The human gut microbiota, or the “virtual organ”, plays a crucial role in defining the state of human health and disease. In combination with graphene oxide (GO) it holds potential as a new territory for drug delivery. However, the potential interactions between GO nanocarriers and gut bacteria are poorly understood. Understanding these impacts could generate new insights and opportunities for future medical application in treating human diseases. Now, reporting in Nanotechnology, researchers have systematically investigated the interaction of GO with five of the most common gut bacteria and uncovered some beneficial synergies.

The disruption of homeostasis in the gut microbiota has been known to play a crucial role in the development of multiple health conditions including colon cancer, inflammatory bowel disease and non-alcoholic fatty liver disease. The unique properties of GO, such as its high specific surface area, mechanical strength and easy functionality, make it attractive in biomedical applications to combat this. Recognizing this, a research team led by Weiyue Feng at the Institute of High Energy Physics, Chinese Academy of Sciences in China, investigated the interactions between GO and five common human gut bacterial strains, including B. adolescentis, L. acidophilus, E. faecalis, E. coli and S. aureus.

Antagonistic effects of B. adolescentis 

The GO sheets were biocompatible and had no significant influence on the morphology and membrane integrity of the gut bacteria in normal bacterial cell media. They were able to form effective, anaerobic membrane scaffolds to promote bacterial adhesion and proliferation, particularly for B. adolescentis. Moreover, when pathogens E. coli and S. aureus were treated with GO co-cultured B. adolescentis, GO showed significant enhancement of B. adolescentis proliferation and antagonistic effects against E. coli and S. aureus.

Probiotic optimization 

The optimization of the composition of probiotics (e.g. B. adolescentis, Lactobacilli, Bifidobacteria) in the intestinal microflora may positively influence the gut flora to inhibit pathogenic colonization, affect the mucosal barrier and stimulate the immune system to protect human health.

This study indicates that GO sheets are beneficial in biomedical applications including drug carriers for intestinal systems, and application in gut microbiota-related drug discovery and therapeutic strategies to fight against human diseases. (nanotechweb.org)