Instituto Nacional Of Investigacao Agraria

Lisbon, Portugal

Instituto Nacional Of Investigacao Agraria

Lisbon, Portugal
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Baptista M.,New University of Lisbon | Baptista M.,Instituto Nacional Of Investigacao Agraria | Antunes F.,University of Lisbon | Goncalves M.S.,Instituto Nacional Of Investigacao Agraria | And 2 more authors.
Waste Management | Year: 2010

This study focuses on the investigation of the kinetics of municipal solid waste composting in three full-scale mechanical-biological treatment (MBT) plants. The aims were to test a kinetic model based on volatile solids (VS) content change for describing the composting process in MBT plants, and to identify the model parameters that affected the estimation of the reaction rate constant most. To achieve this, VS content and several environmental conditions, namely temperature, moisture content, oxygen concentration and total bulk density were monitored throughout the composting process. Experimental data was fitted with a first-order kinetic model, and a rate constant (k) characteristic of composting under optimum environmental conditions was obtained. The kinetic model satisfactorily described the experimental data for the three MBT plants. k values ranged from 0.043±0.002d-1 to 0.082±0.011d-1. Sensitivity analysis showed that the model parameters that most affected the estimation of k were the initial biodegradable volatile solids content, the maximum temperature for biodegradation and the optimum moisture content. In conclusion, we show for the first time that full-scale MBT plants can be successfully modelled with a composting kinetic model. © 2010 Elsevier Ltd.

Baptista M.,New University of Lisbon | Baptista M.,Instituto Nacional Of Investigacao Agraria | Antunes F.,University of Lisbon | Silveira A.,New University of Lisbon
Waste Management and Research | Year: 2011

The aims of this study were (i) to evaluate the performance of the composting process operation in full-scale mechanical-biological treatment (MBT) plants, (ii) to estimate their performance under optimized conditions and (iii) to propose specific guidelines on how to improve the efficiency of the composting process. To fulfil these objectives, a first-order kinetic model was used. This model was calibrated with experimental data to account for the limitations imposed by less-than-optimal environmental conditions during operation of the composting process. Data treatment and simulation showed that two of the three MBT plants studied were poorly operated. Optimization of process management with measures of simple practical implementation was estimated to be highly significant in these poorly managed plants, increasing performance by 103% in MBT1 and 53% in MBT2. In MBT3, the potential for optimization was estimated at 17%. Similar results were obtained from the analysis of other published data, suggesting that poor process management in MBT composting is widespread. These findings highlight the importance of having programmes for monitoring and optimizing process performance in full-scale composting systems. The procedures developed here are simple to apply and can routinely be implemented in full-scale plants. © The Author(s) 2011.

Baptista M.,New University of Lisbon | Baptista M.,Instituto Nacional Of Investigacao Agraria | Silveira A.,New University of Lisbon | Antunes F.,University of Lisbon
Waste Management and Research | Year: 2012

Composting research at laboratory-scale is critical for the development of optimized full-scale plants. Discrepancies between processes at laboratory-scale and full-scale systems have been investigated in terms of heat balances, but a kinetic analysis of this issue is still missing. In this study, the composting rate at laboratory-scale was, on average, between 1.9 and 5.7 times faster than in full-scale systems for a set of published studies using municipal solid waste, food waste or similar materials. Laboratory-scale performance and full-scale systems were limited to 71 and 46%, respectively, of their maximum potential due to poor management of environmental process conditions far from their optimum. The main limiting environmental factor was found to be moisture content, followed by temperature. Besides environmental factors, waste composition and particle size were identified as factors accounting for kinetic differences between laboratory- and full-scale systems. Overall, this study identifies those factors that affect the kinetics of the composting process most and revealed a significant margin for reducing process time in full-scale composting. © The Author(s) 2012.

Partelli F.L.,Federal University of Espirito Santo | Partelli F.L.,Instituto Investigacao Cientifica Tropical | Batista-Santos P.,Instituto Investigacao Cientifica Tropical | Scotti-Campos P.,Instituto Nacional Of Investigacao Agraria | And 5 more authors.
Environmental and Experimental Botany | Year: 2011

Low temperatures affect many plant physiological and biochemical components, amongst them the lipid phase of membranes. The present work aimed to characterize the lipid composition of chloroplast membranes of three Coffea genotypes, representing three agronomic valuable species (Coffea arabica cv. Icatu, Coffea canephora cv. Conilon clone 02 and Coffea dewevrei), under adequate environmental conditions and to relate its cold tolerance ability to the adjustments triggered during a gradual temperature decrease, after chilling exposure and upon a recovery period. Under adequate temperature (25/20 °C, day/night) the lipid composition of chloroplast membranes was fairly similar amongst the genotypes concerning the total fatty acid (TFA) content and individual FAs (both globally or within the classes), suggesting a close lipid composition amongst Coffea species, which can be considered as " C18:3" plants. Under cold exposure and subsequent recovery the genotypes undergo adjustments, some of them with acclimation potential. The genotypes displayed some ability to increase lipid synthesis, increasing their FA content. However, under cold exposure (even at 4 °C), Icatu and C. dewevrei plants performed qualitative adjustments, including preferential synthesis of phospholipids (especially PG) instead of galactolipids and increases in the unsaturation degree of DGDG and phospholipid classes (PG, PC and PI). Clone 02 maintained almost all lipid characteristics, what explains its higher cold sensitivity. Furthermore, differences that contribute to explain contrasting cold sensitivity in Icatu (more tolerant) and C. dewevrei emerged when analyzing PA content (taken as a stress metabolite) and the FA composition within MGDG and PG classes. C. dewevrei presented the higher increase, absolute value and relative weight of PA, while Icatu was the solely genotype to show a rise in the unsaturation degree of MGDG and PG, displaying as well the highest DBI values for these classes. We conclude that lipid qualitative and quantitative adjustments constitute a flexible mechanism that decisively contributes to cold acclimation in Coffea spp., working in tandem with others that minimize oxidative stress damages. © 2011 Elsevier B.V.

Cardoso S.,Institute Tecnologia Quimica e Biologica | Cardoso S.,University College London | Lau W.,University College London | Eiras Dias J.,Instituto Nacional Of Investigacao Agraria | And 2 more authors.
PLoS ONE | Year: 2014

Anthocyanin content is a trait of major interest in Vitis vinifera L. These compounds affect grape and wine quality, and have beneficial effects on human health. A candidate-gene approach was used to identify genetic variants associated with anthocyanin content in grape berries. A total of 445 polymorphisms were identified in 5 genes encoding transcription factors and 10 genes involved in either the biosynthetic pathway or transport of anthocyanins. A total of 124 SNPs were selected to examine association with a wide range of phenotypes based on RP-HPLC analysis and visual characterization. The phenotypes were total skin anthocyanin (TSA) concentration but also specific types of anthocyanins and relative abundance. The visual assessment was based on OIV (Organisation Internationale de la Vigne et du Vin) descriptors for berry and skin colour. The genes encoding the transcription factors MYB11, MYBCC and MYCB were significantly associated with TSA concentration. UFGT and MRP were associated with several different types of anthocyanins. Skin and pulp colour were associated with nine genes (MYB11, MYBCC, MYCB, UFGT, MRP, DFR, LDOX, CHI and GST). Pulp colour was associated with a similar group of 11 genes (MYB11, MYBCC, MYCB, MYCA, UFGT, MRP, GST, DFR, LDOX, CHI and CHSA). Statistical interactions were observed between SNPs within the transcription factors MYB11, MYBCC and MYCB. SNPs within LDOX interacted with MYB11 and MYCB, while SNPs within CHI interacted with MYB11 only. Together, these findings suggest the involvement of these genes in anthocyanin content and on the regulation of anthocyanin biosynthesis. This work forms a benchmark for replication and functional studies. © 2012 Cardoso et al.

Diogo E.L.F.,Instituto Nacional Of Investigacao Agraria | Santos J.M.,New University of Lisbon | Phillips A.J.L.,New University of Lisbon
Fungal Diversity | Year: 2010

The ascomycete genus Diaporthe includes plant pathogens and endophytes on a wide range of hosts including economically important crops. Anamorphs are coelomycetous and reside in the genus Phomopsis. Phomopsis amygdali is the causal agent of twig canker and blight of almonds. In a recent survey of dieback of almonds in Portugal, the most frequent fungi detected were Diaporthe/Phomopsis species. Isolates from almond and other Prunus species were characterised and grouped according to their microsatelliteprimed PCR (MSP-PCR) profiles and representatives of the different groups were selected for a phylogenetic study based on the ITS rDNA region (ITS1-5.8S-ITS2). Combining morphological, cultural, molecular and pathogenicity data, three species were distinguished. Phomopsis amygdali was shown to be the main pathogen on almond and is epitypified in the present work. Diaporthe neotheicola is reported for the first time on this host. A third species represented by a single isolate could not be unequivocally identified. © 2010 Kevin D. Hyde.

Gouvinhas I.,Royal University | Machado N.,Royal University | Carvalho T.,Instituto Nacional Of Investigacao Agraria | De Almeida J.M.M.M.,Royal University | And 2 more authors.
Talanta | Year: 2015

Extra virgin olive oils produced from three cultivars on different maturation stages were characterized using Raman spectroscopy. Chemometric methods (principal component analysis, discriminant analysis, principal component regression and partial least squares regression) applied to Raman spectral data were utilized to evaluate and quantify the statistical differences between cultivars and their ripening process. The models for predicting the peroxide value and free acidity of olive oils showed good calibration and prediction values and presented high coefficients of determination (>0.933). Both the R2, and the correlation equations between the measured chemical parameters, and the values predicted by each approach are presented; these comprehend both PCR and PLS, used to assess SNV normalized Raman data, as well as first and second derivative of the spectra. This study demonstrates that a combination of Raman spectroscopy with multivariate analysis methods can be useful to predict rapidly olive oil chemical characteristics during the maturation process. © 2014 Elsevier B.V.

Palha M.G.,Instituto Nacional Of Investigacao Agraria | Campo J.L.,Instituto Nacional Of Investigacao Agraria | Oliveira P.B.,Instituto Nacional Of Investigacao Agraria
Acta Horticulturae | Year: 2012

Plant growth, flowering and dry matter partitioning of four cold stored strawberry plant types of cultivar 'Elsanta' were assessed at three planting dates, in an autumn production system. Tray plants had the highest initial total plant fresh weight, followed by waiting bed (WB) and A+ plants. The A plants had the smallest initial plant size. One month after planting, plants had an active period of growth, mainly of roots and leaves and less of crowns and flowers. Two months after planting, plant biomass allocation was mostly to leaves, flowers and fruits, this effect being more significant for the first planting date. All plant material types showed similar trends in dry matter partitioning throughout the season. Earlier planting dates induced plants to accumulate more biomass. The highest dry-matter accumulation was observed in tray plants, followed by WB and A+ plants, which also reflected the higher crown number, leaf area, inflorescence and flower number produced by those plant types. The A plants showed the lowest vegetative and flowering response. These results indicate that the initial size of planting material affects growth and flowering of 'Elsanta' during autumn season production, with earlier planting dates, inducing higher plant biomass accumulation.

De Oliveira P.B.,Instituto Nacional Of Investigacao Agraria | Dale A.,University of Guelph
Journal of Berry Research | Year: 2012

Corema album (Ericaceae), 'Camarinhas', or the 'white crowberry', is a white-berried perennial adapted to sandy soils in the Iberian Peninsula which has been consumed by humans for many centuries. It occurs naturally on sand dunes and cliffs of the Atlantic coast from Gibraltar to Finisterre, and in the Azores on volcanic lava and ash fields. It has the possibility to become a new niche berry crop, because its fruits have a distinct colour (white), and provide high nutritional value. It has the potential to spread throughout southern Europe and the Mediterranean basin. The round, white, berry-like drupes (0.3-0.5 g), have a strong skin, and usually have three large seeds with a thick endocarp. The fruits can be marketable after five days at room temperature, and some samples have been acceptable after five months at 4°C. Here, the taxonomy, biology, and potential production system are discussed and a potential marketing name, the Beachberry, introduced. © 2012 - IOS Press and the authors. All rights reserved.

Souza X.R.,IFMT Campus Sao Vicente | Faria P.B.,Federal University of Lavras | Bressan M.C.,Instituto Nacional Of Investigacao Agraria
Revista Brasileira de Ciencia Avicola | Year: 2011

In this study, the physical-chemical characteristics and proximate composition of the meat of of two strains of broilers (Paraíso Pedrês and Máster gris plumé - Super Pesadão, utilized for semi-intensive rearing) and Cobb® strain, utilized in intensive rearing systems) were evaluated. Differences related to strain and sex (males and females) were studied. Cobb® broilers were slaughtered at 45 days and the other strains at 85 days. The following characteristics were evaluated in breast and thigh meat: moisture, protein, ether extract, ashes, color (CIEL*a*b*), final pH, cooking loss (CL) and shear force (SF). Bird strain and sex influenced breast color parameters, with Cobb® presenting higher yellowness (b*) and redness (a*) means, whereas females had higher b* values and males, a* values. Paraíso Pedrês had lower SF values. As to proximate composition, there was an interaction between strain and sex, with higher ether extract values in the meat of Super Pesadão males. Cobb® birds presented higher lightness (L*) and b* values, and there was no effect of sex on color parameters. Higher pH and SF values were found in the meat of Super Pesadão birds. There was an interaction between strain and sex for b* and SF values, with higher b* values obtained with Cobb® males, while differences between sex, with superiority for females in the Paraíso Pedrês strain and for males in the Cobb® strain were found. Increased values of SF for males were obtained for Super Pesadão strain. Both Paraíso Pedrês and Super Pesadão strains presented physicochemical and proximate composition characteristics similar to those of Cobb® strain in the cuts breast and thigh so that in a few parameters, no differences between the birds kept in this two rearing systems were found.

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