Antioxidant, allelopathic activities of leaf extracts and essential oil compositions of Acronychia pedunculata (L.) Miq.

Abstract

This research aims to exploit total polyphenol, flavonoid contents, antioxidant and allelopathic activities of leaf extracts, and essential oil compositions from leaves of Acronychia pedunculata (L.) Miq. The results indicated that the leaf extract from ethanol 100% (E100) possessed a lower total polyphenol and flavonoid content than the extract from ethanol 70% (E70). In contrast, the antioxidant activity from E100 extract with IC₅₀=612.9±12.9 µg/ml was stronger than that of E70 extract with IC₅₀=1225.5±6.9 µg/ml. Regarding allelopathic activity, while the extracts from E100 and E70 inhibited root growth of radish, both extracts promoted root growth of lettuce. Especially, E100 extract with 3 mg/ml inhibited root growth of radish up to 48.1%. Moreover, using water solvents, the extracts reduced root growth of both the radish and lettuce. By GC-MS analyses, 33 compounds were identified from A. pedunculata essential oil. The major constituents were caryophyllene (47.09%), humulene (17.28%), α-copaene (4.98%), isoledene (3.59%), and (-)-α-panasinsen (3.51%), other compounds were accounted for lower 3%.