Banca de DEFESA: DÁVIDA MARIA RIBEIRO CARDOSO DOS SANTOS

Uma banca de DEFESA de DOUTORADO foi cadastrada pelo programa.
STUDENT : DÁVIDA MARIA RIBEIRO CARDOSO DOS SANTOS
DATE: 12/12/2022
TIME: 09:00
LOCAL: por videoconferência
TITLE:

Production, isolation, characterization and biotechnological application of endoglucanase from the filamentous fungus Pycnosporus sanguineus

KEY WORDS:

Agroindustrial waste, filamentous fungi, endoglucanase, purification, characterization and biotechnology.

PAGES: 89
BIG AREA: Ciências Biológicas
AREA: Bioquímica
SUBÁREA: Química de Macromoléculas
SPECIALTY: Proteínas
SUMMARY:

The growth of the world population increased investment in agribusiness and,

consequently, increased the generation of agroindustrial residues, mostly

lignocellulosic. Clean alternatives for the use of agro-industrial residues have been

researched around the world, among them is the use of residues as a source for

fungal growth for the production of enzymes of biotechnological interest. The

objectives of this work were to produce, isolate, characterize and biotechnologically

apply the endoglucanase produced from the filamentous fungus Pycnoporus

sanguineus. Five different agro-industrial residues (wheat bran, sugarcane bagasse,

wood powder, coconut fiber and filter paper) were used by solid state fermentation

(FES). The enzyme was isolated through ethanol fractionation and ion exchange

chromatography, the isolation was confirmed by (SDS-PAGE) in reducing and

denaturing conditions. The isolated endoglucanase was characterized for

temperature, pH, halotolerance, enzymatic kinetics and applied biotechnologically

through the saccharification of agro-industrial residues. Endoglucanase production

was higher in wheat bran (72 hs). The 80-100% fraction of the ethanol fractionation

concentrated greater enzymatic activity and was subjected to ion exchange

chromatography (DEAE-Sepharose), the isolated enzyme was eluted in a single

fraction, as confirmed by SDS-PAGE. The optimal temperature of the isolated

endoglucanase was 50°C and the thermal stability was between 20° and 60°C with

up to 50% of the enzymatic activity, temperatures compatible with other fungal

endoglucanases. The optimum pH was pH 5.0, with stability at pH between pH 4.5

and 8.0, demonstrating stability at slightly alkaline pH compatible with

biotechnological applications in the detergent industry. The isolated enzyme

remained viable with activity greater than 100% in up to 5 M NaCl, an important

characteristic because some industrial processes take place in the presence of large

amounts of NaCl. The enzyme presented Km 3.18 ± 100 mg/mL and the Kcat equal

to 4.53 S-1 and managed to produce 273 mg/mL reducing sugars in 24 hours in rice

husks, proving to be viable for the production of second-generation ethanol . The

present work concluded that the fungus P. sanguineus is a producer of an

endoglucanase with important biochemical characteristics, fast production and low

cost.

BANKING MEMBERS:
Interno(a) - 2089586 - FRANCIS SOARES GOMES
Presidente - 1811274 - HUGO JUAREZ VIEIRA PEREIRA
Interno(a) - 1653558 - LUCIANO APARECIDO MEIRELES GRILLO
Externo(a) ao Programa - 1294906 - RUTH RUFINO DO NASCIMENTO
Externo(a) ao Programa - 166.228.474-87 - SONIA SALGUEIRO MACHADO - UFAL