Table 3.
Classification of natural dyes according to their chemical structure and source.
| Color | Classification | Source | Example | Reference |
|---|---|---|---|---|
| Yellow/ Orange/ Red |
Curcumin | Plant/Vegetable | Turmeric (Curcuma longa L.) | [348] |
| Carotenoids | Plant/Vegetable | Carrot (Daucus carota L.), Annatto (Bixa orellana), Tomato (Solanum lycopersicum), Paprika (Capsicum annuum L.), petals of marigold (Tagetes erecta L.) | [349,350] | |
| Aryl carotenoids | Microorganisms | Brevibacterium linens, Streptomyces mediolani, Mycobacterium aurum | [351] | |
| Red/Pink | Betalains | Plant/Vegetable | Beetroot (Beta vulgaris L.), Opuntia lasiacantha | [339,349] |
| Carminic acid | Microorganisms | Cochineal (Dactylopius coccus) | [350] | |
| Anthocyanins | Plant/Vegetable | Hibiscus rosa sinensis flowers | [352] | |
| Blue/ Purple |
Anthocyanins | Plant/Vegetable | Grapes (Vitus labruscana L.), red cabbage (Brassica oleracea var. capitata f. rubra), cherry (Prunus cerasus), blueberry (Vaccinium sect. Cyanococcus), red onion skin (Allium cepa L.), Beetroot (Beta vulgaris L.) | [323,326,350] |
| Tyrian purple (6,6′-dibromoíndigo) | Animal | Mollusks Bolinus brandaris | [349] | |
| Ultramarine Blue | Mineral | Lapis lazuli | [349] | |
| Green | Chlorophylls | Plant/Vegetable | Spinach (Spinacia oleracea), kiwi pomace (Actinidiaceae), green beans (Phaseolus vulgaris), grass, alfalfa (Medicago sativa) | [57,350] |
| Terre-Verte (Green Earth) | Mineral | Mixture of hydrosilicates of Fe, Mg, Al, and K (gluconite and celadenite) but other minerals are likely to be present | [349] | |
| Malachite | Copper carbonate hydroxide |