Development of probiotic tablets using microparticles: viability studies and stability studies

Alternative vectors to deliver viable cells of probiotics, to those conferring limited resistance to gastrointestinal conditions, still need to be sought. Therefore the main goal of the study was to develop tablets able to protect entrapped probiotic bacteria from gastric acidity, thus providing an easily manufacturing scale-up dosage form to deliver probiotics to the vicinity of the human colon. Whey protein concentrate microparticles with Lactobacillus paracasei L26 were produced by spray-drying and incorporated in tablets with cellulose acetate phthalate and sodium croscarmellose. The viability of L. paracasei L.26 throughout tableting as well as its gastric resistance and release from the tablets were evaluated. Storage stability of L. paracasei L26 tablets was also performed by evaluation of viable cells throughout 60 days at 23°C and 33% relative humidity. A decrease of approximately one logarithmic cycle was observed after the acid stage and the release of L. paracasei L26 from the tablets occurred only after 4 h in the conditions tested. Microencapsulated L. paracasei L26 in tablets revealed some susceptibility to the storage conditions tested since the number of viable cells decreased 2 log cycles after 60 days of storage. However, the viability of L. paracasei L26 after 45 days of storage did not reveal significant susceptibility upon exposure to simulated gastrointestinal conditions. The developed probiotic tablets revealed to be potential vectors for delivering viable cells of L. paracasei L26 and probably other probiotics to persons/patients who might benefit from probiotic therapy.The authors gratefully acknowledge Formulab and DSM for providing the whey protein concentrate and probiotic strain, respectively. This work was funded by FEDER under the Operational Program for Competitiveness Factors— COMPETE and by National funds via FCT—Fundação para a Ciência e a Tecnologia within the framework of project PROBIOCAPS—references PTDC/AGR-ALI/71051/2006 andFCOMP-01-0124-FEDER-008792,andthroughindividual research grants (SFRH/BPD/73781/2010, SFRH/BD/77647/ 2011 and SFRH/BPD/65410/2009) by FCT under QREN– POPH funds, co-financed by the European Social Fund and Portuguese National Funds from MCTES.publishe