Bioassay-Guided Fractionation and Antimicrobial Activities of Padina australis Extracts

Background: Marine seaweeds synthesize different metabolites with various biological activities, including antimicrobial effects. Objectives: The main object of this study was to fractionate the seaweed Padina australis and analyze activities these fractions isolate bioactive compounds. Methods: collected from Persian Gulf extracted by maceration methanol-ethyl acetate solvent. extract evaporated partitioned Kupchan method yield hexane, dichloromethane, water, butanol partitions. Dichloromethane partition further fractionated MPLC, activity crude extracts all were investigated using disc diffusion agar plate count methods. MIC values chloroform, partitions calculated. Results: Fraction numbers 11, 4, 7 showed highest inhibitory effect value 87 µg/mL, 156 µg/mL against E. coli, P. aeruginosa, S. aureus, respectively. Conclusions: This reveals that have microorganisms.