Augmentation of chloramphenicol degradation by Geobacter-based biocatalysis and electric field

Abstract

Electroactive microorganisms and electrochemical technologies have been separately used for environmental remediation such as antibiotics removal, yet the efficiency of coupling these two methods for chlorinated antibiotics removal is poorly known. Here we tested the synergy of Geobacter sulfurreducens PCA, an electroactive bacteria, and an electrical field, on chloramphenicol removal. Removal is increased two-fold by increasing the temperature from 30 • C to 37 • C. The cyclic voltammograms and chronoamperometry tests demonstrated that G. sulfurreducens PCA catalyzed chloramphenicol chemical reduction with electrode as excusive electron donor. A critical voltage, − 0.6 to − 0.5 V vs. Ag/AgCl, was discovered for chloramphenicol degradation with an increase of removal rate about 2.62-folds, from 31.06% to 81.41%. Combined removal with both G. sulfurreducens PCA and an electrical field increased the apparent rate constant and reached 82.77% removal at − 0.5 V. Specially, the combined removal at − 0.5 V even presented more robust removal efficiency compared to − 0.6 V (78.64%) without G. sulfurreducens PCA. Mass spectrometry of degradation products indicates the reduction of nitro into amine groups, and dechlorination into less toxic compounds. Overall, combined biocatalysis and an electrical field is a promising method to remove antibiotics from polluted environments.

Optimization of the elimination of antibiotics by Lemna gibba and Azolla filiculoides using response surface methodology (RSM)

“…Similarly, a study in which Azolla was exposed to a drug (diclofenac) at different doses (0.1, 1, 10, and 100 mg/L) for different periods of time (24, 48, 72, and 240 h) found that time and dose influenced the toxicity of Azolla, resulting in lower removal for the medium (Vannini et al, 2018). Another study showed that a higher concentration decreased the removal rate (Xiao et al, 2021).…”

Advantage of conductive materials on interspecies electron transfer-independent acetoclastic methanogenesis: A critical review

“…Alternatively, electroactive microorganisms that lack e-pili and other electron-bridging organs can still perform DIET artificially by addition of conductive materials such as carbon-based conductors or metals to the medium [16,59]. Here electrons are transferred at the material surface, which is supported by Shrestha et al [91] who found a correlation of r of 0.67 between abundance of Geobacter spp., where Geobacter can also accept electrons from abiotic resource [116], and granule conductivity. Other studies also showed that enhanced methane production by conductive materials is correlated with electron redox transfer [139].…”

Quorum sensing signals from sludge improving the self-assembly of electrode biofilms in microbial fuel cells for chloramphenicol degradation

“…1,2 Chloramphenicol (CAP), a kind of chlorinated nitroaromatic antibiotic, is broadly used in animal husbandry and aquaculture because of its effective antimicrobial capacity and low price, leading to its ubiquity in various aquatic environments. 3 Hence, diverse treatment techniques for CAP removal from water matrices have been developed, for example, adsorption, 4 advanced oxidation, 5 photocatalytic degradation, 6 electrochemical treatment, 7 and microbial remediation. 8 However, these treatment methods still have their respective shortcomings ( e.g.…”