ESS - CIIMAR@E2S - Posters apresentados em eventos científicos
URI permanente para esta coleção:
Navegar
Entradas recentes
- Bioprospecting for cellulose-degrading microorganismsPublication . Almeida, Liliana; Alexandrino, Diogo; Oliveira, Rui S.; Carvalho, M. Fátima; Freitas, Marisa; Freitas, MarisaCellulose, a complex polysaccharide, is one of the main components of plant and algae biomass and therefore the most abundant polymer found in nature, serving as a significant carbon source in various ecosystems. Bioprospecting for cellulolytic microbes is a promising strategy for discovering potential biocatalysts for the hydrolysis of lignocellulosic materials, including residues. This work aims to assess the cellulolytic potential of microbial isolates (bacteria and fungi) sourced from diverse environments and to establish a synthetic microbial consortium capable to enhance the management of cellulosic waste. The experimental approach encompasses biodegradation assays coupled with optimized colorimetric methods, to estimate cellulose consumption (Congo Red assay) and the concomitant production of oligomeric/monomeric sugars (Dinitrosalicylic acid assay). For bacterial strains, these biodegradation assays involve batch incubations in minimal liquid medium supplied with cellulose as the sole carbon source, while solid medium is being used for fungi. Both assays are being run under mesophilic temperatures (28-30 ºC) and aerobic conditions. Upon achieving a final selection, strains exhibiting the best cellulose degradation performances will be assembled into a synthetic consortium that will be evaluated for their cellulose degradation capability. Future steps will also include phylogenetic identification of the cellulose degrading isolates through 16S and ITS rRNA gene sequence analysis. This study has the potential to identify novel cellulolytic microbes, highlighting the substantial role microorganisms play in ecosystem processes and their diverse applications in biotechnology.
- Determination of Vitamin C content in spinach plants grown under the use of cyanobacteria biomass as fertilizerPublication . Martins, Diogo; Massa, Anabella; Reimão, Mariana; Vasconcelos, Vítor; Campos, Alexandre; Pinto, Edgar; Freitas, Marisa; REIMÃO BORGES LOPES DA SILVA, MARIANA; Pinto, Edgar; Freitas, MarisaThe agricultural sector is continuously exploring sustainable and innovative approaches to enhance crop productivity, driving the quest for greener alternatives over synthetic fertilizers. Cyanobacteria have been reported as a promising agricultural fertilizer, with positive effects on crop yield. However, little is known about its potential effects on the produced vegetables' nutritional quality. Studies have documented that exposure of plants to cyanobacterial crude extracts stimulates the production of enzymatic and non-enzymatic antioxidants. Vitamin C, a non-enzymatic antioxidant, plays a crucial role in protecting cells from oxidative stress and spinach is known to be relatively high in vitamin C compared to other vegetables. The purpose of this study was to determine the content of vitamin C in spinach plants grown under the use of cyanobacterial biomass as fertilizer. Spinach plants were tested in soil, under six different conditions: (i) control, (ii) commercial chemical fertilizer, cyanobacterial biomass (iii) non-cyanotoxin producer, and cyanotoxin producer of (iv) Anatoxina (ANA), (v) Microcystin (MC), and (vi) Cylindrospermopsin (CYN). The analysis of vitamin C in spinach plants was performed according to EN 14130:2003. The results showed an increased content of vitamin C in all exposed groups when compared to the control (37 mg/Kg), with statistical differences in the conditions exposed to MC (56 mg/kg), ANA (76 mg/kg), and CYN (114 mg/kg). The results suggest that the rise in vitamin C may be related to a plant defence mechanism against oxidative stress potentially generated by exposure to cyanotoxins. Although the antioxidant content in spinach plants can be enhanced as a mechanism to cope with oxidative stress, prolonged exposure may increase plants' susceptibility to accumulate cyanotoxins, which may pose a risk to human health. Additional studies are needed to understand all the positive and negative effects of using cyanobacteria biomass as a biofertilizer.
- Evaluation of the anticancer potential of the macrofungus Pisolithus arhizus mycelium and culture mediumPublication . Santos, Germana; Preto, Marco; Vasconcelos, Vítor; Martins, Rosário; Oliveira, Rui S.; Martins, RosarioMacrofungi produce remarkable biomedical products that can make a significant contribution to health. Pisolithus arhizus is a fungal species of the phylum Basidiomycota. It is mainly found in association with the roots of some trees species, establishing a mutualistic relationship with them, facilitating the absorption of nutrients from the soil in exchange for carbohydrates produced by the host plant. As recently reviewed by us, this macrofungus has aroused great interest due to its promising therapeutic properties and bioactive effects. Crude extracts were prepared from the mycelium and culture medium of P.arhizus using a mixture of dichloromethane:methanol (2:1. The extracts were then separated into nine fractions using vacuum liquid chromatography. The fractions were tested for cytotoxicity against the RKO colon adenocarcinoma cell line and 3T3 fibroblasts cell line. Cell viability was assessed using the 3-(4,5-dimethyl-2-thiazolyl)-2,5-diphenyl-2H-tetrazolium bromide (MTT) reduction assay. Preliminary results revealed a dose dependent cytotoxicity against RKO cell line with no significant cytotoxicity to 3T3 cell lines, in fractions B and C. Those fractions corresponded to extraction with 70% Hex:30% EtOAc and 60% Hex:40% EtOAc, respectively. The results indicate that P.arhizus mycelium is a source of compounds with anticancer activity. However, more in-depth studies are needed to analyze the chemical compounds from the various parts of P. arhizus and investigate their biological and toxicological activities. Exploring the bioactive potential of P. arhizus is key to developing a complete understanding of its therapeutic benefits.
- 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.
- Cylindrospermopsin and glyphosate accumulation in lettuce (Lactuca sativa) simultaneously exposed to both toxicants in hydroponic and soil systemsPublication . Sengupta, S.; Freitas, Marisa; Pinto, Edgar; Ferreira, I.; Oliveira, F.; Azevedo, J.; Prieto, A.; Diez-Quijada, L.; Jos, A.; Cameán, A.M.; Campos, A.; Vasconcelos, V.In nature, the simultaneous occurrence of multiple emergent contaminants such as cyanotoxins (e.g., cylindrospermopsin (CYN)) and herbicides (e.g., glyphosate (GLY)), is highly expectable and it can be anticipated, mainly in the aquatic and terrestrial environments. The use of contaminated water for irrigation can be hazardous to the agricultural sector and some studies have reported that, individually, these contaminants can be accumulated in the edible tissues exerting a negative influence on crop plants safety and ultimately in human health. Furthermore, recent studies have suggested that some cyanotoxins (e.g., microcystins) can change the membrane permeability of roots, resulting in changes in the accumulation rates of other contaminants in plants. Since edible plants are exposed to a wide variety of substances through irrigation water, there is increasing concern in the potential adverse effects of the interactions between those substances when present simultaneously, especially when this can have potential public health consequences. The aim of this study was to determine the accumulation of CYN in Lactuca sativa simultaneously exposed to GLY at environmentally relevant concentrations. Lettuce plants were exposed for 15 days to 50 μg/L or kg of CYN-containing crude extract (Chrysosporum ovalisporum culture - LEGE X001) and 750 μg/L or kg of GLY, in hydroponic and soil systems, respectively. The resins (HP20, SP700, and XAD18) were evaluated for MC-LR uptake kinetics, capacities, and extraction efficiencies and simple procedures were developed for determining MC-LR concentration in binding disc extracts by Adda-ELISA (U.S. EPA Method 546). The XAD18-DGT/Adda-ELISA method had a 7-d deployment time detection limit of ≈0.05 μg/L and capacity of > 250 μg/L of MC-LR in water samples which encompass U.S. EPA and WHO advisory concentrations for drinking and recreational waters. The XAD18DGT/Adda-ELISA method determined timeaveraged MC-LR concentrations in waters with wide ranging pH (4.9–8.3) and ionic strength (0.04–0.8 M) under well-stirred and quiescent conditions with 90–101% accuracy. In addition to high sensitivity and accuracy, the method is simple, inexpensive, and applicable for determining MC-LR and related MCs concentrations in waterbodies with wide ranging chemical characteristics and hydrodynamic conditions. 4.11.07 Cylindrospermopsin and Glyphosate Accumulation in Lettuce (Lactuca sativa) Simultaneously Exposed to Both Toxicants in Hydroponic and Soil Systems S. Sengupta, School of Bio Sciences and Technology Vellore Institute of Technology, Vellore - 632 014, Tamil Nadu, India; M.M. Freitas, School of Health, Polytechnic Institute of Porto; E. Pinto, I. Ferreira, LAQV/REQUIMTE, Departament of Chemical Sciences, Faculty of Pharmacy, University of Porto, Rua Jorge de Viterbo Ferreira 228, 4050313 Porto, Portugal; F. Oliveira, J. Azevedo, CIIMAR - Interdisciplinary Centre of Marine and Environmental Research, University of Porto, Terminal de Cruzeiros do Porto de Leixões, Av. General Norton de Matos, s/n, 4450–208 Porto; A. Prieto, L. Diez-Quijada, A. Jos, A.M. Cameán, Area of Toxicology, Faculty of Pharmacy, Universidad de Sevilla, Profesor García González n◦2, 41012 Seville, Spain / Toxicology; A. Campos, Interdisciplinary Centre of Marine and Environmental Sciences, CIIMAR; V. Vasconcelos, CIIMAR - Interdisciplinary Centre of Marine and Environmental Research, University of Porto, Terminal de Cruzeiros do Porto de Leixões, Av. General Norton de Matos, s/n, 4450–208 Porto In nature, the simultaneous occurrence of multiple emergent contaminants such as cyanotoxins (e.g., cylindrospermopsin (CYN)) and herbicides (e.g., glyphosate (GLY)), is highly expectable and it can be anticipated, mainly in the aquatic and terrestrial environments. The use of contaminated water for irrigation can be hazardous to the agricultural sector and some studies have reported that, individually, these contaminants can be accumulated in the edible tissues exerting a negative influence on crop plants safety and ultimately in human health. Furthermore, recent studies have suggested that some cyanotoxins (e.g., microcystins) can change the membrane permeability of roots, resulting in changes in the accumulation rates of other contaminants in plants. Since edible plants are exposed to a wide variety of substances through irrigation water, there is increasing concern in the potential adverse effects of the interactions between those substances when present simultaneously, especially when this can have potential public health consequences. The aim of this study was to determine the concentration of CYN and GLY in lettuce plants (roots and leaves) was determined by LC/MSMS. The results show that, at the described conditions, CYN was accumulated in roots (0.06-7.62 μg CYN/g Dw) and leaves (0.13-1.1 μg CYN/g Dw) of lettuce, especially when plants were exposed in hydroponic system. However, interestingly, when lettuce plants were exposed simultaneously to both toxicants the concentration of CYN assimilated by lettuce plants (roots and leaves) was respectively, 1.5fold and 1-3-2.2-fold lower than in the exposure to isolated CYN. Conversely, the plants exposed to the mixture in soil system, showed that the concentration of GLY incorporated by lettuce (roots and leaves) was higher than in the exposure to the isolated compound (0.04 - 0.21 µg GLY/g and < LOQ - 0.84 µg GLY/g, respectively). This finding highlights the potential for the enhancement of GLY accumulation in lettuce plants due to their cooccurrence with CYN, and it underlines the importance of further research regarding the mechanism involved.
- Bioaccessibility and changes on cylindrospermopsin concentration in edible mussels over storage and processing time.Publication . Freitas, Marisa; Azevedo, Joana; Carvalho, António Paulo; Mendes, Vera; Manadas, Bruno; Campos, Alexandre; Vasconcelos, VítorThe cyanotoxin cylindrospermopsin has been recognized of increased concern due to the global expansion of its main producer, Cylindrospermopsis raciborskii. Previous studies have shown that aquatic organisms, especially bivalves, can accumulate high levels of cylindrospermopsin. Based on the potential for human health risks, a provisional tolerable daily intake of 0.03 µg/kg body-weight has been recommended. However, human exposure assessment has been based on the cylindrospermopsin concentration in raw food items. This study aimed to assess the changes on cylindrospermopsin concentration in edible mussels over storage and processing time as well as cylindrospermopsin bioaccessibility. Mussels, (Mytilus galloprovincialis) fed cylindrospermopsin-producing C. raciborskii, were subjected to the treatments and then analyzed by LC-MS/MS. Mussels stored frozen allowed a significantly higher recovery of cylindrospermopsin (52.5%/48 h and 57.7%/one week). The cooking treatments did not produce significant differences in cylindrospermopsin concentration in mussel matrices (flesh), however, cylindrospermopsin was found in the cooking water, suggesting that heat processing can be used to reduce the availability of cylindrospermopsin in this food item. The in vitro digestion with salivary and gastrointestinal juices considerably decreased the cylindrospermopsin availability in uncooked and steamed mussels, highlighting the importance in integrating the bioaccessibility in the human health risk assessment.
- Tropomyosin variations in the mussel Mytilus galloprovincialis exposed to diarrhetic shellfish toxinsPublication . Rodrigues, Miguel; Domínguez-Pérez, Dany; Azevedo, Catarina; Costa, Pedro; Martins, José Carlos; Antunes, Jorge; Vasconcelos, Vítor; Campos, Alexandre; Freitas, MarisaThe consumption of seafood contaminated with diarrhetic shellfish toxins (DSTs) represents a food safety threat, being shellfish the main vector for human consumers. Moreover, DSTs can produce significant alterations at the protein level in shellfish and this can affect the content of allergens.
- Monitoring of physico-chemical parameters and their influence on the cyanobacteria occurrence: a case study in Alqueva reservoirs.Publication . Silva, Inês; Barreiro, Aldo; Vasconcelos, Vitor; Campos, Alexandre; Freitas, MarisaAlqueva complex is constituted by 17 reservoirs/dams interconnected by waterways, being built to provide water for agricultural irrigation, as well as for human consumption and recreational activities in Alentejo region.
- Anticancer potential of spores of the soil fungus Pisolithus tinctoriusPublication . Oliveira, Rui S.; Alves, Ricardo; Preto, Marco; Martins, RosárioCancer is one of the major causes of death worldwide being the search for new anticancer drugs essential for the treatment of this disease. The sporocarps of the soil fungus Pisolithus tinctorius contain pisosterol, a triterpene that has been shown to have antitumor activity against some cancer cell lines. Nevertheless, no studies have focused on the anticancer potential of other structures such as spores, and so the anticancer potential of P. tinctorius, remains largely unknown. The main objective of this study was to evaluate the potential of P. tinctorius spores as a source of anticancer compounds.
- 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.
- «
- 1 (current)
- 2
- 3
- »