Sources of Probiotics and Their Benefits
Understanding probiotics
Probiotics are food supplements and live, nonpathogenic microbial feeds that benefit the host by changing the microbial balance, according to the Food Agricultural Organization and World Health Organization. They can improve the host's health by enhancing the gut barrier integrity and function, regulating the gut-associated lymphoid immune system, and modulating the signaling pathways for immunity.
However, probiotics can confer beneficial health effects only if taken in adequate amounts. Probiotic bacteria usually belong to the Lactobacillus and Bifidobacterium genera, but other microorganisms such as bacterial spores and yeast can also exhibit probiotic properties. They are different from other bacteria such that they normally inhabit the human intestinal tract, can survive the extreme conditions in the upper digestive tract, can produce antimicrobial substances, can colonize the human intestinal cell line, and are safe for human consumption.
Probiotic bacteria can improve gut health through several mechanisms. They reduce the pro-inflammatory cytokines and increase the antibody, IgA, to modulate the intestinal immune function. They also maintain the gut epithelial cells by enhancing the barrier function, increasing mucin production, and improving cell survival. The anti-infective defenses of Lactobacilli are not yet fully understood, but they can block pathogenic bacteria by decreasing luminal pH, producing antibacterial bacteriocins, and reducing pathogen binding to the gut epithelia. They can also assist the digestion of foods into usable nutrients. Research has also shown that probiotic bacteria can affect the nervous system function through the gut-microbiota-brain axis. They can reduce visceral hypersensitivity and stress response, as well as induce cannabinoid receptors and mu-opioid receptors on the epithelial cells.
Benefits of probiotics
Aside from their positive effects on the host's general well-being, promising research suggests that probiotics also have significant effects on the treatment of intestinal disorders. For instance, Lactobacillus acidophilus LA-5 and Bifidobacterium animalis ssp. lactis, BB-12 were found to reduce diarrhea and constipation in elderly patients. Other species like Lactobacillus casei Shirota, found in the fermented mild milk called Yakult, have beneficial effects on short bowel syndrome and chronic constipation. Further, Lactobacillus paracasei ssp. paracasei and Lactobacillus casei 431 have been found effective in the treatment of diarrheal cases in infants and young children.
These examples are claimed benefits from the studies on the commercial application of isolated probiotic species. Their beneficial effects are also case- and strain-specific. As such, more studies are needed to make the human intervention studies more conclusive.
Common sources of probiotics
Yogurt is one of the most common sources consisting of various bacterial strains like Lactobacillus bulgaricus and Streptococcus thermophilus. Yogurt is fortified with strains often shown to have clinical research on beneficial health effects. Strains used are selected also based on their survival in the product throughout its shelf life and during their transit to the stomach and the rest of the GI tract, so they can reach the distal tract where they mostly exert their function.
Fermented food and beverages are another source of potentially beneficial bacteria resulting from the process of itself. This is an increasingly growing food trend with more new types coming to market regularly. However, not all fermented foods contain probiotics. For instance, kimchi, kombucha, miso, and pickles contain live cultures of bacteria, but they don't have standardized levels of identifiable beneficial bacteria. Performing a microbiome analysis using DNA sequencing can help provide better clarity on the microorganism environment.
Consumers also take probiotics in the form as dietary supplements, usually in powders, liquids, and capsule forms. Probiotic dietary supplements typically are tested to confirm viable cell count of bacteria as well as to confirm the identification of the strains present. Today, customers have many options to choose from single strain supplements to blends of several organisms.
New sources of probiotics
New methods have already been developed to fortify encapsulated probiotic bacteria in unfermented foods such as milk, juices, cereals, nutrition bars, smoothies, and infant formula. Several methods such as emulsion, extrusion, spray drying, and fluidized bed can incorporate probiotics efficiently. These methods ensure the protection of probiotics from extreme gut conditions and their adherence and colonization of the human GI tract for maximum health benefits. Cell encapsulation improves the survival of the probiotic bacteria in food matrices and turns non-dairy and unfermented food into carriers for probiotics. Bacillus coagulans and Bacillus subtilis are popularly used due to their survivability during processing and product shelf life.
Further, vegan consumers increased the demand for products with health benefits, including probiotic products. Fermented and non-fermented beverages are the common vegan probiotic carriers. However, some issues still need to be addressed in the development of vegan probiotic products. The survival of the strains varies depending on the food matrix and processing. The addition of probiotics affects the color, acidity, and palatability of vegan food. Lastly, the probiotic strains are isolated from non-vegetable matrices, which may compromise the products' vegan status.
Testing Probiotics
As we learned, many probiotic products are foods, feeds, beverages, or supplements that are fortified with specific strains and dosages. To confirm product label claims, samples are tested for identification as well as enumeration in order to meet defined product specifications. Analyzing for target probiotic organisms can be a challenging task. With the variety of strains, complex product matrices, and the differences in optimal growth and survival conditions for each organism, there are no one-size-fits-all methods. Be sure to work with your third party lab to determine the most appropriate and scientifically valid method for your needs. Fermented foods and beverages pose challenges for label claims as microorganism growth can fluctuate from batch to batch. Unique microbiome analysis using DNA sequencing cane be helpful during product development stage to identify any potential adjustments in processing to yield a more preferred product.
Eurofins boasts an entire team of experience scientists dedicated to using the latest methods and technology to enumerate and identify probiotic and other potentially beneficial bacteria in your products. Let us be an extension of your company and help with any method development and validation needs as well.
