ABSTRACT
Natural dyes have a natural origin, while synthetic dyes are from organic molecules and are made up of chemical compounds that may be harmful to human health due to their toxic nature. Textile industries have been using synthetic dyes in colouring fabrics for a long period of time. Recently, natural dyes have become of interest due to the health hazards associated with the synthetic dyes. The degradation of synthetic dyes produces a lot of by-products that are associated with health hazards, whereas such hazardous compounds have so far not been found in by-products of natural dye degradation. Flavoparmelia caperata is a lichen species that has been evaluated for its anti-fungal, anti-bacterial, anti-inflammatory, and cytotoxic effects. This study focuses on the application of dye from the lichen extract on a cellulosic fabric with and without a mordant. The dye was extracted using boiling water method (BWM) and ammonia fermentation method (AFM) where both resulted in a brown coloured extract. Phytochemical screening confirmed the presence of flavonoids, fixed oils, anthraquinones, terpenoids, tannins, steroids and alkaloids. The dye was applied on a cotton fabric and assessed for colour fastness properties to wash, light, and rub. The dyed fabrics were brown with extract from BWM and light purple from AFM without a mordant, on mordanting the purple colour darkened. The extract from AFM mordanted fabrics showed best results upon colour fastness tests to rubbing and washing of 3–5 while extracts from BWM displayed best results on light of 5 against a standard grey scale of 1–5, which is above the acceptable levels of 3. Vinegar was used as a mordant. Flavoparmelia caperata is therefore a good source of phytochemicals and it has potential for dyeing cotton fabrics.
