Browsing by Author "Valente, Luísa M. P."
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- Can sardine cooking wastewaters modulate European seabass feed intake?Publication . Resende, Daniela; Pereira, Maria J.; Sá, Tiago; Rocha, Célia; Cunha, Luís M.; Lima, Rui C.; Brazinha, Carla; Pintado, Manuela; Valente, Luísa M. P.; Velasco, CristinaThe goal of this work was to evaluate three extracts from sardine cooking waters, a by-product of the canning industry, as feed intake modulators, when included in highly vegetable diets, which often display low intake by carnivorous species. Sardine cooking waters, supplemented with acorn extract (Aroma 3) were processed, by vacuum condensation (Aroma 1) or liquid/liquid extraction with soybean oil (Aroma 2). Aromas were then included in a low-fishmeal diet (12.5%), achieving equal amounts of 1-penten-3-ol (2 μg/g). Diets were assigned to triplicate groups of 15 European seabasses (initial weight 95.7 ± 13.5 g) fed twice daily until apparent satiation in a recirculating saltwater system. Growth, nutrient utilization and wholebody composition were assessed after 18 weeks, along with both instrumental texture and color measurements and a sensory analysis of fillets. In parallel, a short-term trial was performed, in which fish fed the experimental diets were sampled 2 or 6 hours after the first feeding, for evaluation of neuropeptides involved in intake regulation. No significant differences among diets were found in fish final weight, specific growth rate, whole-body composition, and nutrient gain. Diet with Aroma 2 displayed a significantly higher voluntary feed intake than the Aroma 3, although both remained similar to the non-supplemented control. No differences on organoleptic properties were found by the panelists in the sensory analysis. No differences were found on neuropeptides expression 2h after feeding, but expression of orexigenic agrp2 was increased 6h post-feeding in all supplemented diets, in the telencephalon. Overall, results suggest that the aromas can modulate feed intake, but further optimization of incorporation levels should be performed as to see a clear effect on fish growth.
- Dietary inclusion of sardine cooking waters: impact on appetite regulation, growth and sensory properties of European seabassPublication . Resende, Daniela; Velasco, Cristina; Pereira, Maria J.; Sá, Tiago; Rocha, Célia; Cunha, Luís M.; Lima, Rui C.; Brazinha, Carla; Pintado, Manuela; Valente, Luísa M. P.Introduction Plant-based ingredients have been considered suitable options for replacing marinebased ones in aquafeeds (Naylor et al., 2021), but this may compromise diet palatability (Geurden et al., 2013), potentially affecting fish growth and flesh quality. To overcome this, feed attractants have been suggested. These compounds, like alcohols, aldehydes, and organic acids, were reported to stimulate intake in mammals (Chen et al., 2017; Takács et al., 2018). They can be obtained from agri-food by-products, within a circular economy framework. One example is the 9 m3 liquid waste generated by the canning industry per tonne of canned fish (Ferraro et al., 2013). The objective of this work was to extract aromas from the effluent waters of a canning industry and incorporate them in plant-based diets for European seabass. The aim was to evaluate their potential to modulate intake, growth and fillet organoleptic characteristics. Materials and methods Sardine cooking wastewaters were collected and either used directly (CW-A) or after processing by vacuum distillation (VD-A) or liquid/liquid extraction with soybean oil (LLE-A). Although the resulting extracts had different chemical profiles, the most abundant compound in all fractions was the 1-penten-3-ol. This was hence selected as marker and extracts containing 2 μg/g of this compound were incorporated in isolipidic and isoproteic diets (CW, VD and LLE) for European seabass. A non-supplemented diet was used as control (CTRL). Each diet was assigned to triplicate fish groups (initial weight 95.7 ± 13.5 g), hand-fed twice daily until apparent satiation in a recirculating saltwater system at 21 °C. After 18 weeks, growth performance and nutrient utilisation were evaluated. Flesh colour and texture were assessed instrumentally and by sensory analysis using a consumer panel. Moreover, the expression of neuropeptides involved in feed intake regulation (neuropeptide y – npy, agouti-related peptide – agrp2, cocaine and amphetamine-related transcript – carpt2 and pro-opiomelanocortin – pomca) in the brain was analysed. Metabolites in plasma and liver of fish were also quantified. Results and Conclusions Fish fed LLE displayed a significantly higher voluntary feed intake than those fed the CW diet, although neither differed from CTRL. LLE also resulted in increased feed conversion ratio. Final weight, whole-body composition, and nutrient gain were similar among diets. The expression of intake-regulating neuropeptides was not significantly affected by diets, but a slight upregulation of the orexigenic npy was observed for the LLE diet. In addition, fish fed this diet displayed the lowest plasmatic glucose and highest hepatic glucose and triglycerides values, although the remaining metabolites (lactate, non-esterified fatty acids, cholesterol and glycogen) were unaffected. Thus, the changes in feed intake are probably due to a combined effect of the homeostatic (nutrient-driven) and hedonic (pleasure-driven) regulation. No differences were found in skin or muscle colour among treatments. Despite a lower hardness in fillets of fish fed LLE when compared to those fed CTRL, no significant differences were perceived by the sensory panel; global liking of samples was similar among treatments, being all generally well accepted. Additionally, the samples’ taste and odour were characterized as “characteristic fish” and “soft” for all treatments. Overall, results suggest that aromas from sardine cooking wastewaters can modulate feed intake, but further optimization of either the processing and/or incorporation levels seems required to maximize their effectiveness as feed intake stimulants for application in aquafeeds.
- Effect of the dietary inclusion of blood hydrolysates on European seabass response to stressPublication . Resende, Daniela; Pereira, Ricardo; Velasco, Cristina; Domínguez, David; Pereira, Miguel; Pereira, Carlos; Marques, Bianca; Rocha, Cristina; Pintado, Manuela; Valente, Luísa M. P.
- European seabass response to air exposure: impact of dietary inclusion of bioactive blood hydrolysatesPublication . Resende, Daniela; Pereira, Ricardo; Velasco, Cristina; Domínguez, David; Pereira, Miguel; Pereira, Carlos; Marques, Bianca; Rocha, Cristina; Lima, Rui Costa; Pintado, Manuela; Valente, Luísa M. P.In aquaculture farms, fish are subjected to stress situations, which induce oxidative stress through an imbalance between the generation of reactive oxygen species (ROS) and the scavenging activity of antioxidants. Diet supplementation with functional ingredients to modulate oxidative stress after air exposure was investigated, using bioactive peptides from swine blood hydrolysates (BH), within a circular economy context. Three swine BH were obtained by autohydrolysis (AH) or enzymatically. The enzymatically produced BH were further submitted to a micro- (MF) or nanofiltration (NF). Five isolipidic and isoproteic diets for European seabass were developed: 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 European seabass juveniles (initial weight 12.3 ± 1.4 g), and fed to apparent satiation in a recirculating saltwater system. After 12 weeks, 9 fish per treatment were either immediately sampled or air-exposed for 1 minute and let to recover for 6 hours prior to sampling, in which plasma and liver were collected. Plasmatic cortisol and lactate were elevated for all diets after the air exposure, without differences among diets. Glucose levels were unaffected by diet or stress. Regarding liver oxidative stress markers, lipid peroxidation (LPO) tended to increase after air exposure. Considering the non-stressed fish, MF diet led to the lowest LPO, being significantly lower than the AH, and similar to the remaining diets. Protein oxidation decreased in stressed fish, but did not differ among diets. Liver catalase was significantly lower in NC, NF and AH groups compared to PC and increased after stress. Superoxide dismutase activity was lower for AH and PC diets than for the MF, and it was reduced in stressed fish. The stress response triggered by air exposure involved increased cortisol levels, followed by an increment in plasma lactate. However, none of the BH improved plasma stress response. The stress challenge increased liver LPO through ROS accumulation under oxidative stress. Carbonyls decreased post-stress, likely due to a feedback interaction with the LPO radicals, which reduced protein oxidation. The NF, composed of smaller peptides than the other BH, may modulate European seabass antioxidant defences by lowering catalase levels without increasing LPO, suggesting it could provide exogenous antioxidants to counteract ROS-induced oxidative stress.
- Exploring the influence of sardine cooking water extracts on the short-term regulation of feed intake in European seabassPublication . Resende, Daniela; Pereira, Maria J.; Sá, Tiago; Brazinha, Carla; Pintado, Manuela; Valente, Luísa M. P.; Velasco, CristinaIntroduction In fish, feed intake regulation is mediated by an interaction between homeostatic and hedonic signals (Soengas et al., 2018). The homeostatic control relates to biological needs regarding nutrients and energy (Soengas, 2021). On the other hand, the hedonic control is associated with reward-based routes, which are triggered by highly palatable food (Díaz-Rúa et al., 2022). Hedonic control may override homeostatic and maintain a drive to eat, due to the sensory pleasure felt by eating. Increasing the palatability of diets, such as those with high levels of plant-based ingredients, is therefore an important matter in aquaculture, as to achieve the best growth performance of fish. In addition, to evaluate the potential of a diet to affect the hedonic regulation of feed intake, long-term growth trials may be inadequate, since the need to maintain nutrient and energy homeostasis becomes more relevant over time. In parallel, the habituation effect to the diets occurs and masks the impact of diet palatability. Thus, studying feed intake stimulants, preferably obtained from by-products (considering a circular economy approach), on short-term trials may shed light on their impact on diet palatability and hedonic regulation of feed intake. In this work, we evaluated aromatic extracts from sardine cooking wastewaters as feed intake stimulants in plant-based diets for European seabass, focusing on the first feeding response towards the experimental diets. Materials and methods Sardine cooking wastewaters were collected and either tested directly (CW-A) or after vacuum distillation (VD-A) or after liquid/liquid extraction with soybean oil (LLE-A), resulting in distinct chemical profiles. The most abundant compound in the three extracts was 1-penten-3-ol, being thus chosen as marker and included at 2 μg/g in isolipidic and isoproteic diets (CW, VD, LLE). A practical plant-based diet (12.5% fishmeal and 4% fish oil) without any supplementation was used as control. Each diet was assigned to six homogeneous groups of European seabass juveniles (96 g). Fish were sampled 2 and 6 hours after a single first meal distributed to apparent satiation. Metabolites including glucose, lactate, cholesterol and non-esterified fatty acids were quantified in the plasma. Additionally, the mRNA abundance of neuropeptides involved in the regulation of feed intake, namely neuropeptide Y (npy), agouti-related peptide (agrp2), cocaine and amphetamine-related transcript (carpt2) and pro-opiomelanocortin (pomca) was quantified in the hypothalamus and telencephalon. Results and Conclusions Feed intake after the first meal was significantly higher for the control diet than for the supplemented diets. No significant differences on plasma metabolites were observed. Although the expression of neuropeptides involved in feed intake regulation was statistically similar among diets and sampling points, LLE and VD diets displayed the lowest expression of the agrp2 in the telencephalon, whilst LLE diet led to the highest expression of pomca, 2 hours after feeding. The similar profile of plasma metabolites among diets suggests that the regulation of feed intake in the tested fish was driven more by hedonic factors, such as reward or pleasure-driven, rather than homeostatic factors, such as nutrient-driven. The slightly lower expression of orexigenic (inducing feed intake) neuropeptide agrp2 in fish and higher expression of anorexigenic (supressing feed intake) neuropeptide pomca may be regulating factors associated with decreased feed intake observed in fish fed LLE and CW diets, but other factors might have also contributed to such results. Overall, the sardine cooking wastewaters extracts, in the tested concentration, had no positive effect on the short-term feed intake response of European seabass, which suggests that feed palatability was not enhanced. Further optimization of the extracts’ production process, and/or inclusion levels in diets should be considered in both short and long-term trials to improve effectiveness of the extracts as feed attractants.
- Growth and nutritional responses of bean and soybean genotypes to elevated CO2 in a controlled environmentPublication . Soares, José; Deuchande, Teresa; Valente, Luísa M. P.; Pintado, Manuela; Vasconcelos, Marta W.In the current situation of a constant increase in the atmospheric CO2 concentration, there is a potential risk of decreased nutritional value and food crop quality. Therefore, selecting strong-responsive varieties to elevated CO2 (eCO2) conditions in terms of yield and nutritional quality is an important decision for improving crop productivity under future CO2 conditions. Using bean and soybean varieties of contrasting responses to eCO2 and different origins, we assessed the effects of eCO2 (800 ppm) in a controlled environment on the yield performance and the concentration of protein, fat, and mineral elements in seeds. The range of seed yield responses to eCO2 was −11.0 to 32.7% (average change of 5%) in beans and −23.8 to 39.6% (average change of 7.1%) in soybeans. There was a significant correlation between seed yield enhancement and aboveground biomass, seed number, and pod number per plant. At maturity, eCO2 increased seed protein concentration in beans, while it did not affect soybean. Lipid concentration was not affected by eCO2 in either legume species. Compared with ambient CO2 (aCO2), the concentrations of manganese (Mn), iron (Fe), and potassium (K) decreased significantly, magnesium (Mg) increased, while zinc (Zn), phosphorus (P), and calcium (Ca) were not changed under eCO2 in bean seeds. However, in soybean, Mn and K concentrations decreased significantly, Ca increased, and Zn, Fe, P, and Mg concentrations were not significantly affected by eCO2 conditions. Our results suggest that intraspecific variation in seed yield improvement and reduced sensitivity to mineral losses might be suitable parameters for breeders to begin selecting lines that maximize yield and nutrition under eCO2.
- How to improve aquaculture sustainability?Publication . Resende, Daniela; Lima, Rui Costa; Pintado, Manuela; Cunha, Luís M.; Valente, Luísa M. P.
- Impact of fructose and fructooligosaccharides supplementation upon the fermentation of hydrolyzed okara and its impact upon bioactive componentsPublication . Voss, Glenise B.; Valente, Luísa M. P.; Pintado, Manuela E.Okara provide compounds of biological interest such as isoflavones and an increase of aglycone content can be obtained through fermentation with foodgrade bacteria. This study aimed to evaluate the effect of fructose and fructooligosaccharides (FOS) on the growth of probiotic bacteria in hydrolyzed (by Cynara cardunculus enzymes) okara beverage, as well as on the antioxidant activity, isoflavones and total phenolic content of fermented okara beverage. Okara beverages were fermented using Bifidobacterium animalis ssp. lactis Bb-12 and Lactobacillus rhamnosus R11 alone or as mixture of both, at 37 ºC, until it reached a pH value of 4.5. The growth of lactobacilli and bifidobacteria was evaluated throughout the fermentation, with increases of viable cells ranging from 1.5 to 3 log CFU/mL. Moreover, okara samples supplemented with a carbon source presented a higher growth rate than their non-supplemented counterpart, as expected. In addition, significant differences in aglycone content and antioxidant activity were observed for the okara samples fermented by different species, with the overall content of isoflavone aglycones increasing, the genistein presented the highest increase (ca. 16-fold) in the fermented okara by B. animalis ssp. lactis Bb-12. However, the antioxidant capacity was maintained in the okara without carbon source after fermentation by L. rhamnosus R11, while all fermented okara presented a decrease after fermentation process. Considering the hereby reported results, probiotic hydrolyzed fermented okara can be considered a good carrier for probiotic bacteria and a good source of aglycone isoflavones, combining all the other benefits resulting from probiotic metabolism and the hydrolyzed okara itself.
- Iodine enrichment of rainbow trout flesh by dietary supplementation with the red seaweed Gracilaria vermiculophyllaPublication . Valente, Luísa M. P.; Rema, Paulo; Ferraro, V.; Pintado, M.; Sousa-Pinto, Isabel; Cunha, Luís M.; Oliveira, M. B.; Araújo, MarianaThe effects of different dietary inclusion levels (0, 5 and 10%) of IMTA-cultivated Gracilaria vermiculophylla on rainbow trout growth performance and flesh quality traits were evaluated. Flesh chemical composition (moisture, protein, lipid, vitamin E and iodine contents), sensory attributes and instrumental color were determined after a feeding period of 91 days with the experimental diets. The antioxidant activity of muscle carotenoids and hydrolysates was also determined by the 2,2-azino-bis-3-ethylbenzothiazoline-6-sulfonic acid (ABTS) and 2,2-diphenyl-1-picrylhydrazyl (DPPH) methods. By the end of the experiment, fish fed CTRL or G5 diet reached similar body weight (215-220 g), but fish fed G10 weighed significantly less (167 g). Seaweed inclusion increased flesh moisture and decreased lipid content, with significant differences between the G5 and CTRL groups. Vitamin E content varied among treatments with CTRL fed fish presenting the highest levels of a-tocopherol. Iodine levels in the flesh increased with the seaweed inclusion, with fish fed G5 doubling its iodine content (214.5 mu g/kg) in relation to the CTRL (111.7 mu g/kg). Instrumental color showed that cooked fillets from fish fed seaweed-rich diets were more luminous (L*), less yellowish (b*) and more reddish (a*) than the CTRL. The sensory evaluation showed that fish fed with seaweed had juicier fillets than the CTRL with G5 presenting the most intense (pinkish) color. The instrumental differences are balanced in such away that the sensory panel perceived G5 as the sample with higher color intensity. Muscle carotenoid extracts presented no significant antioxidant activity through the ABTS and DPPH assays, whereas muscle hydrolysates showed similar antioxidant activity in all dietary treatments (ca. 33% through DPPH assay). The inclusion of Gracilaria sp. meal in diets for rainbow trout seems to be possible for up to 5%, as higher inclusion levels resulted in significantly smaller fish. The sensory panel perceived G5 as the sample with higher color intensity and juicier than the CTRL. Moreover, flesh iodine content doubled in fish fed G5, confirming seaweed as a natural and effective tool to increase the nutritional value of rainbow trout. Statement of relevance/impact of your paper to the general field of commercial aquaculture. This paper is relevant for the aquafeed industry and fish consumers. Fish meal has traditionally been the major dietary protein source for fish, but its reduction in aquafeeds is now a priority goal for the further expansion and sustainability of farmed fish production. Seaweeds may act as nutrient supply in fish, which in turn could ultimately function as vehicle of valuable compounds in human nutrition. This paper shows that 5% Gracilaria sp. meal can be a natural and effective tool to increase the nutritional value of rainbow trout flesh without impacting growth.
- Processed by‐products from soy beverage (Okara) as sustainable ingredients for nile tilapia (o. niloticus) juveniles: effects on nutrient utilization and muscle qualityPublication . Voss, Glenise B.; Sousa, Vera; Rema, Paulo; Pintado, Manuela E.; Valente, Luísa M. P.The apparent digestibility coefficients (ADCs) of differently processed okara meals were assessed in Nile tilapia diets: dried okara not autoclaved (FOK), dried okara autoclaved (AOK), okara hydrolyzed with Alcalase (ALOK) or Cynara cardunculus proteases (CYOK), and hydrolyzed okara fermented with lactic bacteria: Lactobacillus rhamnosus R11 (CYR11OK) or Bifidobacterium animalis ssp. lactis Bb12 (CYB12OK). Okara processing significantly affected nutrient digestibility: dry matter ADC was highest in CYR11OK (80%) and lowest in FOK (40%). The lowest protein digestibility was observed in CYR11OK (72%), and the highest in AOK (97%) and CYOK (91%), evidencing the effectiveness of the autoclave and the use of C. Cardunculus proteases to increase okara protein bioavailability. The inclusion of up to 20% of AOK or CYOK did not affect fish growth, nutrient utilization, or whole body composition of Nile tilapia. The flesh quality (color, pH, water activity, cohesiveness, elasticity and resilience) was not affected by the dietary incorporation of AOK or CYOK. Fish fed with AOK diets stand out for their high density of muscle fibers, particularly in AOK20, which can explain their high muscle firmness and may result in further hypertrophic growth. Altogether, results suggest that hydrolyzed or autoclaved okara are valuable ingredients for Nile tilapia diets.