SCREENING STUDY OF THREE MEDICINAL PLANTS FOR THEIR ANTIOXIDANT AND CYTOTOXIC ACTIVITY

Plants have been used in traditional medicine for several thousand years since which may have been described to have curative value. Terminalia chebula (TC), Terminalia arjuna (TA) and Holarrhena antidysenterica (HA) are very important medicinal plants in the traditional Indian systems of Ayurveda and Siddha. In this work, fruit of Terminalia chebula, bark of Terminalia arjuna and Holarrhena antidysenterica were selected for experiments. 80% methanolic crude extracts of these plants were fractionated by diethyl ether and ethyl acetate. Diethyl ether fraction of 80% methanolic extract (DM) and ethyl acetate fraction of 80% methanolic extract (EM) of all the three plants were compared for their phyto-chemical, antioxidant and cytotoxicity to find out their therapeutic potential. The phenolic content was determined by Folin-Ciocalteu method and was found to be higher in Terminalia chebula extracts (>36 mg GAE/g)). The antioxidant activity was assayed through some in-vitro methods such as DPPH radical scavenging assay, phosphomolybdenum method and reducing power assay. Antioxidant activity was also found to be highest in Terminalia chebula extracts. Cytotoxicity of extracts was determined by the MTT assay using HeLa cell lines which showed that the increase in concentration of the extract increases the cell death. All the extracts showed moderate cytotoxicity with IC₅₀ values ranging from 147.91 to 1701 µg/ml. These findings showed that extracts from Terminalia chebula is a potential source of natural antioxidants and could be good alternatives to synthetic antioxidants in pharmaceutical industries.