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- Valorization of By-Products from Commercial Fish Species: Extraction and Chemical Properties of Skin GelatinsPublication . Sousa, Sérgio; Vázquez, José; Pérez-Martín, Ricardo; Carvalho, Ana; Gomes, AnaFish skins constitute an important fraction of the enormous amount of wastes produced by the fish processing industry, part of which may be valorized through the extraction of gelatins. This research exploited the extraction and characterization of gelatins from the skin of three seawater fish species, namely yellowfin tuna (Thunnus albacares), blue shark (Prionace glauca), and greenland halibut (Reinhardtius hippoglossoides). Characterization included chemical composition, rheology, structure, texture, and molecular weight, whereas extraction studies intended to reduce costly steps during extraction process (reagents concentration, water consumption, and time of processing), while maintaining extraction efficiency. Chemical and physical characterization of the obtained gelatins revealed that the species from which the gelatin was extracted, as well as the heat treatment used, were key parameters in order to obtain a final product with specific properties. Therefore, the extraction conditions selected during gelatin production will drive its utilization into markets with well-defined specifications, where the necessity of unique products is being claimed. Such achievements are of utmost importance to the food industry, by paving the way to the introduction in the market of gelatins with distinct rheological and textural properties, which enables them to enlarge their range of applications.
- Use of coffee by-products for the cultivation of Pleurotus citrinopileatus and Pleurotus salmoneo-stramineus and its impact on biological properties of extracts thereofPublication . Freitas, Ana C.; Antunes, Mariana B.; Rodrigues, Dina; Sousa, Sérgio; Amorim, Manuela; Barroso, Maria de Fátima; Carvalho, Ana; Ferrador, Sandra M.; Gomes, Ana M.Incorporating spent coffee grounds (SCGs), a by-product from coffee brewing, in growth substrate of ben-eficial edible mushrooms is an approach that has to be further studied due to its potential positive out-comes: environmental impact mitigation, production costs reduction and beneficial impact on consumerhealth. Hence, cultivation ofPleurotus citrinopileatusandPleurotus salmoneo-stramineuswas tested usingSCG which enabled maximum production yield ofP. citrinopileatuswhich was of 25.1% (w/w). Variableantidiabetic potential was observed between aqueous and enzymatic extracts (3.8%–29% inhibition)regardless species and substrates, whereas aqueous extract ofP. citrinopileatusgrown in substrate withoutSCG stood out presenting the highest antioxidant activity and inhibition activity of angiotensin I-convert-ing enzyme (IC50=123lgmL 1). Ethanolic and aqueous extracts of bothPleurotusspecies grown in thepresence or absence of SGC proved to be an interesting prebiotic source for growth ofBifidobacteriumanimalisBo in comparison with fructooligosaccharides (FOS)
- Bioactive Lipids of Seaweeds from the Portuguese North Coast: Health Benefits versus Potential ContaminationPublication . Soares, Cristina; Sousa, Sara; Machado, Susana; Vieira, Elsa; Carvalho, Ana P.; Ramalhosa, Maria João; Morais, Simone; Correia, Manuela; Oliva-Teles, MT; Domingues, Valentina; Delerue-Matos, CristinaThe total lipid content and lipidic profile of seaweeds harvested in the North Coast and purchased in Portugal were determined in this paper. The amount of total lipids in the different species of seaweeds varied between 0.7 ± 0.1% (Chondrus crispus) and 3.8 ± 0.6% (Ulva spp.). Regarding the fatty acid content, polyunsaturated fatty acids (PUFA) ranged between 0–35%, with Ulva spp. presenting the highest amount; monounsaturated fatty acids (MUFA) varied between 19 and 67%; and saturated fatty acids (SFA) were predominant in C. crispus (45–78%) and Gracilaria spp. (36–79%). Concerning the nutritional indices, the atherogenicity index (AI) was between 0.4–3.2, the thrombogenicity index (TI) ranged from 0.04 to 1.95, except for Gracilaria spp., which had a TI of 7.6, and the hypocholesterolemic/hypercholesterolemic ratio (HH) values ranged between 0.88–4.21, except for Gracilaria spp., which exhibited values between 0.22–9.26. The n6/n3 ratio was below 1 for most of the species evaluated, except for Ascophyllum nodosum, which presented a higher value, although below 2. Considering the PUFA/SFA ratio, seaweeds presented values between 0.11–1.02. The polycyclic aromatic hydrocarbons (PAHs) and aliphatic hydrocarbons (AHCs) contamination of seaweeds under study was also quantified, the values found being much lower than the maximum levels recommended for foodstuff.
- Development of New Canned Chub Mackerel Products Incorporating Edible Seaweeds—Influence on the Minerals and Trace Elements CompositionPublication . Vieira, Elsa F.; Soares, Cristina; Machado, Susana; Oliva-Teles, MT; Correia, Manuela; Ramalhosa, Maria João; Carvalho, A.; Domingues, Valentina; Antunes, Filipa; Morais, Simone; Delerue-Matos, CristinaThis study aimed to develop new canned chub mackerel products incorporating edible seaweeds (Ascophyllum nodosum, Fucus spiralis, Saccorhiza polyschides, Chondrus crispus, Porphyra sp. and Ulva sp.) harvested in the Portuguese North-Central coast, with simultaneous sensory improvement and minerals enrichment. Two processes were compared, namely the addition of seaweeds in i) the canning step and ii) in the brining step (as the replacement for salt). The concentrations of four macrominerals (Na, K, Ca and Mg), chloride, and twelve trace elements (Co, Cu, Fe, I, Li, Mn, Mo, Rb, Se, Sr, V and Zn) were determined by high-resolution continuum source flame atomic absorption spectrometry (HR-CS-FAAS) and inductively coupled plasma mass spectrometry (ICP-MS), respectively. Results showed that canned chub mackerel incorporating C. crispus and F. spiralis was found to be the preferred sensory option, also exhibiting contents enriched with Cl, Co, Cu, Fe, I, Li, Mg, Mn, Mo, Na, Rb, Se, and Sr. This effect was more pronounced when both seaweed species were added to replace the salt added in the brining step.
- Bioactive compounds of sweet and sour cherry stems obtained by subcritical water extractionPublication . Švarc-Gajić, Jaroslava; Cerdà, Víctor; Clavijo, Sabrina; Suárez, Ruth; Mašković, Pavle; Cvetanović, Aleksandra; Delerue-Matos, Cristina; Carvalho, Ana; Novakov, VesnaBACKGROUND Sweet cherries (Prunus avium L.) and sour cherries (Prunus cerasus L.) contain substantial amounts of anthocyanins and polyphenolics, and their stems have been used in traditional medicine for centuries. However, comparative data on the composition of sweet and sour cherry stems using the same analytical methodologies are limited. Moreover, there is no data in terms of biological activity of subcritical water extracts of cherry stems. RESULTS AND DISSCUSION Results obtained by using several assays that focused on different mechanisms showed that subcritical water extracts of sour and sweet cherry stems were powerful antiradicals and antioxidants. Anti‐proliferative properties measured by MTT (3‐[4,5‐ dimethylthiazol‐2‐yl]‐2,5 diphenyl tetrazolium bromide) test showed prominent cytotoxicity against different tumor cell lines. Inhibitory concentrations obtained were in the range 8.38–11.40 µg mL‐1. GC–MS (gas chromatography mass spectrometry) analysis showed the presence of alcohols, fatty acids, organic acids and other organic compounds. However, the chemical compositions of the two samples observed were similar, indicating similar chemical composition of sour and sweet cherry stems. CONCLUSION Subcritical water extracts of cherry stem demonstrated excellent biological activity and the potential to be used for pharmaceuticals or supplements due to confirmed high antioxidant, antiradical and antitumor activity.
- Sardine Canning Byproducts as Sources of Functional IngredientsPublication . Carvalho, Ana P.; Amorim, Manuela; Rodríguez-Alcalá, Luís; Fontecha, Javier; Castro, Paula M. L.; Pintado, Manuela E.Sardine by-products generated during canning process entail a potential opportunity to drive them into a chain of high added-value compounds, while simultaneously decreasing the environmental impact of their discharge. This paper describes and discusses the biochemical variation of solid and liquid by-products generated during the canning process of sardine along one complete year. Additionally, by-products were also evaluated in terms of their degradation along time, monitored through microbiological and chemical analysis. Finally, their valorisation was ascertained through the recovery of lipid fractions rich in ω3 polyunsaturated fatty acids (PUFA), as well as protein fractions with anti-hypertensive activity (ACE). The variability within biochemical composition of by-products along the year is significant, especially in terms of lipid content, and their degradation is strongly dependent on the conditions in which they were collected and stored. Both liquid and solid by-products present ω6/ω3 ratios between 0.05-0.18 and thrombogenic index between 0.27-0.57, whereas low-molecular-weight fractions of protein extracts (<3 kDa) exhibited the strongest ACE activity (IC50 = 51 µg/ml). The potential viability of using liquid by-products as sources of functional ingredients is an interesting alternative to the management of these effluents in fish canning industry.
- Liquid by-products from fish canning industry as sustainable sources of ω3 lipidsPublication . Monteiro, Ana; Paquincha, Diogo; Martins, Florinda; Queirós, Rui P.; Saraiva, Jorge A.; Švarc-Gajić, Jaroslava; Nastić, Nataša; Delerue-Matos, Cristina; Carvalho, Ana P.Fish canning industry generates large amounts of liquid wastes, which are discarded, after proper treatment to remove the organic load. However, alternative treatment processes may also be designed in order to target the recovery of valuable compounds; with this procedure, these wastewaters are converted into liquid by-products, becoming an additional source of revenue for the company. This study evaluated green and economically sustainable methodologies for the extraction of ω3 lipids from fish canning liquid by-products. Lipids were extracted by processes combining physical and chemical parameters (conventional and pressurized extraction processes), as well as chemical and biological parameters. Furthermore, LCA was applied to evaluate the environmental performance and costs indicators for each process. Results indicated that extraction with high hydrostatic pressure provides the highest amounts of ω3 polyunsaturated fatty acids (3331,5 mg L-1 effluent), apart from presenting the lowest environmental impact and costs. The studied procedures allow to obtain alternative, sustainable and traceable sources of ω3 lipids for further applications in food, pharmaceutical and cosmetic industries. Additionally, such approach contributes towards the organic depuration of canning liquid effluents, therefore reducing the overall waste treatment costs.
- Identification of Eschweilenol C in derivative of Terminalia fagifolia Mart. and green synthesis of bioactive and biocompatible silver nanoparticlesPublication . Araujo, Alyne Rodrigues de; Ramos-Jesus, Joilson; Oliveira, Taiane Maria de; Carvalho, Andressa Maria A. de; Nunes, Paulo Humberto M.; Daboit, Tatiane Caroline; Carvalho, Ana P.; Barroso, M. Fátima; Almeida, Miguel Peixoto de; Plácido, Alexandra; Rodrigues, Artur; Portugal, Camila C.; Socodato, Renato; Relvas, João B.; Delerue-Matos, Cristina; Silva, Durcilene Alves da; Eaton, Peter; Leite, José Roberto de Souza de A.A green synthetic route was developed to prepare silver nanoparticles (AgNPs) in aqueous solution for biological applications. Eschweilenol C, a compound derivative ellagic acid was identified as the main constituent of the aqueous fraction of the ethanolic extract of Terminalia fagifolia Mart. by NMR analysis. In the green synthesis, the ethanolic extract of T. fagifolia and its aqueous fraction were used to promote silver reduction and nanoparticle stabilization. The synthesized AgNPs presented a spherical or polygonal morphology shape by TEM analysis and AgNPs showed high levels of antioxidant and considerable antibacterial and antifungal activities. Synthesized nanoparticles presented significant antioxidant activity by sequestration of DPPH and ABTS radicals, in addition to iron reduction (FRAP assay) and measurement of antioxidant capacity in ORAC units, in addition, AgNP synthesized with the aqueous fraction also demonstrated antioxidant potential in microglial cells. Gram-positive and Gram-negative bacteria were susceptible to growth inhibition by the nanoparticles, among which the AgNPs formed by the ethanolic extract was the most effective. The data obtained by AFM images suggested that AgNPs could lead to the lysis of bacteria and subsequent death. The antifungal assays showed high efficiency against yeasts and dermatophytes. This work represents the first description of antifungal activity by AgNPs against Fonsecaea pedrosoi, the etiologic agent of chromoblastomycosis. In relation to biocompatibility, the AgNPs induced lower haemolysis than AgNO3.
- Seaweeds from the Portuguese coast as a source of proteinaceous material: Total and free amino acid composition profilePublication . Vieira, Elsa Ferreira; Soares, Cristina; Machado, Susana; Correia, Manuela; Ramalhosa, Maria João; Oliva-Teles, MT; Carvalho, Ana; Domingues, Valentina; Antunes, Filipa; Oliveira, Teresa Azevedo Cardoso; Morais, Simone; Delerue-Matos, CristinaThe total protein content and the (total and free) amino acid composition of nine edible species of red, brown and green seaweeds collected in the Portuguese North-Central coast were quantified to assess their potential contribution to the recommended dietary intake. Whenever possible, the protein and amino acid composition was compared with that of commercial European seaweeds. The protein content was the highest (P < 0.05) in red species (19.1-28.2 g/100 g dw), followed by the green seaweed Ulva spp. (20.5-23.3 g/100 g dw), with the lowest content found in brown seaweeds (6.90-19.5 g/100 g dw). Brown seaweeds presented the lowest mean contents of essential amino acids (EAAs) (41.0% protein) but significantly (P < 0.05) higher concentrations of non-essential amino acids (36.1% protein) and free amino acids (6.47-24.0% protein). Tryptophan, methionine and leucine were the limiting EAAs in all species. In contrast, lysine was found in high concentrations, especially in red (2.71-3.85% protein) and green (2.84-4.24% protein) seaweeds.