Results 151 to 160 of about 2,967 (197)

Biosynthesis and subcellular distribution of hydrolyzable tannins

Phytochemistry, 2001
Pathways to complex gallotannins have been elucidated by enzyme studies, indicating that beta-glucogallin is required as principal acyl donor. Evidence for the in vitro oxidation of pentagalloylglucose, the pivotal metabolite in this sequence, to ellagitannins, is presented. Immunohistochemical studies with antibodies raised against pentagalloylglucose
P, Grundhöfer, R, Niemetz, G, Schilling, G G, Gross   +3 more
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Chemical Studies of Proanthocyanidins and Hydrolyzable Tannins

Antioxidants & Redox Signaling, 2001
We investigated a number of natural polyphenols representing flavan-3-ols, gallotannins, and ellagitannins with regard to their antioxidant potential. For this purpose we used pulse radiolysis to determine scavenging rate constants with hydroxyl radicals and decay rates of the respective aroxyl radicals and EPR spectroscopy to identify the radicals ...
W, Bors, L Y, Foo, N, Hertkorn, C, Michel, K, Stettmaier   +4 more
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Hydrolyzable Tannins and Related Polyphenols

1995
Recent advances in isolation and structure elucidation of several hundred of new polyphenolic compounds of the tannin class using new techniques (1) have altered the definition of a tannin, at least that of a hydrolyzable tannin. Thus the term tannin now includes all polyphenolic compounds of defined chemical structure as well as the whole group of ...
T, Okuda, T, Yoshida, T, Hatano
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Hydrolyzable tannin analysis in food

Food Chemistry, 2012
The discovery of plant polyphenols in food is perhaps one of the biggest breakthroughs in modern food science. Plant polyphenols are known for their role in food quality and safety, since they contribute significantly to taste, flavour, colour, stability etc., while they are increasingly recognised as important factors in long-term health, contributing
openaire   +3 more sources

Oligomeric hydrolyzable tannins from Monochaetum multiflorum

Phytochemistry, 2004
Four hydrolyzable tannins, nobotanins Q, R, S, and T, were isolated from the aqueous acetone extract of the dried leaves of Monochaetum multiflorum (Melastomataceae), a plant indigenous to Colombia. Their dimeric and tetrameric structures were elucidated by spectral and chemical methods.
José H, Isaza, Hideyuki, Ito, Takashi, Yoshida   +2 more
openaire   +2 more sources

Lignin-Hydrolyzable Tannin Interactions in Wood

Journal of Agricultural and Food Chemistry, 1997
A series of investigations were carried out to ascertain the relationship between lignin and hydrolyzable tannins in white oak (Quercus alba) and American chestnut (Castanea dentata) milled wood lignins as well as synthetic co-DHPs. Acidolysis and chromatographic analysis of chestnut and white oak milled wood lignins revealed the presence of ellagic ...
Richard F. Helm, Thilini D. Ranatunga, Mudit Chandra   +2 more
openaire   +1 more source

Hydrolyzed Tannins from Geranium pusillum

Chemistry of Natural Compounds, 2003
The polyphenolic compound 1-O-galloyl-3,6-hexahydroxybiphenyl-D-galactopyranoside (pusilagin) was isolated from the aerial part. The tannin structure was established using acid hydrolysis and IR, PMR, and 13C NMR spectral methods.
K. B. Kobakhidze, M. D. Alaniya
openaire   +1 more source

Cytotoxic Hydrolyzable Tannins from Balanophora japonica

Journal of Natural Products, 2008
Four hydrolyzable tannins named balanophotannins D-G ( 1- 4) were isolated from the aerial parts of the parasitic plant Balanophora japonica. Their structures were characterized on the basis of spectroscopic and chemical evidence. Balanophotannins D-G contain an oxidized hexahydroxydiphenoyl (HHDP) group. The absolute configurations of balanophotannins
Zhi-Hong, Jiang, Xiao-Yun, Wen, Takashi, Tanaka, Shao-Yu, Wu, Zhongqiu, Liu, Hiromi, Iwata, Yoko, Hirose, Shuguang, Wu, Isao, Kouno   +8 more
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Protein-tannins binding mode in hydrolyzable tannins-induced protein aggregation

Food Chemistry
Because the interaction between proteins and tannins is complex, the mode of binding has not yet been elucidated. Elucidating this interaction has been considered impossible to accomplish, especially in water, in which proteins retain their three-dimensional (3D) structure. In this study, a combination of molecular dynamics (MD) simulations of multiple
Mana, Yoshimura, Yoshiki, Sugahara, Kana, Nagase, Miho, Kobayashi, Yuji O, Kamatari, Kosei, Yamauchi   +5 more
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Antitumor-promoting activities of hydrolyzable tannins in mouse skin

Carcinogenesis, 1992
Ellagic acid and gallic acid and its derivatives, applied topically to female CF-1 mice 20 min before each 12-O-tetradecanoylphorbol-13-acetate (TPA) treatment inhibit the inductions of epidermal ornithine decarboxylase activity, hydroperoxide production and DNA synthesis caused by this potent tumor promoter in relation with their abilities to inhibit ...
H U, Gali, E M, Perchellet, D S, Klish, J M, Johnson, J P, Perchellet   +4 more
openaire   +2 more sources