The study of the antioxidant effects of biophenolic compounds is supported by the current interest in natural products and the ongoing replacement of synthetic antioxidants by natural antioxidants from plant sources. Olives and olive oil, especially extra virgin olive oil, contain a variety of bioactive compounds (phytochemicals) widely considered to be potentially beneficial for health. This research was focused on evaluating the antioxidant activity of the enriched refined olive oil to discover a possible functional food application. Different concentrations of individual and combined phenolic compounds were added to the refined olive oil as lipid matrix, and the antioxidant activity expressed as oxidative stability in hours was determined by using the Rancimat method. Additionally, the bitter index was evaluated to assess the effect of the enrichment in relation to the organoleptic quality. The results showed that the antioxidant activity depends on the concentration of the phenol used for the assay and the chemical structure. In general, the most positive effects were observed in 3,4-dihydroxy and 3,4,5-trihydroxy structures linked to an aromatic ring that conferred to the moiety a higher proton dislocation, thus facilitating the scavenging activity.

At present it is widely accepted that there are at least two neurogenic sites in the adult mammalian brain: the subventricular zone (SVZ) of lateral ventricles and the subgranular zone (SGZ) of the hippocampus dentate gyrus. The adult proliferation rate declines with aging and is altered in several neurodegenerative pathologies including Alzheimer's disease. The aim of this work was to study whether a natural diet rich in polyphenols and polyunsaturated fatty acids (LMN diet) can modulate neurogenesis in adult mice and give insight into putative mechanisms. Results with BrdU and PCNA demonstrated that the LMN fed mice had more newly generated cells in the SVZ and SGZ, and those with DCX (undifferentiated neurons) and tyrosine hydroxylase, calretinin, and calbindin (differentiated neurons) immunostainings and western blots demonstrated a significant effect on neuronal populations, strongly supporting a positive role of the LMN diet on adult neurogenesis. In primary rat neuron cultures, the LMN cream dramatically protected against damage caused by both hydrogen peroxide and Abeta(1-42), demonstrating a potent antioxidant effect that could play a major role in the normal adult neurogenesis and, moreover, the LMN diet could have a significant effect combating the cognitive function decline during both aging and neurodegenerative diseases such as Alzheimer's disease.

The formulation of a product enriched or fortified with procyanidins is a way to increase their bioavailability, with clear effects on the plasmatic pharmacokinetics, and a greater accumulation of phenolic metabolites in such tissues as the liver, kidney, lung and brain.

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Human bioavailability of cocoa flavanols and phenolic acids from a cocoa-nut cream (CC) and from CC enriched with a 1·5 % (w/w) cocoa polyphenol extract in free form (FPC) or encapsulated with a gastric-resistant high-amylose maize starch (EPC), was studied. In a randomised cross-over protocol, with 1-week wash-out in between, twelve healthy volunteers had three portions/d of each cream, providing approximately 190 mmol/d of total flavanols and 12 mmol/d of total phenolic acids with CC and 385 and 28 mmol/d with both FPC and EPC, respectively. Blood, urine and faecal samples were analysed by HPLC/MS/MS. Serum (epi)catechin was absent at baseline and after CC consumption, while 22·1 (SEM 2·62) and 1·59 (SEM 0·22) nmol (P , 0·05) were found after FPC and EPC, respectively. The EPC increased faecal excretion of total flavanols compared to FPC (151·0 (SEM 54·6) v. 28·0 (SEM 14·0) nmol; P , 0·05). Within 6 h after consumption, serum phenolic acid content was 50-fold higher than (epi)catechin; no difference between CC and FPC was observed, but a significant reduction after EPC (1954 (SEM 236·3) and 1459 (SEM 137·6) v. 726·8 (SEM 73·4) nmol, P , 0·05) was recorded. Short-term phenolic acid urinary excretions were significantly higher after FPC than CC and EPC, the values being 11·4 (SEM 5·1) v. 3·1 (SEM 1·7) and 0·9 (SEM 0·5) mmol, respectively. Faecal phenolic acids were approximately 60-fold reduced after FPC (8·1 (SEM 0·13) nmol) and EPC (14·7 (SEM 2·7) nmol) consumption compared to CC (641·4 (SEM 99·1) nmol) consumption. The data demonstrated that: (i) (epi)catechin was absorbed from CC; (ii) cocoa polyphenols' consumption increased circulating phenolic acids; and (iii) encapsulated ingredient increased flavanol delivering into the gut. Further studies should evaluate whether encapsulated cocoa polyphenols may be a functional prebiotic ingredient.