Prophylactic Protection Against Salmonella typhimurium Infection by Single-Atom Zinc Catalysts

Zinc oxide promotes poultry growth, but it tends to agglomerate. This necessitates high doses and leads to environmental contamination from unabsorbed, excreted zinc. Undigested zinc is excreted and can enter the food chain, increasing the probability of zinc residues in edible poultry tissues (muscle, liver, and eggs) and raising concerns for consumer safety. MOF-supported single-atom zinc catalysts (SAC) resolve agglomeration by atomic anchoring, enhancing bioavailability. High-temperature/high-pressure fixation of Zn²⁺ surfaces was confirmed by XRD, while FESEM revealed the corresponding surface morphology, collectively verifying SAC formation. SAC exhibited potent antimicrobial efficacy against key pathogens such as Salmonella typhimurium, Escherichia coli, and Staphylococcus aureus (MIC of 3.125 mg/mL, MBC of 25 mg/mL). Co-culture experiments further demonstrated that the antibacterial performance of SAC remained stable over a temperature range of 20-80 °C and a pH range of 2-8, thus exhibiting excellent thermal stability and gastrointestinal tolerance. In 7-day-old chicks, SAC alleviated S. typhimurium-induced inflammation, reduced bacterial adherence, upregulated claudin-1, preserved gut homeostasis, ameliorated tissue lesions, and increased the abundance of Lactobacillus in the cecum, demonstrating promising potential for poultry infection control.