Authors : Huda Khanam; Dr. Kriti Bhandari

Volume/Issue : Volume 11 - 2026, Issue 5 - May

Google Scholar : https://tinyurl.com/2wvnvbf2

Scribd : https://tinyurl.com/kfb2ztdr

DOI : https://doi.org/10.38124/ijisrt/26May280

Note : A published paper may take 4-5 working days from the publication date to appear in PlumX Metrics, Semantic Scholar, and ResearchGate.

Abstract : The human gut microbiome is an extremely multifaceted and dynamic ecosystem that includes bacteria, viruses, fungi, and archaea that interact to play fundamental roles in host physiology, metabolism, immunity, and neurodevelopment. Since its first identified in the nineteenth century by cultivation-based methods, microbiome research has expanded and is now supported by the 16S rRNA sequencing method, metagenomics, culturomics, and multi-omics platforms, which allow the researcher to gain a deeper insight into microbial diversity and functional interactions. In healthy individuals, the predominant bacterial phyla, Firmicutes, Bacteroidetes, Proteobacteria, and Actinobacteria, play a role in the regulation of metabolism, synthesis of nutrients, and intestinal integrity. The gut-brain axis (GBA) has become an important two-way communication system that connects the gastrointestinal tract with the central nervous system via the neural, endocrine, immune, and metabolic systems. Gut microbial dysbiosis has been implicated in a growing number of neurological and neurodevelopmental diseases, such as Alzheimer’s disease, Parkinson’s disease, multiple sclerosis, and autism spectrum disorder Ne.w therapeutic approaches to the microbiome, which include probiotics, prebiotics, synbiotics, psychobiotics, and fecal microbiota transplantation (FMT), show the potential to restore the microbiome, reduce inflammation, and control neurochemical signaling.. Multi-omics data integration provides a holistic system of connectivity between microbial genetic potential, real-time metabolic expression, and host phenotypes, enhancing mechanistic insights into microbiome-host interactions. Altogether, the microbiome-gut-brain axis is a paradigm shift in human health, and the gut microbiota is a key player that regulates brain activity and pathology.

Keywords : Gut Bacteria, Human Health, Neurological Disorders, FMT, Probiotics, Metabolomics.

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