Marine macroalgae with antioxidant, antimicrobial and cytotoxic potential

In the present investigation the acetone extracts of three marine macroalgae Laurentia obtusa, Codium elongatum and Cutleria multifida were tested for antioxidant, antimicrobial and cytotoxic potential. Antioxidant activity was evaluated by free radical scavenging, superoxide anion radical scavenging and reducing power. C. elongatum extract had most potent free radical scavenging activity (IC50=382.45 μg/ml). Moreover, the tested extracts had effective reducing power and superoxide anion radical scavenging. Total content of phenol and flavonoid in extracts were examined using FolinCiocalteu reagent and by aluminium chloride method, respectively. Further, the antimicrobial potential was determined by a microdilution method. Among the tested species, extract of L. obtusa showed the best antimicrobial activity with minimum inhibitory concentration values ranging from 0.156 to 5 mg ml. Finally, the cytotoxic activity was tested using MTT method. Extract of L. obtusa expressed stronger cytotoxic activity toward tested cell lines with IC50 values ranging from 38.63 to 67.62μg/ml. Key-Words: Acetone extracts; Anticancer activity; Antimicrobial activity; Antioxidant activity; Algae.