Recently, the Haihong Song's team from the School of Chemistry and Chemical Engineering (School of Carbon Neutrality Future Technology) at Shantou University made new progress in the research field of "biological decolorization of azo dye wastewater and biofilm reactor technology". The related research findings were published under the title "Microbially mediated cleavage of Reactive Black 5 in attached growth bioreactors with immobilized Shewanella indica strain on different carriers" in International Biodeterioration & Biodegradation (impact factor 4.4), a well-established international journal in the field of biodegradation and environmental biotechnology.

Paper link: https://www.sciencedirect.com/science/article/abs/pii/S0964830520310738

Paper title: Microbially mediated cleavage of Reactive Black 5 in attached growth bioreactors with immobilized Shewanella indica strain on different carriers

Authors: Xinxin Zhang, Haihong Song*, Yong Chen, Mei Zhuang, Wenhua Liu

Corresponding author: Haihong Song (E-mail: hhsong@stu.edu.cn)

Journal: International Biodeterioration & Biodegradation

Year, volume, article number: 2021, Volume 157, Article 105142

DOI: https://doi.org/10.1016/j.ibiod.2020.105142

Keywords: Azo dye; Bacteria immobilization; Degradation metabolites; Shewanella indica strain; Textile wastewater treatment

English abstract of the paper:

Decolorization and removal of contaminants in textile wastewater are essential for pollution control. This study investigated the potential application of a halophilic and halotolerant Shewanella indica (S. indica) strain as immobilized biofilm in two attached growth bioreactors with moving bed bioreactor carrier and polyurethane porous gel carrier, respectively. Under optimized operation conditions, both bioreactors had high tolerance for Reactive Black 5 (RB5) concentration fluctuation and could decolorize RB5 effectively and stably (97% on average) for over 6 months. The decolorization of RB5 in bioreactors was mainly due to microbially mediated cleavage of the azo dye, though adsorption by biofilm and carrier (contribution of different carriers varied) also contributed to the process. However, the azo dye was barely mineralized, and the toxicity remained after decolorization. Overall, this study demonstrated the viability and sustainability of the bioreactors incubated with S. indica in decolorizing RB5. Nevertheless, further technologies need to be explored to detoxify the degradation metabolites.