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Objective： This study aimed to improve the preservation properties of pullulan （PUL） coating and prepare preservation materials with sustained-release properties. Methods： GSE nanoparticles were prepared by grape seed extract （GSE）, chitosan and γ-polyglutamic acid. GSE nanoparticles of different quality were added to the PUL coating solution to prepare GSE nanoparticles/PUL coatings. The preservation properties of GSE nanoparticles/PUL coatings on salmon fillets were evaluated. Results： Compared with untreated fish fillets, the total number of bacteria in fish meat was reduced, and lipid oxidation and protein decomposition were delayed by 1.08% GSE nanoparticles/PUL coating. In addition, after fish fillets were treated with 1.08% GSE nanoparticles/PUR coating, the protein solubility was increased by 38.8%, and the activities of superoxide dismutase and glutathione peroxidase were increased by 4.02 U/mg and 0.20 U/g, respectively. Conclusion： The GSE nanoparticles/PUL coatings were prepared with good preservation properties, which can extend the shelf life of salmon fillets for 5~7 days.

Bacillus subtilis, a probiotic bacterium with engineering potential, is widely used for the expression of exogenous proteins. In this study, we utilized the integrative plasmid pDG364 to integrate the hemagglutinin–neuraminidase (HN) gene from Newcastle disease virus (NDV) into the genome of the B. subtilis 168 model strain. We successfully constructed a recombinant B. subtilis strain (designated B. subtilis RH) that displays a truncated HN antigen fragment on the surface of its spores and further evaluated its immunogenic effects in mice. Using ELISA, we quantified the levels of IgG in serum and secretory IgA (sIgA) in intestinal contents. The results revealed that the recombinant B. subtilis RH elicited robust specific mucosal and humoral immune responses in mice. Furthermore, B. subtilis RH demonstrated potential mucosal immune adjuvant properties by fostering the development of immune organs and augmenting the number of lymphocytes in the small intestinal villi. Additionally, the strain significantly upregulated the relative expression of inflammatory cytokines such as IL-1β, IL-6, IL-10, TNF-α, and IFN-γ in the small intestinal mucosa. In conclusion, the B. subtilis RH strain developed in this study exhibits promising mucosal immunogenic effects. It holds potential as a candidate for an anti-NDV mucosal subunit vaccine and offers a novel preventive strategy for the poultry industry against this disease. [ABSTRACT FROM AUTHOR]

There is an increasing interest in the affine formation control of multi-agent systems, because it can change the centroid, orientation and scale of the formation by controlling only a few leaders. In this paper, the fault-tolerant affine formation control problem is addressed for double-integrator multi-agent systems with partial loss of efficiency and bias faults. Firstly, in order to track the leaders with dynamically changing accelerations, an acceleration observer with prescribed time convergence is proposed, which can estimate the ideal acceleration for each follower. Then, based on the acceleration observer, a fault-tolerant control algorithm is given. A new Lyapunov function candidate is constructed, based on which a sufficient condition to achieve the control objective is derived. Theoretical analysis shows that the formation tracking error can converge to zero within a prescribed time, and remain in a small neighborhood of zero after that time. Finally, numerical simulations are given to show the effectiveness of the proposed algorithm and compare it with existing results. [ABSTRACT FROM AUTHOR]