Efficient protection of microorganisms for delivery to the intestinal tract by cellulose sulphate encapsulation

Abstract

Background Gut microbiota in humans and animals play an important role in health, aiding in digestion, regulation of the immune system and protection against pathogens. Changes or imbalances in the gut microbiota (dysbiosis) have been linked to a variety of local and systemic diseases, and there is growing evidence that restoring the balance of the microbiota by delivery of probiotic microorganisms can improve health. However, orally delivered probiotic microorganisms must survive transit through lethal highly acid conditions of the stomach and bile salts in the small intestine. Current methods to protect probiotic microorganisms are still not effective enough. Results We have developed a cell encapsulation technology based on the natural polymer, cellulose sulphate (CS), that protects members of the microbiota from stomach acid and bile. Here we show that six commonly used probiotic strains (5 bacteria and 1 yeast) can be encapsulated within CS microspheres. These encapsulated strains survive low pH in vitro for at least 4 h without appreciable loss in viability as compared to their respective non-encapsulated counterparts. They also survive subsequent exposure to bile. The CS microspheres can be digested by cellulase at concentrations found in the human intestine, indicating one mechanism of release. Studies in mice that were fed CS encapsulated autofluorescing, commensal E. coli demonstrated release and colonization of the intestinal tract. Conclusion Taken together, the data suggests that CS microencapsulation can protect bacteria and yeasts from viability losses due to stomach acid, allowing the use of lower oral doses of probiotics and microbiota, whilst ensuring good intestinal delivery and release.

Controlled Nutrient Delivery through a pH-Responsive Wood Vehicle

“…Clearly, the probiotic-loaded microchannels can be sealed by the combination of the stability of the Ca-cross-linked alginate at acidic pH with the rolled structure of the wood scroll, which helps to improve the probiotic survival rate. In fact, the survival rate within the wood scrolls is not only superior to some other encapsulating structures such as particles (60–79%) and core–shell capsules (47–90%) from widely used polymer and natural materials but also exceeds some commercial probiotic products that come in pill (44.60 ± 1.51%), powder (83.65 ± 0.58%), and capsule forms (92.36 ± 1.20%) (Figure S14, SI). − …”

Intestinal Engineered Probiotics as Living Therapeutics: Chassis Selection, Colonization Enhancement, Gene Circuit Design, and Biocontainment

“…The coating protects the probiotics, enhances their colonization, allows for near-quantitative coating, and exhibits natural pharmaceutical activity, enabling the encapsulated probiotics to exhibit synergistic therapeutic effects in mice . Commonly used coating materials include dextran, polysaccharide chitosan, polysaccharide alginate, cellulose sulfate, and silk fibroin, etc., which have been reportedly applied to probiotics such as C. butyricum , L. rhamnosus , L. acidophilus , L. johnsonii , L. casei , B. coagulans , B. infantis , and EcN. ,− …”

Probiotics in Fish Nutrition—Long-Standing Household Remedy or Native Nutraceuticals?

“…Furthermore, several teleosts are agastric (approximately 20% of the species) and do not have acidic digestion. Experimentally, artificial gastric juices stimulate the passage of the stomach [165,166,179,180]. As a rule of thumb, the lower the actual pH, the more sophisticated the strategies of administration required, most of which are adopted from application to higher vertebrates.…”

“…As a rule of thumb, the lower the actual pH, the more sophisticated the strategies of administration required, most of which are adopted from application to higher vertebrates. These include delivery systems such as microencapsulation in cellulose sulfate or calcium alginate [180], legume protein encapsulation [181], hydrogels [182], and coated mucoadhesive films [183] or bioencapsulation in live biological vectors [184]. The probiotic should be retained within the delivery system, and the system should be stable until it is exposed to a specific set of environmental conditions (most importantly pH, bile salts, and enzyme activities).…”