Effect of olive leaf powder prepared by steam explosion process on lipid absorption and bile acid reabsorption in the intestine

We examined the effects of olive leaf powder on cholesterol metabolism, using the rats fed on high cholesterol diets. The olive powder was treated by steam explosion. Besides a group of rats fed on a control diet (AIN93G), we made three groups fed on different kinds of high cholesterol diets : the basic one, the one containing the olive leaf powder (1.5% add), and another containing olive leaf extract (0.25% add). Through feeding the rats during the test period, the values of total bile acids and total lipids in the feces decreased significantly in the group fed on the olive leaf powder and that fed on the olive leaf extract. The values of total cholesterol in the feces and triglyceride in the liver decreased significantly in the group fed on the olive leaf extract. These results indicate that the olive leaf powder facilitates the lipid absorption and the bile acid reabsorption in the ileum. This function may be due to oleuropein, the major polyphenol in olive leaves.