Triterpenoids in olives

Reductions in blood sugar and blood lipids, anticarcinogenic activity

Horst Schmandke, Nuthetal

Olives contain 14 mg erythrodiol, 377–420 mg oleanolic acid and 681–1 073 mg maslinic acid per kg. Depending on their acidity, native olive oils can contain up to 138 mg/kg erythrodiol, up to 344 mg/kg oleanolic acid and up to 251 mg/kg maslinic acid. Native olive oils of the Extra grade contain only traces of erythrodiol and up to 85 mg/kg oleanolic acid.

The triterpenoids are largely eliminated when the oils are refined. Oleanolic and maslinic acids can be isolated by solvent extraction of the residues from pressing and centrifugation. Only about 0.7 % of orally ingested oleanolic acid is absorbed. 7% of this is eliminated in 24 h urine. Oleanolic acid is metabolised in the liver by hydroxylation. Triterpenoids inhibit the growth of several human cancer cell lines and of malignant tumours in the mouse and rat.

Oral oleanolic acid reduces the blood glucose concentration by 40 % and the insulin concentration by 47 %. On the other hand, intraperitoneal oleanolic acid enhances insulin secretion. Orally administered oleanolic acid reduced serum cholesterol in models of hyperlipidaemia in different animals, coupled to decreases in LDL and increases in HDL.

Keywords: Olives, olive oil, triterpenoids, blood sugar reduction, blood lipid reduction, cancer prevention

Sie finden den Artikel in deutscher Sprache in Ernährungs Umschau 02/09 ab Seite 92.