Maria Izabel Pereira

Publications (3)5.68 Total impact

• Article: Chemical structure and selected biological properties of a glucomannan from the lichenized fungus Heterodermia obscurata.

  Maria Izabel Pereira, Andrea Caroline Ruthes, Elaine R Carbonero, Rodrigo Marcon, Cristiane H Baggio, Cristina S Freitas, Adair Roberto S Santos, Sionara Eliasaro, Guilherme L Sassaki, Philip Albert J Gorin, Marcello Iacomini
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  ABSTRACT: Successive aqueous and alkaline extraction of the thallus of the lichenized fungus Heterodermia obscurata provided a highly branched glucomannan fraction (GM), whose chemical structure was determined. This was based on monosaccharide composition, methylation, partial acid hydrolysis, and NMR spectroscopic analysis. It consisted of a main chain of (1→6)-linked α-D-mannopyranosyl units, almost all being substituted at O-2 with α-D-glucopyranosyl, α-D-mannopyranosyl, and 4-O-substituted α-D-mannopyranosyl groups. Intra-peritoneal administration of this GM induced a marked and dose-dependent inhibition of acetic acid-induced visceral pain with an ID(50) of 0.6 (0.2-2.0) mg/kg and inhibition of 88±4%. It also reduced leukocyte migration by 58±4%, but did not alter plasmatic extravasation to the peritoneal cavity. The results suggest that the glucomannan from the H. obscurata might have potential for antinociceptive and anti-inflammatory utilization.
  Phytochemistry 10/2010; 71(17-18):2132-9. · 3.35 Impact Factor
• Article: A gel-forming beta-glucan isolated from the fruit bodies of the edible mushroom Pleurotus florida.

  Juliana C Santos-Neves, Maria Izabel Pereira, Elaine R Carbonero, Ana Helena P Gracher, Philip A J Gorin, Guilherme L Sassaki, Marcello Iacomini
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  ABSTRACT: Glucans of basidiomycetes are considered to be an important class of polysaccharides, as they can act as biological response modifiers. We now isolate a gel-forming, water-soluble beta-glucan, with a molecular mass of 1.2 x 10(6)g/mol (HPSEC), from the fruit bodies of the edible mushroom Pleurotus florida, via alkaline extraction, followed by fractionation by freeze-thawing. Structural assignments were carried out using mono- and bi-dimensional nuclear magnetic resonance spectroscopy, monosaccharide composition, methylation analyses, and a controlled Smith degradation. It was a branched beta-glucan, with a main chain of (1-->3)-linked-Glcp residues, substituted at O-6 by single-unit Glcp side chains, on average to every fourth residue of the backbone.
  Carbohydrate Research 07/2008; 343(9):1456-62. · 2.33 Impact Factor
• Article: A novel branched αβ-glucan isolated from the basidiocarps of the edible mushroom Pleurotus florida

  Juliana C. Santos-Neves, Maria Izabel Pereira, Elaine R. Carbonero, Ana Helena P. Gracher, Giovana Alquini, Philip A.J. Gorin, Guilherme L. Sassaki, Marcello Iacomini
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  ABSTRACT: As polysaccharides of the mushroom genus Pleurotus can act as biological response modifiers, we now describe the chemical characterization of a new water-soluble αβ-glucan from the fruiting bodies of the edible mushroom Pleurotus florida. It was obtained via successive aq. extraction, freeze-thawing, precipitation with Fehling solution, and dialysis through a membrane with Mr 1000 kDa cut-off. It was analyzed using NMR spectroscopy, HPSEC, monosaccharide composition, methylation analysis, and a controlled Smith degradation. It was a branched glucan (Mw 1.1 × 106 g/mol), with a main-chain of (1→3)-linked-α-d-Glcp residues, partially substituted at O-6 by single-unit β-d-Glcp, and a minor proportion by side-chains with 3-O-substituted β-d-Glcp groups.
  Carbohydrate Polymers.