Microalgae are a potential source for various valuable chemicals for commercial applications ranging from nutraceuticals to fuels. This review aims to focus on microalgal as preservative potential to food chain. The m...Microalgae are a potential source for various valuable chemicals for commercial applications ranging from nutraceuticals to fuels. This review aims to focus on microalgal as preservative potential to food chain. The main compounds responsible for these properties, like carotenoids, phenolic compounds, antioxidant vitamins, sterols and polyunsaturated fatty acids are discussed because microalgae can be cultivated under controlled conditions to improve their production. We have listed several studies performed in recent years supporting the health benefits that most of these compounds can provide. Therefore, they may represent an excellent source of preservatives in food chain once their safety as a food supplement has been also confirmed.展开更多
Here we investigate the ocean-atmosphere coupling and the contribution of the Sea Surface Temperature (SST) variations in: 1) Brazil-Malvinas Confluence (BMC) region, 2) Southwest Atlantic Ocean and 3) Southern Brazil...Here we investigate the ocean-atmosphere coupling and the contribution of the Sea Surface Temperature (SST) variations in: 1) Brazil-Malvinas Confluence (BMC) region, 2) Southwest Atlantic Ocean and 3) Southern Brazil. Numerical simulations of the ECHAM5/MPI-OM coupled ocean-atmosphere model were used to analyze the changes in the seasonal trajectory of the extratropical cyclones, in terms of intensification of physical mechanisms and implications for future scenarios. The numerical experiment for the future scenario considered an atmospheric CO2 concentration of approximately 770 ppm, which represents an increment of more than 350 ppm over the current values recorded by the Mauna Loa reference station. For this scenario, the results indicated a Storm Tracks (ST) displacement of 5° latitude toward south and changes of the meridional transport of sensible heat, close to 50°S. The increase in SST induces ST intensification and consequently an increase in the occurrence of extratropical cyclones. Overall, in the BMC region, we found a change in the pattern of cyclogenetic activity occurrence, with less frequent, but more intense events. On the Southern Brazilian region, the results of this study indicate increases in rainfall during summer months, whereas, a decrease in frequency and an increase in intensity were found for wintertime. We suggest that these changes could impact the climate dynamic of the Brazilian South coast, with a magnitude yet unknown.展开更多
This paper presents a study of biodiesel production by a non-catalytical process. The innovation in this study is the use of novel materials for production: seed soybean (Glycine Max) “in natura” and ethanol in a su...This paper presents a study of biodiesel production by a non-catalytical process. The innovation in this study is the use of novel materials for production: seed soybean (Glycine Max) “in natura” and ethanol in a supercritical state. To conduct the experiments, a bench reactor with a capacity of 150 mL, resistant to pressure of up to 300 bar and temperature of 350°C was developed. The fractional factorial experimental design () was used to evaluate the temperature, seed granulometry, molar ratio ethanol/oil and water percent of the mixture. The best yield observed was that of 94.07%, 10 minutes after the reactor entered a supercritical condition. Significant effects on seed granulometry, molar ratio ethanol, oil and temperature were verified. From the proposed process, biodiesel and toasted soybean seed were obtained. To purify the biodiesel sample it was necessary to use ultra-centrifugation to separate seed particles, and rotoevaporation to separate the fatty acid ethyl ester and unreacted ethanol. The chemical analyses were conducted directly by gas chromatography. The yield was calculated in accordance with concentrations obtained in the chromatographic analysis and seed mass of the experiment. Also checked was the presence of palmitate esters, stearate, oleate, linoleate and linolenate. By analyzing the ester composition it was possible to assess whether a good quality biodiesel was available. The roasted soybean seeds obtained after the reaction showed a calorific potential of 2203.17 kcal/kg and also be used as fuel.展开更多
Background The Cerrado is the most biodiverse savanna and maintains other biomes.Aware of its significance,this paper evaluated the Brazilian Cerrado’s climatic,environmental,and socioeconomic aspects using remote se...Background The Cerrado is the most biodiverse savanna and maintains other biomes.Aware of its significance,this paper evaluated the Brazilian Cerrado’s climatic,environmental,and socioeconomic aspects using remote sensing data and spatial statistics(correlation analysis and principal components analysis—PCA).Following the measures of sample adequacy(MSA)and Kaiser–Meyer–Olkin(KMO)tests,seventeen variables were evaluated.Results The MSA revealed that the dataset had a good quality(0.76),and nine variables were selected:elevation,evapotranspiration,active fires,Human Development Index(HDI),land use and land cover(LULC;shrubland and cropland/rainfed),rainfall(spring and autumn),and livestock.The correlation matrix indicated a positive(negative)association between HDI and autumn rainfall(HDI and active fires)with a value of 0.77(-0.55).The PCA results determined which three principal components(PC)were adequate for extracting spatial patterns,accounting for 68.02%of the total variance with respective values of 38.59%,16.89%,and 12.5%.Due to economic development and agribusiness,Cerrado’s northern(central,western,and southern)areas had negative(positive)score HDI values,as shown in PC1.Climatic(rainfall—spring and fall)and environmental(cropland/rainfed and shrubland)aspects dominated the PC2,with negative scores in northern and western portions due to the transition zone between Amazon and Cerrado biomes caused by rainfall variability.On the other hand,environmental aspects(LULC-shrubland and elevation)influenced the PC3;areas with high altitudes(>500 m)received a higher score.Conclusion Agricultural expansion substantially affected LULC,leading to deforestation-caused suppression of native vegetation.展开更多
文摘Microalgae are a potential source for various valuable chemicals for commercial applications ranging from nutraceuticals to fuels. This review aims to focus on microalgal as preservative potential to food chain. The main compounds responsible for these properties, like carotenoids, phenolic compounds, antioxidant vitamins, sterols and polyunsaturated fatty acids are discussed because microalgae can be cultivated under controlled conditions to improve their production. We have listed several studies performed in recent years supporting the health benefits that most of these compounds can provide. Therefore, they may represent an excellent source of preservatives in food chain once their safety as a food supplement has been also confirmed.
文摘Here we investigate the ocean-atmosphere coupling and the contribution of the Sea Surface Temperature (SST) variations in: 1) Brazil-Malvinas Confluence (BMC) region, 2) Southwest Atlantic Ocean and 3) Southern Brazil. Numerical simulations of the ECHAM5/MPI-OM coupled ocean-atmosphere model were used to analyze the changes in the seasonal trajectory of the extratropical cyclones, in terms of intensification of physical mechanisms and implications for future scenarios. The numerical experiment for the future scenario considered an atmospheric CO2 concentration of approximately 770 ppm, which represents an increment of more than 350 ppm over the current values recorded by the Mauna Loa reference station. For this scenario, the results indicated a Storm Tracks (ST) displacement of 5° latitude toward south and changes of the meridional transport of sensible heat, close to 50°S. The increase in SST induces ST intensification and consequently an increase in the occurrence of extratropical cyclones. Overall, in the BMC region, we found a change in the pattern of cyclogenetic activity occurrence, with less frequent, but more intense events. On the Southern Brazilian region, the results of this study indicate increases in rainfall during summer months, whereas, a decrease in frequency and an increase in intensity were found for wintertime. We suggest that these changes could impact the climate dynamic of the Brazilian South coast, with a magnitude yet unknown.
基金supported by CNPq,National Council for Scientific and Technological Development,Brazil
文摘This paper presents a study of biodiesel production by a non-catalytical process. The innovation in this study is the use of novel materials for production: seed soybean (Glycine Max) “in natura” and ethanol in a supercritical state. To conduct the experiments, a bench reactor with a capacity of 150 mL, resistant to pressure of up to 300 bar and temperature of 350°C was developed. The fractional factorial experimental design () was used to evaluate the temperature, seed granulometry, molar ratio ethanol/oil and water percent of the mixture. The best yield observed was that of 94.07%, 10 minutes after the reactor entered a supercritical condition. Significant effects on seed granulometry, molar ratio ethanol, oil and temperature were verified. From the proposed process, biodiesel and toasted soybean seed were obtained. To purify the biodiesel sample it was necessary to use ultra-centrifugation to separate seed particles, and rotoevaporation to separate the fatty acid ethyl ester and unreacted ethanol. The chemical analyses were conducted directly by gas chromatography. The yield was calculated in accordance with concentrations obtained in the chromatographic analysis and seed mass of the experiment. Also checked was the presence of palmitate esters, stearate, oleate, linoleate and linolenate. By analyzing the ester composition it was possible to assess whether a good quality biodiesel was available. The roasted soybean seeds obtained after the reaction showed a calorific potential of 2203.17 kcal/kg and also be used as fuel.
基金The authors thank CNPq and CAPES(Financial Code 001)for their scholarship awardsThis article was developed during the Post-Doctorate Junior scholarship of no.161023/2019-3 granted by Brazilian National Council for Scientific and Technological Development(CNPq)at the first authorThe second author thanks CNPq for granting the Research Productivity Fellowship level 2(309681/2019-7).
文摘Background The Cerrado is the most biodiverse savanna and maintains other biomes.Aware of its significance,this paper evaluated the Brazilian Cerrado’s climatic,environmental,and socioeconomic aspects using remote sensing data and spatial statistics(correlation analysis and principal components analysis—PCA).Following the measures of sample adequacy(MSA)and Kaiser–Meyer–Olkin(KMO)tests,seventeen variables were evaluated.Results The MSA revealed that the dataset had a good quality(0.76),and nine variables were selected:elevation,evapotranspiration,active fires,Human Development Index(HDI),land use and land cover(LULC;shrubland and cropland/rainfed),rainfall(spring and autumn),and livestock.The correlation matrix indicated a positive(negative)association between HDI and autumn rainfall(HDI and active fires)with a value of 0.77(-0.55).The PCA results determined which three principal components(PC)were adequate for extracting spatial patterns,accounting for 68.02%of the total variance with respective values of 38.59%,16.89%,and 12.5%.Due to economic development and agribusiness,Cerrado’s northern(central,western,and southern)areas had negative(positive)score HDI values,as shown in PC1.Climatic(rainfall—spring and fall)and environmental(cropland/rainfed and shrubland)aspects dominated the PC2,with negative scores in northern and western portions due to the transition zone between Amazon and Cerrado biomes caused by rainfall variability.On the other hand,environmental aspects(LULC-shrubland and elevation)influenced the PC3;areas with high altitudes(>500 m)received a higher score.Conclusion Agricultural expansion substantially affected LULC,leading to deforestation-caused suppression of native vegetation.