Investigating the influence of seasonal variations on biological activities is important for pharmacological studies and metabolic engineering. Therefore, this study was conducted to determine the variation of the chemical composition of essential oils obtained from Nectandra megapotamica leaves, collected at different stages of plant development, as well as its influence on the biological activities. A total of 38 compounds were identified that accounted for 97–99.2% of the chemical composition of the oils. Major differences were observed in the monoterpenic fraction, representing 5.1% of the compounds identified in the productive rest phase to 37.1% in the blooming phase. Bicyclogermacrene and germacrene D were the predominant compounds identified in the oil of all collections. Furthermore, limonene, β-pinene, and spathulenol were identified predominantly in the samples of blooming and fruiting phases. The oils exhibited significant antichemotactic activity and different effects in scavenging the radical 2,2-diphenyl-1-picrylhydrazyl. Variations were also observed in the antifungal activity, with the minimum inhibitory concentrations ranging from 125 to 500 μg/mL. These results demonstrate the influence of monoterpenes, primarily limonene, α-pinene, and β-pinene, on the bioactivities of the oil. Studies investigating the variations in the chemical composition of essential oil may offer a strategy to produce a compound or a group of compounds of interest to industries with a specific pharmacological focus.

Campomanesia xanthocarpa is a plant species traditionally used in the treatment of diabetes, fever, hypercholesterolemia, obesity, and urinary tract diseases. The anti-inflammatory effects of C. xanthocarpa leaves in mice were already known. Nevertheless, studies on the anti-inflammatory activity of its seeds are still lacking. The aim of this study was to investigate the anti-inflammatory activity and acute toxicity of C. xanthocarpa seed extract, obtained from supercritical CO₂ extraction (SCCO₂) at 40°C and 250 bar, in mice. GC/MS analysis revealed that β-caryophyllene is the major compound present in the C. xanthocarpa SCCO₂ extract. The extract (60mg/kg, p.o.) significantly reduced the nociceptive behavior in the second phase of the formalin test and prevented the paw oedema induced by carrageenan up to 6h after carrageenan injection. The extract (0.11μg/mL) inhibited neutrophils migration induced by LPS from E. coli in vitro. This antichemostatic effect was comparable to the effect of indomethacin. Acute administration (2000mg/kg, p.o.) of C. xanthocarpa SCCO₂ extract caused no mice mortality, demonstrating that the extract is devoid of acute toxicity. These data suggest that C. xanthocarpa seeds present anti-inflammatory activity and represent a source of anti-inflammatory compounds.