TITLE:
Structural Elucidation of Condensed Tannin from Picea mariana Bark
AUTHORS:
Papa Niokhor Diouf, Carmen Mihaela Tibirna, Martha-Estrella García-Pérez, Mariana Royer, Pascal Dubé, Tatjana Stevanovic
KEYWORDS:
Picea mariana Bark; Condensed Tannins; Proanthocyanidins; Polyphenols; Structural Characterization
JOURNAL NAME:
Journal of Biomaterials and Nanobiotechnology,
Vol.4 No.3A,
June
26,
2013
ABSTRACT: The aim of this work was to determine
the structural characteristics of the condensed tannins isolated from the
aqueous extract of black spruce (Picea
mariana Mill) bark. This is the first report on the structural
characterization of condensed tannins from black spruce bark. The condensed
tannins from the hot water extract prepared from Picea mariana bark were isolated by column chromatography on
Sephadex LH-20 media. In this study, UV-visible and 13C-NMR spectroscopic techniques, along with pyrolysis-gas
chromatography/mass spectrometry (Py-GC/MS) and liquid chromatogramphy analyses were applied to determine the
structural characteristics of black spruce bark tannins. We have confirmed for
the first time the presence of methoxylated B-rings in the flavanol units of
condensed tannins from black spruce bark, which could be regarded as further
contribution to the chemotaxonomy of the genus Picea. The methoxylation of Norway spruce bark condensed tannins have been demonstrated previously.