The European Union has established two designations, Protected Designation of Origin (PDO) and Pr... more The European Union has established two designations, Protected Designation of Origin (PDO) and Protected Geographical Indication (PGI), to guarantee the authenticity of products with valued specificities associated with the regions where they are produced. The valorization of these products, particularly fruits, not only preserves their natural origins but also promotes the cultivalion of specific regional fruit varieties. This contributes to the preservation of biodiversity and the development of innovative bio-based products in the regions of production. In recent years, substantial efforts have been made to characterize PDO and PGI fruits, particularly in relation to the presence of bioactive compounds with antioxidant and antimicrobial properties. Portugal, with its diverse range of climates and geographical characteristics, is home to numerous fruits with unique flavors, textures, and appearances, many of which are now recognized with PDO or PGI seals. This review compiles data...
The first ever nanofibers produced by the electrospinning of polyvinyl alcohol (PVA) and Spirulin... more The first ever nanofibers produced by the electrospinning of polyvinyl alcohol (PVA) and Spirulina platensis extracts are presented in this article. Spirulina platensis extracts were obtained by ultrasound-assisted extraction (UAE) using two different solvents: a glucose/glycerol-based natural deep eutectic solvent (NADES) and water. Through spectrophotometry analysis, it was possible to determine the pigment yield of the extractions for both extracts: phycocyanin = 3.79 ± 0.05 mg/g of dry biomass (DB); chlorophylls = 0.24 ± 0.05 mg/g DB; carotenoids = 0.13 ± 0.03 mg/g DB for the NADES/Spirulina extracts, and phycocyanin = 0.001 ± 0.0005 mg/g DB; chlorophylls = 0.10 ± 0.05 mg/g DB; carotenoids = 0.20 ± 0.05 mg/g DB for water/Spirulina extracts. Emulsions were formed by mixing the microalgae extracts in PVA (9%, w/v) at different concentrations: 5, 20, 40, and 50% (v/v). Electrospinning was carried out at the following conditions: 13 cm of distance to collector; 80 kV of applied volt...
Rita Pontes 1,2,3*, Aloia Romaní 2, Michele Michelin 2, Lucília Domingues 2, José Teixeira 2 and ... more Rita Pontes 1,2,3*, Aloia Romaní 2, Michele Michelin 2, Lucília Domingues 2, José Teixeira 2 and João Nunes 1 1 Association BLC3 Technology and Innovation Campus, 3405-155 Oliveira do Hospital, Portugal. 2 CEB Centre of Biological Engineering, University of Minho, Campus Gualtar, 4710-057 Braga, Portugal. 3 CNC Center for Neuroscience and Cell Biology, University of Coimbra, 3004-504 Coimbra. *corresponding author: rita.pontes@blc3.pt
The United Nations 2030 Agenda for Sustainable Development has created more pressure on countries... more The United Nations 2030 Agenda for Sustainable Development has created more pressure on countries and society at large for the development of alternative solutions for synthetic and fossil fuel derived products, thus mitigating climate change and environmental hazards. Food wastes and microalgae have been studied for decades as potential sources of several compounds that could be employed in various fields of application from pharmaceutical to textile and packaging. Although multiple research efforts have been put towards extracting rich compounds (i.e., phenolic compounds, tocopherols, and tocotrienols) from these sources, they still remain overlooked as two major sources of bioactive compounds and pigments, mainly due to inefficient extraction processes. Hence, there is a growing need for the development of optimized extraction methods while employing non-organic solvent options following the main principles of green chemistry. This review will focus on delivering a clear and deep...
The present paradigm of a new concept of biomass conversion system has been focused on the develo... more The present paradigm of a new concept of biomass conversion system has been focused on the development of a multi-supply biorefinery concept towards a circular and sustainable bioeconomy. This work was focused on evaluating a mixture of six lignocellulosic biomass types, from forest ecosystems and biological resources from marginal land, in order to produce lactic acid (L-LA) by Lactobacillus rhamnosus within a multi-supply biorefinery scheme. The mixture of lignocellulosic biomass was submitted to autohydrolysis pretreatment under non-isothermal regime at 226 °C (corresponding to a severity of 4.15) yielding a glucan recovery of 93 % in the solid phase. Two different strategies were assayed for L-LA production, namely separated hydrolysis and fermentation (SHF) and simultaneous saccharification and fermentation (SSF). The glucose to LA yield obtained for both assays was 1 g/g, although the volumetric productivity of SSF (2.5 g/Lh) was higher than SHF (0.8 g/Lh). Therefore, the SSF ...
This work was focused on evaluating two mixtures of lignocellulosic feedstock, forest and margina... more This work was focused on evaluating two mixtures of lignocellulosic feedstock, forest and marginal land resources, in order to co-produce solid biofuel, oligosaccharides, and glucose under a biorefinery concept. The selection of renewable bio-mixtures was based on different criteria, namely, territorial distribution, fire risk during summer months and total sugar content. The two mixtures were submitted to autohydrolysis pretreatment under non-isothermal conditions (in the range of 190 C-240 C corresponding to severity of 3.71e4.82). Both mixtures were compared in terms of fractionation (cellulose and lignin recoveries and hemicellulose solubilization), analyzed for thermal properties (high heating values) and for enzymatic susceptibility of cellulose. The highest xylan recoveries (62 and 69%), as xylose and xylooligosaccharides, were achieved for both mixtures in the liquid phase at 206 C. Autohydrolysis pretreatment increased the high heating values of the two mixtures presenting an alternative use of solid fraction as solid biofuel. Moreover, enzymatic susceptibility of these pretreated mixtures was also improved from 45 to 90% of glucose yield by increasing pretreatment severity. This comparative study of autohydrolysis showed a suitable process for the valorization of both mixtures within a biorefinery concept.
The European Union has established two designations, Protected Designation of Origin (PDO) and Pr... more The European Union has established two designations, Protected Designation of Origin (PDO) and Protected Geographical Indication (PGI), to guarantee the authenticity of products with valued specificities associated with the regions where they are produced. The valorization of these products, particularly fruits, not only preserves their natural origins but also promotes the cultivalion of specific regional fruit varieties. This contributes to the preservation of biodiversity and the development of innovative bio-based products in the regions of production. In recent years, substantial efforts have been made to characterize PDO and PGI fruits, particularly in relation to the presence of bioactive compounds with antioxidant and antimicrobial properties. Portugal, with its diverse range of climates and geographical characteristics, is home to numerous fruits with unique flavors, textures, and appearances, many of which are now recognized with PDO or PGI seals. This review compiles data...
The first ever nanofibers produced by the electrospinning of polyvinyl alcohol (PVA) and Spirulin... more The first ever nanofibers produced by the electrospinning of polyvinyl alcohol (PVA) and Spirulina platensis extracts are presented in this article. Spirulina platensis extracts were obtained by ultrasound-assisted extraction (UAE) using two different solvents: a glucose/glycerol-based natural deep eutectic solvent (NADES) and water. Through spectrophotometry analysis, it was possible to determine the pigment yield of the extractions for both extracts: phycocyanin = 3.79 ± 0.05 mg/g of dry biomass (DB); chlorophylls = 0.24 ± 0.05 mg/g DB; carotenoids = 0.13 ± 0.03 mg/g DB for the NADES/Spirulina extracts, and phycocyanin = 0.001 ± 0.0005 mg/g DB; chlorophylls = 0.10 ± 0.05 mg/g DB; carotenoids = 0.20 ± 0.05 mg/g DB for water/Spirulina extracts. Emulsions were formed by mixing the microalgae extracts in PVA (9%, w/v) at different concentrations: 5, 20, 40, and 50% (v/v). Electrospinning was carried out at the following conditions: 13 cm of distance to collector; 80 kV of applied volt...
Rita Pontes 1,2,3*, Aloia Romaní 2, Michele Michelin 2, Lucília Domingues 2, José Teixeira 2 and ... more Rita Pontes 1,2,3*, Aloia Romaní 2, Michele Michelin 2, Lucília Domingues 2, José Teixeira 2 and João Nunes 1 1 Association BLC3 Technology and Innovation Campus, 3405-155 Oliveira do Hospital, Portugal. 2 CEB Centre of Biological Engineering, University of Minho, Campus Gualtar, 4710-057 Braga, Portugal. 3 CNC Center for Neuroscience and Cell Biology, University of Coimbra, 3004-504 Coimbra. *corresponding author: rita.pontes@blc3.pt
The United Nations 2030 Agenda for Sustainable Development has created more pressure on countries... more The United Nations 2030 Agenda for Sustainable Development has created more pressure on countries and society at large for the development of alternative solutions for synthetic and fossil fuel derived products, thus mitigating climate change and environmental hazards. Food wastes and microalgae have been studied for decades as potential sources of several compounds that could be employed in various fields of application from pharmaceutical to textile and packaging. Although multiple research efforts have been put towards extracting rich compounds (i.e., phenolic compounds, tocopherols, and tocotrienols) from these sources, they still remain overlooked as two major sources of bioactive compounds and pigments, mainly due to inefficient extraction processes. Hence, there is a growing need for the development of optimized extraction methods while employing non-organic solvent options following the main principles of green chemistry. This review will focus on delivering a clear and deep...
The present paradigm of a new concept of biomass conversion system has been focused on the develo... more The present paradigm of a new concept of biomass conversion system has been focused on the development of a multi-supply biorefinery concept towards a circular and sustainable bioeconomy. This work was focused on evaluating a mixture of six lignocellulosic biomass types, from forest ecosystems and biological resources from marginal land, in order to produce lactic acid (L-LA) by Lactobacillus rhamnosus within a multi-supply biorefinery scheme. The mixture of lignocellulosic biomass was submitted to autohydrolysis pretreatment under non-isothermal regime at 226 °C (corresponding to a severity of 4.15) yielding a glucan recovery of 93 % in the solid phase. Two different strategies were assayed for L-LA production, namely separated hydrolysis and fermentation (SHF) and simultaneous saccharification and fermentation (SSF). The glucose to LA yield obtained for both assays was 1 g/g, although the volumetric productivity of SSF (2.5 g/Lh) was higher than SHF (0.8 g/Lh). Therefore, the SSF ...
This work was focused on evaluating two mixtures of lignocellulosic feedstock, forest and margina... more This work was focused on evaluating two mixtures of lignocellulosic feedstock, forest and marginal land resources, in order to co-produce solid biofuel, oligosaccharides, and glucose under a biorefinery concept. The selection of renewable bio-mixtures was based on different criteria, namely, territorial distribution, fire risk during summer months and total sugar content. The two mixtures were submitted to autohydrolysis pretreatment under non-isothermal conditions (in the range of 190 C-240 C corresponding to severity of 3.71e4.82). Both mixtures were compared in terms of fractionation (cellulose and lignin recoveries and hemicellulose solubilization), analyzed for thermal properties (high heating values) and for enzymatic susceptibility of cellulose. The highest xylan recoveries (62 and 69%), as xylose and xylooligosaccharides, were achieved for both mixtures in the liquid phase at 206 C. Autohydrolysis pretreatment increased the high heating values of the two mixtures presenting an alternative use of solid fraction as solid biofuel. Moreover, enzymatic susceptibility of these pretreated mixtures was also improved from 45 to 90% of glucose yield by increasing pretreatment severity. This comparative study of autohydrolysis showed a suitable process for the valorization of both mixtures within a biorefinery concept.
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