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- Biosynthesis of antioxidant xanthan gum by Xanthomonas campestris using substrates added with moist olive pomacePublication . Crugeira, Pedro Jorge Louro; Almeida, Heloísa H.S.; Marcet, Ismael; Rendueles, Manuel; Pires, Marcella Golini; Rafael, Helder Martins; Rodrigues, Ana Isabel G.; Santamaria-Echart, Arantzazu; Rafael, Helder; Barreiro, M.F.; Pires, Marcella GoliniMoist olive pomace (MOP) is a high moisture content by-product of the olive oil industry. Managing this recalcitrant residue (transport, storage, and drying) is a priority demanding investment in finding alternative valorisation routes. In this context, the biosynthesis of xanthan gum (XG) incorporating MOP in the substrate (0.0 %, 5.0 %, 10.0 %, 15.0 %, 20.0 %, 25.0 %, 30.0 % and 50.0 %) to induce bacterial stress was attempted. XG biosynthesis yield was quantified, and the product was characterised by structural analysis (FTIR), thermal behaviour (TG), rheology and antioxidant capacity. Relative to the control (sample with no added MOP), a significant increase in XG biosynthesis was found for concentrations up to 30.0 % MOP. In particular, for XG produced with 15 % MOP, a 50.91 % (p < 0.0001) increase was achieved, together with 395.78 % for viscosity. In general, XG produced with MOP presence showed antioxidant activity, a value-added property, especially for applications in the food, pharmaceutical and cosmetic areas. The results indicated that the stress imposed by the MOP induced a microbial response leading to XG production increase, structural and viscosity modifications, and antioxidant properties incorporation. Overall, this work points out a new MOP application contributing to the sustainability of the olive oil productive chain from a biobased circular economy perspective.
- Patente Nacional Nº 118006 - Método de produção de goma xantana com bagaço húmido da azeitona e aumento do biopolímero produzidoPublication . Crugeira, Pedro Jorge Louro; Barreiro, M.F.; Almeida, Heloísa Helena Scorsato de; Pires, Marcella Golini; Rafael, Helder Martins; Pires, Marcella GoliniO presente invento refere-se a um processo de produção de goma xantana, a partir da cepa de Xanthomonas campestris atcc 33913, com o uso do bagaço húmido da azeitona, proveniente da extração do azeite em sistema contínuo de duas fases. O método utiliza o bagaço húmido de azeitona pasteurizado até uma concentração de 45% suplementado com 2,0% de sacarose para meio de produção. Os polifenóis, poliálcoois e ácidos orgânicos existentes no resíduo induzem o estresse microbiano e consequente aumento da produção do exopolissacarídeo, como resposta à adaptabilidade celular e proteção às condições desfavoráveis. O dissacarídeo funciona como fonte de carbono, conseguindo-se uma relação aproximada de carbono/nitrogénio de 10:1, favorável a produção. A reutilização do bagaço húmido, resíduo recalcitrante, insere-se no processo sustentável e de inclusão no sistema de economia circular, reduzindo o custo do bioprocesso. O presente invento é aplicável, por exemplo, nas indústrias alimentares, farmacêuticas, agrícolas e petrolíferas.
- From berry plant cropping to a cosmetic formula: sustainable upcycling of active ingredientsPublication . Plasencia, Paula; Heleno, S.A.; Garcia, Pablo; Barreiro, Filomena; Barros, LillianDue to the interest in berry fruit's antioxidant properties, its worldwide production has been increasing in the past two decades, as has its waste. Bioresidues produced by the agri-food industry are increasingly intrinsic to the world’s economy, and researchers are looking for new ways to enhance their use. Innovations are being developed to transform these residues into high-value raw materials with industrial applications, promoting the circular economy concept. Bioactive extracts from blueberry and raspberry aerial parts using green methodologies were obtained for this work. Different extraction techniques were considered and different conditions were tested to achieve optimal extraction conditions.
- Chemical and bioactive characterization of blueberry bioresiduesPublication . Plasência, Paula; Heleno, S.A.; Garcia, Pablo; Barreiro, Filomena; Ferreira, Isabel C.F.R.; Barros, LillianBlueberry production has increased exponentially in recent decades due to its known high nutritional characteristics, and bioresidues originating from its culture have also increased. It is critical to limit its buildup. One strategy for directing these residues is to turn them into high-value products while investigating their potential bioactivity. The goal of this study was to produce bioactive extracts from blueberry aerial parts using environmentally friendly methods. Different extracts, such as infusion, maceration, and decoction, were considered, as well as emerging extraction technologies, such as ultrasound-assisted extraction, in which different conditions (potency, temperature, and solvent type) were tested to achieve optimal extraction conditions (high yields and purity). The obtained extracts were studied regarding their chemical profile through phenolic compound´s identification and quantification by HPLC-DAD-MS.
- Ethosomes: an approach for bioactive plant extract preservation envisaging cosmetic applicationsPublication . Plasencia, Paula; Santamaria-Echart, Arantzazu; Heleno, S.A.; Colucci, Giovana; Garcia, Pablo; Barros, Lillian; Barreiro, FilomenaThe present work is focused on upgrading the commercial potential of berry crop by-products by encapsulating them into liposomes to preserve their bioactivity. The extracts have been obtained with an ethanol-water mixture using ultrasound-assisted extraction, and the most promising ones were encapsulated in ethosome system. To achieve this goal, ethosomes were prepared using the cold method. Ethosomal suspensions were characterized concerning particle size distribution by laser dispersion, differential scanning calorimetry, infrared Fourier-transform spectroscopy, encapsulation efficiency, and morphological analysis using optical, scanning electron, and transmission electron microscopy. These results indicate that ethosomes are an appropriate method to encapsulate hydroethanolic bioactive plant bioresidue extracts and a good option to preserve them for further use in industrial applications, such as cosmetics. Future work will include optimizing the process and proof of concept by developing a cosmetic application.
- Spirulina (Arthrospira platensis) immobilization in calcium-alginate beads can provide a way to produce food-grade C-phycocyanin following a biorefinery perspectivePublication . Barreiro, Filomena; Silva-Pituco, Samara C.; Aquino, Leandro L.; Dias, Madalena M.C-phycocyanin (C-PC), a water-soluble blue pigment, is the primary phycobiliprotein in Spirulina. In this study, Spirulina was immobilized in calcium-alginate (SAC) beads as an innovative method to recover C-PC in the crosslinking bath while retaining the biomass within the beads. This approach simplifies the separation process and reduces costs. SAC beads were prepared via ionic gelation with alginate and CaCl2 at 2 % (PC2) and 4 % (PC4) concentrations. Different Spirulina to CaCl2 (S:CA) ratios (1:33, 1:42, 1:83, 1:125 w:v) were tested. PC4 extracts surpassed the food-grade purity threshold (≥ 0.7), achieving the highest purity of 0.83 at a 1:42 S:CA ratio. For PC2, the highest purity was 0.68, observed at a 1:83 S:CA ratio. Overall, this method effectively re- leases C-PC into the CaCl2 bath, attaining food-grade purity with significant extraction yields (> 50 mg/g biomass). Additionally, the SAC beads exhibited high protein levels (> 25 g/100 g d.w.) and can be further utilized within a biorefinery framework, either directly as a food supplement or for cascade extractions to recover the remaining lipid and protein fractions.
- E-Learning from nature: picking from nature the inspiration to teach and learn sciencePublication . Pereira, Ana I.; Ferreira, Olga; Barreiro, M.F.; Teixeira, Amílcar; Cortez, José Paulo; Aguiar, CarlosThis work aims to present the work done so far by he Polytechnic Institute of Bragança (IPB) within the projet E-learning form nature.
- Anti-inflammatory potential of mushroom extracts and isolated metabolitesPublication . Taofiq, Oludemi; Martins, Anabela; Barreiro, M.F.; Ferreira, Isabel C.F.R.Background: In the recent years natural resources are being in focus due to their great potential to be exploited in the discovery/development of novel bioactive compounds and, among them, mushrooms can be highlighted as alternative sources of anti-inflammatory agents. Scope and approach: The present review reports the anti-inflammatory activity of mushroom extracts and of their bioactive metabolites involved in this bioactive action. Additionally the most common assays used to evaluate mushrooms anti-inflammatory activity were also reviewed, including in vitro studies in cell lines, as well as in animal models in vivo. Key findings and conclusions: The anti-inflammatory compounds identified in mushrooms include polysaccharides, terpenes, phenolic acids, steroids, fatty acids and other metabolites. Among them, polysaccharides, terpenoids and phenolic compounds seem to be the most important contributors to the anti-inflammatory activity of mushrooms as demonstrated by numerous studies. However, clinical trials need to be conducted in order to confirm the effectiveness of some of these mushroom compounds namely, inhibitors of NF-κB pathway and of cyclooxygenase related with the expression of many inflammatory mediators.
- Valorization of lignin side-streams into polyols and rigid polyurethane foams—a contribution to the pulp and paper industry biorefineryPublication . Pinto, João A.; Fernandes, Isabel P.; Pinto, Virgínia; Gomes, Elson; Oliveira, Cátia F.; Pinto, Paula C.R.; Mesquita, L.M.R.; Piloto, P.A.G.; Rodrigues, Alírio; Barreiro, M.F.Valorization of industrial low-value side-streams are of great interest, contributing to boosts in the circular economy. In this context, lignin side-streams of the pulp and paper industry were oxypropylated to produce biobased polyols and tested in the synthesis of rigid polyurethane (RPU) foams. E. globulus lignins, namely a lignin isolated from an industrial Kraft black liquor and depolymerized lignins obtained as by-products of an oxidation process, were used. RPU foams, synthesized with 100% lignin-based polyols and using a 1.1 NCO/OH ratio, were characterized concerning apparent density, morphology, thermal conductivity, thermal stability, and heat release rate (HRR). Foams containing the lignin-based polyols presented densities varying from 44.7 to 112.2 kg/m3 and thermal conductivity in the range of 37.2–49.0 mW/mK. For the reference foam (sample produced with 100% wt. Daltofoam TP 32015 polyol), values of 70.9 kg/m3 and 41.1 mW/mK were obtained, respectively. The achieved results point out the viability of using the generated lignin-based polyols at 100% content in RPU foams, mainly when depolymerized lignins are used. Moreover, fire retardancy was favored when the lignin-based polyols were introduced. The proposed strategies can contribute to establishing the integrated pulp and paper biorefinery concept where material synthesis (polyols and RPU foams) can be combined with chemical production (vanillin and syringaldehyde).
- Extraction of Bioactive Compounds from Rubus Idaeus Bioresidues: A Full Screening on Phenolic Composition and Bioactive PotentialPublication . Plasencia, Paula; Finimundy, Tiane C.; Carocho, Márcio; Calhelha, Ricardo C.; Añibarro-Ortega, Mikel; Pires, Tânia C.S.P.; Barreiro, Filomena; Garcia, Pablo A.; Barros, Lillian; Heleno, Sandrina A.Purpose Rubus idaeus cultivation has boosted productivity due to its high nutritional value. In consequence, waste produc- tion increased. The discarded biomass, including leaves and aerial components, can be transformed into valuable functional ingredients for industrial applications, such as cosmetics. Studying their bioactivity potential is highly relevant. Methods According to the present idea, the research involved producing extracts from raspberry plant branches and leaves by employing four different techniques: aqueous decoction, aqueous infusion, hydroethanolic maceration, and ultrasound- assisted extraction (UAE). Subsequently, these compounds were screened for their bioactive potential, including antioxidant, antibacterial, anti-inflammatory, and cytotoxic properties. Results The ultrasound-assisted extraction produced extracts rich in phenolic compounds, whereas the infusion and macera- tion methods resulted in higher flavonol contents. Among the identified phenolic compounds, hydrolyzable tannins, particu- larly galloyl-bis-HHDP-glucose, were the most dominant ones. Regarding antioxidant potential, the decoction extract was the strongest, while the infusion showed the greatest potential for inhibiting lipid peroxidation. The UAE extract was found to be highly effective as an antibacterial agent. Both infusion and UAE extracts demonstrated the highest anti-inflammatory potential. Conclusion The combination of these results highlights the sample’s bioactive potential and the importance of exploiting bioresidues as unique, sustainable candidates for industrial applications.