Optimization of Culture Conditions
for Enhanced Decolorization of Azo Dyes
by Aspergillus flavus Isolated from Dye
Contaminated Soil
M. Dexilin, B. Gowri Manogari, and Thamaraiselvi Kaliannan
Abstract Dyes released by the textile industries pose a threat to the environmental
safety. Recently, dye decolorization through biological means has gained impetus
as these are cheap and can be applied to wide range of dyes. The main focus of the
present investigation is to evaluate the bioremediation potential of Aspergillus flavus
isolated from textile dye contaminated soil for the decolorization of synthetic acid
dyes. Among the isolated four fungal strains namely Aspergillus flavus, Fusarium
oxysporum, Rhizopus sp. and Aspergillus terrus, Aspergillus flavus was capable of
decolorising 96 and 97% for Acid Blue (AB) 193 and Acid Violet (AV) 90, respectively under optimum conditions of pH 6.0 and temperature 25 °C. Hence from
the results, it can be concluded that this fungus can be used as eco-friendly and
economically effective tool to decolorize textile dye effluents.
Keywords Acid blue 193 · Acid violet 90 · Aspergillus flavus · Decolorization ·
Effluent
1 Introduction
Synthetic dyes are widely used in textile dyeing, paper printing, color photography,
pharmaceutical, food, cosmetic and leather industries (Rafii et al. 1990; Kuhad
et al. 2004; Rodriguez Couto 2009). Since 1856, over 105 different dyes have been
produced worldwide with an annual production of over 7 × 10
5 metric tons (Chen
et al. 2003). Of all the familiar dyestuffs in the world, azo dyes make up about a
half, making them the largest group of synthetic colorants that are released into the
environment (Zhao and Hardin 2007; Sen et al. 2016). Effluents from the textile
industries containing dye are highly coloured and are therefore visually identifiable
(Kılıç et al. 2007) and are visible even at 1 mg/ml concentration (Pandey et al.
2007). The discharge of colored effluents into the environment is detrimental, not
M. Dexilin · B. Gowri Manogari · T. Kaliannan (B)
Laboratory of Molecular Bioremediation and Nanobiotechnology, School of Environmental
Sciences, Department of Environmental Biotechnology, Bharathidasan University, Tiruchirappalli
- 620 024, Tamil Nadu, India
e-mail: kthamaraiselvi@hotmail.com
© The Author(s), under exclusive license to Springer Nature Switzerland AG 2021
M. Prashanthi et al. (eds.), Bioremediation and Green Technologies, Environmental
Science and Engineering, https://doi.org/10.1007/978-3-030-64122-1_11
143
for Enhanced Decolorization of Azo Dyes
by Aspergillus flavus Isolated from Dye
Contaminated Soil
M. Dexilin, B. Gowri Manogari, and Thamaraiselvi Kaliannan
Abstract Dyes released by the textile industries pose a threat to the environmental
safety. Recently, dye decolorization through biological means has gained impetus
as these are cheap and can be applied to wide range of dyes. The main focus of the
present investigation is to evaluate the bioremediation potential of Aspergillus flavus
isolated from textile dye contaminated soil for the decolorization of synthetic acid
dyes. Among the isolated four fungal strains namely Aspergillus flavus, Fusarium
oxysporum, Rhizopus sp. and Aspergillus terrus, Aspergillus flavus was capable of
decolorising 96 and 97% for Acid Blue (AB) 193 and Acid Violet (AV) 90, respectively under optimum conditions of pH 6.0 and temperature 25 °C. Hence from
the results, it can be concluded that this fungus can be used as eco-friendly and
economically effective tool to decolorize textile dye effluents.
Keywords Acid blue 193 · Acid violet 90 · Aspergillus flavus · Decolorization ·
Effluent
1 Introduction
Synthetic dyes are widely used in textile dyeing, paper printing, color photography,
pharmaceutical, food, cosmetic and leather industries (Rafii et al. 1990; Kuhad
et al. 2004; Rodriguez Couto 2009). Since 1856, over 105 different dyes have been
produced worldwide with an annual production of over 7 × 10
5 metric tons (Chen
et al. 2003). Of all the familiar dyestuffs in the world, azo dyes make up about a
half, making them the largest group of synthetic colorants that are released into the
environment (Zhao and Hardin 2007; Sen et al. 2016). Effluents from the textile
industries containing dye are highly coloured and are therefore visually identifiable
(Kılıç et al. 2007) and are visible even at 1 mg/ml concentration (Pandey et al.
2007). The discharge of colored effluents into the environment is detrimental, not
M. Dexilin · B. Gowri Manogari · T. Kaliannan (B)
Laboratory of Molecular Bioremediation and Nanobiotechnology, School of Environmental
Sciences, Department of Environmental Biotechnology, Bharathidasan University, Tiruchirappalli
- 620 024, Tamil Nadu, India
e-mail: kthamaraiselvi@hotmail.com
© The Author(s), under exclusive license to Springer Nature Switzerland AG 2021
M. Prashanthi et al. (eds.), Bioremediation and Green Technologies, Environmental
Science and Engineering, https://doi.org/10.1007/978-3-030-64122-1_11
143