Comparative sorption isotherms for colorants present in Dyers’ madder (Rubia tinctorum L.) provide new insights into historical dyeing

Abstract

Dyers madder (Rubia tinctorum L.) has been famously used throughout history as a source of red dye. The sorption onto mordanted wool of the major colorant components of R. tinctorum, alizarin and the glycosides ruberythric acid and lucidin primeveroside, is studied herein. Sorption of a purified 1:1 mixture of ruberythric acid:lucidin primeveroside most closely followed a Temkin isotherm (R 2 0.925), whereas alizarin followed a Freundlich isotherm (R 2 0.940). These results were compared with HPLC chromatograms of English, Turkish and Iranian varieties of R. tinctorum before and after dyeing, where it was observed that the glycosides are shown to have the highest uptake onto wool. The higher sorption energy of the purified 1:1 ruberythric acid: lucidin primeveroside mixture (-11.4 kJ mol À1 ) compared with alizarin (-5.8 kJ mol À1 ) is in agreement with the HPLC results, indicating that the ruberythric acid/lucidin primeveroside mixture has a substantially higher affinity for wool compared with alizarin. Not only do the glycosides show higher affinity for the wool, but greater interactions between adsorbed species suggest a more extensive aggregation of dye on the surface of the wool. These observations are in contrast with much of the literature and bring into question previous conclusions that alizarin was the main dyeing species throughout history. Coloration Technology Society of Dyers and ColouristsO-Primeveroside, O-(6-O-b-D-xylopyranosyl-D-glucopyranosyl). ++ indicates major compound in planta, + significant amount, tr. very low or trace amount.Ford et al. Sorption isotherms in Rubia tinctorum

Comparison of madder (Rubia tinctorum L.) and weld (Reseda luteola L.) total extracts and their individual dye compounds with regard to their dyeing behaviour, colour, and stability towards light

“…Looking at weld compounds, the glucoside ldg has poor dye uptake, probably caused by a diminished bonding ability with the mordant. The poor uptake for the glycosides does not match results from Ford et al [21], wherein it was observed that ruberythric acid has preferential sorption properties on wool over the aglycone alizarin. In the case of glucoside ldg, one of two vicinal hydroxyl groups is attached to glucose and no longer available for bonding.…”

“…The poor uptake for the glycosides does not match results from Ford et al . , wherein it was observed that ruberythric acid has preferential sorption properties on wool over the aglycone alizarin. Differences in experimental set‐up (dyeing time, concentration, liquor‐fibre ratio) may be a reason for this.…”

“…In contrast, the scientific expertise on natural dyes is still growing. Ford et al [21] reported the sorption behaviour of pure alizarin and a mixture of lucidin primeveroside and ruberythric acid on wool. Sakata and Katayama reported the results of dyeing silk with three individual anthraquinones from madder [18].…”

“…Ford et al . reported the sorption behaviour of pure alizarin and a mixture of lucidin primeveroside and ruberythric acid on wool. It is our belief that detailed comprehension of the colorimetric behaviour of individual dye compounds leads to more insight into the behaviour of the total plant extract.…”

Simple crystallization approach for enhancing function of plant-based madder dye and performance of dyed fabric

“…In comparison between natural dyes and synthetic dyes, natural dyes are non-allergic, non-toxic, biodegradable, and do not cause environmental pollution [1, 2, 3, 4]. The use of madder (red dye) has been flourishing for centuries and ranging from Europe, Asia to Africa [5, 6, 7]. The dried roots of this plant are used as a component in herbal medicines for its anticancer, antifungal, anti-inflammatory and antioxidant activities.…”