are produced using biopolymers (proteins and polysaccharids) or lipid based materials. In this research, production and characterization of pectin-casein nanocomplexes as a potential nanocarrier were investigated by Fourier Transform Infrared Spectroscopy (FTIR) and measurement of particle size and distribution. FTIR results showed electrostatic interactions between pectin and casein. Transmission Electron Microscopy, zeta potential and particle size showed stable dispersion with 86 nm at pH = 1.4, casein %1 and pectin 0.45. Nanocomplex solutions compared to pure pectin and sodium caseinate solutions have higher shear stress and viscosity in constant shear rate and rheological behavior of biopolymer solutions were altered from Newtonian to non Newtonian in complexes includes casein and pectin.
