Water extract from rhamnus berries (Rhamnus catharticits) is the base of Stil de grain lake (also called Buckthorn lake), an ancient dye used in textiles and in paintings. In this work, the main colored component of the lake was separated and its chemical structure determined by advanced NMR techniques. The results show that quercitrin, a glucoside derivative of quereetine (3,5,7,3',4'-pentahydroxy-flavone) is the principal colored form. This result does not agree with previous literature assignments. In this work a characterization of quercitrin in methanol and in water as a function of pH was carried out by absorption and emission UV-visible spectroscopy. (c) 2005 Elsevier Ltd. All rights reserved.
An NMR and UV-Visible spectroscopic study of the principal colored component of Stil de grain lake
ROMANI, Aldo;ZUCCACCIA, Cristiano;CLEMENTI, CATIA
2006
Abstract
Water extract from rhamnus berries (Rhamnus catharticits) is the base of Stil de grain lake (also called Buckthorn lake), an ancient dye used in textiles and in paintings. In this work, the main colored component of the lake was separated and its chemical structure determined by advanced NMR techniques. The results show that quercitrin, a glucoside derivative of quereetine (3,5,7,3',4'-pentahydroxy-flavone) is the principal colored form. This result does not agree with previous literature assignments. In this work a characterization of quercitrin in methanol and in water as a function of pH was carried out by absorption and emission UV-visible spectroscopy. (c) 2005 Elsevier Ltd. All rights reserved.I documenti in IRIS sono protetti da copyright e tutti i diritti sono riservati, salvo diversa indicazione.
