Context: Marine algae produce different secondary metabolites with a wide range of biological activities. Many studies have been achieved on the screening of biological effects of marine organisms and a lot of active compounds were isolated and characterized.
Aims: In an attempt to find cytotoxic compound of hexane fraction, isolation, identification, and cytotoxicity of active compound of this fraction were performed.
Materials and methods: In this study, total methanolic (70%) extract and partition fractions of hexane, chloroform (CHCl(3)), ethyl acetate (EtOAc), and MeOH-H(2)O of Sargassum angustifolium, Chondria dasyphylla, and Ulva flexuosa, collected from coastlines of the Persian Gulf in south of Iran, were studied against colon carcinoma (HT-29), colorectal adenocarcinoma (Caco-2), breast ductal carcinoma (T47D), and Swiss mouse embryo fibroblast (NIH 3T3) cell lines by MTT assay.
Statistical analysis used: IC(50) (median growth inhibitory concentration) values were calculated by Sigmaplot (10) software.
Results: Hexane fraction of Chondria dasyphylla (IC(50) 82.26 ± 4.09 μg/ml) and MeOH-H(2)O fraction of Ulva flexuosa (IC(50) 116.92 ± 8.58 μg/ml) showed cytotoxic activity against proliferation of T47D cells. Hexane fraction of Sargassum angustifolium was also observed for cytotoxicity against T47D and HT-29 cell lines (IC(50) 166.42 ± 26.7 and 190.24 ± 52.8 μg/ml), respectively. An investigation of a component from the hexane fraction of Sargassum angustifolium yielded a steroidal metabolite, fucosterol, with cytotoxicity in T47D and HT29 (IC(50) 27.94 ± 9.3 and 70.41 ± 7.5 μg/ml).
Conclusions: These results indicated that fucosterol, the most abundant phytosterol in brown algae, is responsible for cytotoxic effect of this extract against breast and colon carcinoma cell lines.
Keywords: Cytotoxic activity; Persian Gulf; fucosterol; marine algae.