The genus Metadinophysis was proposed by Nie & Wang (1941) based on their description of the new ... more The genus Metadinophysis was proposed by Nie & Wang (1941) based on their description of the new species Metadinophysis sinensis Nie & Wang, from collections in Ching-lan Bay, Hainan Province, China. In addition to the Pacific Ocean, coastal waters of Japan, Thailand, and Vietnam, the genus was recorded for the southern coast of Myanmar (Su-Myat et al. 2012) and more recently in New Caledonia (Chomérat 2016). The present study constitutes the first record of Metadinophysis sinensis for the tropical Atlantic Ocean, from collections made in five coastal systems located in the coast of Bahia (13°01’30” S and 038°34’40” W, 13°52’44” S and 038°57’58” W), northeastern Brazil (Fig. 1).
The phytoplankton community is the first link in the aquatic trophic chain and knowledge of its c... more The phytoplankton community is the first link in the aquatic trophic chain and knowledge of its composition is an important tool for ecological characterization; including as potential indicator of anthropic impacts. The southern coast of Bahia is one of the best preserved parts of the Brazilian coast, however, little is known about its biodiversity, especially on marine phycoflora. With the objective of characterizing the composition of microphytoplankton (> 20 µm) in this region, samples were collected by a horizontal dredger using a plankton net (20 µm mesh size) to study the community composition. Water samples were taken from the subsurface using a Van Dorn bottle in order to analyze phytoplanktonic cell concentration. A total of 149 taxa were identified, distributed in the following phyla: Bacillariophyta, Miozoa, Cyanobacteria, Euglenophyta, Haptophyta, and Ochrophyta. Diatoms (63%) and dinoflagellates (26%) were the most representative groups in the specific composition. ...
Hypnea pseudomusciformis was recently described from South America, and has three morphological v... more Hypnea pseudomusciformis was recently described from South America, and has three morphological variants: "musciformis", "nigrescens", and "valentiae". Information on the biology of these variants may help to explain this species' wide morphological variation despite the absence of genetic divergence among variants. More morphological and ecological data has accumulated on the "musciformis" variant occurring on the Brazilian coast than for the others. In this study, we described the reproductive morphology of a tropical "nigrescens" population and investigated its phenology to provide crucial biological information about this taxon, and perhaps also assist in answering questions about the systematics of H. pseudomusciformis variants. The population analyzed showed no significant fluctuations in its total biomass throughout the year. All reproductive stages were frequently recorded during this study, which contributes greatly to our knowledge of the reproductive morphology of the "nigrescens" variant. Phenological variations were correlated with environment variables, such as air and sea-surface temperatures, insolation, precipitation, and humidity. Male gametophytes were frequently present, which has never been reported for the "musciformis" variant. We showed that, despite being members of the same genetic species, the "nigrescens" and "musciformis" morphological variants exhibit remarkable differences in their ecology and biology.
Revista Intertox de Toxicologia, Risco Ambiental e Sociedade
Consumption or contact with contaminated water reservoirs can trigger various health problems, co... more Consumption or contact with contaminated water reservoirs can trigger various health problems, considering the high number of waterborne diseases and the various uses of water. Among the most studied pathogens stands out the total and thermotolerant coliforms which, coupled to the evaluation of physical and chemical characteristics of the water body are tools widely used to characterize environmental conditions of the water and evaluate the possible consequences of its use by humans. Within this context it is presented in this work an assessment of the most probable number of total and fecal coliforms and water physic-chemical variables (Biochemical Oxygen Demand, Chemical Oxygen Demand, pH and turbidity) of Lake of the Friars, a pond city located in the municipality of Salvador-Bahia, focusing particularly on the public health problem imposed by water pollution of ponds used for recreation.
Revista Intertox de Toxicologia, Risco Ambiental e Sociedade
The toxins produced by some species of cyanobacteria secondary metabolites are of great importanc... more The toxins produced by some species of cyanobacteria secondary metabolites are of great importance in the context of public health in view of the risks that these toxins offer both to human health when they run into water bodies used for supply. In general there are four groups of cyanotoxins, classified according to their action in the body and target organ affected. The neurotoxins act on the nervous system by blocking the transmission of the signal neuron-neuron. Hepatotoxins act on the cytoskeleton of hepatocytes leading to loss of liver function. There is evidence that the action of sublethal doses of hepatotoxins was associated with the development of liver cancer. The dermatotoxins are related to cases of contact dermatitis related to the occurrence of microalgae producing dermatoxinas, especially in recreational water use. Cytotoxins, in turn, form a group of cyanotoxins intermediate with a chemical structure similar to neurotoxins and causing symptoms similar to those caused by hepatotoxins. In this paper seeks to discuss the importance of knowledge about the species forming toxic metabolites and their sources of supply monitoring in order to control the risks that they offer to the public health.
This study assessed the species composition, distribution, and functional profiles of cyanobacter... more This study assessed the species composition, distribution, and functional profiles of cyanobacteria in Camamu Bay, a tropical oligotrophic estuarine system on the northeast coast of Brazil, using shotgun metagenomic sequencing. Surface-water samples were evaluated in two different rainfall periods (rainy and dry seasons), at nine stations in the three hydrodynamic regions of the bay. At a fixed sampling station, on each season, samples were taken over a tidal cycle at 3-h intervals over 12 h. A total of 219 cyanobacterial taxa were identified, demonstrating a diverse community of freshwater, euryhaline, and marine cyanobacteria. The genera of greater relative abundance, and , corresponded to the picoplankton fraction. Although Camamu Bay has conspicuous marine characteristics, the contribution of freshwater during the rainy season caused variation in cyanobacteria community, with an increase in species richness. Due the high prevalence of (90% of the sequences), the functional analy...
The accumulation of exopolysaccharides (EPS) produced by microorganisms occurs in the presence of... more The accumulation of exopolysaccharides (EPS) produced by microorganisms occurs in the presence of excess substrate and limiting conditions of elements that are essential to growth, such as nitrogen, phosphorus, sulfur, and magnesium. The presence of EPS produced by bacterial cells contributes to slime colonies formation in solid medium and increased viscosity in liquid medium. This paper proposes an alternative method for screening EPS-producing lactic acid bacteria using solid medium-containing discs of filter paper that are saturated with active cultures. The screening was carried out under different culture conditions varying the type of sugar, pH, and temperature. EPS production was visualized by the presence of mucoid colonies on the discs, which was confirmed by the formation of a precipitate when part of this colony was mixed with absolute alcohol. The established conditions for obtaining a high number of isolates producing EPS were 10% sucrose, pH 7.5 and 28 ºC. This method ...
A bloom of Trichodesmium erythraeum with average densities of 3.5 x 10 6 trichomes L-1 was record... more A bloom of Trichodesmium erythraeum with average densities of 3.5 x 10 6 trichomes L-1 was recorded in February 2014, in an extensive range of beaches on the northern coast of Bahia, Brazil. High water temperatures and rainfall, associated with wind frequency and intensity may have triggered the bloom, which lead to a strong odor and change in the color of the water, it obliged the authorities to shut down the affected beaches. These blooms negatively affected tourism and fishing, the main economic activities in the region, highlighting the importance of monitoring these events in the area.
The genus Metadinophysis was proposed by Nie & Wang (1941) based on their description of the new ... more The genus Metadinophysis was proposed by Nie & Wang (1941) based on their description of the new species Metadinophysis sinensis Nie & Wang, from collections in Ching-lan Bay, Hainan Province, China. In addition to the Pacific Ocean, coastal waters of Japan, Thailand, and Vietnam, the genus was recorded for the southern coast of Myanmar (Su-Myat et al. 2012) and more recently in New Caledonia (Chomérat 2016). The present study constitutes the first record of Metadinophysis sinensis for the tropical Atlantic Ocean, from collections made in five coastal systems located in the coast of Bahia (13°01’30” S and 038°34’40” W, 13°52’44” S and 038°57’58” W), northeastern Brazil (Fig. 1).
The phytoplankton community is the first link in the aquatic trophic chain and knowledge of its c... more The phytoplankton community is the first link in the aquatic trophic chain and knowledge of its composition is an important tool for ecological characterization; including as potential indicator of anthropic impacts. The southern coast of Bahia is one of the best preserved parts of the Brazilian coast, however, little is known about its biodiversity, especially on marine phycoflora. With the objective of characterizing the composition of microphytoplankton (> 20 µm) in this region, samples were collected by a horizontal dredger using a plankton net (20 µm mesh size) to study the community composition. Water samples were taken from the subsurface using a Van Dorn bottle in order to analyze phytoplanktonic cell concentration. A total of 149 taxa were identified, distributed in the following phyla: Bacillariophyta, Miozoa, Cyanobacteria, Euglenophyta, Haptophyta, and Ochrophyta. Diatoms (63%) and dinoflagellates (26%) were the most representative groups in the specific composition. ...
Hypnea pseudomusciformis was recently described from South America, and has three morphological v... more Hypnea pseudomusciformis was recently described from South America, and has three morphological variants: "musciformis", "nigrescens", and "valentiae". Information on the biology of these variants may help to explain this species' wide morphological variation despite the absence of genetic divergence among variants. More morphological and ecological data has accumulated on the "musciformis" variant occurring on the Brazilian coast than for the others. In this study, we described the reproductive morphology of a tropical "nigrescens" population and investigated its phenology to provide crucial biological information about this taxon, and perhaps also assist in answering questions about the systematics of H. pseudomusciformis variants. The population analyzed showed no significant fluctuations in its total biomass throughout the year. All reproductive stages were frequently recorded during this study, which contributes greatly to our knowledge of the reproductive morphology of the "nigrescens" variant. Phenological variations were correlated with environment variables, such as air and sea-surface temperatures, insolation, precipitation, and humidity. Male gametophytes were frequently present, which has never been reported for the "musciformis" variant. We showed that, despite being members of the same genetic species, the "nigrescens" and "musciformis" morphological variants exhibit remarkable differences in their ecology and biology.
Revista Intertox de Toxicologia, Risco Ambiental e Sociedade
Consumption or contact with contaminated water reservoirs can trigger various health problems, co... more Consumption or contact with contaminated water reservoirs can trigger various health problems, considering the high number of waterborne diseases and the various uses of water. Among the most studied pathogens stands out the total and thermotolerant coliforms which, coupled to the evaluation of physical and chemical characteristics of the water body are tools widely used to characterize environmental conditions of the water and evaluate the possible consequences of its use by humans. Within this context it is presented in this work an assessment of the most probable number of total and fecal coliforms and water physic-chemical variables (Biochemical Oxygen Demand, Chemical Oxygen Demand, pH and turbidity) of Lake of the Friars, a pond city located in the municipality of Salvador-Bahia, focusing particularly on the public health problem imposed by water pollution of ponds used for recreation.
Revista Intertox de Toxicologia, Risco Ambiental e Sociedade
The toxins produced by some species of cyanobacteria secondary metabolites are of great importanc... more The toxins produced by some species of cyanobacteria secondary metabolites are of great importance in the context of public health in view of the risks that these toxins offer both to human health when they run into water bodies used for supply. In general there are four groups of cyanotoxins, classified according to their action in the body and target organ affected. The neurotoxins act on the nervous system by blocking the transmission of the signal neuron-neuron. Hepatotoxins act on the cytoskeleton of hepatocytes leading to loss of liver function. There is evidence that the action of sublethal doses of hepatotoxins was associated with the development of liver cancer. The dermatotoxins are related to cases of contact dermatitis related to the occurrence of microalgae producing dermatoxinas, especially in recreational water use. Cytotoxins, in turn, form a group of cyanotoxins intermediate with a chemical structure similar to neurotoxins and causing symptoms similar to those caused by hepatotoxins. In this paper seeks to discuss the importance of knowledge about the species forming toxic metabolites and their sources of supply monitoring in order to control the risks that they offer to the public health.
This study assessed the species composition, distribution, and functional profiles of cyanobacter... more This study assessed the species composition, distribution, and functional profiles of cyanobacteria in Camamu Bay, a tropical oligotrophic estuarine system on the northeast coast of Brazil, using shotgun metagenomic sequencing. Surface-water samples were evaluated in two different rainfall periods (rainy and dry seasons), at nine stations in the three hydrodynamic regions of the bay. At a fixed sampling station, on each season, samples were taken over a tidal cycle at 3-h intervals over 12 h. A total of 219 cyanobacterial taxa were identified, demonstrating a diverse community of freshwater, euryhaline, and marine cyanobacteria. The genera of greater relative abundance, and , corresponded to the picoplankton fraction. Although Camamu Bay has conspicuous marine characteristics, the contribution of freshwater during the rainy season caused variation in cyanobacteria community, with an increase in species richness. Due the high prevalence of (90% of the sequences), the functional analy...
The accumulation of exopolysaccharides (EPS) produced by microorganisms occurs in the presence of... more The accumulation of exopolysaccharides (EPS) produced by microorganisms occurs in the presence of excess substrate and limiting conditions of elements that are essential to growth, such as nitrogen, phosphorus, sulfur, and magnesium. The presence of EPS produced by bacterial cells contributes to slime colonies formation in solid medium and increased viscosity in liquid medium. This paper proposes an alternative method for screening EPS-producing lactic acid bacteria using solid medium-containing discs of filter paper that are saturated with active cultures. The screening was carried out under different culture conditions varying the type of sugar, pH, and temperature. EPS production was visualized by the presence of mucoid colonies on the discs, which was confirmed by the formation of a precipitate when part of this colony was mixed with absolute alcohol. The established conditions for obtaining a high number of isolates producing EPS were 10% sucrose, pH 7.5 and 28 ºC. This method ...
A bloom of Trichodesmium erythraeum with average densities of 3.5 x 10 6 trichomes L-1 was record... more A bloom of Trichodesmium erythraeum with average densities of 3.5 x 10 6 trichomes L-1 was recorded in February 2014, in an extensive range of beaches on the northern coast of Bahia, Brazil. High water temperatures and rainfall, associated with wind frequency and intensity may have triggered the bloom, which lead to a strong odor and change in the color of the water, it obliged the authorities to shut down the affected beaches. These blooms negatively affected tourism and fishing, the main economic activities in the region, highlighting the importance of monitoring these events in the area.
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