Influence of O/W emulsion interfacial ionic membranes on the encapsulation efficiency and storage stability of powder microencapsulated astaxanthin

Emulsification and stabilisation technologies used for the inclusion of lipophilic functional ingredients in food systems

Food industry is increasingly using functional ingredients to improve the food product quality. Lipid-containing functional ingredients are important sources of nutrients. This review examines the current state of emulsification and stabilisation technologies for incorporating lipophilic functional ingredients into food systems. Lipophilic functional ingredients, such as omega-3 fatty acids, carotenoids, and fat-soluble vitamins, offer numerous health benefits but present challenges due to their limited solubility in water-based food matrices. Emulsification techniques enable the dispersion of these ingredients in aqueous environments, facilitating their inclusion in a variety of food products. This review highlights recent advances in food emulsion formulation, emulsification methods and stabilisation techniques which, together, improve the stability and bioavailability of lipophilic compounds. The role of various emulsifiers, stabilizers, and encapsulation materials in enhancing the functionality of these ingredients is also explored. Furthermore, the review discusses different stabilisation techniques which can yield in emulsion in a solid or liquid state. By providing a comprehensive overview of current technologies, this review aims to guide future research and application in the development of functional foods enriched with lipophilic ingredients.

Recent Advances in the Therapeutic Potential of Carotenoids in Preventing and Managing Metabolic Disorders

Carotenoids constitute compounds of significant biological interest due to their multiple biological activities, such as antimicrobial, anticancer, antiadipogenic, antidiabetic, and antioxidant properties. Metabolic syndrome (MetS) comprehends a series of metabolic abnormalities (e.g., hypertension, obesity, and atherogenic dyslipidemia) that can affect children, adolescents, and the elderly. The treatment of MetS involves numerous medications, which, despite their efficacy, pose challenges due to prolonged use, high costs, and various side effects. Carotenoids and their derivatives have been proposed as alternative treatments to MetS because they reduce serum triglyceride concentrations, promote insulin response, inhibit adipogenesis, and downregulate angiotensin-converting enzyme activity. However, carotenoids are notably sensitive to pH, light exposure, and temperature. This review addresses the activity of carotenoids such as lycopene, lutein, fucoxanthin, astaxanthin, crocin, and β-carotene towards MetS. It includes a discussion of sources, extraction methods, and characterization techniques for analyzing carotenoids. Encapsulation approaches are critically reviewed as alternatives to prevent degradation and improve the biological performance of carotenoids. A brief overview of the physiopathology and epidemiology of the diseases, including MetS, is also provided.

Comparison of milk protein concentrate, micellar casein, and whey protein isolate in loading astaxanthin after the treatment of ultrasound-assisted pH shifting

Milk proteins can be used as encapsulation walls to increase the bioavailability of active compounds because they can bind hydrophobic, hydrophilic, and charged compounds. The objective of this study was to investigate the effects of astaxanthin (ASTA) encapsulation and the functional properties of milk protein and ASTA nanocomposites by an ultrasound-assisted pH-shifting treatment of different milk proteins, including milk protein concentrate (MPC), micellar casein (MCC), and whey protein isolate (WPI). The ultrasound-assisted pH-shifting treatment of milk protein helped to improve the encapsulation rate of ASTA. Therein, MCC showed great improvement of encapsulating ASTA after co-treatment with the raised encapsulated rate of 5.11%, followed by WPI and MPC. Furthermore, the nanocomposites of ASTA with milk protein exhibit improved bioavailability, antioxidant capacity, and storage stability. By comparison, MCC-encapsulated ASTA has the best storage stability, followed by MPC, and WPI-encapsulated ASTA has the least stability over a 28-d storage period. The results of intrinsic fluorescence and surface hydrophobicity showed that milk protein underwent fluorescence quenching after binding to ASTA, which was due to the hydrophobic sites of the protein being occupied by ASTA. In general, the nanocomposites of milk protein and ASTA fabricated by using an ultrasound-assisted pH-shifting treatment have the potential to be better nano-delivery systems for ASTA in functional foods, especially MCC, which showed excellent performance in encapsulation after treatment technique.

Preparation and in vitro characterization studies of astaxanthin-loaded nanostructured lipid carriers with antioxidant properties

The purpose of this study was to evaluate the astaxanthin-loaded nanostructured lipid carriers (ASX-NLC) prepared using a high-pressure homogenization transport system for local application of astaxanthin. Dynamic light scattering (DLS) and X-ray diffraction (XRD) were used to study the effect of microencapsulation on the properties of ASX-NLC. The mean size of ASX-NLC was about 108.43 ± 0.26 nm and PdI was 0.176 ± 0.002. The ASX-NLC had high encapsulation efficiency which was 95.69 ± 0.13%. Good light stability and temperature stability were shown at the ASX-NLC, indicating that the preparation process was feasible. The 2,2-diphenyl-1-pyridylohydrazinyl (DPPH) scavenging test showed that ASX-NLC could still play an antioxidant role. In vitro release studies showed that compared with an astaxanthin ethanol solution, an ASX-NLC could maintain astaxanthin release more effectively. In vitro permeation studies showed that ASX-NLC could increase astaxanthin retention in the skin. In conclusion, ASX-NLC could significantly enhance astaxanthin accumulation during dermal applications. The research results have important reference significance for local skin applications and provide a basis for the development of nanostructured lipid carriers. ASX-NLC might be suitable carriers for the local application of astaxanthin.

Simple Method for the Creation of a Bacteria-Sized Unilamellar Liposome with Different Proteins Localized to the Respective Sides of the Membrane

Artificial cells are membrane vesicles mimicking cellular functions. To date, giant unilamellar vesicles made from a single lipid membrane with a diameter of 10 μm or more have been used to create artificial cells. However, the creation of artificial cells that mimic the membrane structure and size of bacteria has been limited due to technical restrictions of conventional liposome preparation methods. Here, we created bacteria-sized large unilamellar vesicles (LUVs) with proteins localized asymmetrically to the lipid bilayer. Liposomes containing benzylguanine-modified phospholipids were prepared by combining the conventional water-in-oil emulsion method and the extruder method, and green fluorescent protein fused with SNAP-tag was localized to the inner leaflet of the lipid bilayer. Biotinylated lipid molecules were then inserted externally, and the outer leaflet was modified with streptavidin. The resulting liposomes had a size distribution in the range of 500-2000 nm with a peak at 841 nm (the coefficient of variation was 10.3%), which was similar to that of spherical bacterial cells. Fluorescence microscopy, quantitative evaluation using flow cytometry, and western blotting proved the intended localization of different proteins on the lipid membrane. Cryogenic electron microscopy and quantitative evaluation by α-hemolysin insertion revealed that most of the created liposomes were unilamellar. Our simple method for the preparation of bacteria-sized LUVs with asymmetrically localized proteins will contribute to the creation of artificial bacterial cells for investigating functions and the significance of their surface structure and size.

Recent Developments in the Microencapsulation of Fish Oil and Natural Extracts: Procedure, Quality Evaluation and Food Enrichment

Due to the beneficial health effects of omega-3 fatty acids and antioxidants and their limited stability in response to environmental and processing factors, there is an increasing interest in microencapsulating them to improve their stability. However, despite recent developments in the field, no specific review focusing on these topics has been published in the last few years. This work aimed to review the most recent developments in the microencapsulation of fish oil and natural antioxidant compounds. The impact of the wall material and the procedures on the quality of the microencapsulates were preferably evaluated, while their addition to foods has only been studied in a few works. The homogenization technique, the wall-material ratio and the microencapsulation technique were also extensively studied. Microcapsules were mainly analyzed for size, microencapsulation efficiency, morphology and moisture, while in vitro digestion, flowing properties, yield percentage and Fourier transform infrared spectroscopy (FTIR) were used more sparingly. Findings highlighted the importance of optimizing the most influential variables of the microencapsulation procedure. Further studies should focus on extending the range of analytical techniques upon which the optimization of microcapsules is based and on addressing the consequences of the addition of microcapsules to food products.

Preparation of soybean dreg fiber solid emulsifier and its effect on the stability of Pickering emulsion

High purity insoluble dietary fiber (HPIDF) was extracted from Okara by compound enzyme method, and solid emulsifiers with different particle sizes were prepared by wet grinding. Its composition, structure and physicochemical properties were studied, and the influence mechanism of solid emulsifiers with different particle sizes on emulsifying properties and interface stability of Pickering emulsion was systematically studied. The results showed that the particle size of HPIDF decreased significantly, the ζ-potential, contact Angle and swelling capacity of HPIDF ncrease significantly (p < 0.05). HPIDF forms an adsorption layer at the oil-water interface, and some of them are connected to form a bridge network structure, which plays a role of steric hindrance. And the emulsion has excellent stability under different environmental factors. HPIDF are suitable raw materials as natural food-grade solid emulsifiers. It is cost-effective and eco-friendly to realize the high-value utilization of Okara resources, reduce resource waste, and extend the industrial chain.

Improved intestinal absorption and oral bioavailability of astaxanthin using poly (ethylene glycol)-graft-chitosan nanoparticles: preparation, in vitro evaluation, and pharmacokinetics in rats

BACKGROUND

Astaxanthin (ASTA) is a kind of food-derived active ingredient (FDAI) with antioxidant and antidiabetic functions. It is nontoxic but its poor solubility and low bioavailability hinder its application in the food industry. In this study, a novel carrier, polyethylene glycol-grafted chitosan (PEG-g-CS) was applied to enhance the bioavailability of astaxanthin. It encapsulated astaxanthin completely by solvent evaporation to manufacture astaxanthin using poly (ethylene glycol)-graft-chitosan nanoparticles (ASTA-PEG-g-CS) nanoparticles to improve absorption.

RESULTS

The ASTA-PEG-g-CS nanoparticles were spherical, with a particle size below 200 nm and a ζ potential of about -26 mV. Polyethylene glycol-grafted chitosan can encapsulate astaxanthin well, and the encapsulated astaxanthin was released rapidly - in 15 min in an in vitro release study. In a rat single-pass intestinal perfusion study, a low concentration of ASTA-PEG-g-CS nanoparticle (0.2 μg mL^-1 ) was better absorbed in the intestine. In particular, the jejunum could absorb most astaxanthin without a change in the concentration. An in vivo release study also demonstrated that ASTA-PEG-g-CS nanoparticles enhanced oral bioavailability significantly.

CONCLUSION

This novel carrier, PEG-g-CS, provided a simple way to encapsulate food, which improved the bioavailability of hydrophobic ingredients. © 2021 Society of Chemical Industry.

Recent research advances in astaxanthin delivery systems: Fabrication technologies, comparisons and applications

Astaxanthin (AST) is classified as a kind of carotenoid with bright red color, powerful antioxidant activity as well as a range of health benefits. AST-based functional foods present a new thought of healthy diets with both the enhancement of food color and incorporation of nutrients. However, the poor water solubility, easy oxidation, light instability, thermal instability and peculiar smell excessively restrict its application in the food industry. In this review, common bio-based materials for various AST delivery systems suitable for different food products are highlighted. Moreover, characteristics of different delivery systems and current applications in food products are also compared and summarized. This review provides some ideas on the research trends and applications of AST delivery systems in food. The joint use of two or more materials can significantly enhance the stability of delivery systems. All of the encapsulation systems slow down the degradation of AST to a certain extent and can be applied to different food systems. However, studies and applications are still focused on emulsions and microcapsules with unsatisfactory odor masking effects. In the future, diverse AST-loaded delivery systems with high encapsulation efficacy, good stability, odor masking effects and cost-effective preparation technologies will be the major research trends.