A novel basydiomycete isolated from mangrove swamps in the Colombian Caribbean shows promise in dye bioremediation

Abstract

Ligninolytic fungi derived from coastal and marine environments, particularly mangrove swamps, are considered potential sources of novel enzymes with unique properties (thermostability, high-redox potential, salt and pH tolerance) not found in terrestrial strains, which are very attractive for the development of effective solutions for the elimination of contamination caused by the textile industry. In this study, the isolation and ligninolytic screening of 73 fungal strains derived from mangrove swamps were achieved. Ten strains showed ligninolytic potential, among which, the basidiomycete identified as INV BAS1 (Cyphellaceae family) exhibited outstanding laccase activity (11873.8 ± 329.0 UL⁻¹). The laccase production was enhanced (5-fold) by optimizing the medium components concentration using a statistical design that combined the one factor at a time method and a central composite rotational design (CCRD), under Response Surface Methodology (RSM). Decolorization of the recalcitrant textile dye Remazol Briliant Blue R (RBBR) was carried out through fermentation and the use of enzyme extracts, reaching decolorization percentages of up to 95.64 ± 1.28 %, under alkaline and high salinity conditions. The laccase activity in the bulk extracts was the major responsible for the RBBR degradation according to gel zymography, UV-Vis and ATR-FTIR spectroscopy. These results contribute to the knowledge of fungal diversity in tropical mangroves and confirm their potential for the development of new bioremediation strategies in high-salt and alkaline effluents generated by the textile industry.

Keywords:

• Agro-industrial-waste
• CCD
• central composite design
• Colombian Caribbean
• Cyphellaceae
• laccase
• mangrove swamp
• marine - coastal derived fungi
• RSM
• response surface methodology
• synthetic dye
• textile industry

Acknowledgments

The authors acknowledge to the “Ministerio de Ambiente y Desarrollo Sostenible de Colombia (Minambiente)” and to the Marine and Coastal Research Institute “José Benito Vives de Andréis” – INVEMAR for the financial support (Contribution No. 1305). Authors are also thankful to the evaluation and use of Marine and Coastal Resources Program-VAR and members of the Marine Bioprospecting Line from INVEMAR for their collaboration and advice in the collection, isolation and cryopreservation of fungal strains, as well as in the IR spectroscopy experiments.

Author’s contributions

Jutinico-Shubach L. Conceived and designed the experiments, Performed the experiments, Analyzed and interpreted the data, Wrote the paper. Castaño J. Conceived and designed the experiments, Performed experiments, Analyzed and interpreted the data, Reviewed the work critically. Juárez T. and Mariño M. Performed the experiments, Analyzed and interpreted the data, both authors contributed equally to this work. Gómez-León J. Supervised the research work, Reviewed the manuscript critically, contributed reagents, materials and analysis tools. Blandón L. Conceveid and designed the experiments, Analyze and interpreted the data, Supervised the research work, Contributed reagents, materials and analysis tools, Reviewed the work critically.

Disclosure statement

The authors approved the final manuscript, they report no potential conflict of interest and declare that it has not been published previously.

Ethical statement

This research was carried out within the framework of the Contract (Contrato marco de acceso a recursos genéticos y sus productos derivados No. 123; Expediente RGE 0158-5) granted to the Marine and Coastal Research Institute “José Benito Vives de Andréis” – INVEMAR by the Ministerio de Ambiente y Desarrollo Sostenible de Colombia (Minambiente).