Dye plants of Madagascar, color potential to replace artificial textile dyes

The textile industry is one of the most polluting in the world, mainly due to wastewater discharges from dyeing with petrochemical dyes.In recent years, there has been a trend towards the use of natural fibers and dyes, and a move towards the bioeconomy.Madagascar is home to some one hundred dye plants that also deserve to be valorized in this field.The aim of this study is to assess the potential of a number of Madagascar plants for dyeing natural fibers such as wool and cotton, using different types of mordants.The study will focus on experiments carried out with four different species with potential sources of different colors, including Psiadia altissima, Eugenia jambos, Passiflora subpeltata and Aphloia theiformis.The extracts obtained by aqueous extraction were tested with five types of mordants: alum, FeSO4, CuSO4, tartaric acid and ash.Dye fastness was assessed by means of wash fastness tests.A color range of blue, green and yellow was obtained.Wash fastness varies according to plant and mordant.Good fastness was observed for cotton dyed directly with Eugenia jambos and wool mordanted with CuSO4.More studies on improving fastness are needed, but this new knowledge of Madagascar plants could be a starting point for their application in the textile industry.