Essential oils from <i>Acronychia pedunculata</i> (L.) Miq. in Vietnam: chemical composition, antimicrobial, cytotoxicity and nitric oxide inhibition activities

The chemical composition, antimicrobial, cytotoxic and anti-inflammatory activities of essential oils from different parts of <i>Acronychia pedunculata</i>, a medicinal plant native to Central Highlands of Vietnam, were investigated. Their chemical constituents were determined using GC-MS. The antimicrobial properties were assessed using a microdilution broth method, while the anti-inflammatory properties were measured based on their capacity to inhibit NO production in macrophage cells. Their cytotoxicity was tested using the sulforhodamine B assay on three human cancer cell lines. The GC-MS analysis revealed the presence mainly of caryophyllene oxide (35.3%) and spathulenol (31.9%) in the stem essential oil, caryophyllene oxide (51.3%), and linalool (21.0%) in the leaf essential oil, and α-pinene (21.4%), (E)-β-ocimene (16.5%), linalool (12.5%), and β-caryophyllene (13.0%) in the fruit essential oil. All three essential oils inhibited the growth of various bacteria and fungi, reduced NO production in LPS-induced RAW264.7 cells, and exhibited cytotoxicity against all three tested cancer cell lines. Notably, the fruit essential oil showed the most potent cytotoxicity among the essential oils, with IC₅₀ values of 5.47 ± 0.21, 7.95 ± 0.35, and 9.22 ± 0.52 g/mL against SK-LU-1, MCF-7, and HepG2 cells, respectively. It also had a strong anti-inflammatory effect that was comparable to that of dexamethasone, with an IC₅₀ value of NO production inhibition of 14.62 ± 0.62 mg/mL. These results suggest the potential of the essential oils from this plant to provide leads for the development of anti-inflammatory and anti-cancer agents.