Pagoda tree buds LC
The pagoda tree is medium sized tree, Styphnolobium japonicum, native to Japan, China and India that has been used to produce a yellow-green dye, waifa green, using an alum mordant with the flower extract then drying the cloth in the sun.
Synonyms and Related Terms
Japanese pagoda tree (Sophora japonica; Styphnolobium japonicum); waifa; enjo (Jap.)
Summary of results
The major components of the plant are three flavonols and their glycosides, as shown in the chromatogram. The major glycoside is rutin. The buds contain an enzyme that converts rutin to its aglycone quercitin. Heating freshly harvested buds inactivates the enzyme, with the result that dyes prepared from such buds will mainly contain rutin, with very little quercitin. Historical textile dyed with pagoda buds often mainly contain rutin.
Pagoda tree buds sample (~0.1g) from Tanakano, Japan was extracted with 1 mL methanol:H2O (v:v=1:1). Then the upper 30 μl of solution was removed for HPLC-DAD-MS analysis (20 μl was injected).
Analytical instrumentation and procedures
HPLC-DAD-MS analysis was performed with an Agilent 1100 liquid chromatography system consisting of an automatic injector, a gradient pump, a HP series 1100 DAD, and an Agilent series 1100 VL on-line atmospheric pressure ionization electrospray ionization mass spectrometer. Separations were done on a Vydac 214TP52 analytical column (2.1 mm diameterX250 mm; 5-ím particle size). The column was eluted at a flow rate of 0.2 mL/min with a tertiary gradient of water (A),acetonitrile (B), and 1% (v/v) aqueous formic acid (C) with the following elution program: 0 min, 90% A, 5% B, 5% C; 0-55 min, a linear gradient to 35% A, 60% B, 5% C; 55-60 min, a linear gradient elution to 15% A, 80% B, 5% C; 60-62 min, isocratic elution at 15% A, 80% B, 5% C; 62-70 min gradient elution to 90% A, 5% B, 5% C; and reequilibration with the latter solvent for 15 min. The mass spectrometer was run both in the negative and positive ion mode.
- Zhang, X., and , R. A., Development of Mild Extraction Methods for the Analysis of Natural Dyes in Textiles of Historical Interest Using LC-Diode Array Detector-MS. Analytical Chemistry 77, 2022-2025 (2005).
- Zhang, X., Corrigan, K., MacLaren, B., , M., and , R. A., Characterization of Yellow Dyes in Nineteenth Century Chinese Textiles. Studies in Conservation 52, 211-220 (2007).