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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.
- Special issue CHEMPOR 2023 – 14th International Chemical and Biological Engineering ConferencePublication . Pinho, Simão; Barreiro, FilomenaThe 14th International Chemical and Biological Engineering Conference (CHEMPOR 2023), organized by Bragança Polytechnic University and the Portuguese Engineers Association, was held in Bragança, Portugal, on September 12–15, 2023. CHEMPOR 2023 focused on recent developments in various settings, including biorefinery, biotechnology, energy and environment, innovative materials, and the creation and design of novel reaction and separation processes, always foreseeing industrial applications for a sustainable future. The conference served as a melting pot to celebrate creativity, diversity, and friendship among participants, fostering the exchange of ideas and enabling fruitful interactions. It brought together professionals from the academic, industrial, scientific, and technological communities, uniting over 300 delegates from 12 countries. This collection of papers from CHEMPOR 2023 vividly illustrates how biological and chemical engineers are tackling the major societal challenges of our time. They highlight converging initiatives to promote sustainability through a circular economy where materials are valued and renewable. The papers present contemporary contributions in wastewater treatment, waste and biomass valorization, energy transition solutions, efforts to mitigate climate change, and bio-based approaches to produce, separate, and purify valuable compounds using ionic liquids or eutectic solvents. The selected works featured in this special issue represent an excellent reflection of the conference spirit. The attendees' dedication to seeking innovative solutions and producing high-quality scientific outputs also stood out. Finally, we want to express our profound appreciation to all the participants and our enormous gratitude to all our sponsors and associated scientific journals and publishers. In particular, we acknowledge the editorial team of Separation and Purification Technology, especially Bart Van der Bruggen and Raquel Aires-Barros, for their significant support and enthusiasm.
- 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.
- Special issue CHEMPOR 2023 – 14th International Chemical and Biological Engineering ConferencePublication . Pinho, Simão; Barreiro, FilomenaThe 14th International Chemical and Biological Engineering Conference (CHEMPOR 2023), organized by Bragança Polytechnic University and the Portuguese Engineers Association, was held in Bragança, Portugal, on September 12–15, 2023. CHEMPOR 2023 focused on recent developments in various settings, including biorefinery, biotechnology, energy and environment, innovative materials, and the creation and design of novel reaction and separation processes, always foreseeing industrial applications for a sustainable future. The conference served as a melting pot to celebrate creativity, diversity, and friendship among participants, fostering the exchange of ideas and enabling fruitful interactions. It brought together professionals from the academic, industrial, scientific, and technological communities, uniting over 300 delegates from 12 countries.
- Advancing Pickering emulsions with natural-based solid dispersion particles: Particle screening and design of pectin-based emulsionsPublication . Rezende, Stephany; Santamaria-Echart, Arantzazu; Ribeiro, Andreia; Dias, Madalena M.; Barreiro, FilomenaGiven the evolving trends in consumption, Pickering emulsions are emerging as a promising solution for functional and healthier foods, highlighting the need to diversify particle stabilisers. This study assessed the potential of curcumin-based solid dispersions (SDs) prepared with natural polymers (pectin, maltodextrin, Arabic gum, potato starch, and k-carrageenan) as Pickering stabilisers. Among these, pectin-curcumin SDs (contact angle = 48.0 ± 3.6◦) demonstrated effective emulsion stabilisation, as confirmed by confocal microscopy. The impact of oil volume fraction (φ = 0.20–0.70) and SD concentration (1.0–5.0 % wt.) on emulsion stability was evaluated. An intermediate φ (0.45) consistently minimised creaming index (CI = 0–16.67 %) and droplet size (D[4,3] =2.53–4.12 μm). Complete reduction of creaming (CI = 0 %) was achieved at high SD concentration with low φ or low SD concentration with high φ, leading to improved stability. The three produced optimised formulations exhibited distinct colour properties (L* = 64.06–72.00, a* = 11.09–12.50, b* = 55.10–60.70), with hues ranging from yellow to orange, highlighting their potential for natural colouring applications. Rheological behaviour varied from gel-like (G’ > G”) to viscoelastic (G’ = G”), broadening their potential in food formulations. Higher SD concentrations with lower/intermediate φ produced structured, gel-like emulsions suitable for sauces or spreads. In contrast, lower SD concentrations with higher φ yielded fluid emulsions for dressings or beverages. These findings highlight the feasibility of SD-based Pickering emulsions for designing stable (≥30 days), visually appealing, and texturally versatile food products.
- 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.