SCREENING OF IN-VITRO ANTIOXIDANT, BRINE SHRIMP LETHALITY BIOASSAY AND ANTIMICROBIAL ACTIVITIES OF EXTRACTS OF BRIDELIA RETUSA (L.) SPRENG. FRUIT

Tufikul Islam*, Mohammad Raquibul Hasan, Aumit Roy, Md. Shafiqul Islam, Md. Afaz Uddin, Md. Ariful Islam, Md. Nuruzzaman Neon, Md. Sohel Rana

The objective of present study was to investigate the antioxidant, brine shrimp lethality and antimicrobial activities of Bridelia retusa (L.) Spreng. fruit using n-hexane, ethyl acetate and methanol extracts. Several methods were used for assessing antioxidant activity. In total phenol content determination methanolic extract showed highest value of 134.5 mg/g as Gallic Acid Equivalent (GAE). N-hexane extract showed highest total flavonoid content with 60.50±4.95 mg/gm as Quarcetin Equivalent (QE). Methanolic extract showed highest tannin content with 652.50±3.53 mg/gm as Tannic Acid Equivalent (TAE) and total anti-oxidant capacity with 236.00±36.78 mg/gm as Ascorbic Acid Equivalent (AAE). Methanolic extracts showed good DPPH free radical scavenging activity with IC₅₀ of 168.757 μg/mL. Ethyl acetate extract showed highest reducing capacity in CUPRAC test. Methanolic extracts showed good cytotoxic activity with IC₅₀ value of 20 μg/ml in brine shrimp lethality bioassay. In antimicrobial assay extracts showed poor activity. Further studies are needed to isolate active compounds.