Oxidative Stability of Polyunsaturated Edible Oils Mixed With Microcrystalline Cellulose

Changes in the quality of flaxseed oil powder produced by incorporating with microcrystalline cellulose and thyme

Flaxseed oil is a high nutrition oil, rich in ω-3 fatty acid, tocopherols and phenolic compounds. However, it is prone to oxidation due to its high unsaturation which needs pretreatments to be easily introduce to the market. In this study, flaxseed oil was converted to powder form by mixing with microcrystalline cellulose (MC) and thyme powder to produce flaxseed oil powder. For this purpose, 3 different levels of thyme powder (5%, 10% and 15% of oil) were mixed with oil, followed by mixing with different proportions of MC (50:50, 50:75, 50:100 (oil:MC)) and stored for 90 days at 25 °C and 4 °C. Results indicated that the total phenolic compounds (23.2-91.2 mg GAE/100 g), chlorophyll (9-63.6 mg/kg), and carotenoid (4.4-9.9 mg/kg) contents increased with the incorporation of thyme powder into the flaxseed oil on the first day in 25 °C and 4 °C. Also during 90 days storage, phenolic compound (21.8%), chlorophyll (32.5%) and carotenoid (24%) decreased in both 25 °C and 4 °C temperatures. The results confirmed that adding thyme powder to samples decreased acidity and peroxide value in compare with control. Using thyme as a natural antioxidant and also transforming the oil to powder form by MC increased the oxidative stability in compare with control. The produced high stable flaxseed oil powder has the potential to be used directly on food products like salads or to be used in different food formulations to fortify them with natural antioxidants and ω-3 essential fatty acids.

Derivatizing l-histidine to develop a novel additive for a polyol-based biolubricant

A novel histidine Schiff base ester, HSE-A, with excellent solubility in a polyol was used as a multifunctional additive for biolubricants.

Formulation, characterization and optimization of liposomes containing eicosapentaenoic and docosahexaenoic acids; a methodology approach

Omega-3 fatty acids (FAs) have been shown to prevent cardiovascular disease. The most commonly used omega-3 fatty acids like eicosapentaenoic acid (EPA) and docosahexaenoic acid (DHA) are highly vulnerable to oxidation and therefore, have short shelf life. Recent advances in nanoliposomes provided a biocompatible system for stabilizing omega-3 FAs. Several methods could be implemented to prepare nanoliposomes. To the best of our knowledge, the performances of these methods in preparation omega-3 FAs have not been examined. Nanoliposomes were prepared by thin film hydration followed by one of the following methods: 1- extrusion, ultrasonic irradiation; 2- bath sonication; 3- probe sonication; or 4- combined probe and bath sonication. The size of liposomes obtained from methods 1 to 4 were 99.7 ± 3.5, 381.2 ± 7.8, 90.1 ± 2.3, and 87.1 ± 4.10 nm with zeta potential being -42.4 ± 1.7, -36.3 ± 1.6, -43.8 ± 2.4, and 31.6 ± 1.9 mV, respectively. The encapsulation efficiency (EE) for DHA was 13.2 ± 1.1%, 26.7 ± 1.9%, 56.9 ± 5.2% and 51.8 ± 3.8% for methods 1 to 4, respectively. The corresponding levels for EPA were 6.5 ± 1.3%, 18.1 ± 2.3%, 38.6 ± 1.8%, and 38 ± 3.7%, respectively. The EE for DHA and EPA of liposomes for both methods 3 and 4 increased significantly (p<0.05). Propanal, as the major volatile product formed during liposomal preparations, amounts from 81.2 ± 4.1 to 118.8 ± 2.3 μg/Kg. The differential scanning calorimetry (DSC) study showed that DHA and EPA influence the phase transition temperature of small unilamellar vesicles (SUVs) of dipalmitoyl phosphatidyl choline (DPPC). Transmission electron microscopy (TEM) images of liposomes stained with uranyl acetate showed that the liposomes were spherical in shape and maintain high structural integrity. In conclusion, probe ultrasound of pre-formed liposomes facilitates significant loading of DHA and EPA into the nanoliposomal membrane.