Viability of <i>Bifidobacterium bifidum</i> and <i>Escherichia coli</i> in Versus Prebiotic Effects of Jerusalem Artichoke (<i>Helianthus tuberosus</i>)

Abstract

Background: In this study, in vitro prebiotic effects of Jerusalem artichoke poly-fructans on the survivability and activity of Bifidobacterium bifidum, Escherichia coli were investigated and compared with HP-Inulin (a high molecular-weight fraction of chicory-derived inulin). Objectives: The prebiotic potential of poly-fructans extracted from native Jerusalem artichoke tubers on the survivability of B. bifidum and E. coli was evaluated in this study. Methods: In this experimental study, 24 treatments divided to 2 groups (Extracted poly-fructose from Jerusalem artichoke tubers and standard inulin) randomly. The turbidity and pH variations during 48 hours incubation were determined using final concentrations of each group (0.5%, 1%, 2% and 3% (w/v)). The data were analyzed by MINITAB 14 and MSTATC statistical software, one way ANOVA and Duncan’s test. Results: This study suggests that Jerusalem artichoke tuber fructooligosaccharides (JA-Fr) had the potential to be used as a prebiotic component. The growth of B. bifidum improved significantly in the presence of Jerusalem artichoke fructans compared to the control. There was no significant differences (P < 0.05) in Bifidobacterium population in different concentrations of Jerusalem artichoke poly-fructans, but the population was significantly higher than the count in the presence of HP-inulin. The pH decreased in both media during 48 hours incubation time. Specific rate of growth and doubling time determined for E. coli demonstrated that the efficacy of various carbon sources in stimulating bacterial growth were influenced by the concentration and DP (degree of polymerization) of fructan chains in the media. Conclusions: Jerusalem artichoke fructooligosaccharides can provide the greater stability of probiotics and acid production, so it can be considered as a potential source of high-yielding oligosaccharide for commercial prebiotic production to develop food industry and improve host health.