Pharmacokinetics of maslinic and oleanolic acids from olive oil - Effects on endothelial function in healthy adults. A randomized, controlled, dose-response study.

To date, pharmacokinetics of maslinic (MA) and oleanolic (OA) acids, at normal dietary intakes in humans, have not been evaluated, and data concerning their bioactive effects are scarce. We assessed MA and OA pharmacokinetics after ingestion of olive oils (OOs) with high and low triterpenic acid contents, and specifically the effect of triterpenes on endothelial function. We performed a double-blind, dose-response, randomized, cross-over nutritional intervention in healthy adults, and observed that MA and OA increased in biological fluids in a dose-dependent manner. MA bioavailability was greater than that of OA, and consumption of pentacyclic triterpenes was associated with improved endothelial function. To the best of our knowledge, this is the first time MA pharmacokinetics, and effects on endothelial function in vivo, have been reported in humans.

Liquid chromatography tandem mass spectrometric determination of triterpenes in human fluids: Evaluation of markers of dietary intake of olive oil and metabolic disposition of oleanolic acid and maslinic acid in humans.

Olive oil is rich in several minor components like maslinic (MA) and oleanolic (OA) acids which have cardioprotective, antitumor, and anti-inflammatory properties. In order to assess the health benefits in humans provided by the olive oil triterpenes (MA and OA), suitable analytical methods able to quantify the low concentrations expected in human fluids are required. In this study, the LC-MS/MS quantification of both OA and MA in plasma and urine has been evaluated. The plasmatic method is based on the direct determination of the analytes. The urinary detection requires more sensitivity which was reached by derivatization with 2-picolylamine. Additionally, the urinary species present after MA and OA ingestion were evaluated by the direct detection of several phase II metabolites previously synthesized. Our results showed that OA is metabolized as both sulfate and glucuronide conjugates whereas MA is mainly excreted as glucuronide. Based on this information, the method for the urinary detection of MA and OA involved an enzymatic hydrolysis. Both plasmatic and urinary methods were validated with suitable precision and accuracy at all tested levels. Required sensitivity was achieved in both matrices. Up to our knowledge, this is the first method able to quantify the low concentration levels of triterpenes present in urine. Samples from two healthy volunteers who received virgin olive oils with different triterpenes content were analyzed. Some preliminary clues on the metabolic disposition of OA and MA after olive oil intake are provided.

The NUTRAOLEOUM Study, a randomized controlled trial, for achieving nutritional added value for olive oils.

BACKGROUND: Virgin olive oil, a recognized healthy food, cannot be consumed in great quantities. We aim to assess in humans whether an optimized virgin olive oil with high phenolic content (OVOO, 429 mg/Kg) and a functional one (FOO), both rich in phenolic compounds (429 mg/Kg) and triterpenic acids (389 mg/kg), could provide health benefits additional to those supplied a by a standard virgin olive oil (VOO). METHODS/DESIGN: A randomized, double-blind, crossover, controlled study will be conducted. Healthy volunteers (aged 20 to 50) will be randomized into one of three groups of daily raw olive oil consumption: VOO, OVOO, and FOO (30 mL/d). Olive oils will be administered over 3-week periods preceded by 2-week washout ones. The main outcomes will be markers of lipid and DNA oxidation, inflammation, and vascular damage. A bioavailability and dose-response study will be nested within this sustained- consumption one. It will be made up of 18 volunteers and be performed at two stages after a single dose of each olive oil. Endothelial function and nitric oxide will be assessed at baseline and at 4 h and 6 h after olive oil single dose ingestion. DISCUSSION: For the first time the NUTRAOLEUM Study will provide first level evidence on the health benefits in vivo in humans of olive oil triterpenes (oleanolic and maslinic acid) in addition to their bioavailability and disposition. TRIAL REGISTRATION: The Trial has been registered in ClinicalTrials.gov ID: NCT02520739 .

Antioxidant activity of ethanolic extracts from several asparagus cultivars.

Three different methods (antiradical activity, inhibition of primary oxidation, and ferric reducing power) have been used to evaluate the antioxidant activity of eight different asparagus cultivars and byproducts: white and green asparagus from Alcalá del Río (Guadalquivir Valley, Seville) and American hybrids, native spears, and their byproducts from Huétor-Tájar (Vega de Granada). The correlation between antioxidant activity and total phenol content was studied. Six standards were also tested to validate the modified methods for antioxidant activity determination. Results obtained for antiradical capacity and reducing power were very similar, and a high correlation with phenols was found (R > or = 0.9 for both tests). Sample origin was an important factor, spears from Huétor-Tájar having higher values (ARC between 7 and 10 and P(R) of 0.25-0.33) than those from Alcalá del Río (ARC 0.6-2 and P(R) of 0.05-0.07). Significant differences were found between spears with the same origin, suggesting that genetics are another factor to take into account. Asparagus inhibits lipid primary oxidation, but no correlation between the inhibition percentage and phenols was observed. Asparagus origin was the only factor that led to significant differences: samples from Huétor-Tájar had higher values (POIC between 18 and 32) than those from Alcalá del Río (POIC of 5-9). Byproducts from the canning industry at Huétor-Tájar were also assayed for antioxidant activity; the results obtained suggested that byproducts could be considered as an excellent source of natural antioxidants.