Inhibitory Effects of Bifidobacterium longum BB536 on Harmful Intestinal Bacteria

Abstract

The inhibitory effects of human-derived Bifidobacterium longum BB536 on harmful intestinal bacteria were examined by co-cultivation of BB536 with each one of the following eight bacterial strains: Escherichia coli, Klebsiella pneumoniae, Clostridium clostridiiforme, C. perfringens, Bacteroides distasonis, B. fragilis, B. thetaiotaomicron and B. vulgatus. In comparison with the results of mono-cultivation, BB536 inhibited both the growth of these putrefactive bacteria and their production of ammonia, and decreased the pH of the culture medium by producing lactic and acetic acids. Enzymatic assays showed that in BB536 the sorts of the enzymes involved in ammonia production (urease and amino acid deaminases) were rather few and their activities were weaker than observed in the harmful bacteria, whereas the activities of enzymes involved in ammonia assimilation (glutamine synthetase, glutamate synthase and glutamate dehydrogenase) were much higher in BB536 than in the putrefactive bacteria.

In vitro investigations of the effect of probiotics and prebiotics on selected human intestinal pathogens

“…2) where these bacteria failed to proliferate at the pH environment (pH≤5.0) normally induced by bifidobacterial and lactobacilli fermentation. Similar findings have been observed for B. bifidum 1452 [19], an L. plantarum strain [22] and a bifidobacterial strain B. longum [23], where a decrease in pH during incubation time increased the antagonistic properties against E. coli , Staphylococcus aureus , Klebsiella pneumoniae , and a number of clostridia and bacteroides species, including Clostridium perfringens and Bacteroides fragilis .…”

In vitro investigations of the effect of probiotics and prebiotics on selected human intestinal pathogens

“…2) where these bacteria failed to proliferate at the pH environment (pH95.0) normally induced by bi¢dobacterial and lactobacilli fermentation. Similar ¢ndings have been observed for B. bi¢dum 1452 [19], an L. plantarum strain [22] and a bi¢dobacterial strain B. longum [23], where a decrease in pH during incubation time increased the antagonistic properties against E. coli, Staphylococcus aureus, Klebsiella pneumoniae, and a number of clostridia and bacteroides species, including Clostridium perfringens and Bacteroides fragilis.…”

Pet food and feed applications of inulin, oligofructose and other oligosaccharides

“…Detrimental influences include diarrhoea, infection, and digesta putrefaction, as well as the absorption and metabolism of mutagenic and carcinogenic chemicals (Rowland et al 1985). Conversely, beneficial bacteria bestow positive effects on the host and may inhibit the growth of harmful bacteria, including E. coli, C. perfringens, salmonellae, listeria, campylobacter, and shigellas (Gibson & Wang, 1994;Araya-Kojima et al 1995). Homma (1988) described bifidobacteria as a resistance factor in humans based on defence against pathogens, infections and reduction of serum cholesterol.…”