β-d-glucan as an enteric delivery vehicle for probiotics

Three strains of probiotics L. casei, L. acidophilus and B. bifidum were encapsulated in β-d-glucan matrix using freeze drying technique in order to increase survivability during their journey through GI tract. The encapsulation efficiency (%) of β-d-glucan varied significantly with Bifidobacteria showing low survival rate than Lactobacilli. SEM images revealed a partially collapsed structure with Bacterial cells distributed randomly in the matrix. Further absorption band between 1300 and 900cm^-1 in FTIR spectra shows the presence of Bacterial proteins and nucleic acids. For encapsulated β-d-glucan maximum degree of swelling was observed at pH 3 and 4, whereas when the pH value was increased to 6.5 the encapsulated β-d-glucan started their disintegration. In vitro release studies revealed that the microcapsules start to dissolve upon entry to the small intestine where it is needed most.