Carolina Bruno de Sousa

Fatty acid profile of different species of algae of the Cystoseira genus: a nutraceutical perspective.

The fatty acid (FA) composition of six macroalgae from the Cystoseira genus, namely Cystoseira compressa, Cystoseira humilis, Cystoseira tamariscifolia, Cystoseira nodicaulis, Cystoseira baccata and Cystoseira barbata, was determined. Polyunsaturated fatty acids (PUFA) corresponded to 29–46% of the total FA detected. C. compressa, C. tamariscifolia and C. nodicaulis stood out for their low PUFA/saturated fatty acid, low n-6 PUFA/n-3 PUFA ratios as well as favourable unsaturation, atherogenicity and thrombogenicity indices, suggesting a high nutritional value with potential applications in the nutraceutical industry.

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 µg/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 β-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.

Isolation of a euryhaline microalgal strain, Tetraselmis sp. CTP4, as a robust feedstock for biodiesel production

Bioprospecting for novel microalgal strains is key to improving the feasibility of microalgae-derived biodiesel production. Tetraselmis sp. CTP4 (Chlorophyta, Chlorodendrophyceae) was isolated using fluorescence activated cell sorting (FACS) in order to screen novel lipid-rich microalgae. CTP4 is a robust, euryhaline strain able to grow in seawater growth medium as well as in non-sterile urban wastewater. Because of its large cell size (9–22 μm), CTP4 settles down after a six-hour sedimentation step. This leads to a medium removal efficiency of 80%, allowing a significant decrease of biomass dewatering costs. Using a two-stage system, a 3-fold increase in lipid content (up to 33% of DW) and a 2-fold enhancement in lipid productivity (up to 52.1 mg L−1 d−1) were observed upon exposure to nutrient depletion for 7 days. The biodiesel synthesized from the lipids of CTP4 contained high levels of oleic acid (25.67% of total fatty acids content) and minor amounts of polyunsaturated fatty acids with ≥4 double bonds (<1%). As a result, this biofuel complies with most of the European (EN14214) and American (ASTM D6751) specifications, which commonly used microalgal feedstocks are usually unable to meet. In conclusion, Tetraselmis sp. CTP4 displays promising features as feedstock with lower downstream processing costs for biomass dewatering and biodiesel refining.

Can macroalgae provide promising anti-tumoral compounds? A closer look at Cystoseira tamariscifolia as a source for antioxidant and anti-hepatocarcinoma compounds

Marine organisms are a prolific source of drug leads in a variety of therapeutic areas. In the last few years, biomedical, pharmaceutical and nutraceutical industries have shown growing interest in novel compounds from marine organisms, including macroalgae. Cystoseira is a genus of Phaeophyceae (Fucales) macroalgae known to contain bioactive compounds. Organic extracts (hexane, diethyl ether, ethyl acetate and methanol extracts) from three Cystoseira species (C. humilis, C. tamariscifolia and C. usneoides) were evaluated for their total phenolic content, radical scavenging activity against 2,2-diphenyl-1-picrylhydrazyl (DPPH) and 2,2′-azino-bis(3-ethylbenzothiazoline-6-sulphonic acid) (ABTS) radicals, and antiproliferative activity against a human hepatocarcinoma cell line (HepG2 cells). C. tamariscifolia had the highest TPC and RSA. The hexane extract of C. tamariscifolia (CTH) had the highest cytotoxic activity (IC50 = 2.31 µg/mL), and was further tested in four human tumor (cervical adenocarcinoma HeLa; gastric adenocarcinoma AGS; colorectal adenocarcinoma HCT-15; neuroblastoma SH-SY5Y), and two non-tumor (murine bone marrow stroma S17 and human umbilical vein endothelial HUVEC) cell lines in order to determine its selectivity. CTH strongly reduced viability of all tumor cell lines, especially of HepG2 cells. Cytotoxicity was particularly selective for the latter cells with a selectivity index = 12.6 as compared to non-tumor cells. Incubation with CTH led to a 2-fold decrease of HepG2 cell proliferation as shown by the bromodeoxyuridine (BrdU) incorporation assay. CTH-treated HepG2 cells presented also pro-apoptotic features, such as increased Annexin V/propidium iodide (PI) binding and dose-dependent morphological alterations in DAPI-stained cells. Moreover, it had a noticeable disaggregating effect on 3D multicellular tumor spheroids. Demethoxy cystoketal chromane, a derivative of the meroditerpenoid cystoketal, was identified as the active compound in CTH and was shown to display selective in vitro cytotoxicity towards HepG2 cells.

Report of in vitro antileishmanial properties of Iberian macroalgae

Abstract Here is reported the anti Leishmania infantum activity of 48 hexane, CH2Cl2 and MeOH extracts from 16 macroalgae collected on the Iberian Coast. Seven hexane and CH2Cl2 Cystoseira baccata, Cystoseira barbata, Cystoseira tamariscifolia, Cystoseira usneoides, Dictyota spiralis and Plocamium cartilagineum extracts were active towards promastigotes (IC50 29.8–101.8 μg/mL) inducing strong morphological alterations in the parasites. Hexane extracts of C. baccata and C. barbata were also active against intracellular amastigotes (IC50 5.1 and 6.8 μg/mL, respectively). Fatty acids, triacylglycerols, carotenoids, steroids and meroterpenoids were detected by nuclear magnetic resonance (NMR), and gas chromatography in the Cystoseira extracts. These results suggest that Cystoseira macroalgae contain compounds with antileishmanial activity, which could be explored as scaffolds to the development of novel sources of antiparasitic derivatives.

Conservation of Goat Populations from Southwestern Europe Based on Molecular Diversity Criteria

Goat farming plays a key role in agricultural activity and in maintaining forest lands in Southwestern Europe. Remarkably, the Iberian Peninsula represents nearly 25% of the European goat census. Goat husbandry is often associated with low input production systems and uses selective breeding programs, which are less advanced than those employed in other livestock. Native goat breeds are very well adapted to produce in marginal areas under extensive conditions. Loss of their genetic diversity could have important economic, ecological and scientific implications as well as social consequences. Several methodologies have been developed to preserve the genetic diversity of single populations, but additional problems arise when a group of breeds, i.e., subpopulations, is considered in conservation programs. The conservation priority of a breed depends on its contribution to the overall genetic diversity of the species, in terms of the intrinsic genetic variation that it harbors and also of its relationship with other breeds. However, the estimation of the contributions of each of these two components to overall genetic diversity cannot be easily assessed. Besides, conservation goals in the short-term (avoidance of inbreeding) and long-term (adaptation to future environmental changes) should be considered when taking conservative decisions. A comprehensive analysis of Iberian goat breeds has been carried out to evaluate conservation priorities based on methodologies that account for within- or between-breed genetic diversity, or combinations of both. Based on genetic distinctiveness, breeds such as Palmera, Formentera, and Blanca Celtiberica were prioritized, whereas the maximum priority was assigned to Florida, Pirenaica, Retinta, and Moncaina breeds when focusing on within-breed diversity. Overall, combined approaches showed very little variation among breeds reflecting a history of extensive gene flow, partly due to transhumance and recent divergence. The main conclusion of our study is that these statistical analyses are useful, but conservation decisions must take into account other factors in addition to strict genetic diversity classification.

Aprender a ensinar: influências culturais no desenho artístico (estudo de caso)

Nesta era multicultural em que vivemos, e em que estamos cada vez mais proximos atraves da internet e dos meios de comunicacao, sofremos influencias culturais que outrora seriam impensaveis. No nosso meio, tem vindo a crescer varias expressoes artistico-visuais influenciadas por fenomenos de cultura visual ligadas a imagem, oriundos das mais diversas culturas. Este trabalho, inserido no campo da investigacao educativa, pretende analisar as influencias culturais presentes no desenho de um aluno do ensino secundario enquadrado na area das artes visuais. Para tal, a investigacao e realizada em Portugal, numa escola secundaria publica na regiao do Algarve, concretamente na cidade de Faro, e a escola caracteriza-se por estar ligada as artes plasticas, apresentando-se os dados recolhidos junto deste aluno na disciplina de desenho. Palavras-chave: Influencias culturais. Desenho artistico. Artes visuais. Educacao artistica. Cultura visual. Learning to teach: cultural influences in artistic drawing (case study) Abstract In this multicultural era in which we live, and the fact that we are increasingly united via the internet and the media, leads us to cultural influences that once were unthinkable. In our midst, several visual-artistic expressions have grown influenced by visual culture phenomena related to the image, originating from diverse cultures. This study, in the field of educational research, aims to examine the cultural influences present in the drawing of a secondary school student studying visual arts. To do so, research was made at a Portuguese public high school in the Algarve region, characterized by being an art school. Data collected from one case study, lead to the conclusions presented in this study. Keywords: Cultural influences. Artistic drawing. Visual arts. Art education. Visual culture.