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- Cyanobacteria for skin care and cosmeceutical formulationsPublication . Melo, Luísa; Morone, Janaína; Silva, Margarida; Ferraz, Ricardo; Martins, RosárioSkin acts as a barrier from external stimulus such as pollutants and ultraviolet radiation. Disturbs in the skin are involved in skin aging, which mostly results on a thinner epidermis, dryness, wrinkles, and loss of elasticity. Synthetic ingredients in cosmetics are known to be more toxic and to cause negative impact on the environment. In a society increasingly worried with human and environment health, natural skin care products gain special attention and boosted the search for natural sources. Due to the production of bioactive compounds, cyanobacteria emerged as an excellent source for cosmetic ingredients. Cyanobacteria strains of CIIMAR culture collection (LEGE-CC) have already proven to be interesting for cosmetic purposes [1,2]. In this project we aimed to evaluate the potential of four LEGE-CC cyanobacteria strains for skin care purposes. The cytotoxicity of acetonic and aqueous extracts was evaluated in keratinocytes (HaCAT), fibroblasts (3T3L1) and endothelial cells (hCMEC/D3) along with the total phenolic content and antioxidant properties. Cytotoxic assays revealed toxicity of acetonic extracts to keratinocytes in the higher concentrations tested. Aqueous extracts revealed low or non-cytotoxicity. Mainly in low concentrations of extracts, cellular proliferation was registered. Aqueous extracts from strain JM/RS021A and acetone extracts from strain JM/RS035B revealed higher values for total phenolic compounds. The acetone extracts of strain JM/RS021A showed the greatest scavenging activity values on the DPPH assay.
- Stalling the course of neurodegenerative diseases: could cyanobacteria constitute a new approach toward therapy?Publication . Ramos, Vitória; Reis, Mariana; Ferreira, Leonor; Silva, Ana Margarida; Ferraz, Ricardo; Vieira, Mónica; Vasconcelos, Vitor; Martins, RosárioNeurodegenerative diseases (NDs) are characterized by progressive and irreversible neuronal loss, accompanied by a range of pathological pathways, including aberrant protein aggregation, altered energy metabolism, excitotoxicity, inflammation, and oxidative stress. Some of the most common NDs include Alzheimer’s Disease (AD), Parkinson’s Disease (PD), Multiple Sclerosis (MS), Amyotrophic Lateral Sclerosis (ALS), and Huntington’s Disease (HD). There are currently no available cures; there are only therapeutic approaches that ameliorate the progression of symptoms, which makes the search for new drugs and therapeutic targets a constant battle. Cyanobacteria are ancient prokaryotic oxygenic phototrophs whose long evolutionary history has resulted in the production of a plethora of biomedically relevant compounds with anti-inflammatory, antioxidant, immunomodulatory, and neuroprotective properties, that can be valuable in this field. This review summarizes the major NDs and their pathophysiology, with a focus on the anti-neurodegenerative properties of cyanobacterial compounds and their main effects.
- Evaluation of the potential of marine cyanobacteria towards Alzheimer’s diseasePublication . Moreira, Ana Rita; Silva, Ana Margarida; Vieira, Mónica; Martins, RosárioAlzheimer’s disease (AD) is one of the most prevalent neurodegenerative diseases (NDs) and the major cause of dementia. Despite the constant efforts to achieve cure, no treatment is currently effective and new approaches are urgently needed. Marine biotechnology has been at the frontline for the bioprospection of natural sources to treat ND. Several marine compounds have already provided evidence for anti-AD drugs by acting in mechanisms such as the inhibition of acetylcholinesterase (AChE). Among marine organisms, cyanobacteria have been recognized as a major source of bioactive compounds and the potential towards AD has been highlighted, namely AChE inhibitors. This project is included in a screening program that aims to evaluate the potential of cyanobacteria from the Culture Collection of CIIMAR -LEGE-CC against AD. In this work, 80 fractions of marine cyanobacteria were screened for the potential to inhibit AChE since this is a proven enzyme target to ameliorate the loss of cholinergic signal and to induce cytotoxicity in the neuroblastoma cell line SHY5Y, in the normal fibroblasts cell line 3T3L1, and in the endothelial cells from central nervous system capillaries hCMEC/D3. Results considering the enzymatic assays and cytotoxic assays revealed that the fractions are not toxic or with low toxicity. The strains Phormidium sp; an unidentified filamentous Synechococcales and Nodosilinea nodulosa revealed moderate toxicity towards AChE.
- 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 of Hierridin B from a culturable Cyanobium sp. strain isolated from the Portuguese coastPublication . Leão, Pedro N.; Pereira, Alban R.; Costa, Margarida; Ramos, Vítor; Martins, Rosário; Gerwick, William H.; Vasconcelos, VitorCyanobacteria are a genetically diverse group of phototrophic prokaryotes. On a secondary metabolite perspective, however, filamentous and benthic forms have been the major sources of compounds isolated from these organisms. Nevertheless, unicellular free-living, planktonic cyanobacteria also contain enzymatic machinery for secondary metabolite biosynthesis.
- Cosmetic application of cyanobacteria extracts with a sustainable vision to skincare: role in the antioxidant and antiaging processPublication . Morone, Janaína; Lopes, Graciliana; Morais, João; Neves, Jorge; Vasconcelos, Vítor; Martins, RosárioNature-based and sustainably sourced cosmetics have been dominating the area of skincare products worldwide. Due to their antioxidant and antiaging properties, compounds from cyanobacteria, such as carotenoids and phycobiliproteins, may replace synthetic ingredients in cosmetic formulations and may be used in products such as sunscreens, skincare creams, and makeup. In this study, we evaluated the potential of acetonic and aqueous extracts from cyanobacteria strains of the genera Cyanobium and Leptothoe and from strains within Synechococcales and Oscillatori ales orders, for use in cosmetics. Extractions were sequentially performed with acetone and water. Extracts were firstly analyzed for their toxicity to keratinocytes, fibroblasts, and endothelial cells (HaCAT, 3T3L1 and hCMEC/D3, respectively). The non-cytotoxic extracts were characterized in terms of total proteins, carotenoids, chlorophyll, phenols, phycobiliproteins, and analyzed for their antioxidant potential against the superoxide anion radical (O2 •−), and for their ability to inhibit key enzymes associated with the skin aging process. Aqueous extracts were richer in total proteins and phycobiliproteins. The aqueous extracts of Synechococcales cyanobacterium LEGE 181157 and Synechococcales cyanobacterium LEGE 181150 showed the highest value for total proteins (760.81 and 695.25 µg BSA mL−1 dry extract, respectively) and the best values regarding O2 •− scavenging (IC50 = 63.24 and 112.18 µg mL−1 dry extract, respectively) with a significant negative correlation ob served (p < 0.01). Moreover, aqueous extracts of Synechococcales cyanobacterium LEGE 181150 and Synechococcales cyanobacterium LEGE 181157 inhibited hyaluronidase, (IC50 of 483.86 and 645.06 µg mL−1 dry extract, respectively), with a significant negative correlation with total proteins (p < 0.05), pointing out the contribution of these compounds to the biological activities observed. Acetonic extracts were richer in carotenoids and phenols. Zeaxanthin and β-carotene were pre dominant among all strains, being present in higher amount in Cyanobium sp. LEGE 07175 (53.08 µg mg−1 ) and Leptothoe sp. LEGE 181156 (47.89 µg mg−1 ), respectively. The same strains also showed the highest values for collagenase inhibition at 750 µg mL−1 dry extract (32.88 and 36.61%, respectively). Furthermore, Leptothoe sp. LEGE 181156 exhibited the lowest IC50 value for tyrosinase inhibition (465.92 µg mL−1 dry extract) and Synechococcales cyanobacterium LEGE 181157 presented the best values for elastase inhibition (IC50 of 380.50 and IC25 of 51.43 µg mL−1 dry extract). In general, cyanobacteria extracts demonstrated potential for being used for antiaging purposes, with aqueous extracts being more efficient at free radicals scavenging and acetonic ones at avoiding degradation of dermal matrix components.
- A natural oxadiazine isolated from cyanobacteria kills cancer cells in multicellular culture systems by impairing cellular respirationPublication . Sousa, Maria Lígia; Preto, Marco; Martins, Rosário; Vasconcelos, Vítor; Linder, Stig; Urbatzka, RalphCyanobacteria are versatile microorganisms that ubiquitously inhabit terrestrial and aquatic ecosystems. They adapt to external threats by mainly producing secondary metabolites. Therefore, cyanobacteria have been recognized as producer of natural products with potential biotechnological applications, such as bioplastics, antifouling, antibiotics, antiprotozoal or anticancer treatment.
- 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.
- Citotoxicity of marine cyanobacteria from the portuguese coast agains breast cancer cellsPublication . Costa, Margarida; Leão, Pedro; Ribeiro, Maria João; Costa-Rodrigues, João; Garcia, Mónica; Barros, Piedade; Fernandes, Helena; Vasconcelos, Vítor; Martins, RosárioThe marine environment possesses an unmeasured chemical and biological diversity, being considered an extraordinary resource for the discovery of new therapeutic drugs. Between others, marine cyanobacteria have emerged as a prominent source of bioactive secondary metabolites with a promising anticancer potential, as the described and intensively studied dolastatins.
- Phytochemical profile, antioxidant activity and cytotoxicity against keratinocytes, fibroblasts and endothelial cells of picoplanktonic marine cyanobacteriaPublication . Morone, Janaína; Lopes, Graciliana; Preto, Marco; Vasconcelos, Vítor; Martins, RosárioCombining the increase demand for natural products in skin care formulations, and the bioactive arsenal of cyanobacteria, we aimed with this study to evaluate the potential of a 70% ethanolic extract of picocyanobacteria strains of the genera Cyanobium and Synechocystis for skin care applications.