Goniothalamus lanceolatus (Bân) Mat-Salleh is an ethnomedicinal plant indigenous to Sarawak, Malaysia used as traditional remedy for cancer by the local people but has not been previously studied, chemically or biologically. Interestingly, comprehensive UHPLC-MS profiling of the root extract detects presence of alkaloidal components in addition to the well-known styryl lactones and acetogenins, usually present in Goniothalamus species. Evaluation of fractions obtained from the dichloromethane root extract showed cytotoxic activities against three panels of cancer cell lines, which are the human breast cell lines (MCF-7, MDA-MB-231 and MDA-MB-468), human colon cell lines (HT29, HCT116 and SW48) and lung cancer cell lines (A549, NCI-H23, and NCI-H1299). Guided by the cytotoxic activities, herein we report isolation of lactam alkaloid 1 and quinone alkaloid 2, together with a known styryl lactone, 9-deoxygoniopypyrone 3, from the roots G. lanceolatus. Compound 1 showed strong cytotoxic effect on human lung and human colon cancer cell lines with IC50 values ranging from 5.32 to 9.91µM.
