PT  - JOURNAL ARTICLE
AU  - Nicolas Vivas
AU  - Isabelle Pianet
AU  - Guy  Bourgeois
AU  - Christiane Vitry
AU  - Christian  Servens
AU  - Yves Glories
TI  - Characterization of Heartwood Lignin Fractions from <em>Quercus robur</em> L. and <em>Quercus petraea</em> (Matt) Liebl., the Main Oak Species Used for Barrel Making
AID  - 10.5344/ajev.1998.49.1.49
DP  - 1998 Jan 01
TA  - American Journal of Enology and Viticulture
PG  - 49--55
VI  - 49
IP  - 1
4099  - http://www.ajevonline.org/content/49/1/49.short
4100  - http://www.ajevonline.org/content/49/1/49.full
SO  - Am J Enol Vitic.1998 Jan 01; 49
AB  - Various methods were used to characterize three kinds of lignin fractions from the heartwood of Quercus robur and Q. petraea. UV analysis and determination of the mean molecular mass showed that the first fraction, soluble in a hydroalcoholic medium and extractable with dichloromethane, is a mixture of oligomer lignins with a mass below 800 Da, highly enriched with free phenol aldehyde and lyoniresinol. The LE and LD fractions, extractable with ethanol and dioxane, respectively, are relatively pure lignins. LE and LD thioacidolysis products, and LE sine contains ellagic acid. IR and GC-MS analysis of their thioacidolysis products enabled us to demonstrate the heterogeneity of these two lignins. LE is characterized by an S/G close to 1, while LD has an S/G ratio between 1.41 and 1.67, characteristic of lignins rich in syringyl units.