Determination of the uses of different extracts from Juglans regia L. green shells as dyeing agents

Juglans regia L. barks are commonly known as plant parts that are mostly discarded as waste in the environment. In this study, different dyes were obtained from these plant parts, and various dyeing properties of these dyes were determined. Extracts were obtained from the waste walnut barks using six different solvents, namely water, methanol, ethanol, ethyl acetate, hexane, and chloroform, and their contents were analyzed by HPLC. The dye properties were tested on 100% cotton, untreated, three-ply raw fabric with and without mordant, using Iron III chloride as the mordant. The retention values were calculated based on the weights of the fabric before and after dyeing. The colorimetric measurements of the dyed fabrics were calculated by measuring the L*, a*, b* values. Lightfastness and rub fastness tests were performed. The maximum absorbance values of the extracts were determined spectrophotometrically. Furthermore, surface analysis of the components was carried out using FTIR analysis. The antimicrobial activities of the extracts against different microorganisms were evaluated using the disk diffusion method. At the end of the study, it was determined that the extracts did not show significant antimicrobial activity but contained certain phenolic compounds. Different color scales were observed between the white and brown tones of the dyed fabrics. As a result, it was concluded that these substances containing beneficial polyphenols, which do not exhibit activity against any microorganism, can be used as dyes, thereby allowing the development of high-value products from waste materials.