"Bacterial consortium from hydrothermal vent sediments presents electrogenic activity achieved under sulfate reducing conditions in a microbial fuel cell"

Margarita Isabel Pérez-Díaz; Paola Zárate-Segura; Luis Antonio Bermeo-Fernández; Khemlal Nirmalkar; Fernando Bastida-González; Jaime García-Mena; Janet Jan-Roblero; Claudia Guerrero-Barajas

doi:10.1007/s40201-020-00537-1

"Bacterial consortium from hydrothermal vent sediments presents electrogenic activity achieved under sulfate reducing conditions in a microbial fuel cell"

J Environ Health Sci Eng. 2020 Sep 11;18(2):1189-1205. doi: 10.1007/s40201-020-00537-1. eCollection 2020 Dec.

Authors

Margarita Isabel Pérez-Díaz^#¹, Paola Zárate-Segura^#², Luis Antonio Bermeo-Fernández¹, Khemlal Nirmalkar³, Fernando Bastida-González², Jaime García-Mena³, Janet Jan-Roblero⁴, Claudia Guerrero-Barajas¹

Affiliations

¹ Laboratorio de Biotecnología Ambiental Posgrado. Departamento de Bioprocesos. Unidad Profesional Interdisciplinaria de Biotecnología (UPIBI), Instituto Politécnico Nacional, Av. Acueducto s/n, Col. Barrio la Laguna Ticomán, 07340 Mexico City, Mexico.
² Laboratorio de Medicina Traslacional, Escuela Superior de Medicina, Instituto Politécnico Nacional, Plan de San Luis y Díaz Mirón s/n, Col. Santo Tomas, 11340 Mexico City, Mexico.
³ Departamento de Genética y Biología Molecular, CINVESTAV - IPN, Av. IPN # 2508, Col. Zacatenco, 07360 Mexico City, Mexico.
⁴ Laboratorio de Biotecnología Ambiental. Departamento de Microbiología, Escuela Nacional de Ciencias Biológicas, Instituto Politécnico Nacional, Prol. de Carpio y Plan de Ayala s/n, Col. Santo Tomás, 11340 Mexico City, Mexico.

^# Contributed equally.

Abstract

Purpose: The aim of the present work was to assess the electrogenic activity of bacteria from hydrothermal vent sediments achieved under sulfate reducing (SR) conditions in a microbial fuel cell design with acetate, propionate and butyrate as electron donors.

Methods: Two different mixtures of volatile fatty acids (VFA) were evaluated as the carbon source at two chemical oxygen demand (COD) proportions. The mixtures of VFA used were: acetate, propionate and butyrate COD: 3:0.5:0.5 (stage 1) and acetate - butyrate COD: 3.5:0.5 (stage 2). Periodical analysis of sulfate (SO₄ ^-2), sulfide (HS^-) and COD were conducted to assess sulfate reduction (SR) and COD removal along with measurements of voltage and current to assess the global performance of the consortium in the system.

Results: Percentage of SR was of 97.5 ± 0.7 and 74.3 ± 1.5% for stage 1 and 2, respectively. The % COD removal was of 91 ± 2.1 and 75.3 ± 9.6 for stage 1 and 2, respectively. Although SR and COD removal were higher at stage 1, in regards of energy, stage 2 presented higher current and power densities and Coulombic efficiency as follows: 741.7 ± 30.5 μA/m², 376 ± 34.4 μW/m² and 5 ± 2.7%, whereas for stage 1 these values were: 419 ± 71 μA/m², 52.7 ± 18 μW/m² and 0.02%, respectively. A metagenomic analysis - stage 2 - in the anodic chamber, demonstrated that SR was due to Dethiosulfovibrionaceae (HA73), Desulfobacter and Desulfococcus and the electrogenic microorganisms were Planococcus, SHD-231, Proteiniclasticum, vadinCA02, and families Porphyromonadacea and Pseudomonadaceae.

Conclusions: It was demonstrated that microorganisms prevenient from hydrothermal vent sediments adapted to a microbial fuel cell system are able to generate electricity coupled to 74.3 ± 1.5 and 75.3 ± 9.6% of SR and COD removal respectively, with a mixture of acetate - butyrate.

Keywords: Electrogenic microorganisms; Hydrothermal vent sediments; Microbial fuel cell; Sulfate reduction; UASB reactors.