Identification of compounds with anti-proliferative activity from the wood of Ficus elastica Roxb. ex Hornem. aerial roots

The natural products from plants still remain an important source of pharmaceuticals. In the current study, methanolic wood extracts of Ficus elastica Roxb. ex Hornem. (Moraceae) aerial roots were screened for anti-cancer activity. Using bioassay-guided fractionation, three new compounds, elasticamide (1), elastiquinone (2) and ficusoside B (3), together with four known compounds, were isolated. The structures of the new compounds were established by means of extensive spectroscopic analyses (1D and 2D NMR, HR-ESI-MS, as well as IR and UV) and by comparison of their spectroscopic data with those reported for structurally related molecules. The isolated compounds were afterwards evaluated for their anti-proliferative effect on six human cancer cell lines (U373n and Hs683 glioblastoma, MCF7 and A549 NSCLC carcinoma, and B16F10 and SK-MEL-28 melanoma) using colorimetric MTT assay. Most notably, elastiquinone (2) showed cytotoxic activity with IC50 = 14 μM against B16F10 melanoma cells, whereas the peracetylated form of ficusoside B (3a) displayed the lowest IC50 value (11 μM) against U373n glioma cell lines. Elasticamide (1) and ficusoside B (3) exhibited a weak cytotoxicity with IC50 values ≥ 88 μM. The results of this investigation demonstrate that the wood of F. elastica aerial roots might be a potential source for identifying new compounds with potent anti-proliferative activity.

Phytochemical investigation using bioassay-guided fractionation has led to the isolation of three new compounds (1–3) from the wood of Ficus elastica aerial roots. MeOH extract and fractions 2 and 3 showed cytotoxic activities against U373n, A549 NSCLC and SK-MEL-28 cancer cell lines with IC50 ranging from 3 to 8 μg/mL. Compound 2 (IC50 of 14 μM against B16F10 melanoma cells) and 3a (IC50 of 11 μM against U373n glioma cells) had moderate activity while compounds 1 and 3 exhibited weak cytotoxicity with IC50 value ≥ 88 μM.Figure optionsDownload high-quality image (334 K)Download as PowerPoint slide