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Cyanobacteria are a group of photosynthetic prokaryotes that pose a great concern in the aquatic environments related to contamination and poisoning of wild life and humans. Some species of cyanobacteria produce potent toxins such as microcystins (MCs), which are extremely aggressive to several organisms, including animals and humans. In order to protect human health and prevent human exposure to this type of organisms and toxins, regulatory limits for MCs in drinking water have been established in most countries. In this regard, the World Health Organization (WHO) proposed 1 µg MCs/L as the highest acceptable concentration in drinking water. However, regulatory limits were not defined in waters used in other applications/activities, constituting a potential threat to the environment and to human health. Indeed, water contaminated with MCs or other cyanotoxins is recurrently used in agriculture and for crop and food production. Several deleterious effects of MCs including a decrease in growth, tissue necrosis, inhibition of photosynthesis and metabolic changes have been reported in plants leading to the impairment of crop productivity and economic loss. Studies have also revealed significant accumulation of MCs in edible tissues and plant organs, which raise concerns related to food safety. This work aims to systematize and analyze the information generated by previous scientific studies, namely on the phytotoxicity and the impact of MCs especially on growth, photosynthesis and productivity of agricultural plants. Morphological and physiological parameters of agronomic interest are overviewed in detail in this work, with the aim to evaluate the putative impact of MCs under field conditions. Finally, concentration-dependent effects are highlighted, as these can assist in future guidelines for irrigation waters and establish regulatory limits for MCs.
Alexandre Campos; El Redouane; Marisa Freitas; Samuel Amaral; Tomé Azevedo; Leticia Loss; Csaba Máthé; Zakaria Mohamed; Brahim Oudra; Vitor Vasconcelos. Impacts of Microcystins on Morphological and Physiological Parameters of Agricultural Plants: A Review. Plants 2021, 10, 639 .
AMA StyleAlexandre Campos, El Redouane, Marisa Freitas, Samuel Amaral, Tomé Azevedo, Leticia Loss, Csaba Máthé, Zakaria Mohamed, Brahim Oudra, Vitor Vasconcelos. Impacts of Microcystins on Morphological and Physiological Parameters of Agricultural Plants: A Review. Plants. 2021; 10 (4):639.
Chicago/Turabian StyleAlexandre Campos; El Redouane; Marisa Freitas; Samuel Amaral; Tomé Azevedo; Leticia Loss; Csaba Máthé; Zakaria Mohamed; Brahim Oudra; Vitor Vasconcelos. 2021. "Impacts of Microcystins on Morphological and Physiological Parameters of Agricultural Plants: A Review." Plants 10, no. 4: 639.
Diarrhetic shellfish toxins (DSTs) are among the most prevalent marine toxins in Europe’s and in other temperate coastal regions. These toxins are produced by several dinoflagellate species; however, the contamination of the marine trophic chain is often attributed to species of the genus Dinophysis. This group of toxins, constituted by okadaic acid (OA) and analogous molecules (dinophysistoxins, DTXs), are highly harmful to humans, causing severe poisoning symptoms caused by the ingestion of contaminated seafood. Knowledge on the mode of action and toxicology of OA and the chemical characterization and accumulation of DSTs in seafood species (bivalves, gastropods and crustaceans) has significantly contributed to understand the impacts of these toxins in humans. Considerable information is however missing, particularly at the molecular and metabolic levels involving toxin uptake, distribution, compartmentalization and biotransformation and the interaction of DSTs with aquatic organisms. Recent contributions to the knowledge of DSTs arise from transcriptomics and proteomics research. Indeed, OMICs constitute a research field dedicated to the systematic analysis on the organisms’ metabolisms. The methodologies used in OMICs are also highly effective to identify critical metabolic pathways affecting the physiology of the organisms. In this review, we analyze the main contributions provided so far by OMICs to DSTs research and discuss the prospects of OMICs with regard to the DSTs toxicology and the significance of these toxins to public health, food safety and aquaculture.
Alexandre Campos; Marisa Freitas; André De Almeida; José Martins; Dany Domínguez-Pérez; Hugo Osório; Vitor Vasconcelos; Pedro Reis Costa. OMICs Approaches in Diarrhetic Shellfish Toxins Research. Toxins 2020, 12, 493 .
AMA StyleAlexandre Campos, Marisa Freitas, André De Almeida, José Martins, Dany Domínguez-Pérez, Hugo Osório, Vitor Vasconcelos, Pedro Reis Costa. OMICs Approaches in Diarrhetic Shellfish Toxins Research. Toxins. 2020; 12 (8):493.
Chicago/Turabian StyleAlexandre Campos; Marisa Freitas; André De Almeida; José Martins; Dany Domínguez-Pérez; Hugo Osório; Vitor Vasconcelos; Pedro Reis Costa. 2020. "OMICs Approaches in Diarrhetic Shellfish Toxins Research." Toxins 12, no. 8: 493.
Cyanobacteria and cyanotoxins constitute a serious environmental and human health problem. Moreover, concerns are raised with the use of contaminated water in agriculture and vegetable production as this can lead to food contamination and human exposure to toxins as well as impairment in crop development and productivity. The objective of this work was to assess the susceptibility of two green vegetables, spinach and lettuce, to the cyanotoxins microcystin (MC) and cylindrospermopsin (CYN), individually and in mixture. The study consisted of growing both vegetables in hydroponics, under controlled conditions, for 21 days in nutrient medium doped with MC or CYN at 10 μg/L and 50 μg/L, or CYN/MC mixture at 5 + 5 μg/L and 25 + 25 μg/L. Extracts from M. aeruginosa and C. ovalisporum were used as sources of toxins. The study revealed growth inhibition of the aerial part (Leaves) in both species when treated with 50µg/L of MC, CYN and CYN/MC mixture. MC showed to be more harmful to plant growth than CYN. Moreover spinach leaves growth was inhibited by both 5 + 5 and 25 + 25 µg/L CYN/MC mixtures, whereas lettuce leaves growth was inhibited only by 25 + 25 µg/L CYN/MC mixture. Overall, growth data evidence increased sensitivity of spinach to cyanotoxins in comparison to lettuce. On the other hand, plants exposed to CYN/MC mixture showed differential accumulation of CYN and MC. In addition, CYN, but not MC, was translocated from the roots to the leaves. CYN and MC affected the levels of minerals particularly in plant roots. The elements most affected were Ca, K and Mg. However, in leaves K was the mineral that was affected by exposure to cyanotoxins.
Maria Llana-Ruiz-Cabello; Angeles Jos; Ana Cameán; Flavio Oliveira; Aldo Barreiro; Joana Machado; Joana Azevedo; Edgar Pinto; Agostinho Almeida; Alexandre Campos; Vitor Vasconcelos; Marisa Freitas. Analysis of the Use of Cylindrospermopsin and/or Microcystin-Contaminated Water in the Growth, Mineral Content, and Contamination of Spinacia oleracea and Lactuca sativa. Toxins 2019, 11, 624 .
AMA StyleMaria Llana-Ruiz-Cabello, Angeles Jos, Ana Cameán, Flavio Oliveira, Aldo Barreiro, Joana Machado, Joana Azevedo, Edgar Pinto, Agostinho Almeida, Alexandre Campos, Vitor Vasconcelos, Marisa Freitas. Analysis of the Use of Cylindrospermopsin and/or Microcystin-Contaminated Water in the Growth, Mineral Content, and Contamination of Spinacia oleracea and Lactuca sativa. Toxins. 2019; 11 (11):624.
Chicago/Turabian StyleMaria Llana-Ruiz-Cabello; Angeles Jos; Ana Cameán; Flavio Oliveira; Aldo Barreiro; Joana Machado; Joana Azevedo; Edgar Pinto; Agostinho Almeida; Alexandre Campos; Vitor Vasconcelos; Marisa Freitas. 2019. "Analysis of the Use of Cylindrospermopsin and/or Microcystin-Contaminated Water in the Growth, Mineral Content, and Contamination of Spinacia oleracea and Lactuca sativa." Toxins 11, no. 11: 624.
Toxic cyanobacterial blooms are recognized as an emerging environmental threat worldwide. Although microcystin-LR is the most frequently documented cyanotoxin, studies on cylindrospermopsin have been increasing due to the invasive nature of cylindrospermopsin-producing cyanobacteria. The number of studies regarding the effects of cyanotoxins on agricultural plants has increased in recent years, and it has been suggested that the presence of microcystin-LR and cylindrospermopsin in irrigation water may cause toxic effects in edible plants. The uptake of these cyanotoxins by agricultural plants has been shown to induce morphological and physiological changes that lead to a potential loss of productivity. There is also evidence that edible terrestrial plants can bioaccumulate cyanotoxins in their tissues in a concentration dependent-manner. Moreover, the number of consecutive cycles of watering and planting in addition to the potential persistence of microcystin-LR and cylindrospermopsin in the environment are likely to result in groundwater contamination. The use of cyanotoxin-contaminated water for agricultural purposes may therefore represent a threat to both food security and food safety. However, the deleterious effects of cyanotoxins on agricultural plants and public health seem to be dependent on the concentrations studied, which in most cases are non-environmentally relevant. Interestingly, at ecologically relevant concentrations, the productivity and nutritional quality of some agricultural plants seem not to be impaired and may even be enhanced. However, studies assessing if the potential tolerance of agricultural plants to these concentrations can result in cyanotoxin and allergen accumulation in the edible tissues are lacking. This review combines the most current information available regarding this topic with a realistic assessment of the impact of cyanobacterial toxins on agricultural plants, groundwater quality and public health.info:eu-repo/semantics/publishedVersio
Joana Filipa Félix Machado; Alexandre Campos; Vitor Vasconcelos; Marisa Freitas. Effects of microcystin-LR and cylindrospermopsin on plant-soil systems: A review of their relevance for agricultural plant quality and public health. Environmental Research 2017, 153, 191 -204.
AMA StyleJoana Filipa Félix Machado, Alexandre Campos, Vitor Vasconcelos, Marisa Freitas. Effects of microcystin-LR and cylindrospermopsin on plant-soil systems: A review of their relevance for agricultural plant quality and public health. Environmental Research. 2017; 153 ():191-204.
Chicago/Turabian StyleJoana Filipa Félix Machado; Alexandre Campos; Vitor Vasconcelos; Marisa Freitas. 2017. "Effects of microcystin-LR and cylindrospermopsin on plant-soil systems: A review of their relevance for agricultural plant quality and public health." Environmental Research 153, no. : 191-204.
Natural toxins produced by freshwater cyanobacteria, such as cylindrospermopsin, have been regarded as an emergent environmental threat. Despite the risks for food safety, the impact of these water contaminants in agriculture is not yet fully understood. Carrots (Daucus carota) are root vegetables, extensively consumed worldwide with great importance for human nourishment and economy. It is, therefore, important to evaluate the possible effects of using water contaminated with cyanotoxins on carrot cultivation. The aim of this work was to investigate cylindrospermopsin effects on D. carota grown in soil and irrigated for 30 days, with a Chrysosporum ovalisporum extract containing environmentally relevant concentrations of cylindrospermopsin (10 and 50 μg/L). The parameters evaluated were plant growth, photosynthetic capacity, and nutritional value (mineral content) in roots of carrots, as these are the edible parts of this plant crop. The results show that, exposure to cylindrospermopsin did not have a clear negative effect on growth or photosynthesis of D. carota, even leading to an increase of both parameters. However, alterations in mineral contents were detected after exposure to crude extracts of C. ovalisporum containing cylindrospermopsin. A general decline was observed for most minerals (Ca, Mg, Na, Fe, Mn, Zn, Mo, and P), although an increase was shown in the case of K and Cu, pointing to a possible interference of the cyanobacterial extract in mineral uptake. This study is the first to evaluate the effects of C. ovalisporum extracts on a root vegetable, however, more research is necessary to understand the effects of this toxin in environmentally relevant scenarios.
Remedios Guzmán-Guillén; Alexandre Campos; Joana Filipa Félix Machado; Marisa Freitas; Joana Azevedo; Edgar Pinto; Agostinho Almeida; Ana M. Cameán; Vitor Vasconcelos. Effects of Chrysosporum (Aphanizomenon) ovalisporum extracts containing cylindrospermopsin on growth, photosynthetic capacity, and mineral content of carrots (Daucus carota). Ecotoxicology 2016, 26, 22 -31.
AMA StyleRemedios Guzmán-Guillén, Alexandre Campos, Joana Filipa Félix Machado, Marisa Freitas, Joana Azevedo, Edgar Pinto, Agostinho Almeida, Ana M. Cameán, Vitor Vasconcelos. Effects of Chrysosporum (Aphanizomenon) ovalisporum extracts containing cylindrospermopsin on growth, photosynthetic capacity, and mineral content of carrots (Daucus carota). Ecotoxicology. 2016; 26 (1):22-31.
Chicago/Turabian StyleRemedios Guzmán-Guillén; Alexandre Campos; Joana Filipa Félix Machado; Marisa Freitas; Joana Azevedo; Edgar Pinto; Agostinho Almeida; Ana M. Cameán; Vitor Vasconcelos. 2016. "Effects of Chrysosporum (Aphanizomenon) ovalisporum extracts containing cylindrospermopsin on growth, photosynthetic capacity, and mineral content of carrots (Daucus carota)." Ecotoxicology 26, no. 1: 22-31.
Toxic cyanobacterial blooms are often observed in freshwaters and may reflect the increased eutrophication of these environments and alterations in climate. Cyanotoxins, such as microcystins (MCs), are an effective threat to many life forms, ranging from plants to humans. Despite the research conducted to date on cyanotoxins, the risks associated to the use of contaminated water in agriculture require further elucidation. To tackle this aim, a research was conducted with the root-vegetable Daucus carota. The specific aims of this work were the following: (i) to evaluate the effects of MC-LR on the plant growth and photosynthesis; (ii) to evaluate the nutritional quality of carrot roots; and (iii) to measure bioaccumulation. To this purpose, young carrots were grown in soil during 1 month in natural conditions and exposed to Mycrocystis aeruginosa aqueous extracts containing environmentally realistic concentrations of MC-LR (10 and 50 MC-LR μg/L). The results showed that MC-LR may decrease root growth after 28 days of exposure to 50 μg/L and increase photosynthetic efficiency. We also observed changes in mineral and vitamin content in carrots as a result of the exposure to contaminated water. Moreover, MC-LR was detected in carrot roots by ELISA at very low concentration 5.23 ± 0.47 ng MC eq./g FW. The soil retained 52.7 % of the toxin potentially available for plants. This result could be attributed to MC-LR adsorption by soil particles or due to microbial degradation of the toxin. We conclude that the prolonged use of MC-LR-contaminated water may affect crop growth, alter the nutritional value of vegetable products, and potentiate contamination.
J. Machado; J. Azevedo; M. Freitas; E. Pinto; A. Almeida; V. Vasconcelos; A. Campos. Analysis of the use of microcystin-contaminated water in the growth and nutritional quality of the root-vegetable, Daucus carota. Environmental Science and Pollution Research 2016, 24, 752 -764.
AMA StyleJ. Machado, J. Azevedo, M. Freitas, E. Pinto, A. Almeida, V. Vasconcelos, A. Campos. Analysis of the use of microcystin-contaminated water in the growth and nutritional quality of the root-vegetable, Daucus carota. Environmental Science and Pollution Research. 2016; 24 (1):752-764.
Chicago/Turabian StyleJ. Machado; J. Azevedo; M. Freitas; E. Pinto; A. Almeida; V. Vasconcelos; A. Campos. 2016. "Analysis of the use of microcystin-contaminated water in the growth and nutritional quality of the root-vegetable, Daucus carota." Environmental Science and Pollution Research 24, no. 1: 752-764.
Aquaculture is one of the fastest growing world industries due to the increased demand of fishery products for human consumption and capture restrictions as a result of aquatic ecosystems exploitation. Aquaculture is therefore an extremely competitive business with major challenges to keep a high quality farmed fish through a sustainable production system. These challenges imposed quite important changes in this more traditional market, namely at the level of integrating scientific knowledge and research. Proteomics presents itself as a powerful tool not only for a better understanding of the marine organisms biology but also to provide solutions to deal with changes and the increasing demand in the system’s production line to ensure the required supply. In this book chapter we will give an overview of aquaculture nowadays, its challenges and describe relevant proteomics studies in several areas of this industry. A brief description of the proteomics technical approaches applied to aquaculture will also be addressed.
Pedro M. Rodrigues; Denise Schrama; Alexandre Campos; Hugo Osório; Marisa Freitas. Applications of Proteomics in Aquaculture. Agricultural Proteomics Volume 1 2016, 175 -209.
AMA StylePedro M. Rodrigues, Denise Schrama, Alexandre Campos, Hugo Osório, Marisa Freitas. Applications of Proteomics in Aquaculture. Agricultural Proteomics Volume 1. 2016; ():175-209.
Chicago/Turabian StylePedro M. Rodrigues; Denise Schrama; Alexandre Campos; Hugo Osório; Marisa Freitas. 2016. "Applications of Proteomics in Aquaculture." Agricultural Proteomics Volume 1 , no. : 175-209.
The alkaloid cylindrospermopsin has been recognized of increased concern due to the global expansion of its main producer, Cylindrospermopsis raciborskii. Previous studies have shown that 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, the human exposure assessment has been based on the cylindrospermopsin concentration in raw food items. Thus, this study aimed to assess the changes on cylindrospermopsin concentration in edible mussels with 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% in 48 h and 57.7% in one week). The cooking treatments did not produce significant differences in cylindrospermopsin concentration in the mussel matrices (flesh), however, cylindrospermopsin was found in the cooking water, suggesting that heat processing can be used to reduce the availability of cylindrospermopsin. The in vitro digestion considerably decreased the cylindrospermopsin availability in uncooked and steamed mussels, highlighting the importance in integrating the bioaccessibility of cylindrospermopsinin in the human health risk assessment.info:eu-repo/semantics/publishedVersio
Marisa Freitas; Joana Azevedo; António Paulo Carvalho; Vera M. Mendes; Bruno Manadas; Alexandre Campos; Vitor Vasconcelos. Bioaccessibility and changes on cylindrospermopsin concentration in edible mussels with storage and processing time. Food Control 2016, 59, 567 -574.
AMA StyleMarisa Freitas, Joana Azevedo, António Paulo Carvalho, Vera M. Mendes, Bruno Manadas, Alexandre Campos, Vitor Vasconcelos. Bioaccessibility and changes on cylindrospermopsin concentration in edible mussels with storage and processing time. Food Control. 2016; 59 ():567-574.
Chicago/Turabian StyleMarisa Freitas; Joana Azevedo; António Paulo Carvalho; Vera M. Mendes; Bruno Manadas; Alexandre Campos; Vitor Vasconcelos. 2016. "Bioaccessibility and changes on cylindrospermopsin concentration in edible mussels with storage and processing time." Food Control 59, no. : 567-574.
Toxic cyanobacterial blooms are documented worldwide as an emerging environmental concern. Recent studies support the hypothesis that microcystin-LR (MC-LR) and cylindrospermopsin (CYN) produce toxic effects in crop plants. Lettuce (Lactuca sativa L.) is an important commercial leafy vegetable that supplies essential elements for human nutrition; thus, the study of its sensitivity to MC-LR, CYN and a MC-LR/CYN mixture is of major relevance. This study aimed to assess the effects of environmentally relevant concentrations (1, 10 and 100 µg/L) of MC-LR, CYN and a MC-LR/CYN mixture on growth, antioxidant defense system and mineral content in lettuce plants. In almost all treatments, an increase in root fresh weight was obtained; however, the fresh weight of leaves was significantly decreased in plants exposed to 100 µg/L concentrations of each toxin and the toxin mixture. Overall, GST activity was significantly increased in roots, contrary to GPx activity, which decreased in roots and leaves. The mineral content in lettuce leaves changed due to its exposure to cyanotoxins; in general, the mineral content decreased with MC-LR and increased with CYN, and apparently these effects are time and concentration-dependent. The effects of the MC-LR/CYN mixture were almost always similar to the single cyanotoxins, although MC-LR seems to be more toxic than CYN. Our results suggest that lettuce plants in non-early stages of development are able to cope with lower concentrations of MC-LR, CYN and the MC-LR/CYN mixture; however, higher concentrations (100 µg/L) can affect both lettuce yield and nutritional quality.
Marisa Freitas; Joana Azevedo; Edgar Pinto; Joana Neves; Alexandre Campos; Vitor Vasconcelos. Effects of microcystin-LR, cylindrospermopsin and a microcystin-LR/cylindrospermopsin mixture on growth, oxidative stress and mineral content in lettuce plants (Lactuca sativa L.). Ecotoxicology and Environmental Safety 2015, 116, 59 -67.
AMA StyleMarisa Freitas, Joana Azevedo, Edgar Pinto, Joana Neves, Alexandre Campos, Vitor Vasconcelos. Effects of microcystin-LR, cylindrospermopsin and a microcystin-LR/cylindrospermopsin mixture on growth, oxidative stress and mineral content in lettuce plants (Lactuca sativa L.). Ecotoxicology and Environmental Safety. 2015; 116 ():59-67.
Chicago/Turabian StyleMarisa Freitas; Joana Azevedo; Edgar Pinto; Joana Neves; Alexandre Campos; Vitor Vasconcelos. 2015. "Effects of microcystin-LR, cylindrospermopsin and a microcystin-LR/cylindrospermopsin mixture on growth, oxidative stress and mineral content in lettuce plants (Lactuca sativa L.)." Ecotoxicology and Environmental Safety 116, no. : 59-67.
The intensification of agricultural productivity is an important challenge worldwide. However, environmental stressors can provide challenges to this intensification. The progressive occurrence of the cyanotoxins cylindrospermopsin (CYN) and microcystin-LR (MC-LR) as a potential consequence of eutrophication and climate change is of increasing concern in the agricultural sector because it has been reported that these cyanotoxins exert harmful effects in crop plants. A proteomic-based approach has been shown to be a suitable tool for the detection and identification of the primary responses of organisms exposed to cyanotoxins. The aim of this study was to compare the leaf-proteome profiles of lettuce plants exposed to environmentally relevant concentrations of CYN and a MC-LR/CYN mixture. Lettuce plants were exposed to 1, 10, and 100 lg/l CYN and a MC-LR/CYN mixture for five days. The proteins of lettuce leaves were separated by twodimensional electrophoresis (2-DE), and those that were differentially abundant were then identified by matrix-assisted laser desorption/ionization time of flight-mass spectrometry (MALDI-TOF/TOF MS). The biological functions of the proteins that were most represented in both experiments were photosynthesis and carbon metabolism and stress/defense response. Proteins involved in protein synthesis and signal transduction were also highly observed in the MC-LR/CYN experiment. Although distinct protein abundance patterns were observed in both experiments, the effects appear to be concentration-dependent, and the effects of the mixture were clearly stronger than those of CYN alone. The obtained results highlight the putative tolerance of lettuce to CYN at concentrations up to 100 lg/l. Furthermore, the combination of CYN with MC-LR at low concentrations (1 lg/l) stimulated a significant increase in the fresh weight (fr. wt) of lettuce leaves and at the proteomic level resulted in the increase in abundance of a high number of proteins. In contrast, many proteins exhibited a decrease in abundance or were absent in the gels of the simultaneous exposure to 10 and 100 lg/l MC-LR/CYN. In the latter, also a significant decrease in the fr. wt of lettuce leaves was obtained. These findings provide important insights into the molecular mechanisms of the lettuce response to CYN and MC-LR/CYN and may contribute to the identification of potential protein markers of exposure and proteins that may confer tolerance to CYN and MC-LR/CYN. Furthermore, because lettuce is an important crop worldwide, this study may improve our understanding of the potential impact of these cyanotoxins on its quality traits (e.g., presence of allergenic proteins)
Marisa Freitas; Alexandre Campos; Joana Azevedo; Aldo Barreiro; Sébastien Planchon; Jenny Renaut; Vitor Vasconcelos. Lettuce (Lactuca sativa L.) leaf-proteome profiles after exposure to cylindrospermopsin and a microcystin-LR/cylindrospermopsin mixture: A concentration-dependent response. Phytochemistry 2014, 110, 91 -103.
AMA StyleMarisa Freitas, Alexandre Campos, Joana Azevedo, Aldo Barreiro, Sébastien Planchon, Jenny Renaut, Vitor Vasconcelos. Lettuce (Lactuca sativa L.) leaf-proteome profiles after exposure to cylindrospermopsin and a microcystin-LR/cylindrospermopsin mixture: A concentration-dependent response. Phytochemistry. 2014; 110 ():91-103.
Chicago/Turabian StyleMarisa Freitas; Alexandre Campos; Joana Azevedo; Aldo Barreiro; Sébastien Planchon; Jenny Renaut; Vitor Vasconcelos. 2014. "Lettuce (Lactuca sativa L.) leaf-proteome profiles after exposure to cylindrospermopsin and a microcystin-LR/cylindrospermopsin mixture: A concentration-dependent response." Phytochemistry 110, no. : 91-103.
Natural toxins such as those produced by freshwater cyanobacteria have been regarded as an emergent environmental threat. However, the impact of these water contaminants in agriculture is not yet fully understood. The aim of this work was to investigate microcystin-LR (MC-LR) toxicity in Lycopersicon esculentum and the toxin accumulation in this horticultural crop. Adult plants (2 month-old) grown in a greenhouse environment were exposed for 2 weeks to either pure MC-LR (100 μg/L) or Microcystis aeruginosa crude extracts containing 100 μg/L MC-LR. Chlorophyll fluorescence was measured, leaf proteome investigated with two-dimensional gel electrophoresis and Matrix Assisted Laser Desorption Ionization Time-of-Flight (MALDI-TOF)/TOF, and toxin bioaccumulation assessed by liquid chromatography-mass spectrometry (LC-MS)/MS. Variations in several protein markers (ATP synthase subunits, Cytochrome b6-f complex iron-sulfur, oxygen-evolving enhancer proteins) highlight the decrease of the capacity of plants to synthesize ATP and to perform photosynthesis, whereas variations in other proteins (ribulose-1,5-bisphosphate carboxylase/oxygenase large subunit and ribose-5-phosphate isomerase) suggest an increase of carbon fixation and decrease of carbohydrate metabolism reactions in plants exposed to pure MC-LR and cyanobacterial extracts, respectively. MC-LR was found in roots (1635.21 μg/kg fw), green tomatoes (5.15–5.41 μg/kg fw), mature tomatoes (10.52–10.83 μg/kg fw), and leaves (12,298.18 μg/kg fw). The results raise concerns relative to food safety and point to the necessity of monitoring the bioaccumulation of water toxins in agricultural systems affected by cyanotoxin contamination.
Daniel Gutiérrez-Praena; Alexandre Campos; Joana Azevedo; Joana Neves; Marisa Freitas; Remédios Guzmán-Guillén; Ana María Cameán; Jenny Renaut; Vitor Vasconcelos. Exposure of Lycopersicon Esculentum to Microcystin-LR: Effects in the Leaf Proteome and Toxin Translocation from Water to Leaves and Fruits. Toxins 2014, 6, 1837 -1854.
AMA StyleDaniel Gutiérrez-Praena, Alexandre Campos, Joana Azevedo, Joana Neves, Marisa Freitas, Remédios Guzmán-Guillén, Ana María Cameán, Jenny Renaut, Vitor Vasconcelos. Exposure of Lycopersicon Esculentum to Microcystin-LR: Effects in the Leaf Proteome and Toxin Translocation from Water to Leaves and Fruits. Toxins. 2014; 6 (6):1837-1854.
Chicago/Turabian StyleDaniel Gutiérrez-Praena; Alexandre Campos; Joana Azevedo; Joana Neves; Marisa Freitas; Remédios Guzmán-Guillén; Ana María Cameán; Jenny Renaut; Vitor Vasconcelos. 2014. "Exposure of Lycopersicon Esculentum to Microcystin-LR: Effects in the Leaf Proteome and Toxin Translocation from Water to Leaves and Fruits." Toxins 6, no. 6: 1837-1854.
Accumulation of microcystin-LR (MC-LR) in edible aquatic organisms, particularly in bivalves, is widely documented. In this study, the effects of food storage and processing conditions on the free MC-LR concentration in clams (Corbicula fluminea) fed MC-LR-producing Microcystisaeruginosa (1 × 105 cell/mL) for four days, and the bioaccessibility of MC-LR after in vitro proteolytic digestion were investigated. The concentration of free MC-LR in clams decreased sequentially over the time with unrefrigerated and refrigerated storage and increased with freezing storage. Overall, cooking for short periods of time resulted in a significantly higher concentration (P < 0.05) of free MC-LR in clams, specifically microwave (MW) radiation treatment for 0.5 (57.5%) and 1 min (59%) and boiling treatment for 5 (163.4%) and 15 min (213.4%). The bioaccessibility of MC-LR after proteolytic digestion was reduced to 83%, potentially because of MC-LR degradation by pancreatic enzymes. Our results suggest that risk assessment based on direct comparison between MC-LR concentrations determined in raw food products and the tolerable daily intake (TDI) value set for the MC-LR might not be representative of true human exposure
Marisa Freitas; Joana Azevedo; António Paulo Carvalho; Alexandre Campos; Vitor Vasconcelos. Effects of storage, processing and proteolytic digestion on microcystin-LR concentration in edible clams. Food and Chemical Toxicology 2014, 66, 217 -223.
AMA StyleMarisa Freitas, Joana Azevedo, António Paulo Carvalho, Alexandre Campos, Vitor Vasconcelos. Effects of storage, processing and proteolytic digestion on microcystin-LR concentration in edible clams. Food and Chemical Toxicology. 2014; 66 ():217-223.
Chicago/Turabian StyleMarisa Freitas; Joana Azevedo; António Paulo Carvalho; Alexandre Campos; Vitor Vasconcelos. 2014. "Effects of storage, processing and proteolytic digestion on microcystin-LR concentration in edible clams." Food and Chemical Toxicology 66, no. : 217-223.
For musicians, the impact of noise exposure is not yet fully characterized. Some inconsistencies can be found in the methodology used to evaluate noise exposure. This study aims to analyze the noise exposure of musicians in a symphonic orchestra to understand their risk for hearing loss, applying the methodology proposed by ISO 9612:2009. Noise levels were monitored among musicians during the rehearsal of eight different repertoires. Test subjects were selected according to their instrument and position in the orchestra. Participants wore noise dosimeters throughout the rehearsals. A sound meter was used to analyze the exposure of the conductor. The results showed that musicians are exposed to high noise levels that can damage hearing. Brass, woodwind and percussion and timpani musicians were exposed to noise levels in excess of the upper exposure action level of 85 dB (A), while the other instrumental groups had a lower exposure action level of 80 dB (A). Percussion musicians were exposed to high peak noise levels of 135 dB (C). Sound levels varied by instrument, repertoire and position. Octave frequency analyses showed differences among musicians. This study suggests that musicians are at risk for hearing loss. There is a need for more effective guidelines applicable to all countries, which should define standardized procedures for determining musician noise exposure and should allow exposure level normalization to the year, including different repertoires.
Matilde Rodrigues; MarisaAlexandra Freitas; MariaPaula Neves; ManuelaVieira Silva; Rodrigues Ma; Neves Mp; Silva Mv. Evaluation of the noise exposure of symphonic orchestra musicians. Noise and Health 2014, 16, 40 .
AMA StyleMatilde Rodrigues, MarisaAlexandra Freitas, MariaPaula Neves, ManuelaVieira Silva, Rodrigues Ma, Neves Mp, Silva Mv. Evaluation of the noise exposure of symphonic orchestra musicians. Noise and Health. 2014; 16 (68):40.
Chicago/Turabian StyleMatilde Rodrigues; MarisaAlexandra Freitas; MariaPaula Neves; ManuelaVieira Silva; Rodrigues Ma; Neves Mp; Silva Mv. 2014. "Evaluation of the noise exposure of symphonic orchestra musicians." Noise and Health 16, no. 68: 40.
Blooms of toxic cyanobacteria are becoming increasingly frequent, mainly due to water quality degradation. This work applied qPCR as a tool for early warning of microcystin(MC)-producer cyanobacteria and risk assessment of water supplies. Specific marker genes for cyanobacteria, Microcystis and MC-producing Microcystis, were quantified to determine the genotypic composition of the natural Microcystis population. Correlations between limnological parameters, pH, water temperature, dissolved oxygen and conductivity and MC concentrations as well as Microcystis abundance were assessed. A negative significant correlation was observed between toxic (with mcy genes) to non-toxic (without mcy genes) genotypes ratio and the overall Microcystis density. The highest proportions of toxic Microcystis genotypes were found 4–6 weeks before and 8–10 weeks after the peak of the bloom, with the lowest being observed at its peak. These results suggest positive selection of non-toxic genotypes under favorable environmental growth conditions. Significant positive correlations could be found between quantity of toxic genotypes and MC concentration, suggesting that the method applied can be useful to predict potential MC toxicity risk. No significant correlation was found between the limnological parameters measured and MC concentrations or toxic genotypes proportions indicating that other abiotic and biotic factors should be governing MC production and toxic genotypes dynamics. The qPCR method here applied is useful to rapidly estimate the potential toxicity of environmental samples and so, it may contribute to the more efficient management of water use in eutrophic systems.
António Martins; Cristiana Moreira; Micaela Vale; Marisa Freitas; Ana Regueiras; Agostinho Antunes; Vitor Vasconcelos. Seasonal Dynamics of Microcystis spp. and Their Toxigenicity as Assessed by qPCR in a Temperate Reservoir. Marine Drugs 2011, 9, 1715 -1730.
AMA StyleAntónio Martins, Cristiana Moreira, Micaela Vale, Marisa Freitas, Ana Regueiras, Agostinho Antunes, Vitor Vasconcelos. Seasonal Dynamics of Microcystis spp. and Their Toxigenicity as Assessed by qPCR in a Temperate Reservoir. Marine Drugs. 2011; 9 (10):1715-1730.
Chicago/Turabian StyleAntónio Martins; Cristiana Moreira; Micaela Vale; Marisa Freitas; Ana Regueiras; Agostinho Antunes; Vitor Vasconcelos. 2011. "Seasonal Dynamics of Microcystis spp. and Their Toxigenicity as Assessed by qPCR in a Temperate Reservoir." Marine Drugs 9, no. 10: 1715-1730.
Cyanobacteria are prokaryotic photosynthetic microorganisms that pose a serious threat to aquatic environments because they are able to form blooms under eutrophic conditions and produce toxins. Cylindrospermopsis raciborskii is a planktonic heterocystous filamentous cyanobacterium initially assigned to the tropics but currently being found in more temperate regions such as Portugal, the southernmost record for this species in Europe. Cylindrospermopsin originally isolated from C. raciborskii is a cytotoxic alkaloid that affects the liver, kidney, and other organs. It has a great environmental impact associated with cattle mortality and human morbidity. Aiming in monitoring this cyanobacterium and its related toxin, a shallow pond located in the littoral center of Portugal, Vela Lake, used for agriculture and recreational purposes was monitored for a 2-year period. To accomplish this, we used the real-time PCR methodology in field samples to quantify the variation of specific genetic markers with primers previously described characterizing total cyanobacteria (16S rRNA), C. raciborskii (rpoC1), and cylindrospermopsin synthetase gene (pks). The results report the high abundance of both cyanobacteria and C. raciborskii in Vela Lake, with C. raciborskii representing 0.4% to 58% of the total cyanobacteria population. Cylindrospermopsin synthetase gene was detected in one of the samples. We believe that with the approach developed in this study, it will be possible to monitor C. raciborskii population dynamics and seasonal variation, as well as the potential toxin production in other aquatic environments.
Cristiana Moreira; António Martins; Joana Azevedo; Marisa Freitas; Ana Regueiras; Micaela Vale; Agostinho Antunes; Vitor Vasconcelos. Application of real-time PCR in the assessment of the toxic cyanobacterium Cylindrospermopsis raciborskii abundance and toxicological potential. Applied Microbiology and Biotechnology 2011, 92, 189 -197.
AMA StyleCristiana Moreira, António Martins, Joana Azevedo, Marisa Freitas, Ana Regueiras, Micaela Vale, Agostinho Antunes, Vitor Vasconcelos. Application of real-time PCR in the assessment of the toxic cyanobacterium Cylindrospermopsis raciborskii abundance and toxicological potential. Applied Microbiology and Biotechnology. 2011; 92 (1):189-197.
Chicago/Turabian StyleCristiana Moreira; António Martins; Joana Azevedo; Marisa Freitas; Ana Regueiras; Micaela Vale; Agostinho Antunes; Vitor Vasconcelos. 2011. "Application of real-time PCR in the assessment of the toxic cyanobacterium Cylindrospermopsis raciborskii abundance and toxicological potential." Applied Microbiology and Biotechnology 92, no. 1: 189-197.