Valorization of floral waste for anthocyanin-based textile dyeing: Extraction techniques, mordanting strategies and fastness performance – A review

The increasing environmental concerns associated with synthetic dyes have renewed interest in natural colourants derived from renewable resources. Floral waste generated from temples, religious ceremonies and decorative industries represents an underutilized biomass with significant potential for sustainable dye production. Among flower derived pigments, anthocyanins have gained considerable attention due to their vibrant colour range, biodegradability and eco-friendly characteristics. However, challenges related to extraction efficiency, dye-fiber interactions, mordant dependency, pigment stability and colour fastness continue to limit their large-scale industrial application. This review critically examines the current research on floral-based natural dyes with particular emphasis on anthocyanin extraction techniques, optimization approaches including Response Surface Methodology (RSM), mordanting strategies and their influence on dye fixation and colour fastness properties. In addition, the review discusses dye application on various textile substrates and evaluates the performance of natural dyes under different fastness conditions. The study highlights recent technological advancements, identifies research gaps and outlines future prospects for integrating floral waste-derived dyes into sustainable textile processing within a circular bioeconomy framework.