Ascorbic Acid Changes Growth of Food-Borne Pathogens in the Early Stage of Biofilm Formation

• Main Authors: Jana Przekwas, Natalia Wiktorczyk, Anna Budzyńska, Ewa Wałecka-Zacharska, Eugenia Gospodarek-Komkowska
• Format: Article
• Language: English
• Published: MDPI AG 2020-04-01
• Series: Microorganisms
• Subjects: vitamin C; ascorbic acid; biofilm; food; Listeria monocytogenes; Escherichia coli
• Online Access: https://www.mdpi.com/2076-2607/8/4/553

Since bacterial biofilm may contribute to the secondary contamination of food during the manufacturing/processing stage there is a need for new methods allowing its effective eradication. Application of food additives such as vitamin C already used in food industry as antioxidant food industry antioxidants may be a promising solution. The aim of this research was evaluation of the impact of vitamin C (ascorbic acid), in a range of concentrations 2.50 µg mL⁻¹–25.0 mg mL⁻¹, on biofilms of <i>Staphylococcus aureus</i>, <i>Escherichia coli</i>, and <i>Listeria monocytogenes</i> strains isolated from food. The efficacy of ascorbic acid was assessed based on the reduction of optical density (<i>λ</i> = 595 nm). The greatest elimination of the biofilm was achieved at the concentration of vitamin C of 25.0 mg mL⁻¹. The effect of the vitamin C on biofilm, however, was strain dependent. The concentration of 25.0 mg mL^-1 reduced 93.4%, 74.9%, and 40.5% of <i>E. coli</i>,<i> L. monocytogenes</i>,<i> </i>and <i>S. aureus </i>number, respectively. For <i>E. coli</i> and <i>S. aureus</i> lower concentrations were ineffective. In turn, for <i>L.</i><i> </i><i>monocytogenes</i> the biofilm inhibition was observed even at the concentration of 0.25 mg mL⁻¹. The addition of vitamin C may be helpful in the elimination of bacterial biofilms. Nonetheless, some concentrations can induce growth of the pathogens, posing risk for the consumers’ health.