Banca de DEFESA: MARCELA DE CASTRO NOGUEIRA DINIZ PONTES
Uma banca de DEFESA de DOUTORADO foi cadastrada pelo programa.DISCENTE : MARCELA DE CASTRO NOGUEIRA DINIZ PONTES
DATA : 26/07/2019
HORA: 14:00
LOCAL: auditório do Química III
TÍTULO:
SECONDARY METABOLITES OF Agelas SPONGES FROM NORTHEAST COAST OF BRAZIL
PALAVRAS-CHAVES:
Agelas, Bromopyrrole, Antibacterial, Alkaloid, Oroidin
PÁGINAS: 141
GRANDE ÁREA: Ciências Exatas e da Terra
ÁREA: Química
SUBÁREA: Química Orgânica
ESPECIALIDADE: Química dos Produtos Naturais
RESUMO:
The genus of marine sponges Agelas is source of brominated pyrrole and imidazole alkaloids, terpene derivatives and sterols, many of them with amino acid moieties. Its metabolites are associated with biological activities useful to human being, such as antitumor, antihistaminic, antibacterial, antifungal, cytotoxic, calcium channel modulator and antiserotoninergic, among others. In this work, two extracts from Agelas collected on brazilian northeast coast were investigated. First, semi crude fractions from extract of Agelas dispar were tested in microbiological assay and demonstrated antibacterial action against eight bacterial strains, such as Staphylococcus aureus, Staphylococcus. epidermidis, Staphylococcus hominis, Enterococcus faecalis, Enterococcus faecium, Pseudomonas aeruginosa, Escherichia Coli and Salmonella enteriditis. The fraction derived from ethyl acetate showed higher antibacterial action, with MIC = 39.06 μg/ ml. The ethanol extract from another Agelas sponge and the antibacterial fractions from A. dispar were analyzed in HPLC-MS, and were identified the metabolites longamide B, methyl ester of longamide B, mukanadine A and E, clathramide A, oroidine, 4,5-dibromo-2-carboxamide, 4,5-dibromo-2-carboxylic acid, hanishine, 9,10 di-hydro-keramadine, dispacamide A and methyl-hymenidine through positive mode. Also were identified, by HPLC-MS negative mode, the compounds agesamide, dispacamide D, mauritamide D. The GC-MS analysis permitted identification of sterols and ester from fatty acids such as penta, hexa, hepta and octadecanoic, besides nonadecen, docosanol, tetracosanol, pentacosanol and heptacosanol, behenic acid, squalene and 2,4-terc-butyl-phenol, all obtained from the fractioning of lipid extracts. The substance 4-bromopyrrole-2-carboxamide were isolated. Fractionation and identification of the metabolites was achieved through classical chromatographic techniques, GC-MS, HPLC-MS and 1H and 13C uni and bidimensional NMR.
MEMBROS DA BANCA:
Interno - 1803692 - FABRICIO GAVA MENEZES
Externo ao Programa - 2276354 - LEANDRO DE SANTIS FERREIRA
Externa à Instituição - MARIA DE FÁTIMA VANDERLEI DE SOUZA - UFPB
Presidente - 1569526 - RENATA MENDONÇA ARAUJO
Externa à Instituição - YANNA CAROLINA FERREIRA TELES - UFPB