NATURAL DYE YIELDING POTENTIAL AND COMPOUNDS OF SELECTED VEGETABLE RESIDUES BELONGING TO BRASSICACEAE: AN APPROACH TOWARDS SUSTAINABILITY

The cruciferous vegetables are well known for their ethnobotanic and economic importance throughout the world. Traditionally, the members of Brassicaceae are used as vegetables, food plants, ornamentals as well as source of oil and natural dyes. Though there are evidences regarding the historic use of Brassicaceae plants for coloring of various items but information for utilization of these in modern textile dyeing is negligible. Current study is concerned with the utilization of residual material of Brassica oleracea L.var. capitata (cabbage), Brassica oleraceae L. var. botrytis (cauliflower) and Brassica rapa L. var. purple top (turnip) to achieve maximum dye yielding potential as well as determine their phytochemical nature. Results revealed that colorants of varying shades could be extracted from above mentioned plant residues using different extraction media (acidic, alkaline, aqueous and organic). Variety of color shades including light brown, brown, yellowish green, yellow, dark green, creamy white, light green, olive green and dark brown could be produced from these plant residues using eco friendly bio as well as chemical mordants. The analysis of these plant residues revealed the presence of flavonoids, tannins, alkaloids, saponins, carbohydrates, sugars and glycosides. Stability of these vegetable residues based colorants in terms of fastness properties including wet rubbing, washing, dry rubbing and light fastness proved to be good to excellent.