Comparative study on the digestion and absorption characteristics of n-3 LCPUFA-enriched phospholipids in the form of liposomes and emulsions

Engineering marine phospholipid nanoliposomes via glycerol-infused proliposomes: Mechanisms, strategies, and versatile applications in scalable food-grade nanoliposome production

This study presents a novel approach using polyol-based proliposome to produce marine phospholipids nanoliposomes. Proliposomes were formulated by blending glycerol with phospholipids across varying mass ratios (2:1 to 1:10) at room temperature. Analysis employing polarized light microscopy, FTIR, and DSC revealed that glycerol disrupted the stacked acyl groups within phospholipids, lowering the phase transition temperature (Tm). Krill oil phospholipids (KOP) proliposomes exhibited superior performance in nanoliposomes formation, with a mean diameter of 125.60 ± 3.97 nm, attributed to the decreased Tm (-7.64 and 7.00 °C) compared to soybean phospholipids, along with a correspondingly higher absolute zeta potential (-39.77 ± 1.18 mV). The resulting KOP proliposomes demonstrated liposomes formation stability over six months and under various environmental stresses (dilution, thermal, ionic strength, pH), coupled with in vitro absorption exceeding 90 %. This investigation elucidates the mechanism behind glycerol-formulated proliposomes and proposes innovative strategies for scalable, solvent-free nanoliposome production with implications for functional foods and pharmaceutical applications.

Mechanism of color change in Antarctic krill oil during storage

Antarctic krill oil (AKO) is reddish-orange in color but undergoes changes during storage. To investigate the color deterioration and potential mechanisms involved, the changes in color, endogenous components (astaxanthin, fatty acids, and phospholipids), and reaction products (aldehydes, α-dicarbonyl compounds, and pyrroles) of AKO upon storage were determined. Although the visual color of AKO tended to darken upon storage, the colorimetric analysis and ultraviolet-visible spectrum analysis both indicated a fading in red and yellow due to the oxidative degradation of astaxanthin. During storage of AKO, lipid oxidation led to the formation of carbonyl compounds such as aldehydes and α-dicarbonyls. In addition, phosphatidylethanolamines (PEs) exhibited a faster loss rate than phosphatidylcholines. Moreover, hydrophobic pyrroles, the Maillard-like reaction products associated with primary amine groups in PEs accumulated. Therefore, it is suggested that the Maillard-like reaction between PEs and carbonyl compounds formed by lipid oxidation contributed to color darkening of AKO during storage.

Carboxymethyl chitosan coated alpha-linolenic acid nanoliposomes: Preparation, stability and release in vitro and in vivo

Nanoliposome encapsulation combined with carboxymethyl chitosan (CMCS) surface decoration was employed to improve physicochemical stability and oral bioavailability of alpha-linolenic acid (ALA). Different nanoliposome systems including ALA-loaded nanoliposomes (ALA-NLs) and CMCS-coated ALA-NLs (CMCS-ALA-NLs) were characterized through dynamic light scattering, transmission electron microscope, Fourier transform infrared spectroscopy and differential scanning calorimetry. The results showed that CMCS-ALA-NLs had good encapsulation efficiency of 79% and layer formation with nanosized spherical carrier. The physicochemical stability of CMCS-ALA-NLs was better than that of ALA-NLs. CMCS-ALA-NLs were able to regulate the release of ALA in a simulated gastrointestinal environment. In vivo testing found that ALA concentration of CMCS-ALA-NLs had an area under the curve of 1.32, which was 1.28 times higher than that of ALA-NLs and 2 times higher than that of ALA-emulsion. The absorption of ALA was improved by CMCS-ALA-NLs. It suggested that CMCS-coated nanoliposomes should be an available delivery strategy for transporting ALA.

OSA-starch stabilized EPA nanoliposomes: preparation, characterization, stability and digestion in vitro and in vivo

OSA-starch stabilized EPA nanoliposomes (OSA-EPA-NLs) were prepared by thin film rehydration/dispersion method. The physical properties and morphology of OSA-EPA-NLs were characterized. The best formulated sample was used to measure the storage stability and oxidative properties of EPA under different environmental stresses and to determine release and absorption of OSA-EPA-NLs in vitro and in vivo. The results showed that the encapsulation efficiency of OSA-EPA-NLs was 84.61%. All samples were relatively stable under different environmental stresses, and the release rate of EPA in simulated intestine stage (89.87%) was higher than that in the simulated gastric stage (5.86%). The areas under the EPA concentration-time curve of OSA-EPA-NLs group and EPA-NLs group through in vivo study were 0.42 and 0.32, respectively, which indicated that OSA-starch could improve the stability of EPA nanoliposomes and enhance EPA bioavailability in the form of ethyl esters.

Physical and Oxidative Water-in-Oil Emulsion Stability by the Addition of Liposomes from Shrimp Waste Oil with Antioxidant and Anti-Inflammatory Properties

Liposomes made of partially purified phospholipids (PL) from Argentine red shrimp waste oil were loaded with two antioxidant lipid co-extracts (hexane-soluble, Hx and acetone-soluble, Ac) to provide a higher content of omega-3 fatty acids. The physical properties of the liposomes were characterized by Transmission Electron Microscopy (TEM), Dynamic Light Scattering (DLS) and Differential Scanning Calorimetry (DSC). The antioxidant and anti-inflammatory activity of the lipid extracts and liposomal suspensions were evaluated in terms of Superoxide and ABTS radical scavenging capacities and TNF-α inhibition. Uni-lamellar spherical liposomes (z-average ≈ 145 nm) with strong negative ζ potential (≈ -67 mV) were obtained in all cases. The high content of neutral lipids in the Hx extract caused structural changes in the bilayer membrane and decreased entrapment efficiency regarding astaxanthin and EPA + DHA contents. The liposomes loaded with the Hx/Ac extracts showed higher antioxidant and anti-inflammatory activity compared with empty liposomes. The liposomal dispersions improved the physical and oxidative stability of water-in-oil emulsions as compared with the PL extract, inducing pronounced close packing of water droplets. The liposomes decreased hydroperoxide formation in freshly made emulsions and prevented thio-barbituric acid-reactive substances (TBARS) accumulation during chilled storage. Liposomes from shrimp waste could be valuable nanocarriers and stabilizers in functional food emulsions.

Docosahexaenoic Acid Delivery Systems, Bioavailability, Functionality, and Applications: A Review

Docosahexaenoic acid (DHA), mainly found in microalgae and fish oil, is crucial for the growth and development of visual, neurological, and brain. In addition, DHA has been found to improve metabolic disorders associated with obesity and has anti-inflammatory, anti-obesity, and anti-adipogenesis effects. However, DHA applications in food are often limited due to its low water solubility, instability, and poor bioavailability. Therefore, delivery systems have been developed to enhance the remainder of DHA activity and increase DHA homeostasis and bioavailability. This review focused on the different DHA delivery systems and the in vitro and in vivo digestive characteristics. The research progress on cardiovascular diseases, diabetes, visual, neurological/brain, anti-obesity, anti-inflammatory, food applications, future trends, and the development potential of DHA delivery systems were also reviewed. DHA delivery systems could overcome the instability of DHA in gastrointestinal digestion, improve the bioavailability of DHA, and better play the role of its functionality.

Absorption, Pharmacokinetics, Tissue Distribution, and Excretion Profiles of Sea Cucumber-Derived Sulfated Sterols in Mice

Sea cucumber-derived sulfated sterols exhibited more significant bioactivities compared to plant sterols due to the distinctive structure of the sulfate group at the C-3 position; however, their absorption, pharmacokinetics, tissue distribution, and excretion profiles are unknown, which limits the analysis of molecular mechanisms related to their unique activities. In this study, the absorption characteristics of sea cucumber sterols were determined by oral gavage administration, and their pharmacokinetics, excretion, and tissue distribution were studied by tail vein injection. The results showed that SS1 and SS2 reached the peak at 3 h (20.14 ± 1.2 μg/mL) and 4 h (13.32 ± 0.9 μg/mL) in serum, respectively, after oral gavage administration, suggesting the faster absorption rate of SS1 than SS2 due to the difference in the side-chain groups. Besides, lipid-containing food media improved the digestion and absorption rates of sea cucumber sterols. Moreover, SS1 exhibited a relatively longer duration of efficacy than SS2, and they were almost completely excreted within 9 h through urine. Additionally, sea cucumber sterols were found to be mainly accumulated in the liver (P < 0.05), followed by the kidney and spleen. These findings might provide a theoretical basis for the research and development of functional foods and nutraceuticals associated with sea cucumber sterols.