Preserving biological functionality under cryogenic conditions remains essential across biotechnology, food, and healthcare sectors, yet conventional cryoprotectants such as dimethyl sulfoxide (DMSO) and glycerol pose significant cytotoxic and environmental concerns. Herein, a sustainable cryopreservation strategy based on hydrocolloid-like micro eutecto-vesicles (MEVs), fabricated via a facile centrifugal process using glucose/fructose (GF), proline/glucose (PG), and proline/sorbitol (PS) based natural deep eutectic solvents (NADESs), and sodium alginate (SA), was developed, which was dual bioinspired by cold-tolerant organisms and frog eggs. The results showed that the introduction of NADESs can improve the colloidal stability and uniformity of the MEVs preparation process, and the diameter of the MEVs obtained at 1000 rpm centrifugal speed was about 300 μm. The toxicity test for yeast showed that the components used were less toxic than glycerol and DMSO in terms of proliferation activity and ROS accumulation. For the evaluation of post-thaw cell viability, the cryoprotection of SA/PG based MEVs can achieve a survival rate of yeast cells higher than 92%, while ensuring the integrity of cell structure and excellent proliferation activity. The subsequent mechanism exploration showed that the colloidal vesicle structure of MEVs can reduce the formation of intercellular ice crystals during freezing and inhibit the recrystallization of ice crystals. This study presents a biocompatible, scalable, environmentally responsible, and food grade hydrocolloid-based platform for the long-term stabilization of biological systems, with direct implications for sustainable probiotic production, cold-chain logistics, and bioresource preservation.
Lingjun Tong,Haining Hao,Xinyi Zhang,Zhe Zhang,Youyou Lv,Lanwei Zhang,Huaxi Yi
Scope Milk-derived extracellular vesicles (mEVs) as nanoparticles are being developed as novel drug vehicles due to their pivotal role in cell–cell communication. As an important bioactive component in milk, little is known about their effect on the gut microbiota and intestinal immunity. Therefore, the effects of mEVs on gut microbiota and intestinal immunity in mice are investigated. Methods and results First, a new method to obtain high-yield mEVs is developed. Afterward, the colonic contents from C57BL/6 mice fed different doses of mEVs (8 weeks) are collected and the microbial composition via 16S rRNA gene sequencing is analyzed. It is found that mEVs could alter the gut microbiota composition and modulate their metabolites—short-chain fatty acids (SCFAs). Furthermore, the effects of mEVs on intestinal immunity are evaluated. It is observed that the expression levels of Muc2, RegIIIγ, Myd88, GATA4 genes, and IgA, sIgA are increased in the intestine, which are significant for the integrity of the mucus layer. Conclusion These findings reveal that the genes with critical importance for intestinal barrier function and immune regulation are modified in mice by oral administration mEVs, which also result in the changes of the relative composition of gut microbiome and SCFAs.
危险品化学品经营许可证（带存储）