title: Characterization of weld (Reseda luteola L.) and spurge flax (Daphne gnidium L.) by high-performance liquid chromatography-diode array detection-mass spectrometry in Arraiolos historical textiles.
abstract: The natural dyes, and dye sources, in two seventeenth century Arraiolos carpets from the National Museum of Machado de Castro were analysed by high-performance liquid chromatography with UV-vis diode array detection (HPLC-DAD) and HPLC-mass spectrometry (LC-MS). Weld (Reseda luteola L.), indigo and spurge flax (Daphne gnidium L.) were found to be the dye sources, in agreement with original dyeing recipes collected during the nineteenth century. In order to fully characterize the plant sources, LC-MS conditions were optimized with plant extracts and the chromatographic separation and mass detection were enhanced. Extraction of the dyes, in the Arraiolos carpet samples, was performed using mild conditions that avoid glycoside decomposition. For the blues a dimethylformamide solution proved to be efficient for indigotin recovery. For all the other colours, an improved mild extraction method (with oxalic acid, methanol, acetone and water) was used, enabling to obtain the full dye source fingerprint, namely the flavonoid glycosides in the yellow dyes.
authors.affiliation: Departamento de Conservação e Restauro, Faculdade de Ciências e Tecnologia, Universidade Nova de Lisboa, 2825 Monte da Caparica, Portugal.
authors.forename: Rita
authors.initials: R
authors.lastname: Marques
authors.forename: Micaela M
authors.initials: MM
authors.lastname: Sousa
authors.forename: Maria C
authors.initials: MC
authors.lastname: Oliveira
authors.forename: Maria J
authors.initials: MJ
authors.lastname: Melo
mesh_terms: D002851:Chromatography, High Pressure Liquid / Q000379:methods*; D002853:Chromatography, Liquid / Q000379:methods; D004396:Coloring Agents / Q000032:analysis* / Q000266:history; D032364:Daphne / Q000737:chemistry*; D005419:Flavonoids / Q000032:analysis; D005430:Floors and Floorcoverings / Q000266:history; D006027:Glycosides / Q000032:analysis; D049670:History, 17th Century; D013058:Mass Spectrometry / Q000379:methods*; D010936:Plant Extracts / Q000032:analysis; D031951:Resedaceae / Q000737:chemistry*; D013784:Textiles / Q000032:analysis / Q000266:history
chemical_list: D004396:Coloring Agents; D005419:Flavonoids; D006027:Glycosides; D010936:Plant Extracts