Oxidatively stable curcumin‐loaded oleogels structured by β‐sitosterol and lecithin: physical characteristics and release behaviour in vitro

Abstract

Summary In this study, oleogel structured by β‐sitosterol and lecithin was prepared as a carrier for poorly water‐soluble bioactive compounds, curcumin. The mechanical and microscopic properties of curcumin‐loaded oleogel were determined by texture analyser and polarised light microscopy. The oxidation stability of the delivery system was determined by accelerated oxidation test and the bioaccessibility of curcumin was studied in vitro. The results showed that the existence of curcumin did not affect the mechanical strength and crystalline network of oleogel. The oxidative stability of curcumin‐loaded oleogel was higher than that of curcumin‐free oleogel and corn oil‐curcumin mixtures. It might be attributed to not only the antioxidative property of curcumin but also crystalline network of oleogel which served as an obstructor for the development of oxidation products. Additionally, oleogel enhanced the bioaccessibility of curcumin in fasted state (up to 67.66%). These findings suggest that oleogels can be promising candidates to delivery drugs and nutrients.

Determination of physical and chemical properties of oleogels prepared with olive oil and olive‐based emulsifier

“…Thus, this shows that increasing the amount of OBE reduced the sensitivity of olive oil to oxidation by affecting the saturation/ unsaturation changes in fatty acid. The same results were reported by (Lim, Jeong, et al (2017) for soybean oil-carnauba wax oleogels, Li et al (2019) for corn oil-curcumin-loaded oleogels, and Oh et al (2019) for canola oil-hydroxypropyl methylcellulose oleogels.…”

Effect of Adding Curcumin on the Properties of Linseed Oil Organogels Used as Fat Replacers in Pâtés

“…Similarly, Beddows et al [ 56 ] reported that curcumin had an antioxidant effect in sunflower oil heated at 105 °C, but it did not improve the preservation of α-tocopherol. The incorporation of curcumin in corn oil organogels based on β-sitosterol and lecithin increased the oxidative stability at 60 °C, measured by peroxide value and p -anisidine, compared to a curcumin-free organogel [ 23 ]. However, the degradation of curcumin was not addressed in that study.…”

“…Although an accelerated oxidation study of the organogels with and without curcumin was performed at 60 °C for comparative purposes with other studies, this storage temperature was above the melting temperature of the organogels ( Table 1 ). In this case, organogels had liquid-like viscous behavior similar to liquid oils, where both the oxygen diffusion coefficient and the movement of reactants increase, increasing the oxidation rate of the polyunsaturated fatty acids of linseed oil [ 23 , 57 ].…”

“…Curcumin has been incorporated in different liquid edible oils to successfully prevent lipid oxidation, such as fish oil [ 19 ], sunflower oil [ 20 , 21 ] and soybean oil [ 22 ]. In two recent studies, curcumin has also been incorporated to organogels based on corn oil and a mixture of olive, linseed and fish oil [ 12 , 23 ] to increase their oxidative stability. However, the possible influence of curcumin, not only on the oxidative stability, but also on the arrangement of the crystalline network as well as thermal and rheological properties should be elucidated.…”

Preparation of Protein Oleogels: Effect on Structure and Functionality

“…Examples of LMWOGs that have been shown to form oleogels are monoglycerides [10][11][12][13][14][15][16][17][18], natural waxes [17,[19][20][21][22][23], enzymatically synthesized wax esters [24], ceramides [25], hydroxylated fatty acids [26,27], lecithin [28,29], and oligopeptides [30]. Additionally, combinations of LMWOGs have been studied, such as fatty acids and fatty alcohols [31,32], oleic acid and sodium oleate [33], sorbitan tri-stearate, tocopherol, phytosterol, β-citosterol or ceramide in combination with lecithin [34][35][36][37][38], γ-oryzanol and β-sitosterol [39][40][41][42][43], monoglycerides and phytosterols [44], beeswax and β-carotene [45], wax and monoglycerides [46], and combinations of fully hydrogenated oil, candedilla wax and monoglycerides [47].…”