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Estudo da ação antimicrobiana de Ga(NO3)3 em cepas bacterianas
(Universidade Federal de São Carlos, 2022-03-03) Assis, Amanda Stefanie Jabur de; Duarte, Iolanda Cristina Silveira; https://lattes.cnpq.br/2626035341263254; https://lattes.cnpq.br/3438650971860266
According to the World Health Organization in 2020, from all hospitalized patients, a share of cases are infections acquired in a hospital environment due to invasive procedures. For decades, Escherichia coli and Staphylococcus aureus strains have been reported as the main cause of hospital infections. In this way, these microorganisms have developed resistance to various medications over time, reducing the diversity of means to contain their action, highlighting the importance of developing new alternatives with antimicrobial properties. Thus, the use of gallium (Ga3+), which causes harmful effects to bacterial activities due to its characteristics and physicochemical properties similar to those of iron (Fe3+), leads to the possibility to regulate the growth of both planktonic forms and biofilms. Therefore, due to the antimicrobial potential of Ga3+ compounds, this work has performed serial microdilution tests in order to identify the minimum inhibitory concentration (MIC) capable of reducing the growth of representative strains of E. coli and S. aureus. It was possible to verify a reduction in the growth of these microorganisms at 11.25 μM and 1.40 μM of gallium nitrate (Ga(NO3)3), respectively. Thus, the concentrations obtained in this work were able to reduce 50% of the growth of tested microorganisms. This result showed that minor concentrations of Ga(NO3)3 were sufficient against nosocomial pathogens cultures when compared to the literature data.
Produção integrada de etanol de cana-de-açúcar e milho em usinas flex: simulação e análises tecno-econômica e ambiental
(Universidade Federal de São Carlos, 2022-03-03) Oliveira, Luiza Stolte Bezerra Lisbôa de; Cruz, Antonio José Gonçalves da; https://lattes.cnpq.br/1812806190521028; https://lattes.cnpq.br/5653079460114658
Liquid biofuels are important alternatives to traditional fossil fuels, not only environmentally, but also socially and from an energy security standpoint. Brazil has a consolidated infrastructure for the production, distribution, and commercialization of biofuels, in particular ethanol. Even though sugarcane has been the main raw material used for ethanol production for years, the processing of corn for ethanol production has been experiencing a rapid growth, especially in the Center-West region. This project evaluated the technical, economic and environmental feasibility of corn ethanol production integrated to a standalone sugarcane ethanol distillery (called flex plant). The standalone distillery processes 4 million tons of sugarcane in the harvest season, and one scenario considers cogeneration from sugarcane straw during the off-season. Two scenarios for corn ethanol production were studied: conventional (sequential liquefaction, saccharification and fermentation) and simultaneous (simultaneous saccharification and fermentation of non-liquefied starch), each processing about 246 and 208 thousand tons of corn in the off-season. The process simulator Aspen Plus was used to estimate capital costs and process yields. The incremental capital cost for the flex plants was 53,8 and 52,9 million dollars for the conventional and simultaneous scenarios, respectively, and the increase in anhydrous ethanol production, relative to the amount produced in the harvest season from sugarcane, was 25,2 and 21,3%. The NPV (Net Present Value) of the flex plants was 86,1 and 63,9 million dollars, following an incremental approach. However, the Maximum Purchase Price for Corn (MPPC) was around 58 R$/60kg, which is lower than the price in Mato Grosso for February 2022 (75 R$/60kg). The risk analysis indicated that the probability of profitability for the incremental flex plants is around 68%. The open software OpenLCA was used to perform the Life Cycle Assessment (LCA). The incorporation of corn ethanol production increased the impact in the global warming category by 6% (from 0,533 to 0,564 kg CO2 eq/kg ethanol), relative to the value obtained for the standalone distillery with cogeneration from straw. In addition, the impact on the freshwater ecotoxicity category was 6 to 7 times greater for the flex scenarios than for the standalone distillery, due to the high application of pesticides during corn cultivation. This suggests that improvements to this impact category should be made at the agricultural level.
Avaliação ecotoxicológica das águas do Rio Pirajibú por análises de biomarcadores em girinos de rã-touro, Lithobates catesbeianus (Shaw, 1802)
(Universidade Federal de São Carlos, 2022-03-03) Silva, Fábio Henrique da; Carvalho, Cleoni dos Santos; https://lattes.cnpq.br/7233550271936621; Duarte, Iolanda Cristina Silveira; https://lattes.cnpq.br/2626035341263254; https://lattes.cnpq.br/2923321279138963
In Sorocaba/SP, the Pirajibú river courses the industrial zone of the city, and receives the effluents discharge from several companies. This river is classified as class 2, according to the criteria defined by Brazilian environmental law (CONAMA nº 357/2005), and State of Sao Paulo environmental law (Decree nº 8468/1976). The classification, appearance and characteristics, indicates that Pirajibú water does not result in mortality to aquatic organisms, however, the sublethal or toxicological effects have not been studied yet. Considering this gap, the present study aimed to promote an ecotoxicological and water quality assessment of the Pirajibú river. To perform it, water collections were carried out in the river at upstream and downstream from the industrial zone. The water samples were subjected to analysis of physicochemical parameters. The ecotoxicological tests were carried out through the analysis of biomarkers in the liver of bullfrog tadpoles, exposed for 96 hours to the waters of the Pirajibú river. The biomarkers analyzed include reduced glutathione (GSH - tripeptide), glutathione peroxidase (GPx), glutathione S-transferase (GST), and the metabolites glucose, proteins and triglycerides. The metals and other physical chemical analyzes, indicated that the downstream of the industrial zone has a lower quality than the upstream point. Regarding the biomarkers analysis, the activity of the GPx enzyme was significantly lower in the upstream group (6.94 ± 0.99 nmol Nicotinamide Adenine Dinucleotide Phosphate - NADPH / min / mg protein) compared to the control (14.11± 4.88 nmol NADPH / min / mg protein), while GST had significantly higher activity in the downstream group (53.674 ± 11.47 nmol Tioéter / min / mg protein) compared to the control group (36.42 ± 7.98 nmol of nmol Tioéter / min / mg protein). In reference to others biomarkers, no significant changes were observed between the control organisms and those exposed to the waters of the Pirajibú river. This result demonstrated that exposure for 96 hours was not able to change most of the biomarkers evaluated, but not enough to rule out the potential of the waters of this river provide oxidative stress, and other sublethal effects in bullfrog tadpoles.