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This work describes the applicability of an in vitro digestion model for the evaluation of the digestibility and bioaccessibility of cocoa polyphenols (procyanidins, phenolic acids, and flavones) and for the study of the food matrix effect in relation with the fat content. For this purpose, two cocoa samples, cocoa liquor ( approximately 50% fat content) and cocoa powder ( approximately 15% fat content), were used. The results showed an important increase of the concentration of procyanidin (monomers and dimers), probably due to the hydrolysis of procyanidins with a high degree of polymerization (pentamers to nonamers) submitted to the digestion procedure. In relation to flavones, the concentration of aglycone forms remained almost constant after the digestion steps; in contrast, the concentration of the glycoside forms an increase in the digestion mixtures mainly after the duodenal step, probably as a result of the partial digestion of the dietary fiber present in the cocoa. The higher fat content in the cocoa liquor seemed to have a protective effect, probably related with a better micellarization that favors the stability of polyphenols during digestion.

The aim of this study was to evaluate several cocoa sources to obtain a rich phenol extract for use as an ingredient in the food industry. Two types of phenolic extracts, complete and purified, from different cocoa sources (beans, nibs, liquor, and cocoa powder) were investigated. UPLC-MS/MS was used to identify and quantify the phenolic composition of the extracts, and the Folin-Ciocalteu and vanillin assays were used to determine the total phenolic and flavan-3-ol contents, respectively. The DPPH and ORAC assays were used to measure their antioxidant activity. The results of the analysis of the composition of the extracts revealed that the major fraction was procyanidins, followed by flavones and phenolic acids. From the obtained results, the nib could be considered the most interesting source for obtaining a rich phenolic cocoa extract because of its rich phenolic profile content and high antioxidant activity in comparison with the other cocoa sources.

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.