Abstract

Phytochemical investigation of the fruit extract of Clausena excavata Burm. f. resulted in the isolation and identification of 16 compounds, including seven coumarins (1–7), four phenylpropanoids (8–10 and 14), two benzaldehyde derivatives (11 and 12), one carbazole alkaloid (13), and two limonoids (15 and 16). Of these, nine compounds (1, 3, 5, 6, 8–10, 15, and 16) were isolated from C. excavata for the first time. The absolute configuration of limonoids 15 and 16 was established by X-ray diffraction analysis using Cu Kα radiation. Some isolated compounds were evaluated for their in vitro cytotoxicity against three human cancer cell lines, namely lung cancer A549, colorectal cancer SW480, leukemic K562 cells as well as glucose uptake, glucose consumption, and antibacterial activity against Staphylococcus aureus (SA) and methicillin-resistant Staphylococcus aureus (MRSA). Compounds 7 (auraptene) and 14 (safrole) showed moderate glucose uptake with ratios of 1.38-fold and 1.41-fold compared to the positive control (metformin, 2.25-fold). Compound 7 (auraptene) also exhibited weak cytotoxicity against lung cancer A549, colorectal cancer SW480, and leukemic K562 cells with IC<inf>50</inf> values of 77.2, 157.3, and 105.3 µM, respectively, while compounds 8 ((E)-piperonylprop-2-enal) and 10 (ethyl p-coumarate) exhibited weak cytotoxicity against RAW 264.7 cells and colorectal cancer SW480 cells with IC<inf>50</inf> values of 234.9 and 219.5 μM, respectively. Compounds 1, 3, 7, and 14–16 showed a MIC of >512 µg/mL revealing them to be inactive.