The main goal of this research was to examine the viability of five strains of encapsulated lactic acid
bacteria [LAB] (Lactobacillus plantarum ATCC14917, Lactobacillus casei NCAIM B01137, Lactobacillus
rhamnosus ISO7, Bifidobacterium breve ISO8 and Leuconostoc mesenteroides subsp. mesenteroides DSM
20343) in model solutions designed to simulate the acidity, bile salt, and phenol concentrations identified within
the human gastrointestinal system. The capsules were formulated using sodium alginate and kappa (k)-
carrageenan. The application of sodium alginate and k-carrageenan has been shown to provide ideal properties
for the encapsulation of live bacteria strains. All bacteria grew well in the presence of 0.1 and 0.5% bile salt
during incubation to 6 hours except Leuconostoc mesenteroides subsp. mesenteroides DSM 20343 was sensitive
to bile salt concentrations. At pH 7.0 (control), survival of LAB in MRS medium remained stable after 6 hours
of incubation at 37 regardless of whether they were encapsulated or non-encapsulated. At a pH of 3, the
number of encapsulated LAB exhibited a minor reduction after 6 hours of incubation, whereas the free cells
showed a one-log decrease under comparable conditions. The survival of all LAB strains decreased by
increasing the salt concentration during the incubation time up to 6 hours. All tested LAB strains showed
resistance to Gentamycin, Kanamycin, Erythromycin and Lincomycin. Research indicated that capsules made
from sodium alginate and k-carrageenan effectively safeguarded the tested strains against gastric acid, leading to
a significant release of viable bacteria in the intestine. |
