Abstract:
Natural pigments are coloured compounds obtained from natural sources such as plants, microorganisms, and some animals. Plant pigments are particularly important because plants contain a diverse range of compounds capable of producing different colours.The major groups of plant pigments include chlorophylls, carotenoids, anthocyanins, betalains, and several other phenolic compounds. Chlorophyll is mainly responsible for the green colour of leaves and is essential for photosynthesis. Carotenoids produce yellow, orange, and some red colours and are found in many fruits, vegetables, flowers, and leaves. Anthocyanins are responsible for a wide range of red, purple, violet, and blue colours, while betalains produce red-violet and yellow colours in certain plants.Natural pigments differ in their chemical structures and therefore show different physical and chemical properties. Some pigments are soluble in water, whereas others show greater solubility in organic solvents. Similarly, some pigments are relatively stable under particular environmental conditions, while others are highly sensitive to pH, temperature, light, or oxygen.
The study of natural pigments is therefore important not only for understanding plant chemistry but also for exploring their possible applications. The recovery of pigments from plant materials can provide an approach for utilizing naturally occurring compounds that may otherwise remain underused.
Description:
Colour is one of the most noticeable characteristics of plants and plays an important role in the natural environment. The attractive colours of flowers, fruits, leaves, seeds, roots, and other plant parts are mainly due to the presence of naturally occurring pigments. These pigments are chemical substances that absorb certain wavelengths of visible light and reflect others, producing the colours perceived by the human eye. Plant pigments are not merely responsible for the visual appearance of plants; they also perform several important biological functions.Plants contain a wide variety of pigments that participate in processes such as photosynthesis, protection against excessive light, defence against environmental stresses, and attraction of pollinators and seed-dispersing organisms. The diversity of plant pigments results in the wide range of colours observed in nature, from the green of leaves to the yellow, orange, red, purple, and blue colours of flowers and fruits.
Natural pigments have been used by humans since ancient
