Macroalgae are known for their antibacterial and antioxidant properties. In the Ica Region (southern Peru), various macroalgae species, such as Ulva lactuca and Caulerpa filiformis, thrive along the coastline. This study aimed to evaluate the cytotoxic activity of extracts and fractions from Ulva lactuca and Caulerpa filiformis on human cancer cell lines including AGS (gastric), DU-145 (prostate), MDA-MB-231 and MDA-MB-468 cells (breast).
Two extractions and six fractions (50μg/mL) were screened for cytotoxicity using the MTT assay. Then, using the most cytotoxic fractions, the half-maximal inhibitory concentration (IC50) was calculated using two-fold dilution concentrations ranging from 50 to 1.56 μg/mL. The IC50 for F5 was found to be 4.08 ± 1.40 μg/mL at 24 hours and 7.05 ± 1.57 μg/mL at 48 hours for AGS cells. For F6, IC50 values were 18.9 ± 1.12 μg/mL at 24 hours and 5.32 ± 1.27 μg/mL at 48 hours for AGS. These findings suggest that Ulva lactuca and Caulerpa filiformis contain bioactive compounds with potential cytotoxic effects, warranting further investigation for their use in anticancer therapies.