Pagoda tree (Styphnolobium japonicum) LC

pagoda tree flowers and buds/ photo by X. Zhang

pagoda tree/Photo by X. Zhang

Description

The Pagoda tree, Styphnolobium japonicum(=Sophora japonica), is medium sized tree native to Japan, China and India that has been used to produce a yellow dye.

Historical Importance

Pagoda tree buds, which have to be roasted or steamed immediately after collection, have been recorded in ancient Chinese books as a dye source for yellow for thousands of years. The dyeing process, using pagoda tree buds has been recorded in several ancient Chinese books, including Tian Gong Kai Wu 《天工开物》(Chinese Technology in the Seventeenth Century), Duo Neng Bi Shi 《多能鄙事》(Many Abilities in Humble Activities), Bu Jing 《布經》 and Zhiranju buce 《織染局簿冊》.

Pagoda tree bud dyes have been reported to be the dyeing source of some historical textiles dated back to the Qing Dynasty in China [2,3]. Pagoda tree buds have also been identified in 19th century suzanis collected in Uzbekistan [4].

Examples:

V&A V&A T.184-1948

MAA КП1276/3

V&A T. 43-1952

PEM E80968

Synonyms and Related Terms

Japanese pagoda tree (Sophora japonica; Styphnolobium japonicum); Chinese scholar tree, waifa; enjo エンジュ(Jap.)槐(Chinese).

Roasted Pagoda tree buds. Photo by X. Zhang

Summary of results

The major components of unheated pagoda tree buds 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 quercetin. Heating freshly harvested buds inactivates the enzyme, with the result that dyes prepared from such buds will mainly contain rutin, with very little quercetin. Historical textiles dyed with pagoda tree buds contain mainly rutin.

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.

Chromatograms

HPLC-DAD of pagoda tree bud extract. The sample (~0.1g), from Tanakanao, Japan, was extracted with 1 mL of methanol:H2O (v:v=1:1). Then the upper 30 μL of solution was removed for HPLC-DAD-MS analysis (20 μL was injected).

Absorbance at 350nm (mAU)

Results

compounds identified

Identified compounds

HPLC-DAD and MS data of a Qing dynasty textile sample. by X. Zhang

Rutin UV-Vis

Quercetin UV-Vis

Isorhamnetin UV-Vis

Kaempferol UV-Vis

Compound	RT (min.)	MW	UV/vis	Other
rutin	27.0	610	278,352	Comments here
quercetin	34.6	302	280,395,370
kaempferol	39.0	286	280,395,368
isorhamnetin	39.0	316	280,395,368

References

[1] X. Zhang, and , R. Laursen, 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).

[2] X. Zhang, Corrigan, K., MacLaren, B., , M., and , R. A. Laursen, Characterization of Yellow Dyes in Nineteenth Century Chinese Textiles. Studies in Conservation 52, 211-220 (2007).

[3] J. Han, The Historical and chemical investigation of dyes in high status Chinese costume and textiles of the Ming and Qing Dynasties (1368-1911), PhD thesis, University of Glasgow, February 2016.

[4] X. Zhang, R. Laursen, and S. Osipova, Analysis of dyes in some 19th-century Uzbek suzanis. Dyes in History and Archaeology (in press).