Browsing by Author "Oliveira, Catarina S. S."
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- In vivo study of the effect of sugarcane bagasse lignin supplementation on broiler chicken diet as a step to validate the established chicken gastrointestinal tract in vitro modelPublication . Carvalho, Nelson Mota de; Souza, Carla Giselly de; Costa, Célia Maria; Castro, Cláudia; Fangueiro, Joana F.; Horta, Bruno; Outor-Monteiro, Divanildo; Teixeira, José; Mourão, José Luís; Pinheiro, Victor; Amaro, Ana L.; Costa, Patrícia Santos; Oliveira, Catarina S. S.; Pintado, Manuela Estevez; Oliveira, Diana Luazi; Madureira, Ana RaquelSince the global restrictions on antibiotics in poultry systems, there has been a growing demand for natural and sustainable feed additives for disease prevention and poultry nutrition. This study evaluated the effects of incorporating sugarcane bagasse (SCB) lignin into broiler chicken diets. The performance of the chickens, including body weight, feed intake, and mortality, as well as intestinal histomorphometry, and cecum content pH, microbiota, and volatile fatty acids were assessed. In addition, we also aimed to validate an in vitro gastrointestinal tract (GIT) model developed by Carvalho et al. (2023). One hundred and eight 1-day-old Ross 308 chicks were randomly and equally divided into two groups. The first group was fed a basal diet (BD group), while the second group was fed a basal diet supplemented with 1% (w/w) SCB lignin (BD + SCB lignin group) for 36 days. The in vivo conditions of the chicken GIT were replicated in an in vitro model. In the in vivo study, SCB lignin increased cecum acetate and butyrate levels while reducing Bifidobacterium and Enterobacteriaceae, without affecting productivity (body weight, feed intake, and mortality). The in vitro assessment reflected microbiota trends observed in vivo, although without statistical significance. The divergence in organic acid production between the in vivo and in vitro conditions likely resulted from issues with inoculum preparation. This study demonstrates that SCB lignin incorporation positively influences cecal microbiota composition without impacting the animals’ productivity and physiology, suggesting its potential as a functional feed additive. For a more reliable in vitro model, adjustments in inoculum preparation are necessary.
- Polyhydroxyalkanoates from industrial cheese whey: production and characterization of polymers with differing hydroxyvalerate contentPublication . Carvalheira, Mónica; Hilliou, Loic; Oliveira, Catarina S. S.; Guarda, Eliana C.; Reis, Maria A. M.The composition of polyhydroxyalkanoate (PHA) monomers affects the properties and final applications of PHA polymers. This study focused on the feasibility of producing tailored PHA differing in hydroxyvalerate (HV) content, through manipulation of the acidogenic fermented stream composition, and on the characterization of PHA properties to determine the best composition for melt processing. Cheese whey was used as a feedstock, and changes in the organic loading rate during acidogenic fermentation led to the production of a fermented stream with an HV precursor content of 9–33 wt%. In the PHA production assays, a PHA content of 50 ± 11 wt%. (VSS basis) and yield of 0.76 ± 0.14 gCODPHA.gCODFP-1 were obtained. Fermented stream supplementation with HV precursors during the PHA accumulation assays indicated the feasibility of producing tailored PHA with differing HV content without a need for the selection of new cultures. The thermal properties of PHA were found to be controlled by the HV content, and PHA with approximately 30 wt% HV had the lowest melting temperature. These results demonstrated the robustness of the process at pilot scale, thus supporting full-scale applications in tailored PHA production.
- A simple ultraperformance liquid chromatography mass spectrometry method for the determination of cortisol level in sea bass plasmaPublication . Oliveira, Carla M.; Campos, Inês; Vidigal, Susana S. M. P.; Pintado, Manuela E.; Oliveira, Catarina S. S.A simple, precise, and rapid ultra-performance liquid chromatography method for cortisol quantification in sea bass plasma, based on LC-ESI-UHR-QqTOF-MS, was optimised using tolperisone as internal standard. Sea bass plasma samples containing cortisol were spiked with tolperisone as internal standard and extracted with acetonitrile. Samples were vortexed and centrifuged at 15,000g for 10 min at 4 °C. The final extract, diluted in ammonium formate (1:1), was injected in the LC-ESI-UHR-QqTOF-MS system for analysis. Mass spectrometry acquisition parameters were set using positive ionisation mode over a m/z range from 150 to 2200. Cortisol and tolperisone were detected and quantified at m/z 363.21 and 246.18, respectively, in an Auto MS (MS/MS) mode. The detection and quantification limits of cortisol in sea bass plasma were 0.01 and 0.02 μg/mL, respectively. The mean extraction recovery of cortisol was of 99.1 ± 4.0 %. The within- and between-day precision presents a relative standard deviation (RSD) below 2.9 % and 5.3, respectively. Furthermore, the effect of four different diets (fish feed 1–4) in the basal and stress-induced plasma cortisol levels of sea bass was also assessed.
- Valorization of spent sugarcane fermentation broth as a source of phenolic compoundsPublication . Oliveira, Carla Maria; Horta, Bruno; Leal, Tânia; Pintado, Manuela; Oliveira, Catarina S. S.A methodology based on a solid phase extraction (SPE) was optimized for the recovery of phenolic compounds from the spent fermentation broth generated from Biofene® (trans-β-farnesene) production. For this purpose, two resins (XAD-2 and HP-20) and three desorption solutions (water, 50/50 ethanol/water, and ethanol) were tested. The most efficient resin revealed to be the HP-20, using ethanol as desorption solution, reaching an overall total phenolic compound recovery of ca. 80% when 6 BV (bed volume) of both feed and ethanol were applied. The optimization of the resin’s process cycle pointed to 15 BV feed to be treated per cycle and using the same volume of ethanol in the desorption step, with no need for an extra resin regeneration step, stably yielding 48% total phenolic compound recovery from the spent broth for at least 4 cycles, translating into 60 BV of feed being treated per BV of resin, and with the resin being still perfectly active. The extract was characterized using LC−ESI−UHR−QqTOF−MS, and a total of 82 and 15 compounds were identified, in negative and positive ionization modes, respectively. Organic acids were the main class of compounds identified in the phenolic-rich extract, followed by phenolic compounds, saccharides, peptides or amino acids and vitamins. Additionally, the extract revealed a significant antioxidant capacity (914.1 ± 51.6 and 2764.5 ± 142.8 µmol Trolox equivalents/g-dw, respectively, with ABTS and ORAC methodologies), which might be interesting for a wide variety of applications.
- Valorization of sugarcane by-products through synthesis of biogenic amorphous silica microspheres for sustainable cosmeticsPublication . Costa, Joana R.; Capeto, Ana Paula; Pereira, Carla F.; Pedrosa, Sílvia S.; Mota, Inês F.; Burgal, João da Silva; Pintado, Ana I.; Pintado, Manuela E.; Oliveira, Catarina S. S.; Costa, Patrícia; Madureira, Ana RaquelAshes from sugarcane by-product incineration were used to synthesize silica powders through alkaline hot extraction, followed by ethanol/acid precipitation or the sol–gel method. Both production methods allowed amorphous spherical silica microparticles with sizes ranging from 1–15 μm and 97% purity to be obtained. Water absorption ranged from 135–155 mL/100 g and 150–250 mL/100 g for precipitated silica and silica gel, respectively, while oil absorption ranged from 305 to 390 and from 250 to 350 mL/100 g. The precipitation with ethanol allowed the recovery of 178 g silica/kg ash, with a lab process cost of EUR 28.95/kg, while the sol-gel process showed a yield of 198 g silica/kg ash with a cost of EUR 10.89/kg. The experimental data suggest that ash from sugarcane by-products is a promising source to be converted into a competitive value-added product, minimizing the environmental impact of disposal problems.