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Oeiras, Portugal

Goncalves D.M.,University of Lisbon | Oliveira C.M.,University of Lisbon | Oliveira P.B.,INIAV
Acta Horticulturae | Year: 2016

Considering the increased consumer interest in fresh blackberries (Rubus spp.), fruit must be available in supermarket shelves all year round. This encourages offseason production in Portugal, mainly from September to December. Growers use long canes in order to harvest fruit during this period. Considering the extension of the vegetative growth cycle in mild winter climates, cane management is difficult due to excessive vegetative vigor. A trial was setup in order to evaluate the possibility of utilizing this excessive vigor for a double cropping system in blackberry. In nonheated greenhouses, nine blackberry cultivars of different types were evaluated for their suitability for double cropping in early spring (soil) and late autumn (substrate). For each cultivar, two floricane suppression treatments (cutting and no cutting) were applied at the beginning of spring 2011. Four rooting treatments, including tip layering, tip layering followed by cold storage for 15 days after detachment from the stock plant, tip layering using 20-cm tipped primocanes, and simple layering, were also tested during summer 2011. Plants grown without floricanes produced longer primocanes and more nodes per primocane but had smaller cane diameters. Long canes were obtained from each cultivar, except 'Logan Thornless'. In December, one cultivar for each blackberry type was cold-stored from January to June 2012 and then cropped in non-heated tunnels, where they produced fruit from late August to late October. Yields ranged from 0.8 to 4.6 kg plant-1 in the spring (all cultivars) and from 0.9 to 2.3 kg plant-1 in autumn ('Chester Thornless' and 'Olallie' only). The results indicated that double cropping may be economically possible in blackberry using certain cultivars.

de Sousa M.B.,University of Lisbon | de Pinho M.N.,University of Lisbon | dos Santos P.C.,INIAV
Ciencia e Tecnica Vitivinicola | Year: 2014

This work addresses ultrafiltration of grape must and the understanding of the membrane/polysaccharides interactions due to the chemical composition of the soluble grape must polysaccharides. The performance of two laboratory-made cellulose acetate membranes was investigated. The membranes have molecular weight cut-off of 96 kDa (CA-400-32) and 31 kDa (CA-400-28). To identify the different polysaccharides in the fractions obtained by ultrafiltration, these molecules were isolated by dialysis, then concentrated, freeze-dried and the polysaccharide composition analysed by Gas-Chromatography with flame ionization detector after acid hydrolysis, reduction and acetylation. Polysaccharides adsorbed on the membranes were also identified and quantified by Gas-Chromatography, after hydrolysis, reduction and acetylation of the known mass of dehydrated membrane. The analysis of the membrane matrix, give evidence that mannoproteins were adsorbed on the matrix of CA-400-32 membrane, which has originated, in some extension, the clogging of the pores. It was concluded that the ramnogalacturonan type II crossed the CA-400-32 membrane easily, however its depletion in the retentate and permeate streams over time may be due to its accumulation on the membrane surface, probably caused by adsorption. Arabinogalactan-proteins and mannoproteins were found in the permeate stream of the CA- 400-32 membrane, whilst in the CA-400-28 membrane, ramnogalacturonan type II and the majority of arabinogalactan-proteins and mannoproteins remained in the retentate.

Peres C.M.,New University of Lisbon | Hernandez-Mendonza A.,New University of Lisbon | Hernandez-Mendonza A.,Research Center en Alimentacion y Desarrollo | Bronze M.R.,New University of Lisbon | And 5 more authors.
LWT - Food Science and Technology | Year: 2015

The increasing market of probiotics from plant matrices justifies the interest on fermented olives - not only for their nutritional properties, but also because they contain health-promoting phytochemicals (such as phenolic compounds) that exhibit antibacterial, antiproliferative, anticarcinogenic and antiinflammatory properties. Additionally, olives have proven a good source and carrier of Lactobacillus strains with probiotic characteristics. However, studies focusing on the combined effect of phenolic compounds with wild probiotic bacteria have not been yet carried out. Hence, the aim of this work was to set up the combination of native olive phenolic compounds, e.g. oleuropein and hydroxytyrosol, on the recommended levels for a daily dose of olives containing probiotic bacteria - and their effect on the attachment ability and action against pathogens in situ. Tests on the health benefits of these compounds, viability and adhesion capacity of probiotic bacteria, and consequent biofilm formation, composition and relationship with adhesivity on Caco-2 model were performed. The Caco-2 cell viability results (>140%) show that there is no toxicity effect of both phenolic compounds for the levels considered (0.04 and 0.01%, w/v, for OL and HT, respectively). Conversely, these compounds can inhibit (26e50%) proliferation of human colon adenocarcinoma cells. It became clear that biofilm production on abiotic surfaces is not necessarily associated with adhesivity on biotic surfaces. The strong increase in the adhesion degree of Lactobacillus plantarum 33 after biofilm establishment prompted evaluation of the correlation between biofilm formation and adhesion capacities. © 2015 Elsevier Ltd.

Peres C.M.,INIAV | Alves M.,New University of Lisbon | Hernandez-Mendoza A.,New University of Lisbon | Hernandez-Mendoza A.,Research Center en Alimentacion y Desarrollo | And 7 more authors.
LWT - Food Science and Technology | Year: 2014

The purpose of this work was to screen for and characterize the potential probiotic features of strains of lactic acid bacteria isolated from Galega cultivar fermented olives, to eventually develop an improved probiotic food from plant origin. From 156 isolated strains, 10 were acid - and bile salt tolerant, and exhibited survival rates up to 48%, following simulated digestion. All strains exhibited auto- (4-12%) and co-aggregation features (≥30%), as well as hydrophobicity (5-20%) and exopolysaccharide-producing abilities, while no strain possessed haemolytic capacity or ability to hydrolyse mucin. Antibiotic resistance, oleuropein degradation, proteolytic activity and antimicrobial activity were strain-dependent features. Overall, 10 strains - belonging to Lactobacillus plantarum and Lactobacillus paraplantarum, appear to possess a probiotic value. © 2014 Elsevier Ltd.

Gama L.T.,University of Lisbon | Martinez A.M.,University of Cordoba, Spain | Carolino I.,INIAV | Landi V.,University of Cordoba, Spain | And 6 more authors.
Genetics Selection Evolution | Year: 2013

Background: Native pig breeds in the Iberian Peninsula are broadly classified as belonging to either the Celtic or the Mediterranean breed groups, but there are other local populations that do not fit into any of these groups. Most of the native pig breeds in Iberia are in danger of extinction, and the assessment of their genetic diversity and population structure, relationships and possible admixture between breeds, and the appraisal of conservation alternatives are crucial to adopt appropriate management strategies. Methods. A panel of 24 microsatellite markers was used to genotype 844 animals representing the 17 most important native swine breeds and wild populations existing in Portugal and Spain and various statistical tools were applied to analyze the results. Results: Genetic diversity was high in the breeds studied, with an overall mean of 13.6 alleles per locus and an average expected heterozygosity of 0.80. Signs of genetic bottlenecks were observed in breeds with a small census size, and population substructure was present in some of the breeds with larger census sizes. Variability among breeds accounted for about 20% of the total genetic diversity, and was explained mostly by differences among the Celtic, Mediterranean and Basque breed groups, rather than by differences between domestic and wild pigs. Breeds clustered closely according to group, and proximity was detected between wild pigs and the Mediterranean cluster of breeds. Most breeds had their own structure and identity, with very little evidence of admixture, except for the Retinto and Entrepelado varieties of the Mediterranean group, which are very similar. Genetic influence of the identified breed clusters extends beyond the specific geographical areas across borders throughout the Iberian Peninsula, with a very sharp transition from one breed group to another. Analysis of conservation priorities confirms that the ranking of a breed for conservation depends on the emphasis placed on its contribution to the between- and within-breed components of genetic diversity. Conclusions: Native pig breeds in Iberia reveal high levels of genetic diversity, a solid breed structure and a clear organization in well-defined clusters. © 2013 Gama et al.; licensee BioMed Central Ltd.

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