Effects of Erythroxylum macrocarpum (Erythroxylaceae), an endemic medicinal plant of Mauritius, on the transport of monosaccharide, amino acid and fluid across rat everted intestinal sacs in vitro

The use of herbal medicine is widespread and growing. Erythroxylum macrocarpum (Erythroxylaceae) (EM) is an endemic medicinal plant of Mauritius. Here, the effects of crude aqueous extract of EM leaves on D-glucose, Ltyrosine and fluid absorption, gut wall content and transport across rat everted intestinal sacs were investigated in vitro. Rat everted intestinal sacs were incubated with increasing graded concentrations of EM (1.5-12 mg/ml) in the mucosal solution. D-glucose absorption and transport was not significantly affected (p>0.05), whilst L-tyrosine transport was inhibited at 6 and 12 mg/ml of EM. The fluid absorptive capacity of the small intestine was decreased in the presence of 6 and 12 mg/ml of EM in the incubating buffer. It is hypothesised that active phytochemicals such tannins, phenols and alkaloids in the EM extract decreased the permeability of the enterocytes membrane and the energy independent transport of fluid. The present data also tend to validate the diuretic effect of EM.