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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]

Grapevine leaves ( Vitis vinifera L. var. Malvasia Fina and Touriga Franca) under culinary treatment (blanching and boiling at 60, 75 and 90 min) were studied for their color, pigments and volatile fraction changes. Blanching and boiling caused a decrease in luminosity and a loss of green coloration in both varieties, while a yellow-brownish color arose. Significant correlations were established between the loss of green color (monochromatic variable a ∗ ) and the total chlorophylls content. The main volatiles in fresh leaves [( Z )-3-hexenal, ( Z )-3-hexen-1-ol, and ( Z )-3-hexenyl acetate] were drastically reduced by blanching and suppressed by boiling. Other compounds like pentanal and 6-methyl-5-hepten-2 one arose from blanching and boiling. A boiling time of 60 min is adequate for the culinary process of grapevine leaves, since the product is considered edible and the pigments and volatile changes are not as drastic as observed at 75 and 90 min of boiling. [ABSTRACT FROM AUTHOR]

Production of virgin olive oil is beginning in Brazil. This paper analyzes the characteristics of the EVOO Arbequina from Brazil in comparison with Spanish Arbequina from different regions. Quality parameters, oxidative stability, pigments, colour and fatty acid profile were assessed, and relationships with geographic and climatic conditions were studied. All the samples presented good quality and met EU standards for extra-virgin olive oil, but there were significant differences between regions and countries for many of the parameters evaluated. Major differences between Brazilian and Spanish samples were observed for free acidity and colour of the oils, as well as minor variations in the fatty acid profile. The colour differences were related to rainfall, whereas the fatty acid content was strongly influenced by altitude and temperature. These results highlight the fact that geographic area and environmental factors influence the characteristics of Arbequina oil and play an important role in newly introduced cultivars. [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]

Araniella cucurbitina (Araneae: Araneidae) is a widespread orb-weaver spider commonly found in agroecosystems. Mineral particle films such as kaolin, due to their protective or anti-feeding action, can represent an alternative to pesticides, especially in organic farming systems, but little is known about its effects on A. cucurbitina . Therefore, we tested the effect of kaolin sprays on the life span of A. cucurbitina under laboratory conditions. Four treatments were tested encompassing different exposure routes. Thus, kaolin sprays were applied on (i) the surface, (ii) the prey (fly), (iii) the spider and (iv) both spider & prey. A control group was tested with water in each treatment. Results showed that sprays of kaolin significantly affected the survival of A. curcubitina when applications were done on the surface and on both spider & prey registering a reduction of 48% and 56%, respectively. Spiders in control obtained higher probability of reaching alive at the end of the assay than those treated with kaolin. Differences observed can be explained by the feeding behavior of the species and may depend on the consumption of the web by the spider and the ratio spider/fly for body size. [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]

Abstract: Table olives are a traditional component of the Mediterranean diet and are largely consumed in the world. There are different trade treatments that originate different types of olives. The aim of the present work was to proceed to the microbiological characterization of table olives commercialized in the Portuguese market, with respect to their microbiological safety. The microbiological characterization was made in the olive pulp and packing brine of thirty-five table olives samples of different types and trade treatments, namely natural olives Cv. Galega (NOG), natural turning colour olives (NTCO), green olives (GO), black ripe olives (BO) and natural olives purchased in the traditional market and obtained from traditional producers (NOt). Simultaneously it was verified specific legislation of the table olives in what it concerns to labeling rules, pH values and the identification of isolated yeasts. In general, table olives consumed showed acceptable security with exception of four NOt samples that presented Staphylococcus aureus. In a considerable number of samples high number of microorganisms indicators of contaminations were observed that reveals the need of optimization the hygienic procedures during production process to improve the quality and safety of table olives. During the work seven yeasts were isolated from olive pulp and brine. [Copyright &y& Elsevier]

Abstract: The chemical composition, antioxidant potential and antimicrobial activity were studied in six walnuts (Juglans regia L.) cultivars (cv. Franquette, Lara, Marbot, Mayette, Mellanaise and Parisienne) produced in Portugal. Concerning their chemical composition the main constituent of fruits was fat ranging from 78.83% to 82.14%, being the nutritional value around 720kcal per 100g of fruits. Linoleic acid was the major fatty acid reaching the maximum value of 60.30% (cv. Lara) followed by oleic, linolenic and palmitic acids. The aqueous extracts of walnut cultivars were investigated by the reducing power assay, the scavenging effect on DPPH (2,2-diphenyl-1-picrylhydrazyl) radicals and β-carotene linoleate model system. All the walnut extracts exhibited antioxidant capacity in a concentration-dependent manner being the lowest EC50 values obtained with extracts of cv. Parisienne. Their antimicrobial capacity was also checked against gram positive (Bacillus cereus, Bacillus subtilis, Staphylococcus aureus) and gram negative bacteria (Pseudomonas aeruginosa, Escherichia coli, Klebsiella pneumoniae) and fungi (Candida albicans, Cryptococcus neoformans), revealing activity against the different tested microorganisms. [Copyright &y& Elsevier]

Abstract: Different cultivars of walnut (Juglans regia L.) leaves (Cv. Lara, Franquette, Mayette, Marbot, Mellanaise and Parisienne) grown in Portugal, were investigated in what concerns phenolic compounds and antimicrobial and antioxidant properties. Phenolics analysis was performed by reversed-phase HPLC/DAD and 10 compounds were identified and quantified: 3- and 5-caffeoylquinic acids, 3- and 4-p-coumaroylquinic acids, p-coumaric acid, quercetin 3-galactoside, quercetin 3-pentoside derivative, quercetin 3-arabinoside, quercetin 3-xyloside and quercetin 3-rhamnoside. The antimicrobial capacity was screened against Gram positive (Bacillus cereus, B. subtilis, Staphylococcus aureus) and Gram negative bacteria (Pseudomonas aeruginosa, Escherichia coli, Klebsiella pneumoniae) and fungi (Candida albicans, Cryptococcus neoformans). Walnut leaves selectively inhibited the growth of Gram positive bacteria, being B. cereus the most susceptible one (MIC 0.1mg/mL). Gram negative bacteria and fungi were resistant to the extracts at 100mg/mL. Lara walnut leaves were also submitted to antibacterial assays using 18 clinical isolates of Staphylococcus sp. Antioxidant activity was accessed by the reducing power assay, the scavenging effect on DPPH (2,2-diphenyl-1-picrylhydrazyl) radicals and β-carotene linoleate model system. In a general way, all of the studied walnut leaves cultivars presented high antioxidant activity (EC50 values lower than 1mg/mL), being Cv. Lara the most effective one. [Copyright &y& Elsevier]

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]

Flavouring and fortifying virgin olive oils is an increasing commercial trend, aiming to meet new consumers' preferences and provide new differentiated products. These practices usually positively impact the oils' sensory profile and chemical composition, increasing their natural richness on bioactive compounds. However, some negative effects have also been reported. This review provides a summary of common flavouring/fortification techniques as well as of the usual natural agents used. Co-extraction, contact and essential oils incorporation techniques are addressed. Usually, flavouring/fortification enhances desirable sensory sensations, and shelf-life, and promotes the incorporation of bioactive compounds like antioxidants. Also, the excess of flavouring may promote the appearance of unpleasant sensory sensations and, in some cases, results in pro-oxidant activity. Fortification, in turn, involves the incorporation of extracts rich in bioactive compounds, contributing to the nutritional and healthy enrichment of the olive oil. However, fortification may also increase the oil's turbidity and/or promote the appearance of unpleasant sensory sensations, resulting in a less appealing oil, hindering the consumers' purchasing. Although traditional in the Mediterranean, olive oil flavouring or fortification may have positive/negative effects at chemical and sensory levels. This awareness is of paramount commercial importance and can be used as a decision-maker tool for olive oil producers. Thus, the advantages/disadvantages of the different methodologies are discussed, and some perspectives and possible future directions are proposed and briefly discussed. • Olive oil flavouring is a traditional practice in the Mediterranean region. • Aromatic plants, fruits, spices and olive tree leaves are the usual flavouring agents. • Flavouring by contact and co-extraction are the most common techniques. • Flavouring and/or fortification aims to enhance the olive oil overall quality. • Positive and negative effects on the oils chemical-sensory quality are reported. [ABSTRACT FROM AUTHOR]

Abstract: Pollen analysis, total phenols content and antioxidant activity were studied for the first time in Portuguese propolis samples from Bornes and Fundão regions. Total phenols content was determined by colorimetric assay and their amount was of 329mg/g of GAE in Bornes sample and 151mg/g of GAE in Fundão propolis. The antioxidant capacity of propolis extracts was assessed through the scavenging effects on DPPH (2,2-diphenyl-1-picrylhydrazyl) and reducing power of iron (III)/ ferricyanide complex assays. A concentration-dependent antioxidative capacity was verified in DPPH and reducing power assays. Low values of EC50 on DPPH scavenging assay were obtained for Bornes and Fundão propolis (of 6.22μg/mL and 52.00μg/mL, respectively). For reducing power the values were 9.00μg/mL, for Bornes propolis, and 55.00μg/mL, for Fundão propolis. The high activity of propolis from Bornes could be related with their different pollen composition. The results obtained indicate that Portuguese propolis is an important source of total phenols showing antioxidant properties that could be beneficial for human health. [Copyright &y& Elsevier]

Abstract: Soil arthropod biodiversity is an indicator of soil quality and can be studied using pitfall trapping. In this research, olive grove edaphic fauna was assessed at different sampling dates by comparing two different diameters (7 and 9cm) and three different contents (empty, water and preservative) of pitfall traps in order to determine which type of pitfall trap is more efficient. Considering all pitfall trap types and sampling times, a total of 12,937 individual edaphic arthropods belonging to 11 taxa were recovered. Smaller traps with preservative collected significantly more individuals than the other pitfalls tested. Larger and empty traps collected significantly more spiders and traps with preservative collected more beetles. Smaller and empty traps collected fewer individuals than the other trap types. Both Shannon''s diversity and Pielou''s evenness indexes were higher in the larger and empty traps and richness was higher in the smaller traps filled with water. The study of myrmecocenosis was emphasised because olive grove soil fauna was numerically dominated by Formicidae (56.6% of all organisms captured) belonging to 12 genera and 24 species; Tapinoma nigerrimum, Messor barbarus, Cataglyphis hispanicus, Tetramorium semilaeve, Cataglyphis ibericus, Messor bouvieri and Camponotus cruentatus were the most abundant ant species. Traps with preservative reached the highest accumulation of species for a small number of pitfalls when compared with the other pitfalls studied and a sampling effort of 20 samples is apparently sufficient to sample the greater part of the ant species of the olive grove. From this study, it seems that traps with preservative are the best choice to use in further studies concerning the epiedaphic fauna of the olive grove. [Copyright &y& Elsevier]

• Significant differences in flowers' compositions were observed. • Water was the main macronutrient, followed by carbohydrates and total dietary fiber. • α-Tocopherol and lutein were the major components with regard to vitamin E and carotenoids. • Malic acid was the major organic acid, except in centaurea. • Fructose, glucose and sucrose were detected in all flowers. The present study aimed to evaluate the nutritional and bioactive potential of four edible flowers (borage, centaurea, camellia, and pansies). Significant differences were observed among the four. Water was the main constituent (>76%, fresh weight - fw). Linoleic and palmitic acids were the major fatty acids found in borage and red and yellow pansies, while in camellia it was the arachidic acid. In white pansies, behenic and arachidic acids were predominant. Concerning vitamin E, α-tocopherol was the major vitamer. Carotenoids values varied between 5.8 and 181.4 mg β-carotene/100 g dry weight (dw) in centaurea and borage, respectively, being particularly rich in lutein. Malic acid was the major organic acid, except in centaurea, where succinic acid was predominant. Fructose, glucose and sucrose were detected in all flowers. These results can contribute to the knowledge of these edible flowers and consequently increase their popularity among consumers and in the food industry. [ABSTRACT FROM AUTHOR]

Highlights • Olive oil phenolics from centenarian trees were evaluated during 4 harvest seasons. • Statistical analysis discriminate olive oils by total phenols levels. • Half of the specimens produced oils that were able to consistently fulfill olive oils' health claim. • Some trees gave high phenolic contents being potential candidates for breeding. • Individual phenolic contents separate olive oils by crop year. Abstract Olive oil phenolic compounds are receiving increased attention due to its influence on sensory characteristics and to scientific evidences of positive health effects. In this work, 28 ancient olive trees were selected and, during four consecutive seasons (2014–2017), oils were extracted and their phenolic fraction characterized. Hydroxytyrosol and tyrosol secoiridoids were the predominant groups, with contents between 32 and 496 mg of tyrosol equivalents/kg. Based on principal component analysis it could be concluded that the individual phenolic contents enabled the unsupervised grouping of olive oils by crop year. Furthermore, linear discriminant analysis allowed achieving sensitivities greater than 90%. It was shown that some specimens consistently allowed obtaining oils with high phenolic contents (≥500 mg tyrosol equivalents/kg). The identification of centenarian specimens for breeding based on their potential to produce oils with high levels of healthy compounds is of utmost interest, contributing to preserve the genetic heritage. [ABSTRACT FROM AUTHOR]

This study focused on the volatile changes in cv. Verdeal Transmontana throughout the entire olive oil processing chain, from the drupe to olive oil storage up to 12 months, while correlating it with quality parameters and sensory quality. During crushing and malaxation, the volatiles formed were mainly “green-leaf volatiles” (GLVs), namely ( E )-2-hexenal, hexanal, and 1-hexanol. Centrifugation and clarification steps increased the total volatile amounts to 130 mg kg −1 . However, clarification also increased nonanal and ( E )-2-decenal contents, two markers of oxidation, with a noticeable loss of phenolic compounds and oxidative stability. During storage, the total volatile amounts reduced drastically (94% at 12 months after extraction), together with the positive sensory attributes fruity, green, bitter, and pungent. Despite being classified as extra-virgin after one year of storage, peroxides and conjugated dienes were significantly higher while there was a reduction in antioxidant capacity as well as in phenolic compounds (less 50%) and oxidative stability (57%). The present work allowed concluding that the extraction process modulates the volatile composition of olive oil, with a concentration of volatiles at the clarification step. During storage, volatiles are lost, mainly eight months after extraction, leading to the loss of important sensory attributes. [ABSTRACT FROM AUTHOR]

The olive fly, Bactrocera oleae (Rossi), is a monophagous pest that displays an oviposition preference among cultivars of olive ( Olea europaea L.). To clarify the oviposition preference, the olive leaf volatiles of three olive cultivars (Cobrançosa, Madural and Verdeal Transmontana) were assessed by headspace solid-phase microextraction gas chromatography–mass spectrometry (HS-SPME-GC/MS) at six different periods of olive fruit maturation and degrees of infestation. A total of 39 volatiles were identified, mainly esters and alcohols, with a minor percentage of aldehydes, ketones and terpenic compounds, including sesquiterpenes. At sampling dates with higher degrees of infestation, cv. Cobrançosa had, simultaneously, significantly lower infestation degrees and higher volatile amounts than the other two cultivars, with a probable deterrent effect for oviposition. The green leaf volatiles (GLVs) ( Z )-3-hexen-1-ol and ( Z )-3-hexen-1-ol acetate) were the main compounds identified in all cultivars, together with toluene. The abundance of GLVs decreased significantly throughout maturation, without significant differences among cultivars, while toluene showed a general increase and positive correlation with olive fly infestation levels. The results obtained could broaden our understanding of the roles of various types and amounts of olive volatiles in the environment, especially in olive fly host selection and cultivar preference. [ABSTRACT FROM AUTHOR]

Olive products are premium food products. Their inherent chemical composition and sensory attributes make them highly appreciated worldwide. Olive products quality and composition are severely compromised by diversified agricultural and technological factors, among which olive pests play a key factor, particularly the olive fly Bactrocera oleae (Rossi) (Diptera: Tephritidae). This pest reveals cultivar oviposition preference being the cause of severe economic damages caused each year. Losses goes from the field and tree to consumers table. The damages caused by olive fly, seen by an economic perspective, as well as their influence in olive products classification, quality, composition, stability, nutritional, bioactive and functional properties are discussed in the present revision. [ABSTRACT FROM AUTHOR]

Spent coffee grounds (SCG) represent a high-volume food waste worldwide, and several reuse approaches have been attempted. Herein, a greenhouse field experiment was carried out by cultivating Batavia lettuce with 5%, 10%, 15%, 20% and 30% (v/v) espresso SCG directly composted in the soil. Healthy vegetables were obtained for all treatments, without yield loss for up to 10% SCG. A progressive increment of green color intensity with increasing SCG content was observed, corroborated by the increase of their photosynthetic pigments (chlorophylls and carotenoids). Furthermore, total ascorbic acid and tocopherols showed statistical significant increases ( p < 0.001) between control and all tested groups. Marked variations of nutritionally relevant minerals, particularly potassium, phosphorous and sodium were also revealed at higher percentage treatments (20% and 30%). This approach constitutes a clean, direct, simple and cost-effective measure to produce value-added vegetables, while reducing food waste disposal. [ABSTRACT FROM AUTHOR]

Humans are not capable of synthesizing carotenoids de novo and thus, their presence in human tissues is entirely of dietary origin. Consumption of essential carotenoids is reduced due to the lower intake of fruits and vegetables. Microalgae are a good source of carotenoids that can be exploited. In the present work, carotenoids rich extracts from Scenedesmus almeriensis were added to extra-virgin olive oils at different concentrations (0.1 and 0.21 mg/mL) in order to enhance the consumption of these bioactives. Extracts brought changes in olive oils color, turning them orange-reddish. Quality of olive oils was improved, since peroxidation was inhibited. Olive oils fatty acids and tocopherols were not affected. β-carotene and lutein contents increase considerably, as well as oxidative stability, improving olive oils shelf-life and nutritional value. Inclusion of S. almeriensis extracts is a good strategy to improve and enhance the consumption of carotenoids, since olive oil consumption is increasing. [ABSTRACT FROM AUTHOR]