IN VITRO ASSESSSMENT OF ANTIOXIDANT AND ANTIMICROBIAL ACTIVITIES OF DIFFERENT SOLVENT EXTRACTS FROM LICHEN RAMALINA NERVULOSA Original Article

Objective: The purpose of the existent study is to assess the in vitro antioxidant and antimicrobial activity of different solvent extracts of Ramalina nervulosa. Methods: Folin ciocalteu’s and Aluminium chloride method were used for total phenolic and flavonoid content estimation respectively. The antioxidant activity was evaluated through free radical scavenging activity by DPPH (2, 2-diphenyl-1-picrylhydrazyl), FRAP (ferric ions reducing antioxidant potential), cupric ion chelation ability. Agar diffusion method was used to assess the antimicrobial capacity. GC-MS analysis was carried out to identify the presence of compounds in the extracts. Results: Ethanol extracts exhibited that the highest zone of inhibition with Bacillus subtilis, Proteus vulgaris, Pseudomonas aeruginosa, Klebsiella pneumoniae and with two fungal strains such as Fusarium oxyparum and Penicillium notatum. The extract also has high inhibition capacity of 64.29% and 62.49% towards DPPH and Cu2+ion respectively. But the aqueous extract showed higher amount of phenolic and flavonoid content of about 211.40 mg GAE/g dw and 50.72 mg QE/g dw respectively and Fe2+ Conclusion: The results of FRAP assay were positively correlated with the total phenolic and flavonoid content. Ethanol extracts of R. nervulosa showed promising antibacterial, antifungal and antioxidant activities which can be considered as the potent source of antioxidant product and offer protection from oxidative stress under many pathophysiological conditions. ion reducing capacity of about 144.41 mol ascorbic acid equivalent/g db. Further analysis of GC-MS showed the presence of various bioactive molecules present in the lichen Ramalina nervulosa.