Preliminary Investigation of a Colouring Matter Extract from Sorghum Bicolor Sheaths and its Application to Textile Subtrates

Abstract

The colouring matter from the sheath of sorghum bicolor was extracted using ethanol, acetone, water and petroleum ether, respectively. Ethanol exhibited higher extract percentage yield compared to the other solvents with petroleum ether giving the least. The chromatographic analysis indicates that the extract contains only one component which maximally absorbs at 1.78 and 1.58 in ethanol and water, respectively. The extracted colouring matter was applied to cotton, nylon, and wool fabrics with better results obtained on nylon fabric. The use of Potassium Chromate as a mordant however, generally improves the colour yield on the nylon and with improved wash fastness properties in all the fabrics used.