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Dye

References for the investigation of mild extraction techniques

Traditional extraction methods of paint samples or textile samples for chromatographic analysis are often too aggressive. Often, not only fragile colours (dyestuffs) like carrotenoids (present in for example; annatto seeds and safflower floss) are destroyed during the extraction. Likewise coloured sugars could be lost or even transformed into another new molecule. Preserving these sugars by using a soft extraction technique could be extremely useful as the sugars could provide information about the original botanical or biological source, also provide information about how the dye or pigment was prepared or something about the environment in which the plant or insect/mollusk source existed.

Rubiaceae: Dyestuff, repellents and museum bugs

,… Another remarkable component present in some Rubia species and in particular Rubia tinctorum L. (Madder) is lucidin-3-O-primeveroside. This particular component drives off the varied carpet beetle (Anthrenus verbasci L.) called in dutch ‘Museumkever’ because it is considered a pest because it not only scavenges on other dead insects but also hair, feathers, natural fibers and dead skin, it leaves its eggs in tapestries and woolly objects leaving a black corroded areas when it hatches.