Encapsulation of Saccharomyces boulardii into sugar pellets coated with an enteric polymer

Many current probiotic products do not optimally release enough viable cells at the site of action due to the loss of viability during manufacturing and passage through the stomach. This work aimed to formulate a modified release system that protects S. boulardii during the manufacturing process and under simulated acidic gastric conditions. S. boulardii was layered to sugar pellets, coated at 5% and 10% with the enteric polymer Eudragit^® S12.5, and encapsulated in hard gelatin capsules. During manufacturing, the main determinant of viability was the incorporation of yeast onto the sugar pellets. The viability S. boulardii in the pellets unprotected was 87.7% ± 1% after 80 min, whereas coating of unprotected pellets with 5% polymer required 54 additional min (total: 134 min) and the viability was 92.6% ± 1%, while 10% coating took 55 additional min (total: 189 min) and viability was 88.7% ± 1.8%. Notably, S. boulardii coated pellets were prepared before the recovery process. The weight variations of the pellets contained in the capsules were 0.53 ± 0.032 g and 0.55 ± 0.029 g for 5% and 10% coating, respectively. The disintegration time for each formulation was 18 min, which is below the limit of Mexican and European Pharmacopeias (30 min respectively). In the dissolution test, no release occurred under acid pH, regardless of the Eudragit percentage. In contrast, under alkaline pH conditions, polymer dissolution occurred, releasing S. boulardii 65% ± 0.46% and 68% ± 0.23% for the 5% and 10% enteric coatings, respectively, after 20 min in alkaline condition the release was 81% ± 0.48% and 87% ± 0.33% respectively. In conclusion, this modified-release system may serve as an alternative for preserving the viability of S. boulardii during gastric passage, potentially increasing the number of viable yeast cells that reach the site of action, primarily the small intestine.