In vitro antimicrobial activity of garlic, oregano and chitosan against Salmonella enterica

Food can harbour harmful pathogenic microorganisms, such as Salmonella spp. that are responsible by serious human illnesses. The use of natural antimicrobial substances can be practical to maintain the fresh image of food, to increase its shelf life, safety and marketability. We therefore evaluated the in vitro ability of three natural antimicrobial substances (garlic, oregano and chitosan) to inhibit S. enterica under different thermal conditions. All substances exhibited strong antibacterial activities at low temperature. Oregano had the strongest antibacterial properties, followed by chitosan and garlic. These results suggest that garlic, oregano and chitosan can be practical to protect food and consumers from the risk of contamination by S. enterica, to extend food shelf-life, to reduce food waste and to use in hurdle technologies at low temperature.