Trilliumosides K and L, Two Novel Steroidal Saponins from Rhizomes of , As Potent Anti-cancer Agents Targeting Apoptosis in the A-549 Cancer Cell Line

Two novel steroidal saponins, trilliumosides K () and L (), were isolated from the rhizomes of led by bioactivity-guided phytochemical investigation along with seven known compounds: govanoside D (), protodioscin (), borassoside E (), 20-hydroxyecdysone (), 5,20-hydroxyecdysone (), govanic acid (), and diosgenin (). The structure of novel compounds 1-2 was established using analysis of spectroscopic data including 1D and 2D nuclear magnetic resonance (NMR) and high resolution mass spectrometry (HR-ESI-MS) data. All isolated compounds were evaluated for cytotoxic activity against a panel of human cancer cell lines. Compound showed significant cytotoxic activity against the A-549 (Lung) and SW-620 (Colon) cancer cell lines with IC50 values of 1.83 and 1.85 µM, respectively whereas the IC50 value of Compound against the A-549 cell line was found to be 1.79 µM. Among the previously known compounds , , and , the cytotoxic IC50 values were found to be in the range of 5-10 µM. Comprehensive anti-cancer investigation revealed that Compound inhibited migration and colony-forming capability in the A-549 cell line. Additionally, the mechanistic analysis of Compound on the A-549 cell line indicated distinctive alterations in nuclear morphology, increased reactive oxygen species (ROS) production, and decreased levels of mitochondrial membrane potential (MMP). By upregulating the pro-apoptotic protein BAX and downregulating the anti-apoptotic protein BCL-2, the aforementioned actions eventually cause apoptosis, a crucial hallmark in cancer research, which activates Caspase-3. To the best of our knowledge, this study reports the first mechanistic anti-cancer evaluation of the compounds isolated from the rhizomes of with remarkable cytotoxic activity in the desired micromolar range.