Enhanced textile dye removal from wastewater using natural biosorbent and Shewanella algae B29: Application of Box Behnken design and genomic approach

Abstract

In this study, Box-Behnken design combining seven factors at three levels were used to optimize the elimination of CI Reactive Red 66 in artificial seawater, by the combination of eco-friendly bio-sorbents and acclimated halotolerant microbial strain. Results showed that macro-algae and cuttlebone (2 %) were the best natural bio-sorbent. Additionally, the selected halotolerant strain able to rapidly remove dye was identified as Shewanella algae B29. The optimization process revealed that decolourization of CI Reactive Red 66 yields reached 91.04 % under the following variable values: dyes concentration (100 mg/l), salinity (30 g/l), peptone (2 %), pH (5), algae C (3 %), cuttlebone (1.5 %) and agitation (150 rpm). The whole genome analysis of S. algae B29 demonstrated the presence of several genes coding for valuable enzymes involved in textile dyes biotransformation, adaptation to stress as well as biofilm formation implying its potential use in biological textile wastewater treatment.