Antibacterial activity of some selected dye yielding plants in Eastern India

Abstract

Acacia catechu (L.) Willd. (Mimosaceae), Pterocarpus marsupium Roxb. (Papilionaceae), Toddalia asiatica (L.) 
Lamk. (Rutaceae) and Ventilago denticulata Willd. (Rhamnaceae), growing in West Midnapore district of West 
Bengal, an eastern state of India, yields dyes which showed strong antimicrobial activity against four bacterial 
strains (Bacillus cereus, Escherichia coli, Klebsiella pneumoniae and Vibrio cholerae). Among the dyes of the 
four plants tested, Toddalia asiatica showed the highest antimicrobial activity with the inhibition zones ranging 
from 14 to 16 mm. Thin layer chromatography of the dyes, which were either substantive dyes or adjective type 
of dyes requiring mordents for fixing to fabrics, showed that most of these pigments were composed of 
xanthophylls and anthocyanin. The extracts of different plant parts are also used for various medicinal purposes 
by the local tribal people. The over exploitation of these plants for dyeing and pharmaceutical uses has led to the 
depletion of these species, particularly P. marsupium and V. denticulata, from this region and immediately 
demands more focused conservation strategies.