Potential of Aeromonas
dhakensis in bioremediation of an Azo and Untreated Dye effluent sample
Shaikh Afreen and Birmole Radhika
Res. J. Biotech.; Vol. 20(9); 283-291;
doi: https://doi.org/10.25303/209rjbt2830291; (2025)
Abstract
The residual dyes in textile effluents are not efficiently remediated by conventional
physical and chemical methods due to the presence of a mixture of compounds, most
of which have complex structures. Consequently, the overall environmental impact
of textile effluents is a global concern. Biological treatment interventions are
currently encouraged since some micro-organisms can utilize dye molecules as a sole
source of carbon and nitrogen. In the present study, the dye effluent collected
from local industrial areas in Mumbai was screened for bacteria capable of degrading
Remazol Deep Black GWF (RDB-GWF) dye. It is a reactive sulphonated diazo dye commonly
used in the textile industries.
The most promising bacterial strain with dye decolorizing potential was identified
as Aeromonas dhakensis based on 16S rRNA gene sequence analysis. A. dhakensis showed
optimum decolorization (84.08 %) when 4% inoculum of 0.8 O.D (at 540nm) was added
to Luria Bertani (pH 9.0) medium containing 1% NaCl and incubated at 30°C for 24
h under shaker (120rpm) conditions. The strain showed tolerance up to 300ppm dye
concentration and significantly decolorized untreated textile effluent sample. The
degradation of dye was confirmed by FTIR spectroscopic analysis. Phytotoxicity studies
(with Phaseolus mungo and Triticum aestivum) suggested non-toxic nature of degraded
metabolites.
