Release studies of Lactobacillus casei strain Shirota from chitosan-coated alginate-starch microcapsules in ex vivo porcine gastrointestinal contents

AIMS: To investigate the release characteristics of Lactobacillus casei strain Shirota (LCS) from chitosan-coated alginate-starch (CCAS) capsule in different regions of ex vivo porcine gastrointestinal (GI) contents. METHODS AND RESULTS: A 0.1 g of CCAS encapsulated bacteria (containing c. 10(8) CFU of LCS) were incubated in different sections of ex vivo porcine GI contents (10 ml) anaerobically at 37 degrees C. Samples were taken from different GI contents at different time intervals (up to 24 h) and estimated for the release of LCS from capsules. There was almost a complete release (1.1 x 10(8) CFU) of LCS from capsules within 8 h of incubation in ileal contents, while it took nearly 12 h to release the completely encapsulated bacteria in colon content under similar conditions. There was only a partial release of encapsulated LCS, incubated in duodenal and jejunal contents, while there was no significant (P > 0.05) release of encapsulated bacteria in gastric contents even after 24 h of incubation. CONCLUSIONS: The capsules were able to release viable probiotic cells completely in ex vivo porcine ileal and colon contents. SIGNIFICANCE AND IMPACT OF THE STUDY: CCAS capsule can be an effective way of protecting probiotic bacteria from adverse gastric conditions and delivering viable bacteria to the host intestinal systems.