Melissa officinalis as gut contractility modifier in swine—An ex vivo study

Diarrheal symptom provoked by intestinal disorders is a significant problem causing huge economic loss in swine production, especially at weaning and post-weaning age. Among solutions, spasmolytic resulting in smoothing gastrointestinal tract musculature is generally considered as contributor to reduce diarrhea. This study aimed to evaluate the antispasmodic effects of a natural standardized Melissa officinalis extract (Nor-Balm) and its major active substances on swine intestine. The experiments were conducted on circular and longitudinal colon samples collected from routinely slaughtered pigs. The effect of the standardized Melissa officinalis extract, rosmarinic and lithospermic acids on spontaneous and ACh-induced activity was evaluated under isometric conditions. The results revealed significant and dose-dependent potency of Melissa extract to decrease the magnitude of acetylcholine-induced contraction. The impact was slightly stronger on longitudinal than circular colon smooth muscle. Besides, the extract enhanced spontaneous contractility in longitudinal muscle layer. In case of rosmarinic and lithospermic acids the spontaneous colon motility was dose-dependently increased. Rosmarinic acid inhibited remarkably the contraction induced by ACh in both muscle types, whereas lithospermic caused increased and decreased response to ACh in circular and longitudinal colon muscles, respectively. The results of the performed study indicate that Melissa officinalis extract is efficient to control gastrointestinal motility. In which, rosmarinic acid seems contributing largely to the final effect of the plant extract. The ability to smooth intestinal muscle contraction revealed its potential in antidiarrheal effect in pigs. Further field studies should be carried to conform this assumption.

Key Words: Melissa officinalis, antispasmodic, diarrhea, lemon balm, anticontractility.

Presented at the 9th Symposium on Gut Health in Production of Food Animals, St. Louis, USA, 2021. For information on the next edition, click here.