Antioxidant Activities and Phenolics Contents of Garcinia talbotii Fruit Rind

Background and Objective: There is growing interest in search for safer and more effective antioxidants from natural sources. Processing of G. talbotti fruit generates rinds as a waste. Aim of the present investigation was to determine phenolics content and antioxidant activities of different extracts prepared from fruit rinds of G. talbotii. Materials and Methods: Six solvents of different polarities (hexane, chloroform, ethyl acetate, methanol, water and hydro-alcohol (methanol: water, 2:8) were used for the extract preparation. Total phenolics content in extract samples was determined by Folin-Ciocalteu method. Three assays namely 2, 2-diphenyl-1-picrylhydrazyl (DPPH) free radical scavenging activity, 2-2'-Azino-bis (3-ethylbenzothiazoline-6-sulfonic acid) diammonium salt (ABTS) free radical scavenging activity and reducing power were used to assess the antioxidant activities of extracts in vitro. Trolox and gallic acid were used as positive control for comparing the antioxidant activities of the extracts. Results: The results demonstrated that total phenolics content was the highest in hexane extract and lowest in water extract. Moreover, extracts prepared with non-polar/medium polar solvent such as hexane, chloroform and ethyl acetate showed significantly higher antioxidant activities. Extracts prepared with polar solvents such as water and hydro-alcohol mixture showed moderate antioxidant activities in all three in vitro antioxidant assays. Conclusion: Extraction yield, total phenolics content and antioxidant activities varied on the polarity of the solvent used for extract preparation. Based on the results of present investigation, suitable solvent could be selected for preparation of extract with high phenolics and antioxidant activity.