Results 201 to 210 of about 9,883 (233)

Monomeric and dimeric hydrolysable tannins of Tamarix nilotica

Phytochemistry, 2009
An ellagitannin monomer, nilotinin M1 (1), and three dimers, nilotinins D1 (2), D2 (3), and D3 (4), were isolated from leaves of Tamarix nilotica (Ehrenb.) Bunge. Structures were elucidated based on analysis of spectroscopic data and chemical correlations with known compounds.
Mohamed A A, Orabi, Shoko, Taniguchi, Tsutomu, Hatano   +2 more
openaire   +2 more sources

Circular dichroism of hydrolysable tannins-II dehydroellagitannins

Tetrahedron Letters, 1982
Abstract The CD spectra of dehydroellagitannins and related compounds have empirically shown that the absolute configuration at C-1′ of the dehydrohexahydroxydiphenoyl group can be determined by the Cotton effect around 200 nm.
Takuo Okuda, Takashi Yoshida, Tsutomo Hatano, Toshitaka Koga†, Namiko Toh†, Kaoru Kuriyama††   +5 more
openaire   +1 more source

Flow injection system for hydrolysable tannin determination

Microchemical Journal, 2006
Abstract A flow injection system was proposed to evaluate the transient product of a colorimetric reaction between hydrolysable tannin and potassium iodate (KIO 3 ) solution. The system optimization was accomplished by using statistical methods based on experimental design.
Carla M. Bossu, Edilene C. Ferreira, Fernanda S. Chaves, Eveline A. Menezes, Ana Rita A. Nogueira   +4 more
openaire   +1 more source

Hydrolysable tannins and proanthocyanidins from green tea

Phytochemistry, 1984
Abstract Two hydrolysable tannins were isolated from green tea, and their structures were characterized by chemical and spectral means as 1,4,6-tri- O -galloyl-β- d -glucose and 1- O -galloyl-4,6-(−)-hexahydroxydiphenoyl-β- d -glucose. In addition, a new proanthocyanidin gallate was isolated, together with the known procyanidins B-2, B-4 and C-1 ...
Gen-Ichiro Nonaka, Ryo Sakai, Itsuo Nishioka   +2 more
openaire   +1 more source

Methylation, acetylation and gel permeation of hydrolysable tannins

Journal of Chromatography A, 1994
Abstract Different derivatization methods for hydrolysable tannins were compared and assessed for calibration of gel permeation systems. Methylation of ellagitannins such as vescalagin or castalagin with either diazomethane or dimethyl sulphate yields small amounts of the expected permethylated products together with several by-products resulting ...
Carole Viriot, Augustin Scalbert, Catherine L.M. Hervé du Penhoat, Christian Rolando, Michel Moutounet   +4 more
openaire   +3 more sources

Condensed and Hydrolysable Tannins as Antioxidants Influencing the Health

Mini-Reviews in Medicinal Chemistry, 2008
Natural polyphenols are a wide class of secondary plant metabolites and represent an abundant antioxidant component of human diet. An important, but often neglected group of natural polyphenols, are tannins. This review offers a general description of chemistry of both hydrolysable and condensed tannins (proanthocyanidins), the mechanisms of their ...
Vit, Koleckar, Katerina, Kubikova, Zuzana, Rehakova, Kamil, Kuca, Daniel, Jun, Ludek, Jahodar, Lubomir, Opletal   +6 more
openaire   +2 more sources

Differential scanning calorimetry of hydrolysed mangrove tannin

Polymer International, 2000
Mangrove-bark-tannin adhesives are potential substitutes for phenol–formaldehyde (PF) wood-bonding adhesives which are derived from petroleum, a finite natural resource. However, mangrove-bark-tannin adhesive exhibits poor adhesive properties, including brittleness, poor wet strength, and poor wood penetration.
S Sowunmi, R?O Ebewele, O Peters, A?H Conner   +3 more
openaire   +1 more source

Hydrolysable tannins and related compounds from Castanea mollissima

Phytochemistry, 1988
Abstract A chemical examination of the leaves of Castanea mollissima has led to the characterization of four new polyphenolic compounds, castamollissin, isochesnatin, isochestanin and castanin. In addition, the occurrence of 20 known hydrolysable tannins and related compounds was demonstrated.
Huiming Feng, Gen-Ichiro Nonaka, Itsuo Nishioka   +2 more
openaire   +1 more source

Two macrocyclic hydrolysable tannin dimers from Eugenia uniflora

Phytochemistry, 1997
Abstract Eugeniflorins D1 and D2 new hydrolysable tannin dimers, were isolated, together with four known polyphenols, from Eugenia uniflora leaves. Their macrocyclic structures were elucidated from spectral and chemical evidence.
null Mei-Hsien Lee, Saori Nishimoto, null Ling-Ling Yang, null Kun-Ying Yen, Tsutomu Hatano, Takashi Yoshida, Takuo Okuda   +6 more
openaire   +1 more source

Analysis of condensed and hydrolysable tannins from commercial plant extracts

Journal of Pharmaceutical and Biomedical Analysis, 2006
High performance liquid chromatography (HPLC)/DAD and MS qualitative and quantitative analyses of polyphenols, hydrolysable and condensed tannins from Pinus maritima L. and tannic acid (TA) extracts were performed using normal and reverse phase. Normal-phase HPLC was more suitable for pine bark (PBE) and tannic acid extracts analysis.
ROMANI, ANNALISA, IERI, FRANCESCA, B. Turchetti, MULINACCI, NADIA, VINCIERI, FRANCO FRANCESCO, P. Buzzini   +5 more
openaire   +3 more sources