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- The biotechnological and seafood potential of Stichopus regalisPublication . Santos, Rita; Dias, Simaura; Pinteus, Susete; Silva, Joana; Alves, Celso; Tecelão, Carla; Pombo, Ana; Pedrosa, RuiSea cucumbers are highly used not only for the production of the bêche-de-mer, but also recent studies have been showing the high potential of these marine invertebrates on the pharmaceutical industry, as they are rich in bioactive compounds with important functions. Stichopus regalis extracts (1 mg∙mL−1) were used in antioxidant, antimicrobial and antitumor assays. The lipid profile was also evaluated. No significant antioxidant activity was detected in both methanolic and dichloromethane extracts. The methanolic fraction showed the highest antimicrobial potential against Candida albicans with an IC50 of 475.4 μg∙mL−1. In the antitumor assays, the dichloromethane fraction showed a high potential for both cell lines, as revealed by the MTT method. The total fat content was 3.63% ± 0.11% and the fatty acid profile revealed the highest amount in C16:0 (9.43% ± 0.77%), C18:0 (12.43% ± 0.83%), C18:1 ω7 (5.63% ± 0.33%), EPA (12.49% ± 0.15%), DHA (7.35% ± 0.02%), ARA (19.29% ± 0.14%) and a ω3/ω6 ratio of 1.078. These findings led us to suggest the potential use of S. regalis as a new source of bioactive compounds with pharmacological potential and its nutritional benefits for human health.
- Effect of three diets on the growth and fatty acid profile of the common ragworm Hediste diversicolor (O.F. Müller, 1776)Publication . Santos, António; Granada, Luana; Baptista, Teresa; Anjos, Catarina; Simões, Tiago; Tecelão, Carla; Fidalgo e Costa, Pedro; Costa, José Lino; Pombo, AnaThe polychaete Hediste diversicolor has a high physiological tolerance to extreme environmental factors, being easily farmed and reproduced in different types of conditions. Both in the field and under laboratory conditions, this worm can feed on different types of food. In order to highlight the potential of H. diversicolor for aquaculture, specific growth rate (SGR), daily growth rate (DGR), survival rate and fatty acid profile of juvenile worms, fed with three different diets, were assessed. The experiments were conducted using juvenile polychaete from a controlled reproduction with wild adults. H. diversicolor individuals were fed with two commercial diets, seabream dry feed (Aquagold) and semi-wet pellets for reared sole (Moist Sole), and with a non-processed diet consisting on mackerel's fillets (Trachurus trachurus). Juveniles fed with Aquagold had the highest final individual weight (0.89 ± 0.10 g). The SGR was higher in H. diversicolor fed with Aquagold and Moist Sole, (6.49 ± 0.30% d−1 and 6.54 ± 0.06% d−1 , respectively. The highest DGR was observed for juveniles fed with Aquagold (0.146 ± 0.02 g d−1 ). The survival rate of ragworms under different treatments ranged from 96 to 100%. Regarding the protein content, the Moist Sole diet provided the highest percentage of protein in the reared worms (8.87%). Results showed that the total fat content of the diets was reflected in the fat content of the reared worms. The Moist Sole diet treatment had the highest fat content (2.25%) and individuals fed with seabream dry feed showed similar results (2.18%), while the lowest percentage was observed for the mackerel diet (0.85%). According to the fatty acid profile, the major fatty acids found in the juveniles fed with the three different diets were palmitic (C 16:0), with a higher value in the individuals fed with mackerel's fillets. Oleic (C 18:1 n9), eicosapentaenoic (C 20:5 n3), docosahexaenoic (C 22:6 n3) and stearic (C 18:0) acids presented high values in H. diversicolor fed with all the experimental diets. Statement of Relevance: The common ragworm Hediste diversicolor is a potential high quality fatty acids source for reared fish and shrimp. Previous studies suggested that diet could be a relevant factor affecting the fatty acid composition of this polychaete (Luis and Passos, 1995). This study aimed to assess the effect of different diets on growth and survival of common ragworms juveniles (H. diversicolor), as well as the fatty acid profile and protein content in their tissues, aiming to find an appropriate diet to be used in commercial aquaculture.
- High dietary protein, n − 3/n − 6 ratio and β-carotene enhances Paracentrotus lividus (Lamarck, 1816) larval developmentPublication . Gomes, Ana S.; Lourenço, Sílvia; Santos, Pedro M.; Neves, Marta; Adão, Pedro; Tecelão, Carla; Pombo, AnaThe nutritional characteristics of microalgae affect the growth, survival and fatty acid composition of sea urchin larvae. This study aimed to evaluate the influence of nutritive characteristics of single microalgal diets in Paracentrotus lividus (Lamarck, 1816) larval development, growth, and condition. Larvae of P. lividus were fed with three monospecific microalgal diets, Rhodomonas sp. (Rho), Dunaliella tertiolecta (Duna) and the diatom Chaetoceros calcitrans (Chae), and their development and growth were analysed until competence. Additionally, the fatty acid (FA) profile of larvae was analysed at competence and compared with the FA profile of the correspondent diet. The three groups of larvae attained competence simultaneously with differences in growth performance. The larvae fed with Chae attained the largest stomach and the shortest post-oral arm. The larvae were able to accumulate long-chain polyunsaturated fatty acids (PUFA), such as docosahexaenoic (DHA, C22:6n − 3), eicosapentaenoic (EPA, C20:5n − 3) and arachidonic (ARA, C20:4n − 6) acids, either by assimilation and retention of dietary FA or by the synthesis from α-linolenic acid (ALA, C18:3n − 3) and linoleic acid (LA, C18:2n − 6). Furthermore, the low DHA/EPA ratio and high EPA/ARA and n − 3/n − 6 ratios of Rho and Chae and the high levels of the β-carotene present in Chae improved larval growth and development. In conclusion, the results indicated that of the three microalgal diets tested, C. calcitrans provided important nutritional characteristics, especially in terms of FA composition and carotenoids, improving P. lividus larval growth and condition.
- Enhancing oxidative stability of sunflower oil by supplementation with prickled broom (Pterospartum tridentatum) ethanolic extractPublication . Neves, Marta; Miranda, Andreia; Lemos, Marco F.L.; Silva, Susana; Tecelão, CarlaThis study aimed to evaluate the effect of ethanolic extract of Pterospartum tridentatum flowers in the stability of sunflower oil. The extract was characterized regarding to its antioxidant activity by the 2,2,1-diphenyl-1-picrylhydrazyl (DPPH) scavenging method (EC50 = 76.3 ± 2.6 μg/mL) and total phenolic content (200 ± 8 mg GAE/g). Extracts were added at 500 mg/L (E1) and 1,000 mg/L (E2), and after 30 days of storage at room temperature, E2 oil showed improved quality parameters,with a reduction of 22.4%,17.2%,and 45.6% in the values of acidity,peroxide,and p-anisidine, respectively.The extract also increased oil stability at 180 °C.After 27 hr, the acidity (0.216 ± 0.016 mg KOH/g) and the total oxidation value (TOTOX) (69.30 ± 0.26) values of E2 oil were significantly lower than the control. These results showed that P. tridentatum effectively improved the shelf-life and thermal stability of sunflower oil,being a promising source of antioxidants for edible oils processing.
- Bioactivity screening of Aurantiochytrium sp. for antioxidant activitiesPublication . Pinheiro, Joaquina; Garcia, Adriana; Paulo, Maria; Coutinho, Joana; Baptista, Teresa M.; Bernardino, Susana M.; Tecelão, Carla; Gil, Maria M.; Lemos, Marco F.L.Aurantiochytrium sp. is a heterotrophic microalgae that, in certain growth conditions, besides producing significant amounts of squalene, may potentially produce other bioactive compounds with high value and commercial interest such as docosahexaenoic acid (DHA), carotenoids, among others. Antioxidant compounds, naturally occurring in microalgae sources, have been identified as free radical or active oxygen scavengers, with beneficial effects on oxidation and oxidative damage inhibition in human body and foods. Several in vitro methodologies have been proposed to evaluate the antioxidant capacity, such as free radicals: 2,2-diphenyl-1-picrylhydrazyl (DPPH) and 2,2 -azino-bis (3-ethylbenzothiazoline-6-sulfonic acid) (ABTS+), and reactive species including hydrogen peroxide (H2O2), singlet oxygen (O2), and superoxide anion (O2-) (Balboa et al., 2013). The main objective of the present study was to evaluate the antioxidant activity of aqueous and ethanolic extracts of Aurantiochytrium sp., by means of different methodologies: reducing and scavenging activity by total phenolics content (TPC, Singleton & Rossi, 1965), DPPH (Custódio et al., 2012), and oxygen radical absorbance capacity (ORAC, Dávalos et al., 2004). The obtained results indicated that the microalgae Aurantiochytrium sp. is rich in antioxidant compounds, by reducing activity through total phenolics and DPPH, as well as scavenging activity by ORAC. Moreover, it is evident the higher selectivity of ethanol as solvent for the extraction of antioxidants compounds. The potential of this microalgae biomass as a good, natural and sustainable source for use as a functional food ingredient is evident, representing an opportunity with additional benefits due to the antioxidant role in diseases prevention and treatment.
- Enrichment of sunflower oil with ultrasound-assisted extracted bioactive compounds from Crithmum maritimum L.Publication . Sousa, Gabriela; Alves, Mariana I.; Neves, Marta; Tecelão, Carla; Ferreira-Dias, SuzanaCrithmum maritimum L., or sea fennel, is an edible halophyte plant, rich in phenolic compounds with antioxidant and antimicrobial activities, that naturally grows in Mediterranean coasts. This study aims to incorporate bioactive compounds extracted from lyophilized Crithmum maritimum to sunflower oil assisted by ultrasounds (UAE), to improve its biological value and oxidative stability. UAE conditions were optimized as a function of time (5–20 min) and lyophilized plant concentration (5–20% m/v). The experiments were dictated by a central composite rotatable matrix. Oxidation products were not influenced by UAE conditions. Acidity, chlorophyll, and carotenoid contents were affected by both factors, while total phenols, flavonoids, and antioxidant activity (FRAP method) only increased with plant concentration. Response surfaces were fitted to these experimental results. Flavonoids were highly related with oil antioxidant activity. No sensory defects were detected in supplemented oil (12.5% m/v plant/5 min UAE). The oxidative stability of this oil was evaluated at 60 °C/12 days. Chlorophylls, phenols, radical scavenging (DPPH), and antioxidant activities decreased over time but were always higher than the values in nonsupplemented oil (8.6 and 7‐fold with FRAP and DPPH, respectively). C. maritimum presented high amounts of bioactive compounds with antioxidant activity, adequate for sunflower oil supplementation by UAE.
- Somatic growth and gonadal development of Paracentrotus lividus (Lamarck, 1816) fed with diets of different ingredient sourcesPublication . Lourenço, Sílvia; Cunha, Beatriz; Raposo, Andreia; Neves, Marta; Santos, Pedro M.; Gomes, Ana S.; Tecelão, Carla; Ferreira, Susana M. F.; Baptista, Teresa; Gonçalves, Sílvia C.; Pombo, AnaSea urchins’ gonads are a delicacy highly appreciated worldwide. In Europe, Paracentrotus lividus is one of the most valuable edible sea urchin species and a desired target for aquaculture. One of the challenges of echinoculture is to increase the sea urchins’ growth rate during the on-growing phase and reducing the production cycle required to obtain sea urchins of commercial size (test diameter ≈ 50 mm). The present study aimed to evaluate the growth and gonad development of P. lividus urchins fed with three dry diets for 15 weeks. The diets were formulated with ingredients of three different sources: an algae-based, a fishmeal-based and a cereals-based diet. The somatic growth was assessed by biometric indicators like the linear and specific growth rates. The gonadal development was assessed by the gonadal somatic index (GSI), gametogenesis level, proximate composition and fatty acids profile. The results obtained showed high growth rates in all the three diets tested (0.44% per day). The sea urchins fed with the cereals diet presented the highest GSI (8.22%) with higher proportion of gonads in growing and premature stages. The proximate composition of the sea urchins’ gonads was significantly affected by diet and sea urchins’ sex, particularly the lipid content. Concomitantly, fatty acids (FA) profile of the gonads was influenced by both diet and sea urchins’ sex with saturated and polyunsaturated FA playing an important role in this differentiation.
- Enzymatic modification of grapeseed (Vitis vinifera L.) oil aiming to obtain dietary triacylglycerols in a batch reactorPublication . Bassan, Natalia; Rodrigues, Rafael Hatanaka; Monti, Rubens; Tecelão, Carla; Ferreira-Dias, Suzana; Paula, Ariela V.Structured lipids (SL) are chemically or enzymatically modified oils and fats with respect to their original fatty acid composition or position in acylglycerols. These compounds present improved functional or nutraceutical properties. The present work aimed at the enzymatic synthesis of SL, MLM-type dietary triacylglycerols, that is, those with medium chain fatty acids (M) at the sn-1 and sn-3 positions, and long chain fatty acids (L), in the internal position of the triacylglycerol. Grapeseed oil was selected based on its composition rich in unsaturated fatty acids, principally linoleic acid. This oil was submitted to batch acidolysis with medium chain fatty acids (caprylic or capric) in solvent-free media. Reactions were catalyzed by different immobilized commercial lipases, namely: Lipozyme TL IM® (Thermomyces lanuginosa lipase), Lipozyme RM IM® (Rhizomucor miehei lipase) and Novozym 435® (Candida antarctica lipase B). The incorporation degree (ID) ranged from 23.62 ± 1.34 to 34.53 ± 0.05 mol%, after 24 h reaction at 45 °C, using a molar ratio (MR) fatty acid:oil of 2:1. The best results were obtained using capric acid and Lipozyme RM IM® lipase (34.53 ± 0.05 mol%). In the experimental design, the influence of MR and temperature on ID were evaluated. ID increased with MR and T and was fitted to a saddle-like surface.
- Production of human milk fat substitutes by interesterification of tripalmitin with ethyl oleate catalyzed by candida parapsilosis lipase/acyltransferasePublication . Tecelão, Carla; Perrier, Véronique; Dubreucq, Eric; Ferreira-Dias, SuzanaIn human milk fat, the saturated fatty acids,namely palmitic acid, are located at the sn-2 position of triacylglycerols (TAG) while unsaturated fatty acids (e.g. oleic acid) are esterified at position sn-1,3. Thus, sn- 1,3-dioleoyl-2-palmitoylglycerol (OPO) is the target TAG to be used as human milk fat substitutes (HMFS) in infant formulas. In this study, the noncommercial recombinant lipase/acyltransferase from Candida parapsilosis (CpLIP2) was immobilized in Accurel MP1000, and used as a biocatalyst for the interesterification of tripalmitin with ethyl oleate in a solvent-free medium, to obtain structured lipids used as HMFS. Different molar ratios (MR) of ethyl oleate to tripalmitin (2:1–8:1) were used. After 4 h reaction at 60ºC, about 30 mol% of oleic acid incorporation was already observed for all tested MR. An apparent equilibrium was reached after 8–24 h, with 32–51 mol% final incorporation, increasing with the MR. The incorporation of oleic acid into TAG was compared with the maximum predicted values when a random or a sn-1,3-regioselective biocatalyst was used. The obtained values are consistent with the maximum incorporation expected for a sn-1,-3-regioselective enzyme. In fact, the amount of oleic acid at position sn-2 was approximately 15% for all the MR tested, which is explained by the acyl migration phenomenon. CpLIP2 exhibited higher activity than most commercial immobilized lipases (e.g. faster reaction in solvent-free media, low enzyme load, and low MR needed), and showed a recognized sn-1,3 regioselective behavior.
- Assessment of traditional mayonnaise enriched with Aurantiochytrium sp. extractPublication . Pinheiro, Joaquina; Garcia, Adriana; Paulo, Maria; Coutinho, Joana; Baptista, Teresa; Bernardino, Susana M.; Tecelão, Carla; Gil, Maria M.; Lemos, Marco F.Mayonnaise, a food product widely consumed since the 1900s, traditionally prepared from a mixture of oil, egg yolk and vinegar, has a reduced shelf-life primarily due to lipid oxidation (Kwon et al., 2015). The addition of synthetic antioxidants like BHT (butylated hydroxytoluene), BHA (butylated hydroxyl anisole), and EDTA (ethylenediaminetetraacetic acid) has been used to control this problem (Gray, 1978). However, these synthetic antioxidants showed several disadvantages such as the easily decomposition at higher temperatures, and an increased health risk for chronic consumers (Martinez-Tome et al., 2001). Natural antioxidants, derived from marine algae, show great potential for improving oxidative stability, extending the shelf-life of stored food products with additional health-promoting benefits (Hermund et al., 2015). Since 2004, the DHA-rich oil derived from the microalgae Aurantiochytrium sp. has been recognized as safe, available for food use and for dietary supplements. In general, Aurantiochytrium sp. became a popular source of protein-rich biomass and of valuable compounds like pigments, antioxidants and essential fatty acids. The potential of heterotrophic microalgae Aurantiochytrium sp. as a source of functional ingredient applied in mayonnaise product has not been evaluated yet. The aim of this study was to evaluate the quality of mayonnaise enriched with Aurantiochytrium extract by colour (L*, a*, b*, and ºh), texture (hardness, adhesiveness, resilience, cohesion, springiness, gumminess, and chewiness) and antioxidant capacity (DPPH and total phenolics content). The mayonnaise without extract was used as control sample. Colour results indicated that the luminosity of mayonnaise enriched with extract increased and the a* and b* colour parameters decreased, promoting a colour enhancement. Also, with the addition of Aurantiochytrium extract, a decrease in all texture attributes obtained by TPA profile test, with exception of cohesion and springiness, was observed. A correlation between antioxidant activity and total phenolics content was denoted, in all samples. The high antioxidant capacity can be related to high radical scavenging activity, high total phenolic content, and high carotenoid content of the extract. This study demonstrates that Aurantiochytrium sp extracts have the potential to be used as a nutraceutical/functional ingredient in mayonnaise, a product widely consumed by different age groups.
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