title: Stability of lactobacilli encapsulated in various microbial polymers.
abstract: Various microbial polymers, namely xanthan gum, gellan gum, pullulan gum and jamilan, were tested as a suitable encapsulating material for Lactobacillus plantarum CRL 1815 and Lactobacillus rhamnosus ATCC 53103. Resulting capsules were also studied for their pH and simulated gastrointestinal conditions tolerance. The morphology of the microcapsules was studied using scanning electron microscopy. pH tolerance was tested at pH 2.0, 3.5, 5.0 and 6.5 over a 6h incubation period. Simulated gastrointestinal conditions were assayed with simulated gastric and pancreatic juices and simulated bile over a 24h incubation period. Suspensions of probiotic organisms were used as a control. The results from encapsulation with microbial polymers indicate that mixtures of 1% xanthan gum with 0.75% gellan gum and 1% jamilan with 1% gellan gum were the most suitable for microencapsulation. Results for the pH tolerance tests showed no improvement in the viability of cells in relation to the control, except for pH 2.0 where lactobacilli encapsulated in xanthan:gellan gum (1%:0.75%) prolonged their viability by 6h exposure. Xanthan:gellan gum (1%:0.75%) was the most effective of the encapsulating materials tested in protecting L. plantarum and L. rhamnosus against simulated bile, improving its viability in 1-2 logCFU when compared with control. The results of this study suggest that microbial polymers are an interesting source of encapsulating material that should be taken into account for prospective studies of probiotic encapsulation for oral delivery applications.
authors.affiliation: Departamento de Microbiología, Facultad de Farmacia, Universidad de Granada, Campus de Cartuja s/n, 18071 Granada, Spain. jimepra@ugr.es
authors.forename: María Luján
authors.initials: ML
authors.lastname: Jiménez-Pranteda
authors.forename: Denis
authors.initials: D
authors.lastname: Poncelet
authors.forename: María Elena
authors.initials: ME
authors.lastname: Náder-Macías
authors.forename: Antonio
authors.initials: A
authors.lastname: Arcos
authors.forename: Margarita
authors.initials: M
authors.lastname: Aguilera
authors.forename: Mercedes
authors.initials: M
authors.lastname: Monteoliva-Sánchez
authors.forename: Alberto
authors.initials: A
authors.lastname: Ramos-Cormenzana
mesh_terms: D001646:Bile / Q000502:physiology; D001704:Biopolymers / Q000737:chemistry; D002214:Capsules; D041981:Gastrointestinal Tract / Q000502:physiology; D006863:Hydrogen-Ion Concentration; D007778:Lactobacillus; D048191:Lactiplantibacillus plantarum; D052201:Lacticaseibacillus rhamnosus; D011135:Polysaccharides, Bacterial / Q000737:chemistry*; D019936:Probiotics / Q000008:administration & dosage*
chemical_list: D001704:Biopolymers; D002214:Capsules; D011135:Polysaccharides, Bacterial; C048288:gellan gum; C002563:xanthan gum