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- Opuntia ficus indica waste as a cost effective carbon source for lactic acid production by Lactobacillus plantarumPublication . Derabli, Besma; Nancib, Aicha; Nancib, Nabil; Aníbal, Jaime; Raposo, Sara; Rodrigues, Brígida; Boudrant, JosephOpuntia ficus indica (OFI) waste was evaluated as a fermentation feedstock for lactic acid production using Lactobacillus plantarum. Dilute acid pretreatment of the OFI cladodes (OFIC) was performed for extracting maximum fermentable sugars by optimizing process parameters using statistical optimization method. The best results were obtained with HCl 1% (v/v), temperature 120 ◦C, residence time 40 min, granulation 350 μm and substrate loading 5% (w/v), the sugar concentration reached 24 g/L with low concentration of hydroxymethylfurfural. The feasibility of producing lactic acid from OFI fruit peel (OFIFP) as a source of carbon was also investigated. Lactobacillus plantarum was shown to have a capacity for lactic acid production from OFIC350 (granulation 350 μm) hydrolysate and OFIFP extract without detoxification. The highest lactic acid yields of 0.46 and 0.78 g/g were obtained from enzymatic hydrolysate of pretreated OFIC350 and OFIFP extract, respectively.
- Sarcocornia fruticosa and Spartina maritima as heavy metals remediators in an European southwestern salt marsh (Ria Formosa, Portugal)Publication . F. G. M. Silva, Manuela; Aníbal, J.; Duarte, Duarte; Chícharo, LuísSalt marshes are transition zones between land and sea, exposed to several sources of different pollutants, including heavy metals, which tend to be accumulated in sediments. Halophyte vegetation which colonises sediments affects retention and biovailability of the pollutants that reach salt marsh areas. The accumulation capacity and the pattern of metal distribution in salt marsh plant tissues vary among plant species, and with sediment characteristics. The aim of this study was to survey the behaviour of Spartina maritima and Sarcocornia fruticosa on heavy metals contents and distribution amongst sediment and plant tissues in an European Southwestern lagoon (Ria Formosa, Portugal). Both species could fix metals from the surrounding belowground environment and accumulate them mainly in roots (and in rhizomes for S. maritima). Metal translocation to aerial organs was residual. S. maritima acted as a more effective metal stabiliser than S. fruticosa.
- Nitrate reductase activity in green macroalgae as an environmental indicator of temperature and salinity changes and its implication for climate change projectionsPublication . Madeira, Hélder T.; Aníbal, Jaime; Carvalho, Liliana F.; Esteves, Eduardo; Veiga-Pires, C.Temperature and salinity changes can affect nutrient assimilation dynamics in primary producers. Green macroalgae use nitrate as a main source of nitrogen for their metabolism. Nitrate needs to be reduced by nitrate reductase, before amino acids synthesis. Our aims were to study the effect of temperature and salinity changes on nitrate reductase activity (NRA) in Ulva rigida and Enteromorpha clathrata, and to assess if this enzyme can be used as an environmental indicator for changes in such abiotic factors. The study of NRA was carried out using potassium nitrate as substrate and propanol as a membrane permeabilizer, letting the produced nitrite to exit the macroalgae cells into the assay medium, allowing its quantification through a colorimetric method. This procedure was carried out at five temperatures (10, 20, 30, 35 and 40 °C) and three salinities of the assay medium (0, 15 and 36 g/kg). Results show that both Ulva and Enteromorpha have maximum NRA at salinities of 36 g/kg, although nitrate reduction can occur in freshwater or brackish water, but at significantly lower rates. NRA varied significantly with temperature for both macroalgae, although Ulva showed maximum NRA at 30 °C, while NRA peaked at 35 °C in Enteromorpha. Likely adequate models were tentatively fitted to NRAtemperature data at different salinities. NRA is a suitable proxy of the effects of temperature and salinity changes on the ability of green macroalgae to uptake and metabolize nitrogen nutrients and can thus be the base for macroalgae proliferation models under climate change model scenarios.
- Pegada ecológica da alimentaçãoPublication . Fernandes, Jacinta; Aníbal, J.Alimentação é uma das partes mais importantes do quotidiano humano, garante da sobrevivência, função de padrões culturais e estilos de vida? Pegada Ecológica constitui uma forma de medir o impacte humano na Terra. Conceito desenvolvido por M. Wackernagel e W. Rees, 1996
- A importância da avaliação sensorial da qualidade do pescadoPublication . Esteves, E.; Aníbal, J.Globalmente, a pesca é uma indústria que movimenta milhares de milhões de euros por ano (as importações e exportações de produtos da pesca atingiram, em 2005, cerca 82 mil milhões de euros e 78 mil milhões de euros, respectivamente, dados da FAO – Food and Agriculture Organization das Nações Unidas).
- Fish ultrasonography characterization of cardiac morphology and blood flowPublication . Coucelo, Josefina; Joaquim, N.; Aníbal, J.; Coucelo, JosefinaNon invasive identification and characterization of cardiac morphology and flow of Lophius s.p. and Halobactrachius s.p. was performed using color echo doppler. We used an ALOKA echo camera SSD 830 with a 5 MHZ transducer. Fishes were kept alive with water circulation device. The transducer was applied in the ventral middle line over heart chambers. Bidimensional images were obtained from long and short axis incidences at various levels of cardiac chambers. During each cardiac cycle and for every specimen it was possible to identify the relationship between each structure, measure longitudinal and transversal diameters, identify blood ?uxes and quantify their velocities. Conclusion: In live specimens it is possible, applying non invasive techniques, to observe the cardiac structures and to study the kinetic of the ventricle and bulbus, to identify blood ?ow and to measure his velocity. This can be used as an experimental model for cardiac function.
- Seasonal variations in gross biochemical composition, percent edibility, and condition index of the clam Ruditapes Decussatus cultivated in the Ria Formosa (South Portugal)Publication . Aníbal, J.; Esteves, E.; Rocha, C.The grooved carpet shell clam, Ruditapes decussatus (L. 1758), is one of the most popular and profitable molluscs exploited in rearing plots in the Mediterranean. However, annual catch has been declining steadily since the early nineties. In order to understand the seasonality of its nutritional value, thus providing an improved basis for economical valuation of the resource, gross biochemical composition, percentage edibility and condition index were investigated during a year with monthly periodicity in a commercially exploited population of the clam Ruditapes decussatus in the Ria Formosa, a temperate mesotidal coastal lagoon located in the south of Portugal. Our results show that total and non-protein nitrogen co-varied during the year, resulting in a protein content that peaked in the warmest months. Although complementary in summer, carbohydrate and lipid contents showed irregular annual trends. The observed seasonality was comparable to that shown by studies elsewhere at similar latitudes, and are underpinned by the reproductive cycle of the species. Our results show the clams to be at their prime nutritional value at the beginning of summer, when protein content peaks.
- Mudflat surface morphology as a structuring agent of algae and associated macroepifauna communities: a case study in the Ria FormosaPublication . Aníbal, J.; Rocha, C.; Sprung, MartinAlthough mudflats seem relatively planar, closer inspection reveals a succession of meso-topographical features, including consecutive convex and concave meso- and micro-topographical features. The objective of this study was to determine the influence of meso-scale surface sediment morphology on the dynamics of the macroalgae Ulvales (Chlorophyta) and associated macroepifauna in the Ria Formosa tidal lagoon (southern coast of Portugal). Four sites in the Ria Formosa were sampled monthly. Two were located on convex sections (mounds) of the mudflat and the other two on concave sections (depressions). Macroalgae and related macroepifauna were sampled at each station. Biomass was quantified by determination of the ash-free dry weight (AFDW). Data were analysed using the software package ‘PRIMER’ (Plymouth Routines In Multivariate Ecological Research). Results show a clear distinction between convex and concave areas. In convex sections, Enteromorpha dominated, to the point of being the only algal species present during part of the year. Conversely, biomass and dynamics of Enteromorpha and Ulva were almost the same in concave sections. The associated macroepifauna was also different in protruding or depressed sections of the mudflat. In the convex areas, the macroepifauna population showed less diversity and was dominated by the snail Hydrobia ulvae. In concave areas, the species diversity was larger, but dominated in terms of biomass by the amphipod Melita palmata and the gastropod Nassarius pfeifferi. Results of the study indicate that the benthic communities associated with concave or convex features were different. No relevant differences in texture and sediment physico-chemical characteristics were found between convex and concave sections. The inference is that the morphological nature of the bottom in tidal mudflats can act as a structuring agent of benthic communities.
- Hydroiid snails conditioning green algae mats (Enteromorpha spp.) in the Northern HemispherePublication . Schories, D.; Albrecht, A.; Aníbal, J.; Fletcher, R.; Isaksson, I.; Lillebo, A. I.; Pihl, L.; Pye, K.; Reise, K.; Sprung, Martin; Thiel, M.For the last decades dense mats of filamentous green algae Enteromorpha spp. have regularly occurred worldwide on tidal Àats. The development of green algal rnats on intertidal Àats is commonly achieved by overwintering and regrowth of adult plants or by the formation and detachment of propagules. Up to now the study of germlings as initiators of algal mats have received relatively little attention. It was known from one of our study sites (Konigshafen Bay, Germany) that shells of living mudsnails (Hydrobia ulvae) serve as the main substrate of overwintering Enteromorpha spores and initiate in this way extensive growth of Enteromorplza mats in spring. We investigated the presence of Enteromorpha germlings attached on hydrobiid snails in different places of Canada, England, Germany, Portugal, Sweden and the United States between November 1995 and November 1996. At all investigation sites huge amounts of hydrobiid snails were present during the last years and and intensive growth of Enteromorplm occurred during the course of the season. - During winter 1995 /96 hardly any Enteromorpha germlings were found on the snail houses, but depending on the site, germlings developed on up to 60 % of hydrobiid snails during spring. It is obvious, that at least in some areas the germling development was related to overwintering of spores on snails, due to poor biomass of adult Enteromorpha plants during winter. In our study we could demonstrate that hydrobiid snails can play an important role in soft sediments for the successfull development of green algal mats in soft sediments.
- Metals from human activities in a coastal Lagoon Saltmarsh - Sediment toxicity and phytoremediation by Sarcocornia fruticosaPublication . Silva, Manuela; Aníbal, Jaime; Duarte, D. N.; Veloso, N.; Patrício, F.; Chicharo, LuisAnthropogenic pressure on coastal areas has been increasing in the last decades, threating the saltmarshes and the ecosystem services they provide. Sarcocornia fruticosa can have an important role in sequestration of metals from human activities. This study evaluated the effect of metal toxicity in saltmarsh sediment (measured by Ecological Risk Index-ERI) on S. fruticosa ability to metal (Cd, Cr, Ni, Pb and Zn) remediation (Enrichment Factor and metal translocation). The impact of urbanization was studied through the metal loads on stormwaters during two main rainfall events, and the industrial impact was assessed through data analyses in a saltmarsh area influenced by a stream that receives industrial runoffs. The S. fruticosa response on metal remediation was affected by ERI. In more polluted locations, retained metals on roots and prevented the most toxic (Cd and Pb) from reaching the aerial organs, avoiding tissues death and metal remobilisation to the saltmarsh. Meanwhile, in rhizosediments with conditions to high metal bioavailability, S. fruticosa transported Cd and Pb to aerial organs, but used the Zn translocation to decrease their toxicity. This halophyte resilience is important to saltmarsh metal sequestration in high toxicity conditions, and allows the maintenance of other ecosystem services, contributing to the environmental protection and public health.