The Effect of Drinking Yoghurt Containing Free and Microencapsulated Probiotic Bacteria on Changes of the Population of These Bacteria in the Digestive System

Background & Aims: Probiotic bacteria have beneficial effects on host's health. However, one of the most important reasons which affect the probiotic activity of a microorganism is its survival during the gut transit. Microencapsulation techniques could be applied to bacteria to improve this parameter. Methods: In this study, feces of ۶۰ healthy volunteers were analyzed during ۲۸-day test period to assess changes of probiotic bacteria. Participants were divided into equal ۴ groups; group ۱ did not receive probiotic drinking yoghurt (control); group ۲ received probiotic drinking yoghurt containing free Lactobacillus acidophilus and Bifidobacterium animalis, subspecies lactis; group ۳ recieved the same strains microencapsulated with sodium alginate/resistant starch; and group ۴ received probiotic drinking yoghurt containing microencapsulated probiotic bacteria with sodium alginate/chitosan. Results: A significant increase was recorded in the population of lactobacilli and bifidobacteria in the feces of participant in three groups at the end of the treatment compared with control group (P < ۰.۰۵ for all), confirming the ability of the ۲ strains to colonize the human gut, either in a gastroprotected form or not. Participants treated with the microencapsulated bacteria reported more viability than those received not encapsulated strains. Feces of group ۳ that received drinking yoghurt containing encapsulated probiotic bacteria with alginate/resistant starch had higher amount of probiotic bacterial populations, ۱.۳ ± ۰.۲۶ × ۱۰۷ and ۲.۴ ± ۰.۳۷ × ۱۰۹ cfu/g Lactobacillus acidophilus and Bifidobacterium animalis subs lactis, respectively. Conclusion:Consumption of the drinking yoghurts containing probiotic bacteria increased the Lactobacillus acidophilus and Bifidobacterium animalis, subspecies lactis, contents of the feces and encapsulation process improved stability of probiotic bacteria

Keywords:

Fecal analysis , Probiotic bacteria , Drinking yoghurt , Encapsulation