Isolation, characterization, in silico docking, and in vitro cytotoxicity study of isolated triterpene constituents from Ehretia microphylla

Building on previous studies of Ehretia microphylla, we quantified key phytochemicals rutin, gallic acid, and quercetin using high-performance thin-layer chromatography (HPTLC), validated against standard references. From chloroform extract, three triterpenes were isolated and structurally characterized. These were identified as bauerenol (Compound A), 11-oxo amyrin (Compound B, a novel triterpene), and β-sitosterol (Compound C). In silico docking studies were performed with the cancer-related protein (PDB: 1DB1), yielding binding scores of −9.50, −9.44, and −7.44, and with the hepatoprotective target (PDB: 4FA6), with scores of −8.13, −8.42, and −8.54, respectively. Compounds A and B exhibited significant anticancer potential, while Compound C showed superior hepatoprotective activity. In vitro cytotoxicity studies on HepG2 cells revealed IC₅₀ values of 455, 538, and 556 μg/mL, and on NIH 3T3 cells, IC₅₀ values were 1068, 1153, and 1310 μg/mL, indicating selective toxicity toward cancer cells. These findings highlight the therapeutic potential of triterpenes from E. microphylla, with Compounds A and B for hepatocellular carcinoma treatment and Compound C for hepatoprotection.