Prebiotics Promoting Growth and Retention to Probiotics

Prebiotics Promoting Growth and Retention to Probiotics

Prebiotics Promoting Growth and Retention To Probiotics

Process/flow diagram/hazards

Sources of Probiotics

Probiotics can be found in certain foods and dietary supplements. Examples of foods containing probiotics are yogurt; fermented and unfermented milk, including kefir; miso; tempeh; some juices; and soy beverages. Probiotics are also found in a wide variety of supplements in the form of capsules, tablets, and powders made for ingestion. Both probiotic foods and supplements contain bacteria that may have been present in the product originally or added during processing or preparation (Wright & McCrea, 2000: 121).

A number of bacteria and viruses are used as probiotics. These include Lactobacillus, Bifidobacterium, Streptococcus thermophilus, Propionibacterum, Bacillus, Enterococcus, and Escherichia coli. Within each group, there are many different species and strains. Some yeasts, such as Saccharomyces boulardii, are also commonly used as probiotics.

It is important to note that when it comes to the use of probiotics, no two strains or species are alike. Consequently, the effect of each probiotic depends on the particular strain used.

Harmful and Helpful Intestinal Microbiota

To understand how probiotics may be used to promote better health, registered dietitians must first understand how probiotics work in the gut (Lockie et al. 2006: 29). The GI tract contains more than 500 different species of bacteria, many of which are pathogenic. Pathogenic bacteria outnumber beneficial bacteria by a factor of 100 pathogenic cells to 10 protective cells. The beneficial bacteria that exist in people's bodies, especially in the GI tract, are extremely important for proper development of the immune system, in protecting the body against pathogenic bacteria or other microorganisms that may cause disease, and to ensure proper digestion and absorption of food and nutrients.

About 60 to 80 percent of immune system components can be found in the gut, so there is strong evidence supporting the link between intestinal health and immune system function (Knight & Kotschevar, 2000: 87). Any time there is a reduction in the number of beneficial bacteria a person has or an increase in pathogenic bacteria, there is a greater chance that the pathogenic bacteria may assert themselves and cause illness or disease. Each person's mix of GI flora varies, but experts agree that interactions between microorganisms and the person they inhabit may be extremely important to a person's health and well-being.

Mechanism of Action

Probiotics ultimately work in the GI lumen and the mucosal barrier by promoting immune responses and by affecting the enteric nervous system. A number of probiotics work specifically at the GI lumen. Some produce certain antimicrobial products called bacteriocins, which inhibit the growth of pathogenic bacteria. Others may reduce the pH of the environment in the gut lumen to levels undesirable for growth. Yet other probiotics may compete for binding sites at the GI lumen, promoting “colonization resistance.” (Barrientos & Dolan, 2006: 12).

Probiotics can work at the mucosal barrier as well. Some enhance the production and secretion of mucins from epithelial cells. This mucosal layer may prevent the binding of pathogens and may help ...