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- Opuntia ficus indica waste as a cost effective carbon source for lactic acid production by Lactobacillus plantarumPublication . Derabli, Besma; Nancib, Aicha; Nancib, Nabil; Aníbal, Jaime; Raposo, Sara; Rodrigues, Brígida; Boudrant, JosephOpuntia ficus indica (OFI) waste was evaluated as a fermentation feedstock for lactic acid production using Lactobacillus plantarum. Dilute acid pretreatment of the OFI cladodes (OFIC) was performed for extracting maximum fermentable sugars by optimizing process parameters using statistical optimization method. The best results were obtained with HCl 1% (v/v), temperature 120 ◦C, residence time 40 min, granulation 350 μm and substrate loading 5% (w/v), the sugar concentration reached 24 g/L with low concentration of hydroxymethylfurfural. The feasibility of producing lactic acid from OFI fruit peel (OFIFP) as a source of carbon was also investigated. Lactobacillus plantarum was shown to have a capacity for lactic acid production from OFIC350 (granulation 350 μm) hydrolysate and OFIFP extract without detoxification. The highest lactic acid yields of 0.46 and 0.78 g/g were obtained from enzymatic hydrolysate of pretreated OFIC350 and OFIFP extract, respectively.
- Organic Maturation and Source-Rock Potential of the Mesozoic Algarve Basin: southern PortugalPublication . Fernandes, Paulo; Borges, Marisa; Rodrigues, B.; Matos, VascoThe Algarve Basin is an important Mesozoic depocentre in southern Portugal.
- Cost-effective bioethanol production at low content of nitrogen source from carob syrupPublication . Raposo, Sara; Sousa, Catarina; Rodrigues, B.; Lima-Costa, Maria Emília; Quintas, Célia; Rodrigues, F.Ethanol, as biofuel, has received great interest in the latest decades due to its potential as an alternative transport fuel. Nowadays, ethanol can be produced through fermentative processes, using sugar rich agricultural raw material and it may have a significant role in reducing environmental impact of fossil fuels.
- História térmica da bacia carbonífera de Moatize-MinjovaPublication . Fernandes, Paulo; Cogné, N.; Marques, J. M.; Rodrigues, B.; Jorge, R. C. G. S.; Jamal, D.Duas sondagens de prospecção de carvão executadas na Bacia Carbonífera de Moatize-Minjova, foram estudadas usando as técnicas do poder reflector da vitrinite e dos traços de fissão da apatite para avaliar a sua história térmica.
- Idades U-Pb de zircões detríticos do Grupo do Flysch do Baixo Alentejo, Zona Sul PortuguesaPublication . Rodrigues, B.; Chew, Dave; Jorge, R. C. G. S.; Fernandes, Paulo; Veiga-Pires, C.; Oliveira, J. T.Foram obtidas idades U-Pb através de ablação a lazer de zircões detríticos das formações do Grupo do Flysch do Baixo Alentejo. As idades obtidas sugerem uma proveniência sedimentar, no caso das formações de Mértola e Mira, com o envolvimento de uma componente detrítica intrabasinal (Zona Sul Portuguesa) e de áreas fontes associadas ao bordo sul da Zona da Ossa Morena. No caso da Formação de Brejeira as idades sugerem um envolvimento de áreas fontes correlacionáveis com o terreno Avalonia/Meguma assim como de sedimentos reciclados oriundos do Domínio Sul Português.
- Reply to Discussion on 'Detrital zircon geochronology of the Carboniferous Baixo Alentejo Flysch Group (South Portugal); constraints on the provenance and geodynamic evolution of the South Portuguese Zone', Journal of the Geological Society, 172, 294-308Publication . Rodrigues, B.; Chew, D. M.; Jorge, R. C. G. S.; Fernandes, Paulo; Veiga-Pires, C.; Oliveira, J. T.We would like to thank Pereira (2015) for his interest in our work and appreciate the opportunity to clarify some aspects of the Rodrigues et al. (2015) study. Here we dispute several fundamental assertions made in the discussion of our original paper. (1) Pereira (2015) states, based on the U–Pb detrital zircon data of Pereira et al. (2012a, 2014), that the turbidites of the Mértola (late Visean) and the Mira (Serpukhovian to early Bashkirian) formations of the Baixo Alentejo Flysch Group of the South Portuguese Zone (Fig. 1b), were ‘mainly derived from a source terrane dominated by zircon populations of Middle–Late Devonian ages (c. 393–359 Ma) that are absent in the Ossa–Morena Zone’ and that this detrital zircon population forms 37.7% of all detrital zircons of these two formations. However, a large population of zircons of Middle–Late Devonian age was not found in the Rodrigues et al. (2015) study. The Mértola Formation (sample FM1; table 1 of Rodrigues et al. 2015) is clearly dominated by one population whose zircon ages range between 388 and 326 Ma, with this group representing 68% of all ages obtained. This population shows a peak at 336 Ma (middle Visean).
- Biogas production from microalgal biomass produced in the tertiary treatment of urban wastewater: assessment of seasonal variationsPublication . Barros, Raúl; Raposo, Sara; Morais, Etiele; Rodrigues, Brígida; Lourenço Afonso, Valdemira; Gonçalves, Pedro; Marques, José; Cerqueira, Ricardo; Varela, João; Ribau Teixeira, Margarida; Barreira, LuísaThe valorization of microalgal biomass produced during wastewater treatment has the potential to mitigate treatment costs. As contaminated biomass (e.g., with pharmaceuticals, toxic metals, etc.) is often generated, biogas production is considered an effective valorization option. The biomass was obtained from a pilot facility of photobioreactors for tertiary wastewater treatment. The pilots were run for one year with naturally formed microalgal consortia. The biogas was generated in 70 mL crimp-top vials at 35 °C, quantified with a manometer and the methane yield measured by gas chromatography. A maximum biogas production of 311 mL/g volatile solids (VS) with a methane yield of 252 mL/g VS was obtained with the spring samples. These rather low values were not improved using previous thermo-acidic hydrolysis, suggesting that the low intrinsic biodegradable organic matter content of the consortia might be the cause for low yield. Considering the total volume of wastewater treated by this plant and the average amount of methane produced in this study, the substitution of the current tertiary treatment with the one here proposed would reduce the energy consumption of the plant by 20% and create an energy surplus of 2.8%. The implementation of this system would therefore contribute towards meeting the ambitious decarbonization targets established by the EU.
- Geochemistry and provenance of the Carboniferous Baixo Alentejo Flysch Group, South Portuguese ZonePublication . Jorge, R. C. G. S.; Fernandes, Paulo; Rodrigues, B.; Pereira, Zélia; Oliveira, José TomásThis work is focused on the turbiditic sediments from the Carboniferous Baixo Alentejo Flysch Group (BAFG) in the South Portuguese Zone, an external zone of the Iberian Variscides. The aim of this work is to constrain the provenance and tectonic setting of these sediments in a context of a complex evolution of SW Iberian Variscides. For this purpose, we performed a systematic study of petrographical and geochemical signatures of greywackes and shales from the three BAFG formations: Mértola, Mira and Brejeira. Major and trace element composition and ratios suggest heterogeneous source area composition for BAFG shales and greywackes. For the oldest Mértola Formation greywackes, source area is dominated by granitoid rocks with minor mafic input. The latter becomes residual in the Mira Formation. The youngest Brejeira Formation greywackes show clear felsic affiliation associated with an increase in recycled components. The shales of all three BAFG formations denote a granodioritic affiliation. Chemical Index of Alteration (CIA) and Plagioclase Index of Alteration (PIA) values suggest moderate weathering in the source areas of Mértola and Mira formations. These indices, together with A–CN–K relations, point out to steady-state weathering conditions in the source areas of both formations. In contrast, both CIA and PIA values for the Brejeira Formation indicate variable conditions of palaeoweathering, from moderate to intense, as a consequence of non-steady-state conditions probably triggered by tectonic instability in the provenance area. Compared to the greywackes, the shales of all three BAFG formations exhibit higher CIA and PIA values, as well as low K2O/Al2O3 (~0.2) and index of compositional variability (b1), reflecting the cumulative effect of multiple cycles of sedimentary recycling and prolonged chemical weathering history. Major and trace element distribution and upper continental crust-normalized multi-element plots suggest that the sediments of BAFG were derived mainly from a continental arc/active margin with minor contribution from old continental crust. Together, our geochemical data are compatible with BAFG sediments derived mainly from SW border of the Ossa Morena Zone (Gondwanan affinity), with possible contribution from an external (Avalonian) source.
- Bioethanol production using carob pod, as carbon source on submerged fermentationPublication . Lima-Costa, Maria Emília; Sousa, Catarina; Rodrigues, B.; Quintas, Célia; Raposo, SaraIn the latest years the research for new sources of carbon sources, among industry by-products as potential raw material for bioethanol production is a needful and a sustainable strategy for the success of 2nd generation biofuels.
- Comparative study of the antioxidant and enzyme inhibitory activities of two types of Moroccan Euphorbia entire honey and their phenolic extractsPublication . Boutoub, Oumaima; EL-GUENDOUZ, Soukaina; Manhita, Ana; Dias, Cristina Barrocas; Estevinho, Letícia M.; Paula, Vanessa B.; Carlier, Jorge; Costa, Maria Clara; Rodrigues, Brígida; Raposo, Sara; Aazza, Smail; El Ghadraoui, Lahsen; Miguel, Maria GraçaHoney is a natural food product very famous for its health benefits for being an important source of antioxidant and phenolic compounds. Euphorbia honeys obtained from different regions of Morocco were evaluated for their ability to inhibit acetylcholinesterase, lipoxygenase, tyrosinase and xanthine oxidase activities. Their antioxidant properties were evaluated using the: 2,2-diphenyl-1-picrylhydrazyl (DPPH) radical-scavenging capacity, nitric oxide scavenging activity (NO) and scavenging ability of superoxide anion radical. Then, the phenolic extracts of the same entire honey samples were evaluated by liquid chromatography coupled to diode array detection and mass spectrometry (LC-DAD-MS) and tested for the biological activities previously evaluated on the entire honeys, in order to conduct a comparative study between both (honey and phenolic extracts). The chromatographic profiles for the studied Euphorbia honey extracts were different. Phenolic compounds gallic acid, 4-hydroxybenzoic acid and p-coumaric acid were detected in all samples, whereas kampferol was only present in two samples. Physicochemical parameters and total phenolic content were also determined. Entire honey that recorded the highest rate of phenols was sample M6 (E. resinifera) = 69.25 mg GAE/100 g. On the other hand, the phenolic extracts had better antioxidant and enzyme inhibitory activities than the entire honeys, regardless the monofloral honey type. In conclusion, the studied Euphorbia honeys may have a great potential as antioxidant, anti-inflammatory and anti-tyrosinase sources for pharmaceutical and cosmetic applications.