Percorrer por autor "Valente, Luisa M. P."
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- Circular animal protein hydrolysates: a comparative approach of functional propertiesPublication . Monteiro, Marta; Rodrigues-dos-Santos, Luciano; Filipa-Silva, Andreia; Marques, Diana A.; Pintado, Manuela; Almeida, André; Valente, Luisa M. P.The growing demand for nutraceuticals has driven interest in upcycling low-value proteins from processed animal by-products and insect larvae into functional protein hydrolysates. This study evaluated five such hydrolysates in comparison to a high-value commercial reference (CPSP90), assessing the proximate composition, amino acid profile, molecular weight distribution, antioxidant activity, and bacterial growth dynamics. Results revealed a wide variability in the composition and bioactivity, driven by the raw material and processing conditions. All hydrolysates displayed a medium to high crude protein content (55.1–89.5% DM), with SHARK being the most protein-rich. SHARK and SWINE hydrolysates were particularly rich in collagenic amino acids, while FISH and CPSP90 contained higher levels of essential amino acids. FISH and INSECT demonstrated the strongest antioxidant activity, with INSECT also showing the highest protein solubility. INSECT and SWINE further displayed mild, selective antibacterial effects, indicating a potential for disease mitigation. Conversely, SHARK and FISH supported opportunistic bacteria growth, suggesting a potential use as nitrogen sources in microbial media. These findings highlight the nutritional and functional versatility of animal-derived protein hydrolysates and support their integration into sustainable feed strategies within a circular bioeconomy.
- Dietary inclusion of blood hydrolysates affects muscle growth in European seabass (Dicentrarchus labrax)Publication . Velasco, Cristina; Resende, Daniela; Oliveira, Beatriz; Canada, Paula; Pereira, Miguel; Pereira, Carlos; Pintado, Manuela; Valente, Luisa M. P.Dietary supplementation with hydrolysates has been suggested to influence muscle protein synthesis and fish growth. This study assessed the impact of including 3% swine blood hydrolysates (BH) in a plant-based diet on muscle cellularity and the expression of molecular markers related to muscle fibre proliferation and hypertrophic growth of European seabass. Three BH fractions were obtained by two different processes, autohydrolysis (AH-H) and enzymatic hydrolysis followed by micro- (RMF-H) and nanofiltration (RNF-H). Each BH was added to a commercial-based diet, where 50% of fishmeal was replaced by vegetable proteins (negative control, NC). A fishmeal-based diet was used as positive control, PC. The diets were fed to juveniles (12 g) during 74 days. The RMF group showed down-regulation of myod1 and fgf4, essential to myoblast proliferation and differentiation, and upregulation of mafbx, responsible for protein breakdown, resulting in impairment of muscle hyperplasic growth and the lowest muscle fibres number. However, compensatory growth mechanisms were observed through capn1 downregulation and mymk upregulation, suggesting decreased muscle proteolysis and increased myoblast fusion. Despite this, the compensatory mechanisms were insufficient as RMF group had the worst growth. RNF group had a final weight similar to the NC, but downregulation of fgf4, fgf6 and capn1 may compromise growth potential at long term. The expression of these genes in the AH group was similar to that in the FM-based diet. Despite not having demonstrated growth promotion ability, BH affect muscle growth and cellularity factors, prompting further research on commercial-sized fish to reveal their impact on important commercial traits.
- Effect of autoclaving process and enzymatic hydrolysis of okara (byproduct from soy beverage) on growth of nile tilapia o. niloticusPublication . Voss, Glenise B.; Rema, Paulo; Pintado, M. Manuela E.; Valente, Luisa M. P.
- Effect of protein and lipid levels in diets for adult sea urchin Paracentrotus lividus (Lamarck, 1816)Publication . Baião, Luís F.; Rocha, Filipa; Costa, Mónica; Sá, Tiago; Oliveira, Ana; Maia, Margarida R.G.; Fonseca, Antonio J. M.; Pintado, Manuela; Valente, Luisa M. P.Paracentrotus lividus gonads are considered a prized seafood delicacy due to its organoleptic features. The increasing market demand for sea urchin depleted several wild stocks, thus aquaculture can play an important role in supplying high-quality animals. Nevertheless, the success of this activity largely depends on the development of nutritionally balanced diets capable of producing excellent gonads. In this study, four extruded diets formulated with low or high protein (30 and 50% dry matter (DM), LP and HP, respectively) and lipid (6 and 11% DM, LL and HL, respectively) levels were fed to wild-caught individuals (4.5 cm diameter) for 15 weeks. Twelve homogeneous groups of 15 individuals were randomly distributed by mesh cages (45 urchins/m(2)) within 250 L tanks in a recirculating aquaculture system (RAS) at 18 degrees C and a 12 L:12 D photoperiod regime. Sea urchins fed the LP/LL diet were compared to wild specimens with similar maturation stage. All experimental diets were well accepted by sea urchins and resulted in similar final body weight (42-43 g). No significant differences were observed in specific growth rate or protein efficiency ratio among diets. The HP diets led to a decrease of dry matter and energy intake resulting in the lowest feed conversion ratio (FCR). Weight gain, whole body composition and nutrient gain remained similar among dietary treatments. The gonad somatic index (GSI) varied between sex but was similar among dietary treatments (19-23%) and was higher than values observed in wild specimens (6-7%). Females had significantly higher total concentration of carotenoids than males, irrespectively of the dietary treatments. Dietary treatments and sex did not affect gonad texture (firmness and resilience) or colour parameters (brightness, redness, yellowness, chroma or hue angle), but affected gonad composition. Total carotenoid content in gonads was not affected by diets and resulted in lower values compared to wild specimens. These had higher levels of echinenone, beta-cryptoxantin and beta-carotene and showed higher redness and firmness values when compared to the LP/LL diet, irrespectively of the sex. Gonad lipid content and n-3 PUFA were higher in female than in male, whilst protein content showed an opposite trend, suggesting some sex related differences in the metabolic use of nutrients. This study clearly shows that it is possible to enhance sea urchin gonad yield in relation to wild animals in a RAS at 18 degrees C. All diets were effective in promoting gonad growth, but the diet with the lowest protein (30% DM) and lowest lipid (6% DM) level resulted in the highest gonad yield in both sexes.
- Enzymatic hydrolysis of soymilk byproduct (Okara) by proteases extracted from Cynara CardunculusPublication . Voss, Glenise B.; Coscueta, Ezequiel; Valente, Luisa M. P.; Pintado, Maria M.Soybeans are the main oilseed produced and consumed worldwide. Currently, Brazil, Argentina and China are the largest producers of soybeans. This oilseed has great commercial interest, especially, because of the oil extraction, soy proteins and soymilk. Soymilk is used as a base in a wide variety of products, including tofu, soy yogurt and cheese. This soybean product is achieved by aqueous extraction of whole soybeans. During this process, a by-product known as okara rich in fiber, protein and fat, is obtained (3,4 5). Okara is produced in high amounts, since for each 1 kg of processed soybeans about 1.1 kg of okara is produced (1). The okara by-product has a high nutritive value, as previously mentioned. However, during soymilk manufacturing, this by-product is submitted to a severe heat treatment, which causes a large protein denaturation and the resulting okara protein isolate has poor solubility, which restricts its direct use in food. Studies reported that protein can be produced from the okara and that the protein isolates are characterized as having good amino acid profile and showing good digestibility (2). Beyond other functional properties emulsification, foaming and binding properties were comparable to those of commercial soy isolate. Therefore, the main objective of this work was to study the enzymatic hydrolysis of two okara substrates (dry okara, previously autoclaved (OA) and not autoclaved (ONA)), achieved by an enzymatic aqueous extract of Cynara cardunculus. The okara used in this study was provided by a local soybean producer in Portugal (NUTRE). After collection the okara samples were divided in two batches and one was submitted to heat treatment (1 atm, 121 ° C for 20 minutes) and the other was not heat treated. Finally, both were dried at 65 °C until constant weight and then milled with a 1 mm mesh. Two hydrolysis factors (reaction time and ratio of enzyme/substrate, E/S) were selected. The following parameters were analyzed: degree of hydrolysis (DH), antioxidant activity (ABTS) and the profile of hydrolysis (RH) determined by FPLC (fast protein liquid chromatography gel filtration). The hydrolysis was performed using commercial crude extract of Cynara cardunculus at 55 ° C and pH 5.2 for 2.5 to 5 h. No significant differences on the DH were observed between OA and ONA or between hydrolysis factors tested using the method of o-phthaldialdehyde (OPA). However, chromatographic analysis by FPLC showed strong protein hydrolysis after 2.5 h with formation of peptides fractions, with no significant difference between OA and ONA, but showing increasing concentration according increasing E/S rations. The antioxidant activity results showed a higher antioxidant potential for OA than for ONA and directly proportional to the time of hydrolysis, which proves that previous protein denaturation may promote the release of more antioxidant peptides. Therefore, it can be concluded that the hydrolysis of okara protein with C. cardunculus generated peptide extracts with relevant antioxidant activity, which is affected by the denaturation state of the proteins.
- Inclusion of blood hydrolysates in European seabass (D. labrax) diets: impact on nutrient retention and fish resistance to T. maritimum infectionPublication . Resende, Daniela; Costas, Benjamin; Sá, Tiago; Golfetto, Umberto; Machado, Marina; Pereira, Miguel; Pereira, Carlos; Marques, Bianca; Pereira, Ricardo; Pintado, Manuela; Valente, Luisa M. P.Bioactive peptides are small amino acid chains with interesting properties (beyond their nutritional value), including antioxidant, mineral-binding, immunomodulatory or antimicrobial activities [1]. In this study, we hypothesised that including blood hydrolysates (BH) in aquafeeds could promote fish robustness, increase the economic value of animal blood and minimize waste, contributing to a circular economy. Additionally, BH with antimicrobial properties may address the T. maritimum infections that occur in aquaculture farms, with high impact on fish health, well-being and aquaculture production. Three fractions of swine BH obtained by autohydrolysis (AH) or enzymatically were selected. AH was oven dried. The BH obtained enzymatically were further submitted to a micro- (MF) and nanofiltration (NF) and freeze-dried. Dried hydrolysates were then included in five isolipidic and isoproteic diets for European seabass: a fishmeal (FM) based diet (positive control, PC), a commercial-based diet where 50% of FM was replaced by vegetable proteins (negative control, NC) and three diets where 3% of each BH was added to the NC. Diets were assigned to triplicate groups of 71 juveniles (initial weight 12.3±1.4 g), fed three times daily until apparent satiation in a recirculating saltwater system. Growth, nutrient utilisation and whole-body composition were evaluated after 12 weeks. At the end of the trial, ten fish per tank were infected with Tenacibaculum maritimum (3.5×105 cfu/L), in a two-hour water bath, and mortality was assessed for 8 days. Fish fed PC had the highest final weight, followed by NC and NF. The NC had a significantly higher weight than the MF and AH groups. Specific growth rate (SGR) and feed conversion ratio (FCR) of fish fed NF showed no significant differences from those fed PC and NC. Fish fed AH also displayed similar SGR to those fed NF and NC, but differed significantly from the MF. Despite no significant differences among treatments regarding final body composition, lipid and energy retention and gain were lowest in fish fed MF, which also had the lowest condition factor. Protein retention was unaffected by dietary treatments. Regarding the infectious challenge, NF had the lowest mortality rate that differed significantly from the NC and MF groups. Mortality for fish fed AH and PC did not differ from NF. MF showed the highest mortality. Overall, results indicate that dietary supplementation with NF clearly improves the resistance of European seabass to T. maritimum without affecting growth rate and can hence become a valuable ingredient for this species.
- Inclusion of pineapple by-products as natural antioxidant sources in diets for European sea bass (Dicentrarchus labrax)Publication . Pereira, Ricardo; Basto, Ana; Pintado, Manuela; Valente, Luisa M. P.; Velasco, CristinaThis study investigates the effects of pineapple by-products on feed preservation during storage at two different temperatures (25 °C and 4 °C) and on European sea bass (Dicentrarchus labrax) stress resistance. Four isoproteic, isolipidic, and isoenergetic diets were manufactured: CTRL—negative control, commercial diet without added antioxidants; VITE—positive control, CTRL diet with 100 mg kg−1 of vitamin E; and P2 and S2—VITE diet with 2% pineapple peel or stem flour, respectively. The fish (13.5 ± 0.8 g) were split into four replicate groups per diet and fed ad libitum for 12 weeks, after which they were subjected to a stress challenge of air exposure (1 min) followed by confinement (5 min, 100 kg m−3). Despite storage time lowering the antioxidant properties of all diets, P2 and S2 showed increased antioxidant capacity (DPPH•, ABTS•+, and ORAC) before and after storage. The diets were well accepted by the fish, and the VITE-fed fish showed significantly lower lipid peroxidation values in the liver and muscle compared to all remaining diets. However, pineapple by-product inclusion did not result in increased fish stress resistance. Further optimization is required for the successful use of pineapple by-products as natural antioxidants in aquafeeds.
- Incorporating sardine cooking water aromas into plant-based diets for european seabass: effects on appetite regulation, growth and sensory properties of fish fleshPublication . Resende, Daniela; Velasco, Cristina; Pereira, Maria J.; Sá, Tiago; Rocha, Célia; Cunha, Luís M.; Lima, Rui C.; Brazinha, Carla; Pintado, Manuela; Valente, Luisa M. P.Sardine cooking wastewaters are by-products of the canning industry with great potential for valorisation. We have hypothesized that they can be a source of aromas to enhance appetite when added to plant-based diets. The poor palatability of such diets often described in carnivorous species poses a recurring problem in fish farming, with harsh consequences on fish growth performance and flesh quality. Aromas from sardine cooking wastewaters were collected without processing (CW-A), processed through vacuum distillation (VD-A), or processed through liquid/liquid extraction with soybean oil (LLE-A) into plant-based diets. Each aroma was added to a plant-protein based diet for European seabass, at a concentration of 2 μg of 1-penten-3-ol/g diet, resulting in 3 experimental diets (CW, VD and LLE). A non-supplemented diet was used as a control. Each diet was assigned to triplicate fish groups (initial weight 95.7 g), that were hand-fed twice daily until apparent satiation in a recirculating saltwater system at 21 °C. After 18 weeks, fish growth performance and nutrient utilisation were evaluated. The expression in the brain of neuropeptides involved in feed intake regulation was also analysed. Moreover, flesh colour and texture were assessed instrumentally and by sensory analysis using a consumer panel. Fish fed LLE displayed a significantly higher feed intake than those fed CW which was correlated with an increased neuropeptide Y expression in the hypothalamus. However, LLE slightly hindered lipid metabolism, leading to lower available glucose and resulting in statistically similar final weights among diets. Despite variations in fillet hardness, the sensory panel revealed similar overall liking across all treatments. The findings indicate that aromas from sardine cooking wastewaters can modulate feed intake, but further refinement in processing or incorporation levels is required to potentiate their efficacy.
- Locally-sourced animal protein hydrolysates in high-plant-protein diets can promote European seabass growth and nutrient utilization, reducing reliance on fishmealPublication . Rodrigues-dos-Santos, Luciano; Basto, Ana; Monteiro, Marta; António, Carla; Rodrigues, Ana M.; Sá, Tiago; Velasco, Cristina; Martins, Rui; Rosa, Ana; Pintado, Manuela; Almeida, André; Valente, Luisa M. P.Upcycling meat and fish by-products into bioactive protein hydrolysates promotes zero-waste practices within the circular bioeconomy and provides locally-sourced alternatives to replace fishmeal (FM) in aquafeeds. In this study, novel hydrolysates were developed from blue shark skin, fish by-products, and swine processed animal protein, aiming to reduce the high-quality FM inclusion in European seabass (Dicentrarchus labrax) diets. Four isoproteic (53%) and isolipidic (18%) plant-based diets were formulated: a control (CTRL) diet containing 12.5% FM was compared to three experimental diets, including 3% of each hydrolysate at the expense of FM-protein: SHARK, FISH, and SWINE. Seabass juveniles (13 g) stocked in 160 L tanks (3.9 kg/m3) were fed the diets in triplicate, three times daily until satiety, for 89 days. All diets were equally well accepted, promoting similar feed intake, daily growth index (1.6), and efficient feed conversion ratio (1.0–1.1). All fish at least quadrupled their initial size, but those fed the SWINE diet showed the highest body weight (55 g) and significantly higher condition factor (1.22), hepatosomatic index (HSI) (1.6), and viscerosomatic index (VSI) (8.4). Intestinal integrity remained similar across treatments, and apparent digestibility coefficients (ADCs) of protein and fat were above 96%. Iron (Fe) ADC was at least doubled with hydrolysates inclusion. Whole-body and muscle composition were similar across groups. However, the muscle metabolome of the SHARK-fed fish exhibited higher levels of glycolytic intermediates and lower levels of glucogenic amino acids (AAs) and fumarate, suggesting an increased catabolic activity. However, these changes were not reflected in fish growth performance or muscle flesh quality, which remained similar among treatments.
- A novel strategy to increase European seabass (D. labrax) resistance to tenacibaculosis: dietary supplementation with swine blood hydrolysatesPublication . Resende, Daniela; Costas, Benjamin; Sá, Tiago; Golfetto, Umberto; Machado, Marina; Pereira, Miguel; Pereira, Carlos; Marques, Bianca; Rocha, Cristina; Pintado, Manuela E.; Valente, Luisa M. P.