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Diatoms are currently considered valuable feedstocks for different biotechnological applications. To deepen the knowledge on the production of these microalgae, the diel pattern of batch growth, photosystem II performance, and accumulation of target metabolites of two commercially relevant diatoms, Phaeodactylum tricornutum and Skeletonema costatum, were followed outdoors in 100-L flat panel photobioreactors. S. costatum presented a higher light-to-biomass conversion resulting in higher growth than P. tricornutum. Both fluorescence data and principal component analysis pointed to temperature as a limiting factor for the growth of P. tricornutum. Higher protein and carbohydrate contents were found in P. tricornutum, whereas S. costatum fatty acids were charac-terized by a higher unsaturation degree. Higher productivities were found at 1 p.m. for protein, lipid, and ash in the case of S. costatum. Overall, S. costatum showed great potential for outdoor cultivation, revealing a broader temperature tolerance and increased biomass productivity than P. tricornutum. info:eu-repo/semantics/publishedVersion

Senegalese sole (Solea senegalensis) production presents several nutritional challenges, making this species a good candidate to study the dietary potential of bioactive compounds. Since proper nutrition plays a fundamental role in fish biology, it is necessary to further investigate species-specific and well-balanced diets in order to improve Senegalese sole juvenile farming. Algae have antioxidant properties, high-quality dietary protein, and are a source of bioactive compounds. This study evaluates the effects of dietary microalgal inclusion in both health status and growth performance of Senegalese sole post-larvae. Individuals 41 days after hatching (DAH) were randomly distributed among 12 tanks and four experimental diets were randomly distributed by triplicate groups. A basal diet served as CTRL and the experimental diets were formulated to include 3% of each of the algal biomass (CHLO, Chlorella sp. from heterotrophic production; PHAEO, Phaeodactylum sp.; and NANNO, Nannochloropsis sp.). At 50 DAH, 20 post-larvae/tank were collected and homogenized for analysis of immune and oxidative status, and at 61 DAH the total length, dry weight, and survival were assessed. No changes were observed in survival and total length of individuals, post-larvae fed NANNO, and CHLO dietary treatments increased dry weight at 61 DAH compared with those fed CTRL. While post-larvae immune status was apparently not altered by dietary treatments at 50 DAH, the total glutathione content decreased in fish fed PHAEO and CHLO dietary treatments compared to control diet. The observed results on improvement of growth performance without adverse effects on the immune status and decrease of endogenous total glutathione point to the fact that Nannochloropsis sp., Phaeodactylum sp., and Chlorella sp. could work as potential candidates for inclusion in microdiets for Senegalese sole. VALORMAR project - Compete 2020 [POCI-01-0247-FEDER-024517]; Lisboa 2020; CRESC Algarve 2020; Portugal 2020; European Union through European Regional Development Fund; Foundation for Science and Technology (FCT)Portuguese Foundation for Science and TechnologyEuropean Commission [UIDB/04423/2020, UIDP/04423/2020]; FCT, PortugalPortuguese Foundation for Science and TechnologyEuropean Commission [SFRH/BD/108243/2015, PD/BDE/129262/2017, IF/00197/2015] info:eu-repo/semantics/publishedVersion

Fucoxanthin is a xanthophyll carotenoid with high market value. Currently, seaweeds are the primary source for fucoxanthin industrial production. However, marine microalgae reach 5 to 10 times higher concentrations (2.24 to 26.6 mg g-1 DW) and are considered a promising feedstock. In this work, two marine microalgae were produced at industrial scale to evaluate biomass and fucoxanthin production: Phaeodactylum tricornutum for autumn/winter and Tisochrysis lutea for spring/summer. Both strains were grown in 15 m3 tubular flow-through photobioreactors; for 170 consecutive days of semi-continuous cultivation regime. The average volumetric biomass productivities of P. tricornutum and T. lutea were 0.11 and 0.09 g DW L-1 day-1. P. tricornutum reached higher maximum biomass concentration (2.87 g DW L-1) than T. lutea (1.47 g DW L-1). P. tricornutum fucoxanthin content ranged between 0.2 and 0.7% DW, while T. lutea between 0.2 and 0.6% DW. The fucoxanthin content was correlated with the irradiation (MJ m-2) and biomass concentration in the photobioreactor (g L-1). This is the first work in literature reporting a long-term industrial production of T. lutea. Overall, we showed possible scenarios for fucoxanthin production from microalgae, increasing the window to supply the industry with steady production throughout the year. info:eu-repo/semantics/publishedVersion

Microalgal biomasses are known to play a major role in fish pigmentation, which is particularly important in farmed fish, since colour and external appearance are the first cue for customers when choosing seafood. A study was undertaken to assess the potential of microalgae biomass from the diatom Phaeodactylum tricornutum as a functional ingredient for gilthead seabream (Sparus aurata) feeds. Three experimental diets were designed: a control diet (CTRL), this same diet supplemented with 2.5% of P. tricornutum wild strain (diet MA20); and a third diet with 2.5% of P. tricornutum biomass (diet MA37) cultivated under different temperature and light regimes that resulted in higher levels of fucoxanthin. Microalgae diets led to a reduction (P < 0.05 in MA37) of whole-body fat and lower lipid retention (P < 0.05 in MA20 and MA37). Microalgae did not impact odour, flavour, whiteness, and fatness perception in cooked fillets. Overall, colour analysis showed that P. tricornutum biomass led to significant differences compared to control in specific areas: the MA37 diet induced a significantly (P < 0.05) lighter and more vivid yellow colouration of seabream operculum (Delta E* approximate to 5) perceptible to the human eye; ventral skin lightness was also affected by the dietary treatments (P = 0.040), being higher for microalgae-fed groups, though this difference was not perceptually strong (Delta E* approximate to 1.7). Phaeodactylum tricornutum biomass can be used as a functional ingredient, improving external pigmentation and thus contributing to meet consumer expectations in relation to farmed gilthead seabream. EU FP7 [266401] FCT/MCTES (Portugal) through grant [SFRH/BD/73452/2010] info:eu-repo/semantics/publishedVersion

Large-scale cultivation of Chlorella vulgaris is of great interest given the extent of products and potential applications that can derive from its biomass. From an industrial point of view it is imperative to consistently obtain high productivities and high quality biomass at the lowest production costs. The mass balance of critical nutrients such as carbon and nitrogen is therefore necessary to quantify its recovery and consumption yields, the efficiency of the biomass production system and to identify operational optimization opportunities. The mass balance of C. vulgaris mixotrophic growth throughout scale-up from 10 m 3 to 100 m 3 on acetate and urea as carbon and nitrogen sources was calculated using a black-box model developed to illustrate the inputs and outputs of the system in quasi - real time and resulted on recovery factors of 0.99 ± 0.08 and 0.99 ± 0.25, respectively. Under these conditions C. vulgaris cultivation yielded a maximal productivity of 0.14 g L − 1 d − 1 and maximal growth rate of 0.38 d − 1 . Both parameters decreased throughout scale up reaching an average productivity of 0.09 g L − 1 d − 1 with an average growth rate of 0.13 d − 1 for the whole process. Global carbon and nitrogen yields measured were 0.76 mol C-X mol C − 1 and 0.72 mol N-X mol N − 1 . The mass balance determination indicates the incorporation of both acetate and urea carbon atoms into the biomass. Therefore, external inorganic carbon from CO 2 was concluded to have little influence on microalgae growth in the conditions studied apart from pH control. Urea and ammonium were found to be effectively used by C. vulgaris cells. However, despite the satisfactory yield obtained for nitrogen, the metabolism of urea resulted in ammonium build-up in the culture medium. To our knowledge this is the first report of growth parameters and mass balance analysis of a Chlorella sp. culture in industrial scale closed tubular photobioreactors.

ALGAFARM is an industrial-scale microalgae production facility for the production of Chlorella biomass for food and feed applications. ALGAFARM integrates the entire production process, from small-volume production at a lab scale to final product packaging. It uses a combination of closed photobioreactor (PBR) technologies comprising mainly of large modular arrays of tubular PBRs (Figure 13.1) to cultivate the microalgae. The closed modular PBRs are based on transparent plastic

The world annual production of rice is higher than 700.7 million tons, which generates rice husk and straw wastes. Rice culture also produces big amounts of polyethylene (PE) bags used in rice packs and for seeds and fertilizer storage that usually end up in landfills, due to their degree of contamination. The energetic valorisation of these wastes may be accomplished by different processes, co-gasification is one of the most viable, as it leads to the production of a synthetic gaseous mixture (bio-syngas) that can be used for energy production to be used during rice milling processes. Gasification of rice husks has some challenges, due to these wastes high content of silica and alkali metals that lead to the formation of solids with lower melting point, thus, leading to bed agglomeration that causes reactor erosion and serious damage. PE has lower ash content and much higher energetic content than rice husks. However, PE polymeric structure may lead to the formation of higher tar contents, which compromise most gasification gas utilisations. Co-gasification of PE and rice husks allows taking advantages of each waste favourable characteristic, diluting the unsuitable features. Co-gasification of these wastes was done in presence of steam blended with air or oxygen. Steam promoted the gasification reactions and favoured H2 production. Air or oxygen promoted the partial oxidation of the feedstocks to be co-gasified and supplied the energy necessary for the endothermic gasification reactions. The use of air has a low cost, but has the great disadvantage of diluting the bio-syngas produced, thus lowering its energetic content. On the other hand, the use of oxygen solves the problems related to gas dilution with nitrogen, but increases the operating cost. Bio-syngas composition obtained by co-gasification trials done with air enriched with different oxygen contents was compared with those obtained with air or pure oxygen to determine the best approach considering both the technical and economical sustainability.

n the pulp and paper industry in Iberian Peninsula there is an intensive use of eucalyptus globulus that has a fast growth and a high productivity. There are large areas of forest dedicated to its growth. After 9 to 12 year rotation cycles trees are cut and the stumps are left in the fields. After 2 or 3 harvesting cycles these tree stumps are removed from the fields and considered low value biomass wastes. This corresponds to depletion on organic matter and of valuable minerals related to soil fertility. The use of these biomass wastes in thermochemical conversion processes like gasification or combustion may be a valuable alternative solution as it allows taking profit of these wastes energetic content. The solid by-products obtained by thermal conversion (ashes) may be incorporated in soils to return the valuable minerals and to ensure a good forest management system. Stumps removed from eucalyptus stands were used in combustion trials to improve the burning conditions and in gasification tests with different experimental conditions to obtain syngas suitable to be used in furnaces (chemical recover) of pulp industries. Stumps combustion and gasification processes were compared in terms of stumps energetic valorisation, gaseous emissions and gasification gas utilisation.

Trabalho Final de Mestrado Integrado, Ciências Farmacêuticas, Universidade de Lisboa, Faculdade de Farmácia, 2014 Submitted by Repositório FFUL (repositorio@ff.ul.pt) on 2016-12-30T17:48:11Z No. of bitstreams: 1 MICF_Maria_Joao_Nabais.pdf: 1234761 bytes, checksum: 75833197db028aa639f59f5e4f6087e8 (MD5) Made available in DSpace on 2017-01-04T17:35:20Z (GMT). No. of bitstreams: 1 MICF_Maria_Joao_Nabais.pdf: 1234761 bytes, checksum: 75833197db028aa639f59f5e4f6087e8 (MD5) Previous issue date: 2014