Abstract

The present study investigated the in- vivo and vitro bioactivities of the essential oil of Duguetia lanceolata branches (EODL) and caryophyllene oxide (CO). The chemical composition of EODL was analyzed by GC and GC/MS. Acetic acid-induced writhing, formalin, hot plate and tail-immersion methods were used to evaluate the antinociceptive effect in mice. Anti-inflammatory activity was tested by carrageenan-induced paw edema and pleurisy in rats, and in mouse models of acute ear inflammation induced by croton oil and arachidonic acid. 2,2-Diphenyl-1-picrylhydrazyl (DPPH), reducing power and 𝛽-carotene bleaching assays were used to determine the antioxidant bioactivity. -Elemene, caryophyllene oxide and -eudesmol were the major components found in EODL. When tested, EODL and CO reduced the number of writhes and both phases of the time of paw licking, while the reaction time on a hot plate and the pain latency duration by the tail-immersion assay were increased. EODL and CO were effective against the paw edema, exudate volume, leucocyte migration and ear edema. EODL and CO also showed in vitro antioxidant activity. These results suggest that caryophyllene oxide is one of the active compounds found in EODL and could partially justify the bioactivity of this oil.

Key words: Duguetia lanceolata, essential oil, caryophyllene oxide, antinociceptive activity, anti-inflammatory activity, antioxidant activity.