Banca de QUALIFICAÇÃO: BEATRIZ DE AZEVEDO

Uma banca de QUALIFICAÇÃO de MESTRADO foi cadastrada pelo programa.
STUDENT : BEATRIZ DE AZEVEDO
DATE: 03/03/2022
TIME: 09:00
LOCAL: Via Google Meet
TITLE:

Production of celulases ande xylanases by a new fungal species – A. lippiae URM 7547 – using a green coconut fiver pre-treated by steam explosion. 

KEY WORDS:

Endophytic fungus, green coconut fiber, submerged fermentation, enzymes.

PAGES: 93
BIG AREA: Engenharias
AREA: Engenharia Química
SUBÁREA: Processos Industriais de Engenharia Química
SPECIALTY: Processos Bioquímicos
SUMMARY:

Endophytes, which can be bacteria, fungi, and protozoa, are poorly studied. It is estimated that there are more than 250,000 different species of plants, and one million endophytes in the world, which characterizes an average of four different species associated with a plant species. Because they are inside the plant, these microorganisms can be a rich source of bioactive secondary metabolites, such as the production of lignocellulolytic enzymes. In this context, this study aims to study the ability of a new endophytic fungal species, Achaetomium lippiae URM 7547, to produce cellulases and xylanases by means of a submerged culture using as substrate the fiber of the green coconut husk pre-treated in a steam explosion. Initially, the potential of A. lippiae URM 7547 to produce hydrolases (amylase, lipase, protease, cellulase, xylanase and pectinase) was evaluated in a solid culture medium (72h at 30°C) with substrates that induce each specific enzyme. The yield of substrate conversion into cell biomass (Y_x/s) of A. lippiae URM 7547 and its maximum growth rate (µ_max) were also quantified in liquid medium containing glucose and xylose and different nutrient media. Finally, the submerged fermentation began to produce cellulases and xylanases. In solid medium cultivation, A. lippiae URM 7547 presented itself as a potential producer of amylases, proteases, and cellulases, with an enzymatic index greater than 1.5 (EI > 1.5). The best results for the liquid medium containing glucose were in 96h of culture in medium C, containing peptone and yeast extract, in which it obtained Yx/s equal to 0.062 ± 0.04 gg-1, 0.072 ± 0.04 g g^-1, and 0.076 ± 0.03 g g^-1, for concentrations of 5, 10 and 20 gL^-1 of the substrate, respectively. For the medium containing xylose, the best result was during 144h of cultivation with Y_x/s values qual to 0.52 ± 0.08, 0.59 ± 0.09 and 0.65 ± 0.03 g g^-1 for 5.0 , 10.0 and 20.0 gL^-1, respectively, also in C medium. The culture at 33°C with 109 spores.mL^-1 and 30.0 gL^-1 of substrate showed enzymatic activity (U.mL^-1) of 0.41 ± 0.06, 5.94 ± 0.31 and 0.08 ± 0.035 and 9.12 ± 0.28 for FPase, CMCase, Cellobiase and Xylanase, respectively. Thus, A. lippiae URM 7547 has a good potential for the production of hemicellulolytic enzymes.

BANKING MEMBERS:
Presidente - 1346198 - EVERALDO SILVINO DOS SANTOS
Externo ao Programa - 3652554 - FRANCISCO CANINDE DE SOUSA JUNIOR
Externo ao Programa - 080.862.344-36 - PEDRO FERREIRA DE SOUZA FILHO - UFRN
Externo ao Programa - 027.194.253-38 - SÉRGIO DANTAS DE OLIVEIRA JÚNIOR