Gracilariopsis persica from Persian Gulf Contains Bioactive Sterols

Gracilariopsis Persica (Rhodophyta) is one of the most abundant algae, introduced newly from the Indian Ocean. In this study, the main sterols of the algae have been isolated and identified. Separation and purification of the compounds was carried out on silica gel and sephadex LH(20) column chromatography (CC) and high performance liquid chromatography (HPLC) to obtain five pure compounds 1-5. Structural elucidation of the compounds was based on the data obtained from H-NMR, (13)C-NMR, DEPT and Mass spectroscopy. The separated compounds from Gp. Persica were identified as 22-dehydrocholesterol (1), cholesterol (2), stigmasterol (3), β-sitosterol (4) and fucosterol (5) based on the spectral data compared to those reported in literatures. Most of these sterols are noteworthy for their effectiveness in decreasing the plasma cholesterol, glucose and inflammation. The results of Brine Shrimp Cytotoxicity Assay indicated that the ethyl acetate extract of Gp. Persica showed a high cytotoxic effect against A. salina nauplii (LC(50) = 4 μg/mL). The methanol extract was no effective but the aqueous methanol extract was moderately effective (LC(50 )= 40 μg/mL) compared to berberine hydrochloride as a positive control (LC(50) = 26 μg/mL).