Cell‐Free Culture Broth of Pseudomonas aeruginosa—An Alternative Source of Biodispersant to Synthetic Surfactants for Dyeing the Polyester Fabric

Abstract

AbstractConventional synthetic dispersants have extensively been used in various textile processes due to their easy availability and cost effectiveness. Nonetheless, due to environmental concerns, researchers are trying to explore ecofriendly dispersants such as biosurfactants as substituents to synthetic surfactants. Currently, biosurfactants are not economical due to the cost of their downstream processing and laborious purification steps. Herein, we employed as‐collected cell‐free culture broth (CFCB) of a Pseudomonas aeruginosa strain being an indigenous source of rhamnolipid surfactants (as biodispersant) for disperse‐dyeing of polyester fabric in comparison with some commercially available synthetic surfactants (such as Triton X‐100, cetyltrimethylammonium bromide “CTAB” and sodium dodecyl sulfate ‘SDS’). The efficiency of biosurfactant‐enriched culture broth was compared with that of synthetic surfactants for the said purpose. In addition to conventional testing, dyed fabrics were characterized using scanning electron microscopy (SEM), x‐ray diffraction, and surface resistivity analyses. It was observed that the fabric specimen dyed at 1.5% dye concentration on the weight of the fabric (o.w.f.) in the presence of CFCB (containing biosurfactant above‐CMC) resulted in excellent tensile and colorfastness properties. The SEM analysis indicated that the dyeing done in the presence of biosurfactant was safer as it did not damage the fabric surface as observed in synthetic dispersants; moreover, the mechanical and color characteristics of dyed fabric were also in the acceptable range.