Banca de QUALIFICAÇÃO: MARILIA MEDEIROS FERNANDES DE NEGREIROS

Uma banca de QUALIFICAÇÃO de DOUTORADO foi cadastrada pelo programa.
DISCENTE : MARILIA MEDEIROS FERNANDES DE NEGREIROS
DATA : 16/09/2019
HORA: 08:00
LOCAL: Sala Carl Von Dietrich
TÍTULO:

Chemical modifications of polysaccharides from the Lobophora variegata and Ddictyota mertensii seaweeds potencialize their biological activities.

PALAVRAS-CHAVES:

brown seaweed; antioixdant; immunomodulator/ anti-bacterial

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 algae and have several biological activities described. Objective: The objective of this work was to extract laminarine from Lobophora variegata and D. mertensii kelp and to evaluate their biological activities. In addition, these polysaccharides were modified by sulfation, dielectric barrier discharge (DBD), galification and used for nanoparticle synthesis. Modifications were evaluated for biological activities. Materials and Methods: L. variegata and D. mertensii algae 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, fucana nanoparticle showed better biological activities than native fucana. Overall, the data showed that gallification improved chemical modification in Lobophora variegata laminarins and fucan nanoparticles enhanced the biological activities of fucans.

MEMBROS DA BANCA:
Externa à Instituição - JAILMA ALMEIDA DE LIMA - CRI
Presidente - 046.477.204-46 - LEANDRO SILVA COSTA - IFRN
Externo à Instituição - RANIERE FAGUNDES DE MELO SILVEIRA