International Journal of Agricultural Sciences ISSN 2167-0447 Vol. 10 (12), pp. 001-009, December, 2020. © International Scholars Journals

Full Length Research Paper

Comparative study of the major components of the indigo dye obtained from Strobilanthes flaccidifolius Nees. and Indigofera tinctoria Linn.

Warjeet S. Laitonjam* and Sujata D. Wangkheirakpam

Department of Chemistry, Manipur University, Canchipur – 795 003, Manipur, India.

Accepted 15 October, 2020

Abstract

Investigation on the chemical constituents including the chemical structure of major components in the water extracts from Strobilanthes flaccidifolius Nees. and Indigofera tinctoria Linn. was done. It was found that the indigo from fresh leaves of S. flaccidifolius Nees. fermented for three days gave the highest amount of indigo. The thin layer chromatography of the crude extract revealed four pigments; the major pigments were of red and blue having Rf values of 0.88 and 0.76, respectively. The Rf value, the maximum absorption from UV-Visible spectroscopy and infra red spectrum of blue pigment were the same as those of the standard indigo. Both blue and red pigments are highly soluble in chloroform whereas only red pigment is soluble in methanol.

Key words: Comparative study, Strobilanthes flaccidifolius Nees., Indgofera tinctoria Linn., indigo.