title: Microencapsulation in Alginate and Chitosan Microgels to Enhance Viability of Bifidobacterium longum for Oral Delivery.
abstract: Probiotic microorganisms are incorporated into a wide variety of foods, supplements, and pharmaceuticals to promote human health and wellness. However, maintaining bacterial cell viability during storage and gastrointestinal transit remains a challenge. Encapsulation of bifidobacteria within food-grade hydrogel particles potentially mitigates their sensitivity to environmental stresses. In this study, Bifidobacterium longum subspecies and strains were encapsulated in core-shell microgels consisting of an alginate core and a microgel shell. Encapsulated obligate anaerobes Bifidobacterium longum subsp. infantis and Bifidobacterium longum subsp. longum exhibited differences in viability in a strain-dependent manner, without a discernable relationship to subspecies lineage. This includes viability under aerobic storage conditions and modeled gastrointestinal tract conditions. Coating alginate microgels with chitosan did not improve viability compared to cells encapsulated in alginate microgels alone, suggesting that modifying the surface charge alone does not enhance delivery. Thus hydrogel beads have great potential for improving the stability and efficacy of bifidobacterial probiotics in various nutritional interventions.
authors.affiliation: Department of Food Science, University of Massachusetts Amherst, MA, USA.
authors.forename: Timothy W
authors.initials: TW
authors.lastname: Yeung
authors.affiliation: Department of Food Science, University of Massachusetts Amherst, MA, USA.
authors.forename: Elif F
authors.initials: EF
authors.lastname: Üçok
authors.affiliation: Department of Food Science, University of MassachusettsAmherst, MA, USA; Commonwealth Honors College, University of MassachusettsAmherst, MA, USA.
authors.forename: Kendra A
authors.initials: KA
authors.lastname: Tiani
authors.affiliation: Department of Food Science, University of MassachusettsAmherst, MA, USA; Center for Bioactive Delivery, Institute of Applied Life Science, University of MassachusettsAmherst, MA, USA.
authors.forename: David J
authors.initials: DJ
authors.lastname: McClements
authors.affiliation: Department of Food Science, University of MassachusettsAmherst, MA, USA; Center for Bioactive Delivery, Institute of Applied Life Science, University of MassachusettsAmherst, MA, USA; Center for Microbiome Research, University of Massachusetts Medical SchoolWorcester, MA, USA.
authors.forename: David A
authors.initials: DA
authors.lastname: Sela
keywords: bifidobacteria; microencapsulation; oral delivery; probiotics; simulated digestion