Evaluation of Biopolymers with Plant Extracts on Periodontopathogen microorganisms

Objectives: The aim of this work was the development of a local delivery system and evaluate the antimicrobial properties of two natural polymers (Chitosan and Pullulan) added with extracts of Thymus vulgaris, Croton lechleri and Julliana adstringens Schl. against Porphyromonas gingivalis and Aggregatibacter actinomycetemcomitans, the most frequent causative agents of periodontitis. Methods: Three different formulations of each polymer were tested to obtain the best properties for the production of films. Chitosan was used in concentrations of about 1%, 1.2% and 0.8%. Pullulan was used at 10%, 12% and 10% plus sorbitol (as plasticizer). The best formulation for each polymer were selected and added in concentrations of about 80 mg/ml of T. vulgaris, 60 mg/ml J. adstringens Schl and 90 mg/ml C. lechleri. The method used was "casting" pouring the formulation in acrylic molds, distributing the mix with a spoon extension and drying at room temperature. Films were recovered manually after 24h. The discs (6 mm in diameter) of polymers added with the extracts where placed on the inoculated plates. Antimicrobial activity was evaluated by measuring the zone of inhibition against the tested organisms. Results: Pullulan added with T. vulgaris showed zones of growth inhibition about 15mm of diameter, while J. adstringens Schl. showed 13mm for A. actinomycetemcomitans. Pullulan with T. vulgaris and C. lechleri had 14mm for P. gingivalis. Chitosan with C. lechleri showed inhibition zones of 13mm for A. actinomycetemcomitans and 11mm on P. gingivalis. The biopolymers without extracts have good inhibitory effects on Porphyromonas gingivalis and Aggregatibacter actinomycetemcomitans cultures. Conclusions: Our findings suggest on the use of Chitosan and Pullulan showed synergistic activity with Thymus vulgaris, Croton lechleri and Julliana adstringens Schl. extracts for antimicrobial inhibition of Porphyromonas gingivalis and Aggregatibacter actinomycetemcomitans and have potential application as drug delivery systems.