Browsing by Author "Bronze, MR"
Now showing 1 - 2 of 2
Results Per Page
Sort Options
- Combined hydrothermal pre-treatment and enzymatic hydrolysis of corn fibre: production of ferulic acid extracts and assessment of their antioxidant and antiproliferative propertiesPublication . Valério, Rita; Serra, Ana Teresa; Baixinho, João; Cardeira, Martim; Fernández, Naiara; Bronze, MR; Duarte, Luís C.; Tavares, Maria L.; Crespo, João; Brazinha, CarlaABSTRACT: Ferulic acid may be used as a nutraceutical ingredient or as a substrate to produce bio-vanillin. There is an increasing market demand for ferulic acid obtained from natural sources such as low-cost agro-industrial by-products, due to its potential applications as nutraceutical ingredient and as a substrate to produce biovanillin. This work aims to study ferulic acid recovery from corn fibre (one of the most abundant natural sources of ferulic acid), involving an integrated process of hydrothermal pre-treatment followed by enzymatic hydrolysis. The objective is primarily to produce natural extracts with a maximum ferulic acid recovery yield, but it is also to assess their antioxidant and antiproliferative properties and their cytotoxicity. Different commercial enzyme preparations were tested for release of ferulic acid from corn fibre. The best results were obtained for Ultraflo (R) XL in a concentration of 2 % (W-enzyme preparation/W- dry corn fibre) at a pH of 5 and at 55 degrees C, presenting a recovery yield of esterified ferulic acid of 7.83 +/- 1.35 % (w(recovered ferulic acid)/w(total esterified ferulic acid)), which corresponds to 0.13 +/- 0.02 % (w(ferulic acid)/w (thy corn fibre)). When using a hydrothermal pretreatment at a temperature of 140 degrees C for 40 min, prior to the use of the same enzymatic hydrolysis procedure, the recovery yield of esterified ferulic acid increased to 28.94 +/- 2.40 % (W- recovered ferulic acid/ w(total esterified ferulic acid)), which corresponds to 4.9 +/- 0.3 % (w(ferulic acid)/w(dry corn fibre)). The use of this pre-treatment leads not only to the highest yield of ferulic acid, but also to the lowest concentration of furfural and hydroxymethylfurfural, without the formation of formic and levulinic acid (not detected). All pre-treatments tested led to an improved quality of the extract in terms of bioactivity.
- Sustainability assessment of collagen extraction from fish skins: A comparative life cycle assessment of conventional and NADES-enhanced processesPublication . Miguel P. Batista; Fernández, Naiara; Gaspar, Frédéric B.; Bronze, MR; Duarte, Ana Rita C.; Ortigueira, Joana; Lopes, TiagoABSTRACT: Collagen from blue shark skins offers a promising solution to utilize fishery by-products, reducing waste and improving resource efficiency. This study develops green chemistry-based extraction processes to minimize reliance on traditional chemical methods and lower environmental impacts, prioritizing sustainability and circularity. Two methods for collagen extraction are compared: a conventional alkaline-acid process and an innovative approach using natural deep eutectic solvents (NADES). Process simulations were conducted using SuperPro Designer software for the annual production of 500 kg of pure extracted collagen, followed by life cycle assessment (LCA) using SimaPro software and the Ecoinvent database, applying the Environmental Footprint (EF) method. For 1 kg of pure marine collagen from fish skin residues, defined as the Functional Unit, the conventional approach yielded a single-score impact of 48.1 mPt, while the NADES method achieved 41.5 mPt. Subsystem analysis reveals that, in the conventional method, the extraction and purification stages account for most of the environmental impact (43 % and 45 %, respectively). In contrast, the NADES method attributed 94 % of its total environmental impact to extraction stage, primarily due to NADES component production (citric acid, xylitol). Uncertainty analysis suggests that conclusions regarding impact reduction should be drawn with caution due to the environmental impact variability of considered inputs. Nevertheless, the mathematical model underscores the potential of the NADES method to reduce the environmental impact and promote more sustainable bioprocessing. This work offers valuable insights into the life cycle assessment of large-scale bioprocesses using green chemistry, providing a tool for optimization and environmental impact screening.