Isolation and fatty acid profile of selected microalgae strains from the Red Sea for biofuel production

The isolation of lipid-rich autochthonous strains of microalgae is a crucial stage for the development of a microalgae-based biofuel production plant, as these microalgae already have the necessary adaptations to withstand competition, predation and the temperatures observed at each production site. This is particularly important in extreme climates such as in Saudi Arabia. Resorting to fluorescence activated cell sorting (FACS) we screened for and isolated several microalgal strains from samples collected from the Red Sea. Relying on the fluorescence of BODIPY 505/515 (4,4-difluoro-1,3,5,7-tetramethyl-4-bora-3a,4a-diazasindacene) and growth performance, four promising candidates were identified and the total lipid content and fatty acid profile was assessed for biofuels production. Selected isolates were classified as chlorophytes, belonging to three different genera: Picochlorum, Nannochloris and Desmochloris. The lipid contents were assessed microscopically by means of BODIPY 505/515-associated fluorescence to detect intracellular lipid bodies, which revealed several lipid drops in all selected strains. This result was confirmed by lipid gravimetric determination, which demonstrated that all strains under study presented inner cell lipid contents ranging from 20% to 25% of the biomass dry weight. Furthermore, the fatty acid methyl esters profile of all strains seems ideal for biodiesel production due to a low degree of polyunsaturated fatty acid methyl esters and high amount of palmitic and oleic acids.NPST Program of King Saud University [11-ENE1719-02]info:eu-repo/semantics/publishedVersio

Macrobenthic response to sewage discharges in confined areas from coastal lagoons: implication on the ecological quality status

We studied the effect of wastewater on macrobenthic assemblages and local Ecological Quality Status (EcoQS) along a pollution gradient. The study consisted of six sampling sites surrounding the discharge channel of a Wastewater Treatment Plant located within Ria Formosa coastal lagoon. The total number of individuals was significantly higher at the discharge point comparatively to the control site, while total number of species, species richness and diversity values revealed the opposite pattern. Deposit-feeding were the most abundant trophic group, particularly at the inner sites, while the highest contributions of suspension-feeding and carnivory groups were observed at external ones. The organic matter content was positively correlated with the deposit-feeding group conferring a structural character of this variable near the plant discharge. M-AMBI index was consistent with the ANOSIM and SIMPER analysis, successfully separating the sampling stations according to the distance from the discharge and distinguishing the lower EcoQS of the inner sites not complying with the requirements of the Water Framework Directive of a “Good” quality status. In addition, changes in ecological and biotic indices were negatively correlated with variations of organic matter and positively correlated with salinity, corroborating the effect of these variables on the composition and structure of macrobenthic communities

First Impact Assessment of Genotoxic Components in the Qatari Marine Environment

The Arabian Gulf is a semi-enclosed sea with very high evaporation and low discharge rates resulting in extreme saline and thermal conditions. Additionally the system is characterized by a weak hydrodynamic flushing resulting in pollutant build-up over time. As a result, compared to open marine systems, added stress imposed by pollutants is likely to have severe consequences. Qatar has witnessed a rapid expansion in coastal development, linked to its industrial and population growth in recent decades. While economically and socially valuable, the growth comes with an associated environmental cost and Qatar's marine environment now faces many pressures including eutrophication, inputs of domestic sewage, discharge of industrial waste and the resuspension of sediment due to coastal construction. Although the threats pose to biota inhabiting Qatar's marine environment are evident, their extent has yet to be fully assessed. A large percentage of contaminants in the aquatic environment consist of potentially (directly or indirectly) genotoxic, carcinogenic and mutagenic substances. A genotoxin can modify the genetic material at non lethal and non cytotoxic concentrations and has often belated effects which are significantly important at the population and community levels. Genotoxins have particularly high ecotoxicological relevance in situations of chronic exposure to low doses and to multiple contaminants (e.g. in case of PAHs rich tarballs arriving in the shorelines), raising he need to establish genotoxicological profiles of the ecosystems. Indeed several regulatory developments such as: EU - Marine Strategy Framework Directive, the or US - Environmental Protection Agency - Integrated Risk Information System have stressed explicitly on the need of the detection and assessment of potential carcinogenic and mutagenic toxicants using genotoxicity endpoints. The analysis of cytogenetic endpoints in organisms exposed to contaminants in their natural environment contributes significantly to the early detection of genotoxic damage. The relevance of cytogenetic parameters and atypical cytogenetic features, such as numerical chromosomal abnormalities, i.e. aneuploidy, have largely proven their relevance as alerting indicators of poor environmental health and relevant biomarkers for the early detection of environmental stressors. The use of marine invertebrates for in situ environmental assessment is a widely accepted method for identifying risks to the ecosystems. Moreover, at the DNA and chromosome levels they express qualitatively similar types of induced damage to that found in higher organism (e.g. numerical and structural chromosomal aberrations). In this study, we aimed to take a step towards Qatar's marine sustainability by assessing the health status of the marine environment, and providing early alerting symptoms of degradation, by having as specific objectives: i) to measure the levels, in abiotic (water, sediments) and a marine invertebrate model species, of various anthropogenic contaminants (metals, polycyclic aromatic hydrocarbons, (PAHs) and Total polyaromatic hydrocarbons (TPH) at 3 selected sites around the Qatari coast, ii) measure the biological response at the chromosome level, and iii) determine the main drivers of genotoxicity through a multivariate analysis in order to establish a first partial genotoxicological profile of the Qatar Marine Zone. The 3 selected sampling sites, with expected different levels and sources of pollution were: South of Al Khor, Al Wakra harbor and South of Doha harbor. Two sampling campaigns were performed, one in summer and one in winter, to evaluate the role of the abiotic parameters, among others, on the bioavailability of the studied contaminants. The native pearl oyster Pinctada radiata was selected as model and surrogate species due to, its wide distribution along the Qatari coast, filter feeder and sessile mode of life and to its ability as a bivalve to bioaccumulate pollutants. Chemical analyses of the main trace metals and hydrocarbons were performed in water, sediment and P. radiata samples. The evaluation of the aneuploidy levels in P. radiata was estimated in 25-30 animals from each sampling site and season, by counting the total number of aneuploid metaphases over 30 metaphases counted per individual. The evaluation of the aneuploidy level on Pinctada radiata from the three sampling sites revealed an occurrence of significantly higher levels in Al-Wakra harbor (17% in summer and 20% in winter) and South of Doha harbor (19% in summer and 17% in winter), when compared to Al Khor (5% in summer cand 7% in winter). No statistically significant differences were observed between seasons in each location. In order to investigate the discrepancy between sampling sites and seasons with respect to all estimated descriptors and to evaluate the relationship between all the studied parameters, a principal component analysis (PCA) was performed. Aneuploidy levels were highly correlated to mercury and PAHs levels in the bivalve tissue. Moreover, the higher aneuploidy levels registered at Al Wakra harbor (both seasons) and Doha harbor (summer) showed a high correlation with the contaminants levels in P. radiata tissues. South of Al Khor (in both sampling seasons) was highly positively correlated with Cadmium (Cd), although this contamination was not responsible for a significant increase of the aneuploidy levels. The studied genotoxic contaminants were found to be highly variable among considered locations and between sampling seasons. Indeed, the 6 observations (contaminants levels among three sampling sites at two sampling seasons) differ substantially, no site or sampling season grouping being observed, which suggests an important spatial and temporal variability of the bioaccumulation of pollutants into P. radiata tissues. The aneuploidy levels, however, were consistently different among sampled locations, but did not differ between the two sampling seasons, suggesting that aneuploidy is the consequence of a local chronic contamination, and not a direct response to the temporal variability of the contaminants in P. radiata tissues. The results of this study confirm the suitability of the cytogenetic endpoints to discriminate, categorize the studied sites as regards to their level of contamination, underlining the added value of the detection of the genotoxicity levels in the marine environment to environmental health assessment and mitigation research programs. Further studies should be developed, under the specific hydrological and toxicological conditions of the Qatar Marine Zone (QMZ), to better explain the underlining mechanisms of such genotoxicity in the local filter feeders. The establishment of a Genotoxicological profile of the QMZ would be a valuable contribution to a wider approach on environmental diagnosis or prognosis, contributing to the protection and sustainability of the QMZ natural habitats and resources.qscienc

Towards Better Surveillance for Coral Ecosystems in Qatar: Stakeholder Engagement in EBM Approach.

More recently, Qatar has undergone a remarkable social and economic transformation in less than a generation. Although Qataris have a historic connection to the sea, dating back to the pearl diving days in the 19th century, the marine environment requires many interventions to be managed in a sustainable manner. Given the fact that coral reefs play an important role in the coastal ecosystem in this peninsular state, principles of environment sustainability should be undertaken for this significant habitats along the Qatari shores. Local pressures and climate change are among the most important factors that have negatively affected Qatar's coral communities. Other major threats result largely from human activities. To achieve sustainable development that preserves the Environment is a core goal especially included in all recent development regimes in Qatar. A balance between development needs and protecting the environment represents the fourth pillar of Qatar National Vision 2030. An explicit reference is also documented in the two most recently adopted strategies of development. This study introduces a good opportunity for Qatar to position itself as a regional leader in the use of environmental management systems that integrate multiple partners in guiding and conserving coral reefs as part of valuable ecosystems as a right of future generations of Qatari nationals guaranteed by the country's sustainable development agenda. It defines 4-stage engagement framework that include 9 diverse stakeholders proposed to participate in the management of coral reef ecosystems, therefore, facilitate monitoring and enforcement, enhance understanding of system dynamics, improve management capacity to respond to shocks and disturbances, and facilitate teamwork.This publication was made possible by the NPRP award [NPRP8-952-1-186] from the Qatar National Research Fund (a member of The Qatar Foundation) through the National Priority Research Program

International Centre for Coastal Ecohydrology: applying the ecohydrology approach for the sustainable functioning of coastal ecosystems

Coastal areas are among the most sensitive and productive ecosystems around the world, providing for the subsistence of large numbers of people, particularly in developing countries. Human pressure on coastal areas has dramatically increased during the last decades and climate changes will pose new threats to these areas, as expected from sea-level rise and the decrease in freshwater discharges from rivers (Chicharo et al., 2009). The International Centre for Coastal Ecohydrology (ICCE) a newly approved centre under the auspices of UNESCO, in October 2009, is located in the Algarve region (south Portugal). The centre acts as a facilitator and synergetic structure by providing the articulation of different scientific and institutional stakeholders at national and international levels. ICCE aims are to contribute scientific knowledge, capacity-building, educational and dissemination activities to support, design and implement adaptation and mitigation strategies and policies for coastal zones, including the impacts of climate change, addressing the goals of the Strategic Plan of the 7th Phase of UNESCO-IHP, the Millennium Development Goals (UN-MDGs) and the key themes for the United Nations Decade of Education for Sustainable Development (UN-DESD), particularly in African and Mediterranean regions.info:eu-repo/semantics/publishedVersio

Horizontal spatial and temporal distribution patterns of nearshore larval fish assemblages at a temperate rocky shore

There have been no previous studies of the composition of nearshore larval fish assemblages along the coast of Portugal. We aimed to describe the composition and horizontal distribution patterns of larval fish assemblages and their temporal dynamics near a rocky reef at depths shallower than 13 m (inshore) and at two miles (3.70 km) from shore (offshore), as well as along transects perpendicular to the shoreline, from the reef to 10 miles offshore (18.52 km). Samples were taken using 5 min sub-surface trawls at the rocky shore of the Arra´bida Marine Park (W Portugal). A total of 1021 larvae were collected, belonging to 61 taxa inshore and to 29 taxa offshore. Along transects, 626 larvae of 52 taxa were collected. Most larvae belonged to coastal species associated with rocky reefs. Total larval abundance and diversity were higher from May to July, which is consistent with the spawning activity of adults. Diversity and total larval abundance decreased significantly with increasing distance from shore, both in the inshore/offshore comparison and in the transects, where this decrease was evident at a very small spatial scale (within the first mile from the reef). Species assemblages differed in the pattern of distribution, with most species clearly associated to the extreme nearshore. The distribution patterns obtained were independent of the spawning mode of species. Results are discussed in the light of the possible physical mechanisms that can potentially act at the Arra´bida Marine Park to facilitate larvae retention and the role of larval behaviour

Biological activities and chemical composition of methanolic extracts of selected Autochthonous microalgae strains from the Red Sea

Four lipid-rich microalgal species from the Red Sea belonging to three different genera (Nannochloris, Picochlorum and Desmochloris), previously isolated as novel biodiesel feedstocks, were bioprospected for high-value, bioactive molecules. Methanol extracts were thus prepared from freeze-dried biomass and screened for different biological activities. Nannochloris sp. SBL1 and Desmochloris sp. SBL3 had the highest radical scavenging activity against 1,1-diphenyl-2-picrylhydrazyl, and the best copper and iron chelating activities. All species had potent butyrylcholinesterase inhibitory activity (>50%) and mildly inhibited tyrosinase. Picochlorum sp. SBL2 and Nannochloris sp. SBL4 extracts significantly reduced the viability of tumoral (HepG2 and HeLa) cells with lower toxicity against the non-tumoral murine stromal (S17) cells. Nannochloris sp. SBL1 significantly reduced the viability of Leishmania infantum down to 62% (250 mu g/mL). Picochlorum sp. SBL2 had the highest total phenolic content, the major phenolic compounds identified being salicylic, coumaric and gallic acids. Neoxanthin, violaxanthin, zeaxanthin, lutein and -carotene were identified in the extracts of all strains, while canthaxanthin was only identified in Picochlorum sp. SBL2. Taken together, these results strongly suggest that the microalgae included in this work could be used as sources of added-value products that could be used to upgrade the final biomass value.National Science, Technology and Innovation Program of King Abdulaziz Medical City for Science and Technology, Riyadh, Saudi Arabia [NPST, 11-ENE 1719-02]; Foundation for Science and Technology (FCT), Portugal [SFRH/BD/78062/2011]; FCT [IF/00049/2012, SFRH/BPD/86071/2012, Pest-OE/QUI/UI0612/2013]info:eu-repo/semantics/publishedVersio

Environmental factors affecting larval fish community in the salt marsh area of Guadiana estuary (Algarve, Portugal)

Salt marsh areas in the Guadiana estuary are important nursery sites for many fish species of commercial and recreational value. More effective protection measures should be adopted as the area is highly affected by anthropogenic and natural threats. Studying larval fish communities in these impacted nursery areas will be relevant to the management of local ecosystems and to larval fish ecology in general. Spatial and seasonal distribution and the effect of environmental factors on the larval fish community of this ecosystem were studied for one year (April 2010 to March 2011). Larvae were sampled monthly in parallel with phytoplankton and zooplankton. Hydrological data and physical parameters were monitored. A decision tree model was used to assess the influence of environmental factors on the larval fish community. A total of 130 larvae and 1171 eggs were caught. Diplodus sargus, Sardina pilchardus, and Pomatoschistus microps were the most abundant larval fish species. The peaks of fish larvae abundance occurred in March and April. The output of the model demonstrates that the abundance of larval fish is determined by the abundance of eggs, zooplanktonic food, and water flood and flow. This study shows the importance of the Guadiana salt marsh as an area for fish nursery and highlights the need for conservation of this area.FCT (Portuguese Foundation for Science and Technology) [SFRH/BD/47985/2008

Rebuilding viable spawner patches of the overfished Spisula solida (Mollusca : Bivalvia): a preliminary contribution to fishery sustainability

Populations of commercially important bivalves along the coast of Portugal are depleted as a consequence of natural and anthropogenic causes. A pilot experiment was designed to determine the feasibility of transplanting individuals from natural clam beds to a closed fishing area in an effort to rebuild relatively high-density patches of Spisula solida. For this purpose, clams were equally partitioned into two groups (undersize and legal clams) and transplanted at a density of 40 clams m(-2) into two areas 50 m(2). Transplanted and control clams were sampled to estimate survival, condition index, biochemical composition, and reproductive condition. Generally, the physiological condition of clams was not affected by the method of transplanting. One year after transplanting, survival was 45%. The increase in local abundance of mature clams should facilitate successful fertilization and increase the residual reproductive value of each clam relative to its pre-transplant value. Transplanting undersize clams may be more advantageous because they are more likely to spawn at least once before harvest. The experiments demonstrate that spawner transplants may strengthen S. solida populations and can be used in stock-enhancement programmes which, in conjunction with effective management measures, can contribute to the sustainability of the S. solida fishery.info:eu-repo/semantics/publishedVersio

Alternative sources of n-3 long-chain polyunsaturated fatty acids in marine microalgae

The main source of n-3 long-chain polyunsaturated fatty acids (LC-PUFA) in human nutrition is currently seafood, especially oily fish. Nonetheless, due to cultural or individual preferences, convenience, geographic location, or awareness of risks associated to fatty fish consumption, the intake of fatty fish is far from supplying the recommended dietary levels. The end result observed in most western countries is not only a low supply of n-3 LC-PUFA, but also an unbalance towards the intake of n-6 fatty acids, resulting mostly from the consumption of vegetable oils. Awareness of the benefits of LC-PUFA in human health has led to the use of fish oils as food supplements. However, there is a need to explore alternatives sources of LC-PUFA, especially those of microbial origin. Microalgae species with potential to accumulate lipids in high amounts and to present elevated levels of n-3 LC-PUFA are known in marine phytoplankton. This review focuses on sources of n-3 LC-PUFA, namely eicosapentaenoic and docosahexaenoic acids, in marine microalgae, as alternatives to fish oils. Based on current literature, examples of marketed products and potentially new species for commercial exploitation are presented.NPST Program of King Saud University [11-ENE1719-02]; SEABIOMED [PTDC/MAR/103957/2008]; Foundation for Science and Technology (FCT); Portuguese National Budgetinfo:eu-repo/semantics/publishedVersio