Determination of maslinic acid, a pentacyclic triterpene from olives, in rat plasma by high-performance liquid chromatography.

Maslinic acid, a pentacyclic triterpene from olives, has been reported to exert beneficial effects on health, including anticarcinogenic activity. Despite its importance, little is known about its bioavailability in both humans and animals. A fundamental step for this evaluation consisted of measuring this compound in blood. Therefore, a simple high-performance liquid chromatography (HPLC) method with diode array detection has been developed. Maslinic acid contained in plasma was extracted twice using ethyl acetate. After centrifugation, the organic fraction was evaporated to dryness and the residue was reconstituted with methanol/water (75:25, v/v) and analyzed by HPLC. The method was validated by obtaining a linear correlation (r(2) = 0.999) and an average recovery of 99%. Precision expressed as the coefficient of variation ranged from 1.23 to 9.06%. The oral administration of maslinic acid (50 mg/kg) to rats and its subsequent detection in plasma showed that the method is suitable for absorption, distribution, and metabolism studies.