[Increasing evidence suggests that microbiota and especially the gut microbiota (the microbes inhabiting the gut including bacteria, archaea, viruses, and fungi) plays a key role in human physiology and pathology. Recent findings indicate how dysbiosis—an imbalance in the composition and organization of microbial populations—could severely impact the development of different medical conditions (from metabolic to mood disorders), providing new insights into the comprehension of diverse diseases, such as IBD, obesity, asthma, autism, stroke, diabetes, and cancer. Given that microbial cells in the gut outnumber host cells, microbiota influences human physiology both functionally and structurally. Microbial metabolites bridge various—even distant—areas of the organism by way of the immune and hormone system. For instance, it is now clear that the mutual interaction between the gastrointestinal tract and the brain (gut–brain axis), often involves gut microbiota, indicating that the crosstalk between the organism and its microbial residents represents a fundamental aspect of both the establishment and maintenance of healthy conditions. Moreover, it is crucial to recognize that beyond the intestinal tract, microbiota populates other host organs and tissues (e.g., skin and oral mucosa). We have edited this eBook with the aim of publishing manuscripts focusing on the impact of microbiota in the development of different diseases and their associated treatments.]

This is the first comprehensive volume to look at the importance of short-chain fatty acids in digestion, the function of the large intestine and their role in human health. Short-chain fatty acids are the major product of bacterial fermentation of dietary carbohydrates in the human and animal large intestine. They represent the major end products of digestive processes occurring in the caecum and large intestine. As such, they form an important dietary component and it is increasingly recognised that they may have a significant role in protecting against large bowel cancer and in metabolism. Prepared by an international team of contributors who are at the forefront of this area of research, this volume will be an essential source of reference for gastroenterologists, nutritionists and others active in this area.

The book provides an overview on how the gut microbiome contributes to human health. The readers will get profound knowledge on the connection between intestinal microbiota and immune defense systems. The tools of choice to study the ecology of these highly-specialized microorganism communities such as high-throughput sequencing and metagenomic mining will be presented. In addition the most common diseases associated to the composition of the gut flora are discussed in detail. The book will address researchers, clinicians and advanced students working in biomedicine, microbiology and immunology.

The composition of gut microbiota plays a critical role in maintaining the host's health, particularly in regulating immune homeostasis and the intestinal immune response. A massive effort has pointed to the importance of these interactions in various intestinal diseases like colorectal cancer (CRC), irritable bowel syndrome (IBS), and inflammatory bowel disease (IBD). Microbiome influences the formation of key components of both the innate and adaptive immune systems, while the immune system is responsible for regulating and maintaining the symbiotic relationship between the host and microbes. Currently, the crosstalk between gut flora and host immunity is not fully revealed in both homeostasis maintenance and disease development. Hence detailed mechanistic studies are needed to further explore the microbial manipulation on host immunity as well as the immune response to microbiome dysbiosis in intestinal diseases. Current evidence indicates a strong bidirectional interaction between microbiome perturbation and immune dysregulation. The aim of this Research Topic is to create a platform for the advancement of research on the causal relationship between the microbiome and immunity. Besides, we would like to define the core microbiota responsible for the initiation and progression of intestinal diseases, the molecular mechanisms of host immune-microbiome interactions, and novel gut-targeted pharmacological interventions to achieve a positive impact on intestinal disease.

The Food Forum convened a public workshop on February 22-23, 2012, to explore current and emerging knowledge of the human microbiome, its role in human health, its interaction with the diet, and the translation of new research findings into tools and products that improve the nutritional quality of the food supply. The Human Microbiome, Diet, and Health: Workshop Summary summarizes the presentations and discussions that took place during the workshop. Over the two day workshop, several themes covered included: The microbiome is integral to human physiology, health, and disease. The microbiome is arguably the most intimate connection that humans have with their external environment, mostly through diet. Given the emerging nature of research on the microbiome, some important methodology issues might still have to be resolved with respect to undersampling and a lack of causal and mechanistic studies. Dietary interventions intended to have an impact on host biology via their impact on the microbiome are being developed, and the market for these products is seeing tremendous success. However, the current regulatory framework poses challenges to industry interest and investment.

The term “immunobiotics” has been proposed to define microbial strains able to beneficially regulate the mucosal immune system. Research in immunobiotics has significantly evolved as researchers employed cutting-edge technologies to investigate the complex interactions of these beneficial microorganisms with the immune system. During the last decade, our understanding of immunobiotics-host interaction was profoundly transformed by the discovery of microbial molecules and host receptors involved in the modulation of gut associated immune system, as well as the systemic and distant mucosal immune systems. In recent years, there has been a substantial increase in the number of reports describing the beneficial effects of immunobiotics in diseases such as intestinal and respiratory infections, allergy, inflammatory bowel disease, obesity, immunosuppression, and several other immune-mediated conditions. Evidence is also emerging of immunobiotics related molecules with immunomodulatory functions leading to the production of pharmabiotics, which may positively influence human or animal health. Therefore, research in immunobiotics continue to contribute not only to food but also medical and pharmaceutical fields. The compilation of research articles included in this ebook should help reader to have an overview of the recent advances in immunobiotics.