Antidiarrhoeal and antispasmodic activities of essential oil of Myrtus communisL. (Myrtaceae))
The use of the essential oil of Myrtus communis L. (myrtle) for different illnesses including diarrohea and dysentery is documented in folklore medicine. However, the scientific bases for this usage are not yet established. The main objective of this study was therefore to investigate the antidiarroheal and antispasmodic activities of the essential oil of M. communis (EOMC) in rodents by using different experimental models. EOMC was evaluated for its antidiarroheal and antispasmodic potential using a host of paradigms, including normal and castor oil-induced intestinal transit in mice; castor oil-induced diarrohea in mice, prostaglandin induced enteropooling in rats, and contractile response using Guinea pig ileum (GPI). Atropine was used in isolated preparation and normal intestinal transit test as a positive control, whereas loperamide was used in the castor oil-induced intestinal transit and castor oil-induced antidiarroheal test. All doses (100, 200 and 400 mg/kg) of EOMC significantly (p<0.05) inhibited normal intestinal transit as well as exhibited significant antidiarroheal and antienteropooling activities, where the effects were comparable with that of the positive controls employed. The oil also displayed significant reductions in acetylcholine-induced contractions of GPI. The agonist-induced contractions of GPI were greatly reduced by both concentrations; 50 μg/ml (p<0.01) and 100 μg/ml (p<0.01), suggesting a good spasmolytic property of the oil. The study suggested that the essential oil of M. communis possesses spasmolytic and antidiarroheal properties, providing support for the traditional use of the plant for stomach pains, and diarrohea. However, further study should be conducted in order to determine the exact mechanism(s) of action of the oil and also to characterize the constituents responsible for the activity observed.
Keywords: Myrtus communis, essential oil, antidiarroheal, antispasmodic, antienteropooling