Fig. 2
Growth and survival of bacteria post encapsulation. a After encapsulation of overnight pre-cultures of bacteria or yeast at fairly low bacterial density (2 × 106 CFU/mL), the CS capsules containing the bacteria were incubated under standard bacterial growth conditions (appropriate medium and temperature with agitation) for 1 or 2 days to allow the encapsulated bacteria to multiply. Using the alamarBlue® assay, the metabolic activity of the bacteria was measured 1 day and 2 days after encapsulation and the Relative Light Units (RLU) recorded from the alamarBlue® assay plotted for L. casei (b) and for E. coli K12 (c) Shown is the average of two experiments and the standard deviation for both bacteria. The ability of the bacteria to grow in the capsules was also visually evident when comparing the L. casei capsules immediately after encapsulation (d) with the L. casei containing capsules 24 h later (e) under the microscope (× 100 magnification)