DOI: 10.36347/sajb.2013.v01i02.003

Pages: 50-54

Abstract: This study examined the free radical scavenging potential of crude water, ethanol and isopropanol extracts of leaves of Camellia sinensis (Fam: Theaceae) or black tea leaves in vitro. Pharmacological history of this plant inspired us to evaluate the possible antioxidant activity. Free radical scavenging activity was evaluated in vitro with the spectrophotometric method based on the reduction of the stable 1,1-diphenyl-2-picryl-hydrazyl (DPPH) free radical. The tested extracts showed variable antioxidant activities. The highest antioxidant activity was achieved in water (48.32%) followed by ethanol (37.80%) and isopropanol (32.96%) extracts. The extracts were investigated regarding their total flavonoid content (TFC) by A1C13 reagent. The aqueous extracts of black tea leaves (TFC = 53.16 ± 1.95 µg/mg) and ethanol extracts (TFC = 46.97 ± 4.43 µg/mg) had the highest content of flavonoid whereas isopropanol extracts had minor (TFC = 10.81 ± 1.98 µg/mg) content. Furthermore, the total phenolic content of the three extracts of black tea leaves showed large variations. The water extracts of black tea leaves contained the highest total phenol content (156.00 ± 0.62 mg GAE/g extract), followed by ethanol extracts (123.33 ± 2.32 mg GAE/g extract) and isopropanol extracts (82.37 ± 1.12 mg GAE/g extract).This study suggests that leaves of black tea are the possible sources of natural radical scavengers. Thus black tea leaves could be used as natural antioxidants in the beverage, food and pharmaceutical industries that need further wide range in vivo studies.