Chito-oligosaccharides (COSs) were encapsulated by the film-ultrasonic method into three nano-liposomes, which were uncoated liposomes (COSs-Lip), chitosan-coated liposomes (CH-COSs-Lip), and sodium alginate (SA)/chitosan (CH)-coated liposomes (SA/CH-COSs-Lip). The physicochemical and structural properties, as well as the stability and digestive characteristics, of all three nano-liposomes were assessed in the current study. Thereafter, the characteristics of intestinal absorption and transport of nano-liposomes were investigated by the Caco-2 cell monolayer. All nano-liposomes showed a smaller-sized distribution with a higher encapsulation efficiency. The ζ-potential, Z-average diameter (Dz), and polydispersity index (PDI) demonstrated that the stability of the SA/CH-COSs-Lip had much better stability than COSs-Lip and CH-COSs-Lip. In addition, the transport of the nano-liposomes via the Caco-2 cell monolayer indicated a higher transmembrane transport capacity. In summary, the chitosan and sodium alginate could serve as potential delivery systems for COSs to fortify functional foods and medicines.
Appropriate pretreatment of proteins and addition of xanthan gum (XG) has the potential to improve the stability of oil-in-water (O/W) emulsions. However, the factors that regulate the enhancement and the mechanism are still not clear, which restricts the realization of improving the emulsion stability by directional design of its structure. Therefore, the effects of whey protein micro-gel particles (WPMPs) and WPMPs-XG complexes on the stability of O/W emulsion were investigated in this article to provide theoretical support. WPMPs with different structures were prepared by pretreatment (controlled high-speed shear treatment of heat-set WPC gels) at pH 3.5–8.5. The impact of initial WPC structure and XG addition on Turbiscan Indexes, mean droplet size and the peroxide values of O/W emulsions was investigated. The results indicate that WPMPs and XG can respectively inhibit droplet coalescence and gravitational separation to improve the physical stability of WPC-stabilized O/W emulsions. The pretreatment significantly enhanced the oxidative stability of WPC-stabilized O/W emulsions. The addition of XG did not necessarily enhance the oxidative stability of O/W emulsions. Whether the oxidative stability of the O/W emulsion with XG is increased or decreased depends on the interface structure of the protein-XG complex. This study has significant implications for the development of novel structures containing lipid phases that are susceptible to oxidation.
6 May 2021 in International Journal of Food Science and Technology
This study explored the effect and underlying mechanisms of different molecular weights of konjac glucomannan (KGM) on the structure and gel properties of Antarctic krill myofibrillar proteins (MP) during various durations of frozen storage. As the duration of frozen storage increased from 0 to 180 days, the total SH content and tensile properties of the MP complex gel exhibited a decline trend. However, the addition of KGM, HMW-KGM (high molecular weight, KGM), MMW-KGM (medium molecular weight, KGM), and LMW-KGM (low molecular weight, KGM) significantly mitigated the variations in the structural and rheological properties of the MP and KGM-MP complex gel. Furthermore, the total sulfhydryl (SH) content, Ca2+-ATPase activity, ζ-potential, and α-helix content of the secondary structure of MP significantly enhanced, with the maximum values observed upon the addition of MMW-KGM. Observations of microstructure and rheological properties also indicated that the incorporation of MMW-KGM stabilized the microstructure of the MP complex gel and maintained the highest storage modulus (G′) value. The utilization of konjac oligosaccharide showed prospective industrial applications in the quality improvement of Antarctic krill.
Wound healing is a complicated process that involves hemostasis, antibacterial defense, and tissue regeneration. Conventional treatment methods, such as surgical suturing, have inherent limitations, necessitating the exploration of new ones. Hydrogels can create a moist environment that facilitates wound healing, making them an ideal material for wound healing. In this study, a procoagulant polysaccharide mixture (carboxymethyl chitosan/sodium alginate/fucoidan; CAF) was designed. Hydrogels were prepared using CAF and an oxidized starch/tannic acid blend (OT) at different ratios. Through comprehensive evaluations, such as gelation time, swelling capacity, and antibacterial efficacy, an optimal hydrogel (COT) was identified. This COT hydrogel was formed by mixing 3% CAF and OT solutions at a ratio of 2:1 (v/v). The associated gelation process occurred rapidly within 13 s. COT hydrogel exhibited self-healing properties, and a high swelling rate (~3109 ± 74%). It also demonstrated high antibacterial activity, facilitating enhanced protection against infection. Additionally, COT hydrogel exhibited biocompatibility and biosafety. COT hydrogel demonstrated low cytotoxicity on mice fibroblast cells (L929) and good hemocompatibility in vitro. Moreover, in vivo evaluations revealed that it did not cause skin irritation or allergic reactions. Importantly, COT hydrogel significantly outperformed the commercially available hydrogel with its hemostatic and wound healing performance (p < 0.001, p < 0.01).
The body wall of sea cucumbers is rich in nutrients and small-molecule metabolites; however, traditional hot water pretreatment often leads to nutrient loss. To optimise processing techniques, this study compared the effects of microwave pretreatment and conventional hot water pretreatment on nutrient retention and metabolite profiles. Untreated sea cucumber body wall samples served as controls. The samples were subjected to microwave pretreatment (4 W/g, 12 min) or hot water pretreatment (100 °C, 10 min). Nutrient retention rates and metabolite variations were systematically analysed. Microwave pretreatment demonstrated superior retention of protein (96%), crude fat (92%), total sugar (55%), and saponins (40%). It also promotes the accumulation of small-molecule metabolites, including spermidine, tagatose, and melatonin. Notably, the lysine and methionine retention rates were enhanced by 10-fold and 12-fold, respectively, while the vitamin A, vitamin B3, and melatonin retention increased by 2.4-fold, 2-fold, and 3-fold, significantly outperforming traditional pretreatment. These findings highlight the potential of microwave pretreatment as an efficient alternative to conventional methods for preserving the nutritional and functional components of sea cucumbers.