Browsing by Author "Monteiro, I."
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- Lipid composition and some bioactivities of 3 newly isolated microalgae (Tetraselmis sp. IMP3, Tetraselmis sp. CTP4, and Skeletonema sp.)Publication . Cardoso, Cátia; Pereira, H.; Franca, J.; Matos, J.; Monteiro, I.; Pousão-Ferreira, P.; Gomes, A.; Barreira, Luísa; Varela, Varela J.; Neng, N.; Nogueira, J. M.; Afonso, C.; Bandarra, N. M.Recently isolated microalgae Tetraselmis sp. IMP3, Tetraselmis sp. CTP4, and Skeletonema sp. were studied. The three novel strains contained relatively high levels of polyunsaturated fatty acids (PUFA) and n3 PUFA. However, highly unsaturated n3 FA contents were relatively low (5.7-13.0% of the total FA). In general, eicosapentaenoic acid (EPA, 20:5 n3) contents were low (< 6.4% of the total FA). However, in Skeletonema biomass, EPA levels were higher than 10% of the total FA. alpha-Linolenic acid (ALA, 18:3 n3) and 16:3 n4 were the main PUFA in Tetraselmis strains and Skeletonema, respectively. High contents of myristic (14:0) and palmitoleic (16:1 n7) acids were found in Skeletonema (exceeding 20% of the total FA in both cases), whereas the Tetraselmis strains were rich in palmitic (16:0), 15-27% of the total FA, and oleic (18:1 n9) acids, 12-19% of the total FA. Linoleic acid (18:2 n6) content was low in Skeletonema (< 1% of the total FA). This microalga had the highest total polyphenol content, reaching 300-400 mg/100 g dw. Gentisic acid was the main phenolic compound in the aqueous and ethanolic extracts of this microalga. The highest antioxidant activity was displayed by Skeletonema. The ferric ion reducing antioxidant power (FRAP) and 2,2 '-azino-bis(3-ethylbenzothiazoline-6-sulphonic acid) (ABTS) methods showed higher antioxidant power for Skeletonema sp. extracts, reaching an ABTS reduction of more than 80%. Concerning anti-inflammatory activity, ethanolic extracts of Skeletonema sp. exhibited the highest inhibitory capacity of cyclooxygenase-2 (COX-2), 82 +/- 2%, which compares to 36 +/- 9% in Tetraselmis sp. CTP4 and 45 +/- 5% in Tetraselmis sp. IMP3. Aqueous extracts had always a lower anti-inflammatory capacity, 6-30%. Therefore, these microalgae have potential for multiple applications, ranging from bioactive feedstocks to aquaculture and nutraceutical uses.
- Methodology for assessing the individual role of fish, oyster, phytoplankton and macroalgae in the ecology of integrated production in earthen pondsPublication . Cunha, M.E.; Quental-Ferreira, H.; Parejo, A.; Gamito, Sofia; Ribeiro, L.; Moreira, M.; Monteiro, I.; Soares, F.; Pousão-Ferreira, PedroProduction costs in extensive and semi-intensive fish culture in earthen ponds are often too high to offer sustainable economic activity due to the low productivity of these systems. The right combination of commercial finfish species with inorganic (primary producers) and organic extractive (bivalves) species in Integrated MultiTrophic Aquaculture (IMTA) create a balanced system with higher profitability and risk reduction. To achieve this, it is crucial to understand the role of each functional groups within the system what we did by comparing three different IMTA production three different IMTA production treatments with distinct combinations of trophic levels: •fish, filter feeders, phytoplankton and macroalgae,•fish, filter feeders and phytoplankton•fish, phytoplankton and macroalgae Each treatment was carried out in two similar ponds under semi-intensive conditions and flow through system, in a total of 6 earthen ponds of 500 m2 surface and depth of 1.5 m. Results showed that the presence of oysters in the ponds enhanced water quality by decreasing turbidity and by controlling phytoplankton which led to regulation of dissolved oxygen levels. The enhanced water quality in these systems lead to improved fish performance and higher biomass production contributing to greater profitability. The combination of fish, oyster, phytoplankton and macroalgae was particularly good providing much more fish supply compared with the other two treatments. •Oysters enhanced water quality in the ponds by decreasing turbidity and controlling phytoplankton which regulated the dissolved oxygen levels.•The enhanced water quality in systems with oysters improve fish performance resulting in higher biomass production and greater profitability.•The combination of fish, oyster, phytoplankton and macroalgae was particularly good providing much more fish supply compared with the other two treatments.