Efficacy of Psidium guajava and Allium sativum extracts as antimicrobial agents against periodontal pathogens

Background: The accumulation and maturation of bacterial plaque at the gingival margin is widely recognized as the primary etiological factor in the development of chronic periodontitis. With the rise in bacterial resistance to antibiotics, there is considerable interest in the development of other classes of antimicrobials for the control of infection. Aim: The aim of this study was to evaluate the efficacy of Psidium guajava (guava) and Allium sativum (garlic) on Porphyromonas gingivalis and Aggregatibacter actinomycetemcomitans. Materials and Methods: Aqueous guava extract (AGvE), ethanolic guava extract (EGvE), aqueous garlic extract (AGE), and ethanolic garlic extract (EGE) were prepared. The inhibitory effects of these extracts for the periodontal pathogens were tested by agar well diffusion method. Minimal inhibitory concentration (MIC) of the aqueous and ethanol extracts of guava and garlic was determined by macrobroth dilution method. Minimum bactericidal concentration (MBC) was done to observe the bactericidal effect of the guava and garlic extracts against the organisms. Results: Of the AGE, 25, 50, and 75 μL showed 16, 20, and 25 mm zone of inhibition, respectively, on P. gingivalis. The AGE showed greater bacteriostatic activity against the P. gingivalis with MIC determined at 16.6 μL/mL. MIC determined for AGvE and EGvE was at 75 μL/mL concentration for P. gingivalis, whereas EGvE showed the activity at 75 μL/mL on P. gingivalis. MIC determined for AGvE was at 50 μL/mL, whereas MIC determined for EGvE was at 3.12 μL/mL for A. actinomycetemcomitans. Conclusion: P. guajava and A. sativum displayed a significant antibacterial effect. A. sativum was found to be most effective against P. gingivalis, whereas P. guajava showed the highest efficacy on A. actinomycetemcomitans.