Antimicrobial activity of composite chitosan biofilms with beeswax and caraway essential oil

Abstract

In this paper, influence of increasing concentrations of beeswax on the antimicrobial activity of chitosan-caraway essential oil biofilm was investigated. Selected microorganisms for the test were Salmonella Typhimurium and Listeria monocytogenes. Reduction of S. Typhimurium and L. monocythogenes viable counts in bacterial suspension in the presence of chitosan films with or without added beeswax amounted over 80 % after 24 h contact time, and over 95 % after 3 h of contact time, respectively and influence of added beeswax on growth reduction was not detected. However, when number of S. Typhimurium viable cells was analyzed (log CFU/ml), it was shown that addition of beeswax led to increased activity of films, especially for the films with 36 kg/m3 and 54 kg/m3of beeswax. When films were transferred, after 24 h in bacterial suspension, onto Petri dishes with nutrient agar and incubated for 24 h on 37°C, results also showed beeswax contribution to growth inhibition of S. Typhimurium.

Keywords

• chitosan film
• essential oil
• beeswax
• antimicrobial activity
• s.typhimurium
• l. monocytogenes