Antibacterial properties and color fastness of silk fabric dyed with turmeric extract

The use of non-toxic and eco-friendly natural dyes on textiles has received much attention due to the increased environmental awareness in order to avoid some hazardous synthetic dyes. In the present study, an eco-friendly approach was developed to impart color and antibacterial properties to silk fabrics dyed with turmeric extract as a non-toxic natural colorant. The natural colorant was extracted from Curcuma Longa rhizome. Copper sulfate, ferrous sulfate and potassium aluminium sulfate were applied in a pre-metallization process as mordanting agents. Antibacterial properties of treated fabrics were evaluated against common pathogenic bacteria, Staphylococcus aureus (Gram-positive) and Escherichia coli (Gram-negative). The effects of dye concentration and mordant types on the obtained color hues, antibacterial efficiency and color fastness of the fabrics were investigated. The results indicated that mordanted and dyed fabrics possessed desirable antibacterial properties. Complete antibacterial activity of the treated fabrics was obtained with 3 %owf (on weight of the fabric) copper sulfate. It was also shown that increasing the dye concentration could lead to a more efficient antibacterial activity on the mordanted dyed fabrics. An optimum level of the antibacterial activity was observed in the sample treated with 30 %owf of turmeric. Furthermore, the results of CIE L*, a*, b* values, FTIR, washing, light and rubbing fastnesses of the dyed fabrics were reported. The mordanted dyed silk fabrics exhibited desirable color fastness properties. These studies proved a direct relationship between the degree of antibacterial activity of the fabrics treated with turmeric and the metals ion concentration.