Probiotic Attributes of Lactobacillus rhamnosus of Dairy Origin and Effectiveness of Almond in Stimulation of its Growth in vitro

Abstract

Three strains of Lactobacillus rhamnosus of dairy origin and Lactobacillus rhamnosus GG (LGG) as a reference organism, were compared for their probiotic attributes viz., acid tolerance, bile salt tolerance, cell surface hydrophobicity and antimicrobial activity. Among the different organisms, Lactobacillus rhamnosus NCDC 17 was found to be the best strain in acid tolerance and antimicrobial activity and exhibited good bile salt tolerance and cell surface hydrophobicity. Prebiotic effectiveness of almond for stimulation of growth of L. rhamnosus NCDC 17 and LGG was also investigated in vitro. Almond supplementation to basal medium at the level of 2% (w/ v) exhibited stimulatory effect on proliferation of both the strains. However, LGG fared comparatively better than L. rhamnosus NCDC 17 as indicated by an increase in viable counts to the extent of 1.3-1.5 log cycles as compared to an increment of around 0.9-1.1 log cycles in case of L. rhamnosus NCDC 17 after 12 h of incubation. Inulin was not found to support the growth of any of the L. rhamnosus strains. Almond may serve as a natural source of prebiotic which may be used in combination with health promoting probiotic lactobacilli in synbiotic formulations for a wide range of health attributes.