In-vitro antioxidant activity, total phenolic, flavonoid and tannin contents in the Ajuga bracteosa wall. Ex benth, grown at middle hill climatic condition of Western Himalayas

Abstract

The antioxidant activity of aqueous and alcoholic extracts of different plant parts viz, leaves, flower, stem and root of Ajuga bracteosa was investigated against various in-vitro antioxidant assays. The total phenolic, flavonoid and tannin contents also estimated. The results revealed the significant antioxidant potential and variation in the IC50, EC50 and phytochemical contents among all the plant parts. The aqueous extract of leaves exhibited significantly (P<0.05) highest antioxidant activity on 2,2-azino-bis-(3-ethylbenzothiazoline-6-sulphonic acixd), 2,2-diphenyl-1-picryl hydrazyl, and potassium ferricyanide reducing power assay, with IC50 values of 0.2707±0.0008, 0.4409±0.0020, and EC50 value 0.3413±0.0030 mg/mL, respectively, followed by the other parts of the plant. The leaves extract also possess the highest total phenolics, flavonoid and tannin contents among all the parts. Similarly, the aqueous extract is better than the alcoholic extract of different parts as far as phytochemical contents and antioxidant activity concerned. The present study revealed that the aqueous extract of leaves had the highest antioxidant potential, which correlated with the high level of total phenolic flavonoid, and tannin contents. Therefore, higher the phytochemical contents, higher will be the antioxidant potential.