Antibiofilm Activity of Probiotic Strains against Aggregatibacter actinomycetemcomitans

Aggregatibacter actinomycetemcomitans is a significant agent for periodontal disease. It develops biofilms on gingival plaque and promotes chronic pro-inflammatory response to periodontal tissues. As bacterial cells within the biofilm, this pathogen successfully eluded the human immune system by preventing the uptake of biofilm cells by phagocytic cells. Antibiotic-resistant biofilms might harm the environment, increase mortality, and add to the cost of healthcare. Anti-biofilms are necessary to prevent the growth of biofilms. It has been demonstrated that probiotics change how immune system cells produce cytokines. Therefore, the efficacy of five probiotic lactobacillus strains to prevent A. actinomycetemcomitans from growing bacteria and forming biofilms was evaluated. The organisms were incubated in anaerobic conditions at 37°C for a certain period. The antimicrobial test was done using the lawn method and measuring the size of the inhibition zone produced by the probiotic spots for each probiotic strain. Tetracycline antibiotic disc was used as a positive control to compare the size of the inhibition zone. The antibiofilm activity was performed using probiotic strains at their exponential and stationary phases against the exponential phase of A. actinomycetemcomitans. Our finding showed the probiotic lactobacillus could inhibit the growth of A. actinomycetemcomitans. The highest inhibition was demonstrated by L. johnsonii NBRC 13952. Besides, all probiotic lactobacillus used for this study significantly (p<0.05) inhibited the A. actinomycetemcomitans biofilm using both stationary and exponential phases. In conclusion, probiotic lactobacillus might be a potential agent that can be used to counteract the periodontal pathogen biofilm. Further study should be done to elucidate the antibiofilm mechanism, and several trials of the probiotic lactobacilli against multiple species of biofilms might be helpful in evaluating their effectiveness.