LAUSR

Abstract Recently, macroalgae or seaweeds serve as a treasure of potential drugs for cancer therapy. The present study investigated the cytotoxic activity of eight compounds isolated from the brown alga Sargassum platycarpum for the first time. These isolates were identified as hexadecanoic acid (1), oleic acid (2), saringosterol (3 and 4, 1:1 mixture of C-24epimers), β-sitosterol (5), glycoglycerolipid (6), loliolide (7) and Kjellmanianone (8) by spectroscopic techniques. Two epimers of saringosterol, (24-R)-saringosterol (3) and (24-S)-saringosterol (4), were subsequently separated by HPLC. (24-S)-saringosterol (4) and (24-R)-saringosterol (3) exhibited potent cytotoxicity against HepG-2 cells with IC50 of 0.10±0.00 and 0.11±0.00 µM, respectively with compared to standard 5-Fluorouracil (IC50 of 0.63±0.28 µM) and other isolates. MEP, EHOMO, ELUMO and global properties of all isolated compounds are computed by DFT methods. Molecular docking study showed that most of the isolated compounds especially compounds 3 and 4 interact strongly with 4PYP with the highest binding energies maintained that the high cytotoxic activity of these compounds against HepG-2 cells in the experimental part. Bioactivity Score, Drug-Likeness and ADMET studies supported the potential biological activities of most isolated compounds especially compounds 3 and 4 and also created attention for developing them to act as good candidates.