Astaxanthin-loaded liposomes were prepared by a thin-film ultrasonic method, and the effects of the different membrane surface modifiers chitosan hydrochloride (CH) and lactoferrin (LF) on the physicochemical stability of the liposomes and bioaccessibility of astaxanthin were studied. Based on the negative charge characteristics of egg yolk lecithin, LF and CH with positive charge were assembled on the surface of liposomes by an electrostatic deposition method. The optimal concentrations of modifiers were determined by particle size, zeta potential and encapsulation efficiency. The interaction between the liposomes and the coatings was characterized by Fourier Transform infrared spectroscopy. The stability of astaxanthin in different systems (suspension and liposomes) was investigated, and its antioxidant capacity and bioaccessibility were determined. The results showed that both membrane surface modifications could interact with liposomes and protect astaxanthin from oxidation or heat degradation and enhance the antioxidant activity of the liposome, therefore membrane surface modification played an important role in stabilizing the lipid bilayer. At the same time, the encapsulated astaxanthin exhibited higher in vitro bioaccessibility than the free astaxanthin. CH and LF modified liposomes can be developed as formulations for encapsulation and delivery of functional ingredients, providing a theoretical basis for the development of new astaxanthin series products.

In recent years, the biological functions of human milk oligosaccharides and the potential toxic effects of red meat on human health have attracted considerable attention. Sialic acid is an important carbohydrate in milk and red meat, corresponding to sialylated oligosaccharides and N-glycolylneuraminic acid (NeuGc, one type of sialic acid). Herein, we reviewed the metabolic fate of dietary sialic acid in the body and their effects on gut and oral microbes. In summary, dietary NeuAc monomer is directly excreted through urine after being assimilated through the intestines and is not utilized by the human body; in contrast, dietary NeuGc from red meat is easily utilized by the human body and can be incorporated into the brain and other organs. Sialoglycans can be partially utilized by the human body, but they do not affect the cognitive development and growth of children. Dietary sialic acid may mainly regulate the growth and metabolism of gastrointestinal microbiota and human health and development through the gut-brain axis.

Textiles can be contaminated with pathogens during household laundering, potentially leading to human sickness. In this work, chitosan (CTS) was used as a substrate to prepare Ag/Cu-CTS composite, which was applied in laundering and showed a remarkable antibacterial effect on Escherichia coli and Staphylococcus aureus. The mechanical strength of Ag/Cu-CTS composite beads was higher than 400 MPa. The Ag/Cu-CTS composite were further characterized by scanning electron microscopy and energy dispersive spectroscopy. This composite had a strong inhibitory effect on several laundry pathogens, such as Acinetobacter sp., Pseudomonas aeruginosa, and Candida albicans. Using a standard laundering program and 15 g of Ag/Cu-CTS composite beads, the antibacterial rates reached 99.9%, and no silver emission was detected, thereby satisfying the Chinese requirement for washing machines. After 160 runs of laundering tests, this composite still has an excellent antibacterial effect. For the first time, chitosan is successfully applied as an antibacterial material on household electric appliances.