Nisin A is widely used as a natural preservative in the food industry due to its ability to inhibit the growth of a broad spectrum of Gram-positive bacteria, including spoilage organisms and foodborne pathogens like Listeria monocytogenes. It is commonly applied in dairy products, such as cheese and milk, to extend shelf life and maintain product safety. Additionally, it is utilized in canned foods, processed meats, and beverages to prevent microbial contamination. Its effectiveness at low concentrations and its natural origin make it a preferred choice for clean-label and organic food products. Nisin A is also employed in the pharmaceutical and cosmetic industries for its antimicrobial properties, helping to preserve formulations and prevent bacterial growth. Its stability under high-temperature processing further enhances its applicability in various heat-treated products.