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Entre saberes e discursos: percepções de graduandos sobre a crise climática e educação ambiental
(Universidade Federal de São Carlos, 2025-06-10) Bernardes, Giovana; Santos, Mariana dos; https://lattes.cnpq.br/3185238960982642; https://orcid.org/0000-0002-1834-5467
This study investigates the perceptions of undergraduate and recently graduated students from the Federal University of São Carlos (UFSCar) regarding the climate crisis and Environmental Education, analyzing how these themes are addressed in their academic training and their impact on awareness and professional engagement. The research aimed to understand the tensions between development, social justice, and sustainability from the students’ perspective, through semi-structured interviews with 10 participants from different programs (including both environmental and non-environmental fields). Employing Discursive Textual Analysis (DTA) methodology, meaning units were constructed to better represent the ideas shared by participants, which were crucial for the subsequent elaboration of a metatext. Data analysis revealed that, although there is an awareness of the seriousness of the climate crisis, feelings of hopelessness and powerlessness predominate, exacerbated by the perception of political inaction and the difficulty of envisioning effective solutions in the current context. Eco-anxiety—a psychological distress generated by environmental degradation—emerged as a relevant phenomenon, even if rarely explicitly named by the interviewees. Regarding academic training, the findings point to an insufficient approach to Environmental Education within curricula, even in programs directly related to the field, where participants highlighted the importance of integrating the theme transversally, connecting it to their professional and social realities. The study concludes that, although there is recognition of the urgency of the climate crisis, a gap persists between awareness and practical action, both at individual and institutional levels. The university, as a space for critical education, holds the potential to foster change but must rethink its curriculum to address the socio-environmental challenges of the 21st century. For future studies, a more in-depth analysis of curriculum greening and the impacts of eco-anxiety on collective mobilization is recommended.
Tratamento ácido na fermentação etanólica: efeito sobre a viabilidade e vitalidade de linhagens industriais de Saccharomyces cerevisiae
(Universidade Federal de São Carlos, 2025-06-10) Jesus, Gabriel Scanavachi de; Ceccato-Antonini, Sandra Regina; https://lattes.cnpq.br/7600793543184032; https://lattes.cnpq.br/7227397272783828; Ceccato-Antonini, Sandra Regina; Bastos, Reinaldo Gaspar; Costa, Marcelo Augusto de Souza; https://lattes.cnpq.br/7600793543184032; https://lattes.cnpq.br/9329363278429665; https://lattes.cnpq.br/4776573073140781
The control of contaminant microorganisms in Brazilian sugar-ethanol industries frequently involves the use of sulfuric acid, which, when applied at the end of each fermentation cycle, not only controls contaminant bacteria but also promotes deflocculation of the yeast, contributing to ethanol production efficiency. Few studies have investigated the effect of acid treatment on the yeasts responsible for the fermentative process, particularly regarding viability — understood as the proportion of living cells capable of reproduction — and vitality — defined as the functional and physiological capacity of cells to carry out metabolic activities. In this study, we evaluated the effect of sulfuric acid treatment (pH 2.5; 2 h) on the viability and vitality of Saccharomyces cerevisiae cells, using the industrial strains PE-2 and CAT-1 in fed-batch fermentation with cell recycling, in sugarcane broth, over six fermentation cycles. We analyzed CFU/mL, number of viable cells/mL (erythrosine staining), viability (%), budding (%), growth in liquid medium and counting of bud scars, as well as alcohol content (g/100 mL), final pH, residual total reducing sugars (g/100 mL) and yield (g ethanol/g total reducing sugars) after each cycle of cell treatment. A control fermentation without acid treatment was also conducted, using water in place of the acid. In the PE-2 strain, acid treatment significantly affected viability (%), budding (%), specific growth rate (μmax, h⁻¹) and change in absorbance. However, fermentative yield was not compromised by the acid treatment, suggesting an adaptive profile capable of sustaining fermentative capacity; in contrast, the CAT-1 strain showed greater sensitivity to acid stress, with effects on budding (%), alcohol content (g/100 mL) and sugar consumption (g/100 mL). The increase in budding occurred concomitantly with accumulation of residual sugars and reduction in yield, indicating a prioritization of survival and cell division at the expense of fermentative efficiency. Moreover, analysis of bud scars revealed evidence of selection for metabolically active cells accompanied by death of young cells, a behavior that did not vary markedly between strains or treatments. Taken together, these results indicate that, although the CAT-1 strain persists across cycles, it exhibits a lower fermentative yield than PE-2 in the presence of acid treatment, probably due to lower tolerance to the acid treatment and a stronger mobilization of growth strategies to maintain cell viability during fermentation.