Reuterin is a broad-spectrum antimicrobial substance produced by the bacterium Lactobacillus reuteri. It inhibits a wide range of spoilage organisms and foodborne pathogens, which has made it interesting as a potential natural food preservative. Researchers are exploring how reuterin-producing cultures could protect fermented foods and extend shelf life without synthetic additives. Because it is generated in situ by a food-grade bacterium, it fits clean-label preservation strategies, although practical application still requires work on production levels, stability in foods, and regulatory acceptance.