Unveiling the essential oil composition and bioactivities of Piper frustratum Boerl.

This study aimed to investigate the chemical composition, and anticholinesterase and anti-tyrosinase activities of the essential oil extracted from the leaves of Piper frustratum Boerl., growing in Malaysia. Nineteen chemical components were identified using gas chromatography-flame ionization detection (GC-FID) and gas chromatography-mass spectrometry (GC-MS), accounting for 99.6 % of the essential oil. The identified major components include β-caryophyllene (12.6 %), β-asarone (10.7 %), myristicin (10.4 %), α-copaene (9.6 %), methyl eugenol (7.2 %), and β-cubebene (6.5 %). Anticholinesterase activity was assessed using the Ellman's method, while anti-tyrosinase activity was evaluated against mushroom tyrosinase. The essential oil demonstrated moderate inhibitory activity against acetylcholinesterase (IC₅₀ value of 84.2 μg/mL), butyrylcholinesterase (IC₅₀ value of 98.5 μg/mL), and tyrosinase (IC₅₀ value of 95.4 μg/mL) enzymes. This study is the first to report the chemical composition and bioactivities of the essential oil obtained from P. frustratum, which may have implications on the characterization, pharmaceutical, and therapeutic applications of Piper essential oils.