Oxidation and degradation of graphitic materials by naphthalene-degrading bacteria

Abstract

Nowadays, biologically oxidizing graphitic materials is of great importance for practical applications as an eco-friendly and low-cost method. In this work, a bacterial strain is isolated from the contaminated soil in a graphite mine and its ability to oxidize graphite, graphene oxide (GO) and reduced graphene oxide (RGO) is confirmed. After being cultivated with bacteria, graphite is inhomogeneously oxidized, and moreover oxidized sheets exfoliated from graphite are detected in the medium. RGO shows a higher degree of oxidation compared to graphite owing to more original defects, while GO breaks into small pieces and becomes full of holes. Both the holes in GO and the exfoliated sheets from graphite caused by bacteria have a size of below 1 μm, in agreement with the size of bacterial cells. Besides, the preliminary mechanism of the bacterial oxidation is explored, suggesting that the contact between bacterial cells and materials promotes the oxidation of graphitic materials. The ability of naphthalene-degrading bacteria to oxidize and degrade the graphitic materials shows the potential for producing GO in an eco-friendly way and degrading carbon nanomaterials in the environment.

Biological interactions of carbon-based nanomaterials: From coronation to degradation

“…We and others have documented the degradation of single- and multi-walled CNTs and GO by HRP and H 2 O 2 [141,143–146]. Moreover, lignin peroxidase produced by white rot fungus also has the capacity to induce oxidative biodegradation of fullerenes, SWCNTs, and graphene nanoribbons [147–149] while recent studies have demonstrated biodegradation of MWCNTs and GO by various bacteria [150,151]. …”

Bio‐nano interface and environment: A critical review

“…Similarly, several studies have shown the biodegradation of different CNMs by bacterial communities [70,71]. Liu et al [70] suggested that direct contact between bacterial cells and materials promotes the oxidation of carbonaceous material. Interestingly, a fungi-bacteria soil microcosm rapidly mineralized a CNM.…”

Prokaryotic Community Composition and Extracellular Polymeric Substances Affect Soil Microaggregation in Carbonate Containing Semiarid Grasslands

“…Additionally, a strong effect of the graphitic C content on the prokaryotic community composition was found, indicating a potential interaction between the prokaryotes and the graphite. Only recently it has been recognized that graphite might be utilized by soil microbes (Liu et al, 2015;Hemingway et al, 2018), but little is known about the exact role of graphite on overall soil microbial life. As stated in previous publications (e.g., Ding et al, 2013;Babin et al, 2014;Fierer, 2017), factors affecting prokaryotic community composition in soil can be manifold.…”