Banca de QUALIFICAÇÃO: VIVIANE HIROMI UCHIDA

Uma banca de QUALIFICAÇÃO de DOUTORADO foi cadastrada pelo programa.
STUDENT : VIVIANE HIROMI UCHIDA
DATE: 12/08/2021
TIME: 14:00
LOCAL: Via Google Meet
TITLE:

Use of Castanets (Terminalia catappa Linn) in the production of pectinases and cellulases by Solid State Fermentation (FES) using Aspergilus niger IOC 3998 and use of its bioactive compounds.

KEY WORDS:

Terminalia catappa Linn, bioactive compounds, enzyme inhibition, nanoemulsion, polygalacturonase, cellulases, solid state fermentation

PAGES: 122
BIG AREA: Engenharias
AREA: Engenharia Química
SUBÁREA: Processos Industriais de Engenharia Química
SPECIALTY: Processos Bioquímicos
SUMMARY:

Abstract: The castannet (Terminalia catappa Linn) is a well known tree in Brazil, however it is used for ornamental purposes, standing out for being well adapted to tropical climates. Castanets produce fruits in abundance and are edible, however, they have no commercial value. The fruit of the castannet has a large amount of phenolic compounds, thus being a source of antioxidant compounds. Despite the large amount of fruit that is produced by the tree, most studies with this plant are carried out with the leaves, however, little is addressed in relation to the fruits, which can be an opportunity to explore the fruit as a raw material to obtain products with higher added value, since the fruit has no commercial value, in addition to being an alternative to reduce the large amount of biomass (waste) discarded in urban centers. In this context, the use of solid state fermentation (FES), as it demands lower operating costs, materials and energy, becomes attractive. In this scenario, the castanna pulp extract was used to obtain phenolic compounds, evaluating their ability to inhibit the α-amylase enzyme. Then, the encapsulation was carried out by nanoemulsions of the bioactive compounds in 3 systems (F1, F2 and F3), from the extract, using acetone as the organic phase, distilled water as the aqueous phase and Tween as the emulsifier by the method of low energy emulsion inversion point (EIP). The pulp, after the extraction step, was used as substrate in the production of polygalacturonase and pectin lyase by FES using Aspergilus niger IOC 3998 using a 23 factorial design with triplicate at the central point which was used to evaluate the influence of temperature factors , pH and moisture in enzymatic activities. Finally, castanna fruit stone was also used to investigate the influence of pH and moisture factors on cellulase production (CMCase and FPase) also by FES using A. niger IOC 3998 using a central rotational composite design 22 with duplicate at the center point. The results showed that the extraction of phenolic compounds proved to have a good inhibition with 100% of the concentrated extract. For the encapsulation by nanoemulsions it was verified the formation of such systems with average diameters 109.6nm ± 2.7 for the F1, 62.4nm ± 1.5 for the F2 and 244.5nm ± 1.7 for the F3. The 23 factorial design with triplicate at the central point showed that pH and interactions, temperature with pH and temperature with humidity were significant in the model studied for polygalacturonase. While for pectin lyase, moisture as well as its interaction with temperature and pH were significant. The best values found in the fermentation process were 32.61 U/g (30°C, pH 8.0 and 80% humidity) and 189.91 U/g (30°C, pH 4.0 and 80% of moisture) for the polygalacturonase and pectin lyases, respectively. The temperature and pH stability of the enzymatic extract, for polygalacturonase and pectin lyase, was thermostable for all temperatures studied in the range 30 to 70°C. However, for stability at different pHs (4, 5, 6 and 7) the enzymatic extracts were not very stable, with polygalacturonase being more sensitive to pH change while pectin lyase maintained its stability up to 1h of incubation. For the central composite design 22 with duplicate at the central point, the results show that the treated residue (cellulose content 22.0%) had better yield in the production of cellulases, obtaining 13.2 U/g for CMCase and 0.232 U/g for FPase. Stability tests against pH and temperature showed that activities for CMCase and FPase performed better at neutral pH. In relation to temperature, it was observed that its increase reduced the activity of CMCase and FPase at temperatures above 50 °C. Thus, the present study demonstrates the potential use of the pulp and stone of the castannet fruit to obtain bioproducts with high added value.

BANKING MEMBERS:
Presidente - 1346198 - EVERALDO SILVINO DOS SANTOS
Externa ao Programa - 3214434 - NATHALIA SARAIVA RIOS
Externo ao Programa - 027.194.253-38 - SÉRGIO DANTAS DE OLIVEIRA JÚNIOR
Externo à Instituição - CARLOS EDUARDO DE ARAÚJO PADILHA - UFRN