Participation of citral in the bronchodilatory effect of ginger oil and possible mechanism of action

Fitoterapia. 2013 Sep;89:68-73. doi: 10.1016/j.fitote.2013.05.012. Epub 2013 May 17.


The extract of ginger, the rhizomes of Zingiber officinale Roscoe (Zingiberaceae), has been reported to possess anti-hyperactivity and anti-inflammation on airway. The present study described brochodilatory activity of ginger oil and identified its active compound. Ginger oil was extracted by hydro-distillation. The compositions of ginger oil were analyzed by gas chromatography and mass spectrometer. Citral, eucalyptol and camphene were found to be the major components. Ginger oil and citral, but not camphene, suppressed rat tracheal contraction induced by carbachol (CCh). Consistent with previous report, eucalyptol showed a relaxing effect on rat airway. Since the content of eucalyptol in ginger oil was relatively low, the contribution of eucalyptol to the bronchodilatory effect of ginger oil was small. To elucidate the mechanisms responsible for the myorelaxing effect, propranolol (a β-adrenergic receptor antagonist), indomethacin (a COX inhibitor) and L-NAME (a NOS inhibitor) were used to block the inhibitory effects of ginger oil and citral. It was found that propranolol, but not indomethacin and L-NAME, reversed bronchodilatory effects of both ginger oil and citral, suggesting that a possible mechanism involved β-adrenergic receptor. This study provides the pharmacological basis supporting the therapeutic potential of Z. officinale rhizomes as a bronchodilator.

Keywords: Bronchodilation; CCh; COX; Citral; GC/MS; Ginger oil; L-NAME; N(ω)-nitro-L-arginine methyl ester; NOS; Zingiber officinale; carbachol; cyclooxygenase; gas chromatography and mass spectrometry; nitric oxide synthase; β-Adrenoceptor.

Publication types

  • Research Support, Non-U.S. Gov't

MeSH terms

  • Acyclic Monoterpenes
  • Adrenergic beta-Agonists / analysis
  • Adrenergic beta-Agonists / pharmacology
  • Adrenergic beta-Antagonists / pharmacology
  • Animals
  • Bicyclic Monoterpenes
  • Bronchodilator Agents / analysis
  • Bronchodilator Agents / pharmacology*
  • Bronchodilator Agents / therapeutic use
  • Carbachol
  • Cyclohexanols / analysis
  • Cyclohexanols / pharmacology
  • Eucalyptol
  • Ginger / chemistry*
  • Male
  • Monoterpenes / analysis
  • Monoterpenes / pharmacology*
  • Monoterpenes / therapeutic use
  • Oils, Volatile / chemistry
  • Oils, Volatile / pharmacology*
  • Oils, Volatile / therapeutic use
  • Phytotherapy
  • Plant Extracts / chemistry
  • Plant Extracts / pharmacology*
  • Plant Extracts / therapeutic use
  • Propranolol / pharmacology
  • Rats
  • Receptors, Adrenergic, beta / metabolism*
  • Respiratory Tract Diseases / drug therapy
  • Respiratory Tract Diseases / metabolism*
  • Rhizome / chemistry
  • Terpenes / analysis
  • Terpenes / pharmacology
  • Trachea / drug effects


  • Acyclic Monoterpenes
  • Adrenergic beta-Agonists
  • Adrenergic beta-Antagonists
  • Bicyclic Monoterpenes
  • Bronchodilator Agents
  • Cyclohexanols
  • Monoterpenes
  • Oils, Volatile
  • Plant Extracts
  • Receptors, Adrenergic, beta
  • Terpenes
  • Carbachol
  • Propranolol
  • camphene
  • Eucalyptol
  • citral