Banca de QUALIFICAÇÃO: KEYLLA DAYANNE COELHO

Uma banca de QUALIFICAÇÃO de DOUTORADO foi cadastrada pelo programa.
STUDENT : KEYLLA DAYANNE COELHO
DATE: 15/06/2022
TIME: 14:30
LOCAL: DEFESA REMOTA - https://meet.google.com/wkk-cwkf-tnw
TITLE:

ANTIOXIDANT ACTIVITY OF FUCOIDAN MODIFIED BY THE REDOX METHOD WITH GALLIC ACID

KEY WORDS:

Keywords: sulfated polysaccharides, oxidative damage and antioxidant activity.

PAGES: 22
BIG AREA: Ciências Biológicas
AREA: Bioquímica
SUMMARY:

The antioxidant properties of fucoidans are important for the treatment of various diseases. Here, we modified a fucoidan (FucA) from Spatoglossum schröederi by the redox method using Gallic acid (GA) in order to potentiate the protective capacity of osteoblastic cells against oxidative stress. The chemical characteristics of FucA and FucA-GA (Fucan A conjugated with GA) were verified and the determination of the process of conjugation of the polysaccharide with the GA was analyzed by the quantification of the phenolic compounds. The approximately fourfold increase in phenolic compounds in the FucA-GA solution demonstrates the efficiency of the method used. Antioxidant activity was measured by reducing power, ability to chelate iron and copper, total antioxidant capacity and analysis of cellular protection in an oxidative medium. A significant difference was found between the 0.25µg samples of FucA and FucA-GA for copper chelation. It is noteworthy that the 0.25 µg FucA-GA sample presented a higher copper chelation than that observed with FucA 2 µg. The statistical analysis performed demonstrates significant differences in the antioxidant capacity of FucA-GA when compared to FucA. FucA-GA showed a protective capacity in vivo and a lower rate of cellular apoptosis in Zebrafishing embryos. The in vivo and in vitro results suggest a high capacity of the polysaccharides modified by GA to reduce the damage caused by free radicals.

BANKING MEMBERS:
Presidente - 2195251 - HUGO ALEXANDRE DE OLIVEIRA ROCHA
Externa à Instituição - MARÍLIA MEDEIROS FERNANDES DE NEGREIROS - IFRR
Externa à Instituição - MICHELLE DE MEDEIROS AIRES - UFRN