Properties of Lactobacillus reuteri chitosan-calcium-alginate encapsulation under simulated gastrointestinal conditions Authors Hui-Ying Huang Department of Nutrition, China Medical University, Taichung Yi-Ju Tang Department of Nutrition, China Medical University, Taichung V. An-Erl King Department of Food Science and Biotechnology, National Chung-Hsing University, Taichung, Taiwan Jen-Wei Chou Division of Gastroenterology and Hepatology, Department of Internal Medicine, China Medical University Hospital, College of Medicine, China Medical University, Taichung. Jen-Horng Tsen Department of Nutrition, China Medical University, Taichung. Keywords: Lactobacillus reuteri, Listeria monocytogenes, chitosan–calcium-alginate encapsulation, probiotic properties, simulated gastrointestinal conditions Abstract The protective effects of encapsulation on the survival of Lactobacillus reuteri and the retention of the bacterium’s probiotic properties under simulated gastrointestinal conditions were investigated. Viable counts and the remaining probiotic properties of calcium (Ca)-alginate encapsulated (A group), chitosan-Ca-alginate encapsulated (CA group), and unencapsulated, free L. reuteri (F group) were determined. Encapsulation improved the survival of L. reuteri subjected to simulated gastrointestinal conditions, with the greatest protective effect achieved in the CA group. The degree of cell membrane injury increased with increasing bile salt concentrations at constant pH, but the extent of injury was less in the encapsulated than in the free cells. Adherence rates were, in descending order: CA (0.524%) > A (0.360%) > F (0.275%). Lactobacillus reuteri cells retained their antagonistic activity toward Listeria monocytogenes even after incubation of the lactobacilli under simulated gastrointestinal conditions. Displacement of the pathogen by cells released from either of the encapsulation matrices was higher than that by free cells. The safety of L. reuteri was demonstrated in an in vitro invasion assay. [Int Microbiol 2015; 18(1):61-69]Keywords: Lactobacillus reuteri · Listeria monocytogenes · chitosan–calcium-alginate encapsulation · probiotic properties · simulated gastrointestinal conditions Author Biography Hui-Ying Huang, Department of Nutrition, China Medical University, Taichung Downloads PDF Issue Vol. 18 No. 1 (2015) Section Research Articles License Submission of a manuscript to International Microbiology implies: that the work described has not been published before, including publication in the World Wide Web (except in the form of an Abstract or as part of a published lecture, review, or thesis); that it is not under consideration for publication elsewhere; that all the coauthors have agreed to its publication. The corresponding author signs for and accepts responsability for releasing this material and will act on behalf of any and all coauthors regarding the editorial review and publication process.If an article is accepted for publication in International Microbiology, the authors (or other copyright holder) must transfer to the journal the right–not exclusive–to reproduce and distribute the article including reprints, translations, photographic reproductions, microform, electronic form (offline, online) or any other reproductions of similar nature. Nevertheless, all article in International Microbiology will be available on the Internet to any reader at no cost. The journal allows users to freely download, copy, print, distribute, search, and link to the full text of any article, provided the authorship and source of the published article is cited. The copyright owner's consent does not include copying for new works, or resale. In these cases, the specific written permission of International Microbiology must first be obtained.Authors are requested to create a link to the published article on the journal's website. The link must be accompanied by the following text: "The original publication is available on LINK at <http://www.im.microbios.org>. Please use the appropiate URL for the article in LINK. Articles disseminated via LINK are indexed, abstracted, and referenced by many abstracting and information services, bibliographic networks, subscription agencies, library networks, and consortia.