VOLUME 63 : 2015

The ethanolic extract of the green alga Bornetella oligospora was sequentially fractionated with hexane, chloroform, ethyl acetate, and water, and concentrated in vacuo. Different concentrations of the fractions, ranging from 1 to 150 ppm, were prepared in 80% DMSO, and tested on sea urchin embryos at cleavage and free-swimming hatching. The chloroform concentrate at 150 ppm was the most potent in altering sea urchin embryonic development among fractions. The rate of cleavage in embryos exposed to this fraction was significantly inhibited. Moreover, anomalous morphological features were observed among treated embryos with less apoptosis during cleavage and no cell arrest during blastulation and the free-swimming larval stage. The motility of treated larvae was also slowed. All embryos exposed to 80% DMSO control remained unaffected. Preliminary phytochemical analysis detected the presence of terpenoids in the hexane, chloroform, and aqueous fractions. The ethyl acetate fraction tested positive for saponins. The chloroform fraction clearly altered embryonic development, which could be indicative of its potential chemotherapeutic activity since sea urchin embryos are used as a pre-screen model for determining potential anticancer property.

Keywords: bioactivity, embryotoxicity, marine natural products, secondary metabolites