Carboxymethyl konjac glucomannan-chitosan complex nanogels stabilized emulsions incorporated into alginate as microcapsule matrix for intestinal-targeted delivery of probiotics: In vivo and in vitro studies

In this study, we developed a novel delivery system using carboxymethyl konjac glucomannan-chitosan (CMKGM-CS) nanogels stabilized single and double emulsion incorporated into alginate hydrogel as microcapsule matrix for intestinal-targeted delivery of probiotics. Through in vitro experiments, it was demonstrated that alginate hydrogel provided favorable biocompatible growth conditions for the proliferation of Lactobacillus reuteri (LR). The alginate hydrogel containing single (ASE) or double emulsions (ACG) enhanced the resistance of LR to various adverse environments. Simulated gastrointestinal digestion experiments revealed that the survivability of LR in free, CON, ASE and ACG group decreased by 6.45 log CFU/g, 4.21 log CFU/g, 1.26 log CFU/g and 0.65 log CFU/g, respectively. In vivo studies conducted in mice showed that ACG maintained its integrity during passage through the stomach and released the probiotics in the targeted intestinal area, whereas the pure alginate hydrogels (CON) were prematurely released in the gastrointestinal tract. Moreover, the viable counts of ACG in different intestinal segments (jejunum, ileum, cecum, and colon) were increased by 1.11, 1.42, 1.68, and 1.89 log CFU/g, respectively, after 72 h of oral administration compared to the CON group. This research contributed valuable insights into the development of an effective microbial delivery system with potential applications in the biopharmaceutical and food industries.