Banca de DEFESA: MARILIA MEDEIROS FERNANDES DE NEGREIROS

Uma banca de DEFESA de DOUTORADO foi cadastrada pelo programa.
DISCENTE : MARILIA MEDEIROS FERNANDES DE NEGREIROS
DATA : 26/09/2019
HORA: 14:00
LOCAL: Sala Carl Peter von Dietrich - Departamento de Bioquímica
TÍTULO:

Chemical modifications of polysaccharides of the algae Lobophora variegata and Dictyota mertensii enhancing their pharmacological activities.

PALAVRAS-CHAVES:

Laminarin, Fucan, Brown seaweed, Cold plasma.

PÁGINAS: 193
GRANDE ÁREA: Ciências Biológicas
ÁREA: Bioquímica
SUBÁREA: Química de Macromoléculas
RESUMO:

Laminarines are (1,3) -β-glucans and fucans are sulfated polysaccharides consisting of sulfated L-fucose, both of which are synthesized by brown seaweeds and have several biological activities described. Thus, this work aimed to extract laminarine from the algae Lobophora variegata and fucans from the Dictyota mertensii and evaluate their biological activities. In addition, these polysaccharides were modified by sulfation, dielectric barrier discharge (DBD), galification and used for nanoparticle synthesis and this modifications were evaluated for biological activities. The seaweed L. variegata and D. mertensii were collected at Pirangi beach, Natal, RN, washed and submitted to proteolysis for 18 h. Then the supernatant was precipitated with increasing volumes of acetone and the fraction was named: F0.3; F0.5; F0.8; F1.0 F1.5 and F2.0 according to the volume required for polysaccharide precipitation. Subsequently, fractions F0.8 and F1.0 were used for laminarin purification using the molecular weight separation system. The modified laminarins were modified using DBD, sulfation and galification. And the fucanas were used for nanoparticle synthesis. The 12.4 kDa laminarine presented low protein contamination (0.3%) and phenolic compounds (0.1%). The modification that most enhanced the biological activities of laminarins was galification. In addition, fucan nanoparticle showed better biological activities than native fucan. In general, it was observed that the galification was to improve chemical modification in Lobophora variegata laminarins and the fucan nanoparticles enhanced the biological activities of fucans from Dictyota mertensii.

MEMBROS DA BANCA:
Externa à Instituição - CINTHIA BEATRICE DA SILVA TELLES - IFRN
Presidente - 2195251 - HUGO ALEXANDRE DE OLIVEIRA ROCHA
Interno - 046.477.204-46 - LEANDRO SILVA COSTA - IFRN
Externa à Instituição - MARIANA SANTANA SANTOS PEREIRA DA COSTA - IFRN
Externa ao Programa - 2477216 - NAISANDRA BEZERRA DA SILVA FARIAS
Externo à Instituição - ÉDER GALINARI FERREIRA - UFRPE