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A physiological approach to assessing the antioxidant potential of Arbequina EVOO from different zones of Brazil and Spain was performed, applying a combined model of simulated digestion and cell cultures, using the Caco-2 cell line. Our results showed an increasing of total phenolic content (TPC) and antioxidant properties promoted by the in vitro digestion. Preincubating Caco-2 cells with bioaccessible fractions of oils counteracted the cytotoxic effect promoted by an oxidising agent ( t -BOOH), preserving cell viability and reducing the generation of reactive oxygen species (ROS). The protective effect on ROS production was associated with the antioxidant activity (DPPH assay), but no relation with the TPC of the digested samples was found. Differences in the parameters evaluated were observed among the samples, which were related to climatic characteristics of the production zones. It was concluded that transformations during the digestive process are important for establishing the antioxidant potential of the oils. [ABSTRACT FROM AUTHOR]

Studies comparing fungal endophytes between above- and belowground woody crop organs and the factors that may structure their communities are lacking. Due to its great impact on the Mediterranean Basin, the olive tree was chosen for the isolation of endophytic fungi from roots, leaves and twigs in two seasons in north-eastern Portugal. Nine hundred seventy-six isolates belonging to 38 fungal species were obtained. Phomopsis columnaris , Fusarium oxysporum and Trichoderma gamsii were the most frequently isolated, collectively representing 69% of the isolates. Fungal diversity in the roots was higher than in the aboveground organs and higher in spring than autumn. Endophyte community similarity between the above- and belowground organs and between seasons was low. Species composition also varied spatially, with the fungal composition of the roots varying more among locations than that of the aboveground organs. Our results suggest olive tree endophyte community structure is affected by plant organ, location and season. [ABSTRACT FROM AUTHOR]

Maturation stage is a critical feature to obtain high quality olive products, with maximized bioactivity. In this study, phenolic composition and antioxidant activity of Cv . Cobrançosa through the maturation process were evaluated. The phenolic profile was assessed by HPLC/DAD, and antioxidant activity was studied through its reducing power and free-radical scavenging activity. Total phenols varied from 34 to 1 g/kg, respectively, in the first and last sampling dates. Oleuropein, the main phenolic in the first stages of maturation, decreased drastically during ripening. At intermediate and high maturation stages hydroxytyrosol was the predominant phenol. Globally, the reducing capacity of Cv. Cobrançosa olive fruits decreased during the maturation process but its radical scavenging activity was only slightly altered. A principal components analysis corroborated the characteristic phenolic profile and changes experienced by the olive fruit during the maturation process. These results are important to maximize Cv. Cobrançosa olive products' quality and biological properties. [ABSTRACT FROM AUTHOR]

The factors shaping endophytic fungal assemblages in reproductive organs have been less evaluated than in vegetative organs. Here, the temporal dynamics of fungal endophytes in inflorescences and fruits of olive tree cultivars with contrasting anthracnose susceptibilities was assessed, starting before flowers open until fruit ripening. Fungal diversity assessed by rRNA sequencing of cultivable isolates revealed a higher richness and abundance of endophytes in inflorescences than in fruits. Endophytes from Sordariomycetes were dominant in inflorescences, while in fruits they were from Dothideomycetes. The overall assemblages of inflorescences and fruits were shaped mainly by the plant organ, followed by the phenological stage and lastly, by the plant cultivar. The importance of cultivar as a shaping factor varied according to the plant organ, being only significant in inflorescence-associated endophytes. A set of fungal taxa were positively associated with a particular cultivar and phenological stage, likely contributing to the plant anthracnose resistance. • Temporal dynamic of fungal endophytes in inflorescences and fruits was studied. • Plant organ and phenological stage explain the fungal endophyte assemblage. • Plant genotype importance as a shaping factor changes according to the plant organ. • Host and phenological specificity for some fungal taxa were found. • Potential impact to plant disease resistance due to endophytic changes is discussed. [ABSTRACT FROM AUTHOR]