Chowdhury et al., IJPSR, 2012; Vol. 3(7): 2263-2268 ISSN: 0975-8232 Available online on www.ijpsr.com 2263 IJPSR (2012), Vol. 3, Issue 07 (Research Article) Received on 19 March, 2012; received in revised form 22 June, 2012; accepted 26 June, 2012 IN-VITRO ANTIOXIDANT AND CYTOTOXIC POTENTIAL OF HYDROMETHANOLIC EXTRACT OF AVERRHOA BILIMBI L. FRUITS Sabiha Sultana Chowdhury* 1, 2 , Golam Mezbah Uddin 1, 3 , Nazia Mumtahana 1 , Mokarram Hossain 4 and S.M. Raquibul Hasan 4 Department of Pharmacy, Stamford University Bangladesh 1 , Dhaka-1217, Bangladesh Division of Food & Life Science, Pukyong National University 2 , Busan, South Korea Functional Food Center, Korea Institute of Science and Technology (KIST) Gangneung Institute 3 , Gangneung 210- 340, Korea Department of Pharmacy, BRAC University 4 , 66 Mohakhali, Dhaka-1212, Bangladesh ABSTRACT Averrhoa bilimbi Linn. (Family: Oxalidiaceae) is a medicinal plant which is extensively used in traditional medicine to cure cough, cold, itches, boils, rheumatism, syphilis, diabetes, whooping cough, and hypertension. In this study, hydromethanolic extract of A. bilimbi fruits was examined for its antioxidant action using 1, 1-diphenyl-2-picrylhydrazyl (DPPH) radical scavenging and total antioxidant capacity. Total phenol and flavonoid contents of the extract were also estimated. Moreover, brine shrimp lethality bioassay was used to investigate the cytotoxic potential of A. bilimbi. The extract exhibited strong DPPH radical scavenging activity with and IC 50 value of 20.35μg/ml as opposed to the IC 50 value of the reference standard, ascorbic acid (12.6μg/ml). It also displayed remarkable total antioxidant capacity (417.093±6.577mg/g in ascorbic acid equivalent (AAE)). Total phenol and total flavonoid contents of the extract were 106.16±2.818 mg/g in gallic acid equivalent (GAE) and 276.73±25.25 mg/g in quercetin equivalent (QE), respectively. A. bilimbi fruit extract also showed strong cytotoxic potential with an LC 50 value of 5.011μg/ml in brine shrimp lethality bioassay. Our results suggest that, in addition to having cytotoxic potential, A. bilimbi fruits are rich in polyphenolic antioxidants with strong radical scavenging capacity. INTRODUCTION: Different cellular and extracellular macromolecules such as proteins, lipids, and nucleic acids are damaged through oxidative stress resultant from the tipping of balance toward prooxidant status. Age-related diseases include macular degeneration, cancer, coronary heart disease and neurodegenerative disorders such as Alzheimer’s disease is the effect of cellular damage because of the production of reactive oxygen species (ROS) 1, 2 . It is generally assumed that frequent consumption of plant-derived phytochemicals from vegetables, fruits, tea, and herbs may contribute to shift the balance toward an adequate antioxidant status. Currently, the possible toxicity of synthetic antioxidants has been criticized 3 . Medicinal plants with a long history of use in treating cancer are overplaying an integral role in cancer chemotherapy in recent years. Of all available anticancer drugs between 1940 and 2002, 40% were natural products or natural product-derived with another 8% considered natural product mimics 4 . Keywords: Antioxidant, Cytotoxicity, Averrhoa bilimbi Linn, Total phenolic content, Total flavonoid content, Oxalidiaceae Correspondence to Author: Sabiha Sultana Chowdhury Department of food Science & Nutrition, Pukyong National University, Busan 608- 737, Republic of Korea