Cytotoxic Activity of Halymenia durvillaei against Cervical Cancer Cells: In Vitro and Computational Evidence.

Cervical cancer remains a major global health burden, particularly in low- and middle-income countries, necessitating the discovery of novel, accessible anticancer agents. Marine macroalgae, including Halymenia durvillaei, are rich in bioactive compounds with promising therapeutic potential. H. durvillaei collected from North Sulawesi, Indonesia, was extracted with methanol and fractionated into n-hexane, chloroform, ethyl acetate, and aqueous fractions. Phytochemical profiling and cytotoxicity were assessed using the brine shrimp lethality test (15.625-1000 µg/mL) and MTT assay against HeLa cells treated with extract fractions (0.125-2 mg/mL) for 72 h. The most bioactive fraction was subjected to GC-MS characterization. Major compounds identified were evaluated through molecular docking against Vaccinia H1-related phosphatase (VHR; PDB ID: 3F81) using AutoDock Vina/CB-Dock2, followed by 100 ns molecular dynamics simulation and ADMET prediction. Phytochemical screening confirmed the presence of flavonoids (2.91 mg QE/g), alkaloids (1.03 mg/g), tannins, saponins, and steroids. The chloroform fraction exhibited the highest cytotoxicity (LC₅₀ = 33.83 µg/mL), while ethyl acetate, n-hexane, chloroform, and aqueous fractions inhibited 70-93% of HeLa cell proliferation. GC-MS analysis identified oleic acid as a major compound. In silico studies revealed stable binding of oleic acid to VHR phosphatase, a protein implicated in cervical cancer progression, supported by favorable ADMET properties. H. durvillaei demonstrates significant cytotoxic and antiproliferative activities, highlighting its potential as a source of natural anticancer agents. However, further compound isolation and mechanistic validation are required to confirm its therapeutic relevance.