Development of Innovative Lipid-based Materials for Encapsulation of Bioactive Ingredients

This report is based on studies that were aimed at developing innovative emulsifiers for use in emulsion-based systems, which can deliver omega-3 rich oils into food products. The emulsifiers have been designed to have antioxidant properties, which can provide increased oxidative stability to the emulsified oil. The synthesis of the emulsifiers has been based on the use of saccharides originating from alginate; a cheap and abundant marine polysaccharide. The strategy has been to enzymatically depolymerize alginate, followed by modification of the alginate saccharides with hydrophobic moieties. In this study, the alginate saccharides have been characterized, and it has been found, that these saccharides have excellent antioxidative properties, making them good starting materials for the development of the desired emulsifiers. Work is ongoing to modify the alginate saccharides for the production of emulsifiers, which will be applied in the formation of oil-in-water emulsions. These emulsions will be characterized, with special focus on their physical stability and the oxidative stability of the emulsified oil

Production and concentration of monoacylglycerols rich in omega-3 polyunsaturated fatty acids by enzymatic glycerolysis and molecular distillation

Production of monoacylglycerols (MAGs) rich in x-3 polyunsaturated fatty acids (n-3 PUFAs) was conducted through short path distillation (SPD) of an acylglycerol mixture (containing 67% MAGs) produced by enzymatic glycerolysis of sardine oil with glycerol. A stepwise SPD process in a UIC KDL 5 system (vacuum 10 3 mbar, feeding flow 1.0 mL/min) was proceeded: the first distillation performed at evaporator temperature (TE) of 110 C to remove glycerol completely and most of FFAs; and the second distillation at optimized TE 155 C; resulting in a stream distillate with 91% purity and 94% overall recovery of MAGs. This work also demonstrated that SPD is able to concentrate n-3 PUFAs in MAG form by distilling at proper TE e.g. 125 C, where n-3 PUFAs are concentrated in the residues. Moreover, this work mapped out a complete processing diagram for scalable production of n-3 PUFAs enriched MAGs as potential food emulsifier and ingredient.Spanish Government through MINECO and the European Regional Development Fund (ERDF) for financial support to the project CTQ2012-39131-C02-01

Ionic Liquids in the Synthesis of Antioxidant Targeted Compounds

Oxidation of polyunsaturated lipids is a major cause of degradation of the sensory and nutritional quality of food products. The oxidation reactions lead to formation of volatile compounds generally associated with unpleasant flavors, which damages the sensory quality of foods. Lipid oxidation is also responsible for a loss of macro- and micronutrients, and leads to the formation of potentially toxic compounds.The interest in using antioxidants from natural sources is increasing, and ionic liquids (ILs) have attracted considerable attention as solvents in extraction and separation of antioxidants from natural materials. Additionally, ILs are also applied as reaction media for the lipophilization of natural antioxidant. Lipophilization of antioxidants improve the oil solubility and tailor the antioxidants to specific applications, according to the polar paradox and cutoff theorie

Facile synthesis of phosphatidyl saccharides for preparation of anionic nanoliposomes with enhanced stability.

Physical stability during storage and against processing such as dehyration/rehydration are the cornerstone in designing delivery vehicles. In this work, mono-, di- and tri-saccharides were enzymatically conjugated to phosphatidyl group through a facile approach namely phospholipase D (PLD) mediated transphosphatidylation in a biphasic reaction system. The purified products were structurally identified and the connectivities of carbohydrate to phosphatidyl moiety precisely mapped by (1)H, (31)P, (13)C NMR pulse sequences and LC-ESI-FTMS. The synthetic phosphatidyl saccharides were employed as the sole biomimetic component for preparation of nanoliposomes. It was found that the critical micelle concentration (CMC) of phosphatidyl saccharides increases as more bulky sugar moiety (mono- to tri-) is introduced. Phosphatidyl di-saccharide had the largest membrane curvature. In comparison to the zwitterionic phosphatidylcholine liposome, all phosphatidyl saccharides liposomes are anionic and demonstrated significantly enhanced stability during storage. According to the confocal laser scan microscopy (CLSM) and atom force microscopy (AFM) analyses, the nanoliposomes formed by the synthetic phosphatidyl saccharides also show excellent stability against dehydration/rehydration process in which most of the liposomal structures remained intact. The abundance hydroxyl groups in the saccharide moieties might provide sufficient H-bondings for stabilization. This work demonstrated the synthesized phosphatidyl saccharides are capable of functioning as enzymatically liable materials which can form stable nanoliposomes without addition of stabilizing excipients

Characterization of nanoliposomes of PC, Ptd-Glu, Ptd-Suc and Ptd-Raff following prolonged storage by CLSM and DLS.

<p>(a-d) Morphology of freshly prepared nanoliposomes (size bar: 5 µm). (e-h) Morphology of nanoliposomes following storage for 14 days at room temperature (size bar: 5 µm). (i-l) Size dispersion of freshly prepared nanoliposomes and nanoliposomes stored for 14 days.</p

AFM topographic images of the nanoliposomes of PC (a), Ptd-Glu (b), Ptd-Suc (c) and Ptd-Raff (d) on mica surface following dehydration procedure.

<p>The height distribution of these structures were depicted in (e).</p

Physical stability of PC and phsphatidyl saccharide nanoliposomes following prolonged storage: a) freshly prepared nanoliposomes, b) nanoliposome after storage for 14 days at room temperature.

<p>Physical stability of PC and phsphatidyl saccharide nanoliposomes following prolonged storage: a) freshly prepared nanoliposomes, b) nanoliposome after storage for 14 days at room temperature.</p

Critical micelle concentration (CMC), liposome average size and zeta potential of PC, Ptd-Glu, Ptd-Suc and Ptd-Raff.

<p>Critical micelle concentration (CMC), liposome average size and zeta potential of PC, Ptd-Glu, Ptd-Suc and Ptd-Raff.</p

Phosphatidyl saccharides and the mechanism concerning stabilization of phosphatidyl saccharides nanoliposomes during storage and dehydration/rehydration.

<p>(a) Structure of enzymatic synthesized phosphatidyl saccharides (1:Ptd-Glu; 2:Ptd-Suc; 3:Ptd-Raff). (b) Both the electrostatic repulsive force caused by negative surface charge and the enhanced hydrogen bond between saccharide head groups contributed to the improved stability of phosphatidyl saccharides nanoliposomes.</p