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1.
J Chem Educ ; 98(12): 3794-3803, 2021 Dec 14.
Artículo en Inglés | MEDLINE | ID: mdl-37556275

RESUMEN

The coronavirus COVID-19 pandemic required educational institutions to adapt face-to-face to remote teaching. This study reports the experience in the first semester of 2020 for a Chemical Engineering Capstone Design Course at the University of Campinas in Brazil. In this course, senior year students develop a group project, in which they simulate a chemical plant and evaluate its technoeconomic feasibility. In 2020, the groups were proposed to design a process to replace diesel fuel from the bus fleet in Campinas city with renewable fuel DME. Because of the pandemic, several adaptations were needed: the theoretical classes became asynchronous, group meetings were online, a commercial simulator was replaced by an open access one, and the schedule was extended by 2 weeks. Despite that, the students had a great performance, comparable to face-to-face. To assess student satisfaction, a questionnaire was used. The course met the expectations of most of the students who also recommended keeping it in the remote format or merging it with face-to-face teaching. Therefore, these changes made it possible to apply new teaching dynamics and tools that could be used in the future to improve the course quality.

2.
Braz. j. microbiol ; 40(4): 747-756, Oct.-Dec. 2009. graf, tab
Artículo en Inglés | LILACS | ID: lil-528156

RESUMEN

Gamma-linolenic acid (GLA, 18:3, cis- 6,9,12-octadecatrienoic acid), an important compound in n-6 eicosanoid family biosynthesis, occurs in the lipids of a few plant and microbial sources. This study focused on the screening of microbial strains with suitable lipase activity for enrichment of GLA by selective hydrolysis of the borage oil (21.6 percent of GLA/total fatty acids). Firstly, 352 microrganisms were tested for their lipolytic capacity using screening techniques on agar plates containing borage oil, strains were then selected and screened for their activity (U/mg) using both submerged fermentation (SmF) and solid state fermentation (SSF). The rate of hydrolysis and the selective preference of these hydrolytic enzymes towards fatty acids, with a special focus on enrichment of GLA were studied and compared with those obtained by two commercially-available lipases. Only one of the lipases tested during this study displayed selectivity, discriminating the GLA during the hydrolysis reaction. Using the enzymatic extract from Geotrichum candidum as a biocatalyst of the reaction, it was possible to obtain a percentage of 41.7 percent of GLA in acylglycerols fraction when the borage oil was treated in a fixed-bed reactor for 24 hours at 30ºC.


Asunto(s)
Ácido gammalinolénico/análisis , Ácido gammalinolénico/aislamiento & purificación , Borago , Fermentación , Geotrichum/enzimología , Geotrichum/aislamiento & purificación , Técnicas In Vitro , Lipasa/análisis , Lipasa/aislamiento & purificación , Catalizador , Activación Enzimática , Hidrólisis , Métodos , Métodos
3.
Braz J Microbiol ; 40(4): 747-56, 2009 Oct.
Artículo en Inglés | MEDLINE | ID: mdl-24031421

RESUMEN

Gamma linolenic acid (GLA, 18:3, cis- 6,9,12- octadecatrienoic acid), an important compound in n- 6 eicosanoid family biosynthesis, occurs in the lipids of a few plant and microbial sources. This study focused on the screening of microbial strains with suitable lipase activity for enrichment of GLA by selective hydrolysis of the borage oil (21.6 % of GLA/total fatty acids). Firstly, 352 microrganisms were tested for their lipolytic capacity using screening techniques on agar plates containing borage oil, strains were then selected and screened for their activity (U/mg) using both submerged fermentation (SmF) and solid state fermentation (SSF). The rate of hydrolysis and the selective preference of these hydrolytic enzymes towards fatty acids, with a special focus on enrichment of GLA were studied and compared with those obtained by two commercially-available lipases. Only one of the lipases tested during this study displayed selectivity, discriminating the GLA during the hydrolysis reaction. Using the enzymatic extract from Geotrichum candidum as a biocatalyst of the reaction, it was possible to obtain a percentage of 41.7% of GLA in acylglycerols fraction when the borage oil was treated in a fixed-bed reactor for 24 hours at 30ºC.

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