Bioassay-guided isolation and identification of bioactive compound from aerial parts of Luffa acutangula against lung cancer cell line NCI-H460.

Luffa acutangula (Cucurbitaceae) is widely used as a traditional medicine in India and was reported to possess various pharmacological activities including its anti-proliferative effects. In this study, the bioactive compound of ethanolic extract of L. acutangula (LA) was isolated using bioassay-guided approach. Five major fractions were collected and evaluated for their anti-proliferative activity against non-small cell lung cancer cells (NCI-H460). Among the test fractions, the fraction LA/FII effectively decreased the growth of cancer cells with IC50 values of 10 µg/ml concentration. Furthermore, it significantly increased intracellular reactive oxygen species and decreased the mitochondrial membrane potential. The apoptogenic activity of fraction LA/FII was confirmed by cell shrinkage, membrane blebbing and formation of apoptotic bodies. A single bioactive compound was isolated from the active faction, LA/FII and subsequently identified as 1,8 dihydroxy-4-methylanthracene 9,10-dione (compound 1) by comparing its spectral data [Ultraviolet (UV), Infrared (IR), Nuclear magnetic resonance (NMR) and Electrospray Ionization-Mass Spectroscopy (ESI-MS)] with literature values. This is the first report on the isolation of compound 1 from this plant.