Objectives: This study aimed to evaluate the variations of the chemical composition and bioactivity of essential oils of Liquidambar styraciflua L. (Altingiaceae) collected in different seasons.
Methods: The oils were analysed by GLC/FID and GLC/MS. The antioxidant activity was investigated by diphenylpicrylhydrazyl (DPPH) and superoxide anion radical scavenging assays and the deoxyribose degradation assay. Inhibition of both 5-lipoxygenase (5-LOX) and prostaglandin E2 (PGE2) production in hepatic cancer (HepG-2) cells were used to assess the anti-inflammatory activity. The cytotoxic activity was investigated using 3-(4,5-dimethylthiazol-2-yl)-2,5-diphenyltetrazolium bromide (MTT) assay.
Key findings: Altogether, 64 volatile secondary metabolites were identified. The major components of the leaf oil were d-limonene, α-pinene and β-pinene, and of the stem oil were germacrine D, α-cadinol, d-limonene, α-pinene, and β-pinene. Leaf and stem oils collected in spring could reduce DPPH● (IC50 = 3.17 and 2.19 mg/ml) and prevent the degradation of the deoxyribose sugar (IC50 = 17.55 and 14.29 μg/ml). The stem oil exhibited a higher inhibition of both 5-LOX and PGE2 than the leaf oil. The cytotoxic activity of leaf and stem oils was low in cancer cell lines (IC50 = 136.27 and 119.78 μg/ml in cervical cancer (HeLa) cells).
Conclusions: Essential oils of L. styraciflua exhibited an interesting anti-inflammatory activity with low cytotoxicity, supporting its traditional use to treat inflammation.
Keywords: Liquidambar styraciflua; anti-inflammatory; cytotoxicity; essential oils; seasonal variation.
© 2013 Royal Pharmaceutical Society.