Banca de QUALIFICAÇÃO: JOSIEL SANTOS DO NASCIMENTO

Uma banca de QUALIFICAÇÃO de DOUTORADO foi cadastrada pelo programa.
STUDENT : JOSIEL SANTOS DO NASCIMENTO
DATE: 27/12/2023
TIME: 13:30
LOCAL: Vìdeoconferência
TITLE:

PLANT SERINE PROTEASE: CHARACTERIZATION AND BIOTECHNOLOGICAL APPLICATION

KEY WORDS:

L. leucocephala, coagulant, characterization

PAGES: 52
BIG AREA: Ciências Biológicas
AREA: Bioquímica
SUMMARY:

The application of enzymes in biotechnological processes allows for a significant reduction in costs with a consequent reduction in energy consumption. In this context, proteases are the most produced biomolecules and represent 60% of all enzymes sold in the world. The importance of using these molecules is due to factors such as high catalytic activity, selectivity, specificity, as well as production variability. Given the demand to produce studies aimed at obtaining enzymes with an industrial bias, the aim of this work is to obtain a protease of biotechnological interest from the seeds of Leucaena leucocephala, following its characterization and application. The project's starting point was to investigate the enzymatic activity in the crude extract of L. leucocephala seeds. Through this research, it was possible to describe a new milk coagulant. The optimal enzyme activities were determined at 40ºC and pH 9.0. In stability tests, the enzyme remained stable over a wide range of pH (5.0 to 9.0) and temperatures (40ºC to 60ºC). Furthermore, the enzyme's catalytic activity improved in the presence of metal ions (Na+, K+, Mn2+, Mg2+ and Ca2+). The enzyme has demonstrated stability and compatibility with detergents, reducing agents and organic solvents. This highlights the biotechnological potential of this enzyme in various industrial processes. When the enzyme extract was subjected to different chromogenic substrates conjugated with p-nitroaniline, the hydrolysis showed specificity for BApNA. Furthermore, the enzyme was inhibited by PMSF (95.80%) followed by Benzamidine (84.22%). Therefore, the enzyme belongs to the serine protease class, an endopeptidase that preserves the presence of the amino acids serine, histidine and aspartic acid in its catalytic site. The aqueous extract of L. leucocephala seeds was subjected to toxicity testing using a bioindicator. It was possible to demonstrate that no toxic environment was generated after 24 hours of exposure of the crustaceans, Artemia salina, to different concentrations of the aqueous extract.

 

COMMITTEE MEMBERS:
Interno(a) - 2089586 - FRANCIS SOARES GOMES
Externo(a) à Instituição - JOHNNATAN DUARTE DE FREITAS - IFAL
Interno(a) - 1653558 - LUCIANO APARECIDO MEIRELES GRILLO