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- Cyanobacterial diversity held in microbial biological resource centers as a biotechnological asset: the case study of the newly established LEGE culture collectionPublication . Ramos, Vitor; Morais, João; Castelo-Branco, Raquel; Pinheiro, Ângela; Martins, Joana; Regueiras, Ana; Pereira, Ana L.; Lopes, Viviana R.; Frazão, Bárbara; Gomes, Dina; Moreira, Cristiana; Costa, Maria Sofia; Brûle, Sébastien; Faustino, Silvia; Martins, Rosario; Saker, Martin; Osswald, Joana; Leão, Pedro N.; Vasconcelos, Vitor M.Cyanobacteria are a well-known source of bioproducts which renders culturable strains a valuable resource for biotechnology purposes. We describe here the establishment of a cyanobacterial culture collection (CC) and present the first version of the strain catalog and its online database (http://lege.ciimar.up.pt/). The LEGE CC holds 386 strains, mainly collected in coastal (48%), estuarine (11%), and fresh (34%) water bodies, for the most part from Portugal (84%). By following the most recent taxonomic classification, LEGE CC strains were classified into at least 46 genera from six orders (41% belong to the Synechococcales), several of them are unique among the phylogenetic diversity of the cyanobacteria. For all strains, primary data were obtained and secondary data were surveyed and reviewed, which can be reached through the strain sheets either in the catalog or in the online database. An overview on the notable biodiversity of LEGE CC strains is showcased, including a searchable phylogenetic tree and images for all strains. With this work, 80% of the LEGE CC strains have now their 16S rRNA gene sequences deposited in GenBank. Also, based in primary data, it is demonstrated that several LEGE CC strains are a promising source of extracellular polymeric substances (EPS). Through a review of previously published data, it is exposed that LEGE CC strains have the potential or actual capacity to produce a variety of biotechnologically interesting compounds, including common cyanotoxins or unprecedented bioactive molecules. Phylogenetic diversity of LEGE CC strains does not entirely reflect chemodiversity. Further bioprospecting should, therefore, account for strain specificity of the valuable cyanobacterial holdings of LEGE CC.
- Isolation, characterization and quantification of microcystins (heptapeptides hepatotoxins) in Microcystis aeruginosa dominated bloom of Lalla Takerkoust lake–reservoir (Morocco)Publication . Martins, RosarioThis paper presents the first data on the identification, characterization and quantification of microcystins isolated from both an extract of a cyanobacteria natural bloom, collected from a eutrophic Moroccan reservoir (Lalla Takerkoust, Marrakesh) and an isolated strain cultivated under laboratory conditions. The isolation and purification of toxins was performed by reverse phase HPLC and then characterized by amino acid analysis and fast atom bombardment mass spectrometry (FAB-MS). Chemical characterization of the toxins from the bloom revealed variants of microcystins such as Mcyst-LR, Mcyst-RR, Mcyst-YR and [D-Asp3]Mcyst-LR. However, the Microcystis aeruginosa strain produced only Mcyst-RR. Using an ELISA assay the total microcystin contents of eight bloom samples collected from 1994 to 1997 ranged from 0.7 to 8.8 μg/mg of lyophilized material. The two isolated Microcystis strains contained higher amounts of microcystins (0.65 μg/ mg of dry weight) than the Pseudanabaena strains (0.021 μg/mg of dry weight). Our results show that the presence of cyanobacteria toxins in water used for drinking in a North African country may be regarded as an health hazard. These results are a contribution to the knowledge of the biogeography of toxic cyanobacteria and their toxins, namely in north African countries.
- Culture-dependent characterization of cyanobacterial diversity in the intertidal zones of the Portuguese coast: A polyphasic studyPublication . Brito, Ângela; Ramos, Vitor; Seabra, Rui; Santos, Arlete; Santos, Catarina; Lopo, Miguel; Ferreira, Sérgio; Martins, António; Mota, Rita; Frazão, Bárbara; Martins, Rosario; Vasconcelos, Vítor; Tamagnini, PaulaCyanobacteria are important primary producers, and many are able to fix atmospheric nitrogen playing a key role in the marine environment. However, not much is known about the diversity of cyanobacteria in Portuguese marine waters. This paper describes the diversity of 60 strains isolated from benthic habitats in 9 sites (intertidal zones) on the Portuguese South and West coasts. The strains were characterized by a morphological study (light and electron microscopy) and by a molecular characterization (partial 16S rRNA, nifH, nifK, mcyA, mcyE/ndaF, sxtI genes). The morphological analyses revealed 35 morphotypes (15 genera and 16 species) belonging to 4 cyanobacterial Orders/Subsections. The dominant groups among the isolates were the Oscillatoriales. There is a broad congruence between morphological and molecular assignments. The 16S rRNA gene sequences of 9 strains have less than 97% similarity compared to the sequences in the databases, revealing novel cyanobacterial diversity. Phylogenetic analysis, based on partial 16S rRNA gene sequences showed at least 12 clusters. One-third of the isolates are potential N2-fixers, as they exhibit heterocysts or the presence of nif genes was demonstrated by PCR. Additionally, no conventional freshwater toxins genes were detected by PCR screening.
- Cyanobacteria in cosmetics: a natural alternative for anti-aging ingredientsPublication . Morone, Janaína; Lopes, Graciliana; Oliveira, Beatriz; Vasconcelos, Vítor; Martins, RosarioBeing exposed to endogenous and exogenous stressors, and being the body’s external defense line, skin protection is of pivotal importance, in order to maintain morphological and physiologic integrity and health. Fostering by individual psychological comfort, esthetic performance, and young appearance, along with motivation for natural products with less side effects and sustainable production, consumer’s demands drive the cosmetic industry into the relentless pursuit for innovation. In this context, cyanobacteria enforce as a promising source of ingredients with cosmetic potential. With the ability to withstand adverse conditions for survival, the adaptation to extreme environments is reflected in the production of compounds with moisturizing, photoprotective, antioxidant, and whitening potential, all attributes required in cosmetics, namely in anti-aging products. In this chapter, we will focus on the interconnection between cyanobacteria and skin, by presenting the main applications of these organisms in skincare products.
- Neuroprotective effects of cyanobacterial extractsPublication . Rodrigues, Flávia; Grosso, Clara; Ferreira, Leonor; Vasconcelos, Vítor; Reis, Mariana; Martins, Rosário; Martins, RosarioNeurodegenerative diseases (ND), namely Alzheimer’s disease (AD) affects millions of people worldwide. Despite their high incidence there is still no effective medical therapy. Cyanobacteria have been in the frontline of the search for therapies for ND. Several in silico, in vitro, and in vivo studies have provided support for the neuroprotective potential of cyanobacterial natural products, particularly in AD. In this context, the aim of this work was to screen cyanobacterial strains from the Blue Biotechnology and Ecotoxicology Culture Collection (LEGE-CC) for its anti-AD potential. 10 cyanobacterial strains (LEGE CC 06072, 06131, 06155, 06361, 07168, 07175, 07189, 11394, 11439, 16525) were cultivated and their dry biomass was extracted and fractionated by reverse-phase HPLC resulting in 8 fractions per strain. Fractions were evaluated for their ability to inhibit enzymes associated with AD pathogenesis, such as acetylcholinesterase (AChE) and butyrylcholinesterase (BuChE), using Ellman’s colorimetric method. In addition, their cytotoxicity was assessed against three cell lines, two of them related to the nervous system. The neuroblastoma cell line SH-SY5Y, usually used as model for neurotoxicity studies and the human cerebral microvascular endothelial cell line hCMEC/D3, representative of the blood-brain barrier. The mouse fibroblast cell line 3T3-L1 was used as a representation of the conjunctive tissue. Cell viability was measured after 24 and 48 hours using the MTT assay. Results: The fractions did not shown cytotoxicity against the cell lines used. The preliminary results regarding enzyme inhibition were not promising, with less than 30% inhibition. Our preliminary suggest that further confirmation tests need to be performed on the AD related enzymes (AChE and BuChE), and the study should be extended to include other cyanobacterial strains.