Phytochemical, cytotoxicity and antioxidant studies on the stem bark of Piper arborescens

Abstract

Phytochemical study on the stem bark of P. arborescens has isolated six secondary metabolites from the crude extracts by using column chromatography, while identification was performed by using Gas Chromatography - Mass Spectrometry (GC-MS), Nuclear Magnetic Resonance (NMR) and Fourier Transform Infrared (FTIR). The isolated metabolites were identified as caryophyllene oxide (1), α-bisabolol (2), benzamide 2-(methylamino) (3), 2-ethylpiperidine (4), piperine (5) and methyl eugenol (6). Toxicity test on the four crude extracts of P. arborescens shows a high cytotoxicity against Artemia salina brine shrimp with LC50 values ranging from 13.12 to 58.70 µg/mL. Greater cytotoxicity of the crude extracts of P. arborescens indicated the presence of potent cytotoxic components in this Piper spp. Antioxidant assay of P. arborescens against 2-diphenyl-1-picrylhydrazyl (DPPH) indicated moderate antioxidant activities of methanol, dichloromethane, chloroform and hexane crude extracts with EC50 values of 21.68, 23.82, 32.88 and 36.88 µg/mL, respectively.