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Natural dyes can be classified in following groups on the basis of sources (Figure 1.2) [33]:

Figure 1.2 Sources of natural dyes.

1 Plants: Roots, leaves, fruits, flowers and barks can be used as a source of natural dyes. Different colors can be obtained from each part such as Sappan-wood tree pods give red, barks give brown and root gives yellow color. Many by-products of plants can also be used to form dyes.

2 Animals: Dyes can be obtained from dried body of insects for example, Lac, Cochineal and Kermes. Cochineal is a brilliant red dye produced from insects living on Cactus plants. Carmine and Tyrian purple dye derived from cochineal, shellfish (Murex spp.) respectively.

3 Minerals: Mineral dyes include iron buff, iron black, manganese bistre, chrome yellow, and Prussian blue.

4 Microorganisms: Natural colorant can be extracted from fungi, bacteria and algae that are fast growing and have the potential of being standardized commercially [34]. Chitosan, Serratia spp., Trichoderma virens and Alternaria alternata were used to obtained dyes [35]. Natural Red color is produced by Monascus anka and also from fungus Echinodontium tinctorium. Phycocyanin is blue pigment extracted from Spirulina plarensis algae.