Composition and anti‐inflammatory activities of Zanthoxylum schinifolium essential oil: suppression of inducible nitric oxide synthase, cyclooxygenase‐2, cytokines and cellular adhesion

BACKROUND: The chemical composition of Zanthoxylum schinifolium essential oil (EO) was analysed by gas chromatography/mass spectroscopy (GC/MS). To date, the biological functions of Z. schinifolium EO have not been demonstrated scientifically. We investigated the composition of Z. schinifolium EO and its potential anti‐inflammatory effects including iNOS and COX‐2 gene transcription, the production of cytokines IL‐1β and IL‐6, and the cellular adhesion. RESULTS: Over 55 compounds were detected in Z. schinifolium EO, and β‐phellandrene, citronellal, and geranyl acetate were identified as the major constituents. Z. schinifolium EO and its constituents suppressed significantly gene transcription of the inducible nitric oxide synthase and cyclooxygenase‐2 from lipopolysaccharide (LPS)‐induced RAW 264.7 cells. In addition, Z. schinifolium EO inhibited interleukin‐1β production in LPS‐stimulated macrophage cells. The suppression of E‐selectin gene transcription by Z. schinifolium EO caused the cellular adhesion of THP‐1 monocytes to HUVEC monolayers. CONCLUSION: This study suggests that Z. schinifolium EO may be useful as an alternative medicine for the relief and retardation of immunological inflammatory responses, as well as aromatherapy, and its action may occur through the reduction of inflammatory mediators.