Elucidação estrutural de heterogalactanas parcialmente metiladas obtidas de Grifola frondosa (“Maitake”) e Pleurotus ostreatus (“Shimeji”)
Carregando...
Data
2013-07-18
Autores
Título da Revista
ISSN da Revista
Título de Volume
Editor
Universidade Federal de Goiás
Resumo
Partially methylated heterogalactans were isolated from the fruiting bodies of
the medicinal mushroom Pleurotus ostreatus (mannogalactan) and Grifola
frondosa (mannofucogalactan), via successive cold aqueous extraction,
followed by fractionation through freeze-thawing, precipitation with Fehling
solution of soluble material, and dialysis using membranes with different
exclusion limits (MWCO 50, 100, and 500 kDa). Their chemical structures were
established based on monosaccharide composition, methylation analysis and
NMR studies. The mannogalactan (Mw = 50.7 x 103 g.mol-1) had a main chain of
(1→6)-linked α-D-galactopyranosyl and 3-O-methyl-α-D-galactopyranosyl units,
both of which are partially substituted at O-2 by -D-mannopyranosyl nonreducing
ends.The other was a mannofucogalactan (Mw = 15.9 x 103 g.mol-1),
which had a similar main-chain, being a part of the galactopyranosyl units
substituted at O-2 mainly by 3-O-α-D-mannopyranosyl-α-L-fucopyranosyl groups
and in a minor proportion with α-L-Fucp single-unit side chains. Recently, the
heterogalactans are also recognized for their relevant biological activities, such
as antitumor, immunomodulatory, anti-inflammatory and antinociceptive effects.
Thus, the heterogalactans obtained from G.frondosa and P. ostreatus could
present itself as a good candidate to be evaluated for its biological potential.
Descrição
Palavras-chave
Cogumelos medicinais, Grifola frondosa, Pleurotus ostreatus, Heterogalactana, Estrutura química, Medicinal mushrooms, Grifola frondosa, Pleurotus ostreatus;, Heterogalactans, Chemical structure
Citação
OLIVEIRA, Gracy Kelly Faria. Elucidação estrutural de heterogalactanas parcialmente metiladas obtidas de Grifola frondosa (“Maitake”) e Pleurotus ostreatus (“Shimeji”). 2013. 75 f. Dissertação (Mestrado em Química) - Universidade Federal de Goiás, Catalão, 2013.