Isolation and structure elucidation of tannins

  title={Isolation and structure elucidation of tannins},
  author={Gen-ichiro Nonaka},
  journal={Pure and Applied Chemistry},
  pages={357 - 360}
  • G. Nonaka
  • Published 1989
  • Chemistry
  • Pure and Applied Chemistry
Chemical examinations show that a new class of tannins designated as 'complex tannin' occurs widely in the plants containing both condensed and hydrolyzable t annins. The complex tannins are shown to contain in the molecules a hydrolyzable t annin moiety connected through a carbon-carbon linkage to flavan-3-01 (flavano-ellagit annin) , procyanidin (procyanidino- ellagitannin) and flavonoid glucoside (flavono-ellagit annin) moieties. Some of the significant findings obtained in the fields of… 
Tannin structural elucidation and quantitative ³¹P NMR analysis. 1. Model compounds.
The development of a new analytical method employing an in situ labeling of all labile H groups (aliphatic OH, phenolic OH, and carboxylic acids) with a phosphorus reagent allowed the unprecedented quantitative and qualitative structural characterization of hydrolyzable tannins, proanthocyanidins, and catechin tannin model compounds.
Pharmacologically active tannins isolated from medicinal plants.
Noticeable biological and pharmacological activities (inhibition of carcinogenesis, host-mediated antitumor activity, antiviral activity, and inhibition of active oxygen, such as inhibition of lipid peroxidation and lipoxygenase, xanthine oxidase, and monoamine oxidase) have been found for several polyphenolic compounds.
Study on the composition and structure of commercial chestnut tanning agent.
Two chestnut tannins, vescalagin and castalagin, have been isolated using chromatography on Sephadex LH-20 and cellulose andStructural features of these compounds provide a better understanding of the mode of action of complex commercial chestnuts tannin extracts.
Tannin structural elucidation and quantitative ³¹P NMR analysis. 2. Hydrolyzable tannins and proanthocyanidins.
An unprecedented analytical method that allows simultaneous structural and quantitative characterization of all functional groups present in tannins is reported, with significant implications for the fields of food and feed analyses, tannery, and the development of natural polyphenolics containing products.
Tannin analysis of chestnut bark samples (Castanea sativa Mill.) by HPLC-DAD-MS.
The HPLC-DAD/ESI-MS method provided information regarding the composition and quality of chestnut bark samples, which is required since these samples are commercialised due to their biochemical properties as ingredients of food supplements.
Analysis of hydrolysable tannins
This review deals with the main issues relating to the analysis of hydrolysable tannins (HTs). It covers briefly their distribution in the plant kingdom and describes their main structural features.
Isolation and Identification of Inhibitory Compound from Crataegi Fructus on ${\alpha}-amylase$ and ${\alpha}-glucosidase$
The objective of this research was to evaluate the inhibitory activities of phenolic compounds isolated from Crataegi Fructus on and . The content of total phenolic compounds of water extract from
The quantification of condensed tannins in African savanna tree species
Condensed tannins purified from the plant under investigation be used as standard since it will closely represent the CT structure and presumably chemical reactivity in the acid-butanol assay.
A new sesquiterpene lactone glycoside and a new quinic acid methyl ester from Patrinia villosa
A new sesquiterpene lactone glycoside and a new quinic acid methyl ester were isolated from Patrinia villosa and their structures were established using 1D/2D-NMR spectroscopy, mass spectrometry, and comparing with spectroscopic data reported in the literature.
Novel metabolites of hexahydroxydiphenic acid esters (ellagitannins) from Carpinus japonica
The unique hydrated biscyclohexenetrione structures (1)–(4) of carpinins A–D, the metabolites of hexahydroxydiphenic acid esters (ellagitannins) isolated from the leaves of Carpinus japonica, are


G.Nonaka and I .N ish ioka
  • 1987