Antimicrobial efficiency of photoactivated chlorophyllin-chitosan complex

摘要

The aim of this study was to assess the antimicrobial efficiency of a photoactivated chlorophyllin-chitozan complex against the food pathogen Salmonella enterica. Salmonella enterica was used for experiments. Aliquots of bacterial suspensions (～1 x 10~7 CFU/ml in 0.9 % NaCl) with 0.001 % chlorophyllin-0.1 % chitosan complex (Chl-CHS) were incubated in the dark at 37 °C for 0-120 min. For the photoactivation, the samples were exposed to light (A = 405 nm) for 30 min (light dose 17.3 J/cm~2). Microbial viability was evaluated by the spread plate method. The Chl-based photosensitization treatment reduced the bacterial population by 1.39 log. An extremely high antibacterial efficiency was demonstrated after photoactivation of the Chl-CHS complex (7.3 log reduction of microbial population). Experimental data support the idea that a photoactivated CHS-Chl complex in a slightly acidic environment can be a useful tool against the gram-negative bacteria S. enterica.