Cytotoxic, antioxidant and phytochemical analysis of Gracilaria species from Persian Gulf

Marine algae, also called seaweeds, are abundantly present in the coastal area of Iran, especially in Persian Gulf. These plants contain important phytochemical constituents and have potential biological activities. The present study investigated the presence of phytochemical constituents and total phenolic quantification of the seaweeds Gracilaria salicornia and Gracilaria corticata. Cytotoxicity of seaweeds was tested against HT‑29, HeLa, and MCF‑7 cell lines. Antioxidant potential of these two Gracilaria species was also analyzed.

Extracts of G. salicornia and G. corticata were subjected to phytochemical and cytotoxicity tests. Phytochemical screenings were employed to identify the chemical constituents and total phenolic content. Cytotoxicity was characterized by IC50 of human cancer cell lines (MCF‑7, HeLa, and HT‑29) using sulforhodamine assay. Antioxidant activities were evaluated using 2,2‑diphenyl‑1‑picrylhydrazyl.

The analysis revealed that tannins were the most abundant compounds in G. corticata while sterols and triterpenes were the most abundant ones in G. salicornia, but the total phenolic content of the two seaweeds was similar. Cytotoxic results showed that both species could inhibit cell growth effectively, especially against HT‑29 cell line.

Considerable phytochemicals, high antioxidant potential, and moderate cytotoxic activity of G. salicornia and G. corticata make them appropriate candidates for further studies and identification of their bioactive principles.