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Solid lipid nanoparticles (SLN) are one of the appropriate delivery systems which are attracted enormous interest for encapsulating bioactive componds in recent years. One of the important physicochemical properties of SLNs is particle size that is influenced by formulation and production process parameters. Inappropriate conditions of the nanaocarrier production process in the pre and main emulsion steps cause unsuitable paricle size as well as unstable emulsion and gel formation. Therefore, in this research production process of SLN was investigated and optimized by hot homogenization method and with two lipids of Compritol and Precirol separately. Hence, homogenization time in preparation of pre emulsion and amplitude and time of ultrasonication in final emulsion production was studied to obtained the smallest particle size. In pre emulsion step, the smallest particle size for Compritol SLN (619±4 nm) and Precirol SLN (373±3 nm) obtained in 180 second mixing by ultra-turax in 16000 (rpm). In final emulsion, 40% amplitude and 3 minutes caused to attained smallest particle size in Compritol SLN (397±5 nm) and Precirol SLN (259±2 nm). Then polydispersity index (PDI), zeta potential and visual observation of nanocarriers with optimized particle size were examined. The results showed that Precirol SLN had higher zata potential (-12.3±0.6 mV) than Compritol SLN (-8.97±0.17mV) but PDI of two nanocarriers was not significantly different. Visual observation of both nanocarriers at the storage time showed no instability. [ABSTRACT FROM AUTHOR]

Oxidation of lipids in food is one of the most important factors in food degradation during processing, storage and distribution through adverse effects on aroma, color, nutritional value and also the production of toxic compounds. In this regard, this study was conducted to investigate the antioxidant effects of free grape pomace extract and nanoliposomes containing it on some oxidation parameters of soybean oil. In this study, 5 concentrations of nanoliposomes containing grape pomace extract (50, 100, 200, 500 and 1000 ppm), one level (200 ppm) of synthetic antioxidant (BHT) and one concentration (500 ppm) of free grape pomace extract were used and tests such as Acidity, peroxide, thiobarbituric acid index, conjugate diene, oxidative stability and refractive index of oils were stored in a laboratory oven at 63 ° C for 7 days. The results showed that with increasing the concentration of nanoliposomes containing antioxidants of grape pomace extract up to 500 ppm, the increase in acidity, thiobarbituric acid index, peroxide, conjugated diene and refractive index was less intense, but at higher concentrations of nanoliposomes used in this oil, Increased more. On the other hand, it was found that with increasing storage time, the amount of acidity, thiobarbituric acid, conjugated diene increased, but the amount of peroxide and refractive index of oils increased until the fifth day and then decreased. The results also showed that the highest oxidative stability of oils (7.6 h) was related to the sample containing 500 ppm nanoliposomes containing antioxidant extract of grape pomace. Finally, it can be said that the use of nanoliposomes containing grape pomace antioxidant extract is a good alternative to synthetic antioxidants on the market. [ABSTRACT FROM AUTHOR]

Curcumin (diferuloylmethane), a polyphenol extracted from Curcuma longa, has been well known for its functional properties. In this study, nanostructured lipid carrier (NLC) and solid lipid nanoparticles (SLN) were used to encapsulate curcumin, overcoming its limitations in food application, such as instability, poor bioavailability and poor aqueous solubility. Nanocarriers were produced by a combination of high shear homogenization and ultrasonication methods. Effect of lipids ratio, type of nanocarriers and curcumin loading on some physicochemical properties of the nanocarriers were studied. Considering both bulky structure of curcumin and increase dviscosity of dispersed phase in the presence of the active ingredient, incorporatingthe curcumin into the nanocarriers led to a significant increase in particle size and PDI. Statistical analysis showed that lipid ratio, nano-carrier type (SLN and NLC) and curcumin loading had a significant effect on particle size (p <0.05). Based on DSC results, curcumin was well encapsulated by nanocarriers without interactions with other ingredients. Generally, the concentration of 0.05%glycerol distarate and 0.25%curcumin were optimal conditions for NLC nanocarrier production. [ABSTRACT FROM AUTHOR]