Natural Dyes and Pigments: Sustainable Applications and Future Scope

Natural dyes and pigments are gaining importance as a sustainable alternative to synthetic dyes. Sourced from renewable materials, they are known for their biodegradable and non-toxic properties, offering a diverse range of color profiles and applications across industries such as textiles, cosmetics, food, and pharmaceuticals. This manuscript discusses various aspects of natural dyes and pigments (derived from plants and microbes), including anthocyanins, flavonoids, carotenoids, lactones, and chlorophyll. Furthermore, it highlights the polyphenolic nature of these compounds, which is responsible for their antioxidant activity and contributes to their anticancer, antibacterial, antifungal, antiprotozoal, and immunomodulatory effects. However, natural dyes are often categorized as pigments rather than dyes due to their limited solubility, a consequence of their molecular characteristics. Consequently, this manuscript provides a detailed discussion of key structural challenges associated with natural dyes and pigments, including thermal decomposition, photodegradation, photoisomerization, cross-reactivity, and pH sensitivity. Due to these limitations, natural dyes are currently used in relatively limited applications, primarily in the food industry, and, to lesser extent, in textiles and coatings. Nevertheless, with ongoing research and technological innovations, natural dyes present a viable alternative to synthetic dyes, promoting a more sustainable and environmentally conscious future.