Antimicrobial Potential and Determination of Total Phenolic and Flavonoid Content of Aerial Part Extracts of Ajuga bracteosa Wall ex. Benth

Background: Traditionally, Ajuga bracteosa (family Lamiaceae) has been used to cure many diseases including gout, rheumatism, amenorrhea, diabetes, malaria, inflammation and cancer in different parts of the world. The antimicrobial activity of the plant has not been validated as yet. This study aims at validation of the folklore use of the plant as a broad spectrum anti-infective agent. Objective: To determine the total phenolic and flavonoid contents and to evaluate the antimicrobial activity using different bacterial and fungal strains. Materials and Methods: Total phenolic and flavonoid content was measured spectrometrically using Folin-Ciocalteau reagent and by aluminium chloride colorimetric methods respectively. Antimicrobial activity was evaluated by standard agar well and disc diffusion methods. Results: The phenolic and flavonoid contents were found highest in the methanolic extract (337.26 mg GAE/g and 213.52 mg RE/g respectively). A relationship was found between flavonoid and phenolic content with biological activity. The extracts also showed good antibacterial and antifungal activity. Salmonella typhi (MTCC 1688) was the most sensitive organism tested. Conclusion: The results demonstrate that Ajuga bracteosa contains high content of phenolics and flavonoids making it a promising candidate for further investigation and development as a natural broad spectrum antimicrobial agent.