Chapter 1 : Introduction

Abstract:

Live microbes that when administered in adequate amounts confer a health benefit on the host are termed “probiotics”. Important contributing research includes using modern molecular methods to refine our understanding of the types and activities of microbes colonizing healthy and diseased humans; identifying the way in which microbes dynamically interact with host cells and other commensal microbes; applying functional genomics and gene array techniques to better understand the genetic and metabolic capacity of therapeutic microbes. By nature of their ability to influence the intestinal microbiota and environment, their physiological effects are often complementary to probiotic influences. Numerous are the types of health effects of probiotics and prebiotics supported by controlled (albeit some are preliminary) studies in the target host animal (humans, companion animals, or animals used in animal agriculture). The practical implications of such observations suggest the importance of testing blended strain products as they are in the final product formulation. With this caution in mind, it is of interest to note the list of health targets for the many different types of probiotics that have been tested in humans. Dissemination of such information is critical to providing a better understanding of the parameters for successful intervention for probiotics and prebiotics. Perhaps the most compelling means of probiotic function may be through interaction with host immune cells, which may occur during transit of the microbe through the sparsely colonized small intestine that is rich in immune sensing cells.