Effects of Red, Green and Black Pepper on Intestinal Motility and Post-Prandial Bicarbonate Concentration in Guinea Pigs

Pepper is one of the most commonly used spices in most food cultures because of its many dietary and medicinal uses. The aim of the present study was to investigate and compare the effects of different varieties of pepper on intestinal motility and post-prandial serum bicarbonate concentration in guinea pigs. The study was carried out using 50 adult guinea pigs weighing 800-1000g, separated into groups of 5 each including group 1 which served as control. The experimental groups received respectively black, green and red pepper extracts in concentrations of 25mg/kg, 50mg/kg and 75mg/kg. For each experimental group, pepper was administered together with a mixture of Evans blue dye and Arabic gum and allowed for one hour. Each animal was thereafter, anesthetized and the intestines dissected out. For each animal, the total length of the intestine as well as the distance travelled by the test meal from the pyloric sphincter were measured and recorded. Intestinal transit was expressed as the percentage of the distance travelled by the test meal to the total length of the intestine. Concomitantly, blood samples were collected to determine the post-prandial bicarbonate concentration. The result showed that all three varieties of pepper caused significant rise in percentage intestinal transit (in 1hr) and by implication reduction in the intestinal transit time. However, a significant dose-dependent effect was observed in the groups receiving black and green pepper respectively but not in the red category. This suggests an inverse relationship between the concentrations of black and green pepper with the intestinal transit time. Pepper did not cause any significant change in the plasma post-prandial bicarbonate concentrations. Conclusively, the results suggest that black, green and red pepper respectively increased intestinal motility without possibly causing any significant effect on gastric acid secretion.