Survival of free and microencapsulated Lb. rhamnosus LC705 in simulated gastric and intestinal juice

Abstract

Breast milk is an important food for the neonates during their early months of development, primarily educating their immune system and protecting them for pathogens. The aim of this research was to investigate the probiotic properties (resistance to acid and bile salt) of free and microencapsulated Lb. rhamnosus LC705 strain isolated from mothers’ breast milk. Lb. rhamnosus LC705 was encapsulated into alginate (AL)-whey protein isolate (WPI) microspheres and morphology and particle size of the microcapsules were determined. The Viability of free and encapsulated forms in simulated gastric and intestinal juice was studied. Entrapment efficiency (emulsion method) was ~ 88%. The images of the scanning electron microscope (SEM) illustrated spherical shaped microcapsules with approximate diameters of less than 100 μm. The survival of free and microencapsulated Lb. rhamnosus LC705 was reduced to 6 and 4 log cycle in simulated gastric juice (pH 2.5, 2 h). Microencapsulated Lb. rhamnosus LC705 (D-values 27.10 min) survived better than the free cells (D-values 13.38 min) against bile salts (0.5%, 2 h). The survival of microencapsulated cells was significantly (p < 0.05) better than the free cells. Therefore microencapsulation of Lb. rhamnosus LC705 in AL–WPI containing matrix has the potential to increase the strain viability against simulated gastrointestinal conditions.