Insight into chemical composition and bioactivity profiling of leaf essential oil from Litsea tomentosa Blume (Lauraceae)

This study explored the chemical composition and biological activities of the essential oil extracted from Litsea tomentosa Blume. Using chromatographic analysis, 44 chemical components, accounting for 99.1% of the oil, were identified. The predominant constituents were (E)-β-caryophyllene (31.0%), α-humulene (10.5%), methyl myrtenate (7.0%), α-gurjunene (6.6%), germacrene D (5.9%), and γ-muurolene (4.5%). The biological potential of the essential oil was assessed through various enzymatic assays. Acetylcholinesterase inhibition was evaluated using the Ellman method, antityrosinase activity was determined with mushroom tyrosinase, and anti-inflammatory activity was assessed using lipoxygenase enzymes. The essential oil exhibited notable bioactivity, demonstrating 50.3% inhibition of acetylcholinesterase, 47.6% inhibition of tyrosinase, and 52.8% inhibition of lipoxygenase. These findings suggest the potential of Litsea tomentosa essential oil as a source of natural enzyme inhibitors particularly sesquiterpenes such as (E)-β-caryophyllene and α-humulene, which exhibit neuroprotective (AChE-inhibitory), skin-whitening (tyrosinase-inhibitory), and anti-inflammatory (lipoxygenase-inhibitory) activities.