Much like humans, probiotics do not all look the same! Some are long and skinny, some are round and bumpy, and some look like they have little feathers. Probiotics can clump together, or swim around alone. Some even have shells, or cocoon-like structures! These structures can be filmy, granulated, or even “sticky.” More specifically, these protective coverings are called extracellular polymeric substances, or in some cases exopolysaccharide shells (both referred to using the acronym “EPS”).
You may be asking, why should I care?
Well, these extracellular shells are also known as plasma when they protect your blood cells, or bone minerals when they protect your bone tissue—both very important functions for you to stay alive and unhurt. Additionally, these “shells” are very advantageous to the probiotics colonizing your gut, and therefore to you, who benefits from having a balanced system of microflora. In this blog, we will take you through the structure and function of this special trait, and how probiotics which have it can be advantageous to you.
The scientific term for the protective structure around a cell is made up of the prefix “extra-,“ which means outer, “-poly-,” which means multiple, and “-meric,” which means similar units. Thus, one can infer that it describes an outer covering made up of many tiny units! This “matrix” is usually formed by deposits on the surface of a cell. There are products which you take with your probiotics that can provide these deposits from an outside source, often hydrogenated fats, but there are also strains which produce coatings naturally.
Microencapsulation technology is used for a wide array of products, most commonly pharmaceuticals. Manufactured microcapsules can protect vitamins from chemical changes due to light, oxygen, carbon dioxide or nitrogen, prevent evaporation, and mask taste. They can prevent leaching of pesticides, create an adhesive surface, or create a new medium of application (powder instead of liquid, for example).
Bacteria which form a natural extracellular substance include Lactococcus lactis (found in dairy products), Zooglea (found in wastewater), Bacillus licheniformis (found on bird feathers and in soil), and Aspergillus niger (black mold). You may encounter L. lactis every day, if you regularly enjoy some cheese on your sandwich or a cold glass of milk! This particular strain has an exopolysaccharide shell that contributes a slightly gelatinous texture to milk products such as yogurt and cheese.
Probiotic strains such as Lactobacillus paracasei (LP-DG, the strain used in Innovia Probiotics), Bifidobacterium longum, Bifidobacterium animalis and Lactobacillus rhamnosus are species which also form a natural extracellular substance, and can have a beneficial effect in your gut because of it.
Strains such as the ones listed above have better functionality when it comes to adhesion and bacterial settlements, whether on a piece of fruit or in the digestive tract. Their matrix coatings can protect from the harsh acidic environment of the stomach, and allow them to survive in larger numbers. Did you know that 99.99% of food-delivered probiotics will die on the journey between your mouth and your gut? Fecal recovery samples (yes, poop!) are an important way to tell if a probiotic is able to effectively colonize the gastrointestinal tract. Probiotic strains which contain EPS have more of a presence in fecal recovery samples, because they are protected and allowed to pass through the digestive system without much damage.
Now, we’re going to take a journey through the body to see how an EPS affects the path of probiotics through your digestive tract. The probiotic enters your mouth via powder, pill, or liquid. It travels through your throat and down the esophagus, through the stomach, and into your colon. Once through the stomach, probiotics with an extracellular substance still intact will adhere much more easily than those without. Then, they can start colonizing and balancing the population in your gut for better digestion!
We already discussed the presence of the extracellular matrix around your blood and bone cells, but it shows up other places in your body’s complex system as well. Extracellular structures can equip the body with a means to draw heavy metals and other substances out of the body, because of its adhesive properties. Furthermore, the EPS can connect all sorts of cells together, and can be instrumental for cell growth or healing wounds. There was even a relatively recent study on the ability of a facial cream containing exopolysaccharides to reduce the particle adherence of several pollutants, with positive results.
Beyond the human body, the EPS structure can have industrial significance in multiple ways. Extracellular deposits, depending on the type, can aid in the cleansing of toxic substances, including oil spills. In an experimental measure during the Deepwater Horizon oil spill, bacteria with EPS were used to dissolve the oil and create collections of it on the water’s surface that made cleanup easier. Their rapid growth proved beneficial, and of potential future use. Additionally, the ability of the extracellular matrix to pick up heavy metals may prove important in developing antipollution projects, such as diminished groundwater contamination.
Now that you have a little more information regarding the structure of probiotics, keep extracellular polymeric substances in mind when you are looking for a strain that’s right for you! Remember, probiotic strains with the EPS, including LP-DG¬¬ ®, can be especially effective at staying present in your gut. If you are looking for long-term gut balance, this trait could prove especially important for you. Remember, balance begins within!