Antioxidant activities of leaf galls extracts of Terminalia chebula (Gaertn.) Retz. (Combretaceae)

Free radicals are implicated in several metabolic diseases and the antioxidant therapy has gained an utmost importance in the treatment. The medicinal properties of plants have been investigated and explored for their potent antioxidant activities to counteract metabolic disorders. In this study, the chemical composition and free radical scavenging potential of leaf gall extracts (ethanol, petroleum ether, chloroform and aqueous) of Terminelia chebula is evaluated, which is extensively used in the preparation of traditiona medications to treat various metabolic diseases.

The presences of phenolics, flavonoids, triterpens, saponins, glycosides, phytosterols, reducing sugars were identified in the extracts according to standard procedures. The free radical scavenging activities of the extract were also analysed by standard procedures.

The methanol extract had the highest total phenolic and flavonoid content. The antioxidant activities of leaf gall extracts were examined using diphenylpicrylhydrazyl (DPPH), Super oxide radical scavenging, Hydroxyl scavenging and ferric reducing power (FRAP) methods. In all the methods, the ethanolic extract showed higher free radical scavenging potential than all the other extracts.

As the higher content of both total phenolics and flavonoids were found in the ethanolic extract, so the significantly high antioxidant activity can be positively correlated to the high content of total polyphenols/flavonoids of the ethanol extract. The results of this study confirm the folklore use of T. chebula leaves gall extracts as a natural antioxidant and justify its ethnobotanical use. Further, the results of antioxidant properties encourage the use of T. chebula leave gall extracts for medicinal health, functional food and nutraceutical applications.