The effect of prebiotics on production of antimicrobial compounds, resistance to growth at low pH and in the presence of bile, and adhesion of probiotic cells to intestinal mucus

Abstract

Aims: Screening of five bile salt‐resistant and low pH‐tolerant lactic acid bacteria for inhibitory activity against lactic acid bacteria and bacterial strains isolated from the faeces of children with HIV/AIDS. Determining the effect of prebiotics and soy milk‐base on cell viability and adhesion of cells to intestinal mucus. Methods and Results: Lactobacillus plantarum 423, Lactobacillus casei LHS, Lactobacillus salivarius 241, Lactobacillus curvatus DF 38 and Pediococcus pentosaceus 34 produced the highest level of antimicrobial activity (12 800 AU ml−1) when grown in MRS broth supplemented with 2% (m/v) dextrose. Growth in the presence of Raftilose®Synergy1, Raftilose®L95 and Raftiline®GR did not lead to increased levels of antimicrobial activity. Cells grown in the presence of Raftilose®Synergy1 took longer to adhere to intestinal mucus, whilst cells grown in the absence of prebiotics showed a linear rate of binding. Conclusions: A broad range of gram‐positive and gram‐negative bacteria were inhibited. Dextrose stimulated the production of antimicrobial compounds. Adhesion to intestinal mucus did not increase with the addition of prebiotics. Significance and Impact of the Study: The strains may be incorporated in food supplements for HIV/AIDS patients suffering from gastro‐intestinal disorders.

Identification, Characterization, and Recombinant Expression of Epidermicin NI01, a Novel Unmodified Bacteriocin Produced by Staphylococcus epidermidis That Displays Potent Activity against Staphylococci

“…The location of the tryptophan has also been shown to affect the extent to which penetration occurs (6,9,32). In the synthetic peptide cecropin A (1)(2)(3)(4)(5)(6)(7)(8) -magainin 2 (1)(2)(3)(4)(5)(6)(7)(8)(9)(10)(11)(12) (consisting of residues 1 to 8 of cecropin A and residues 1 to 12 o f magainin 2), tryptophan has been proposed as a potential anchor site on the membrane (37). Epidermicin, aureocin A53, and lacticin Z are highly cationic with a net charge of ϩ8, and lacticin Q has a net charge of ϩ6.…”

“…These results provide evidence for the proteinaceous nature of epidermicin. As the peptide was not affected by ␣-amylase or lipase, it probably does not contain polysaccharide or lipid moieties (4,39).…”

Evaluation of lactic acid bacteria from kefir, molasses and olive brine as possible probiotics based on physiological properties

“…Although the role of bacteriocins and their significance in controlling the proliferation of pathogenic bacteria in the intestinal tract is questionable (Brink et al, 2006), recent reports on bacteriocins active against Gram-negative bacteria (Ivanova et al, 1998;Messi et al, 2001;Caridi, 2002;Dicks, 2005a, 2005b) placed a renewed interest in these peptides and their interaction with intestinal pathogens.…”

Isolation, Identification and Screening of Potential Probiotic Bacteria in Milk from South African Saanen Goats

“…Images of adhering bacterial cells were captured using a high-performance CCD camera, mounted on a Nikon Eclipse E400 epi-fluorescence microscope, equipped with a x60/1.4 Dic H oil objective and filters. Sections of ileum suspended in MRS-cysHCL broth not inoculated with any bacteria served as controls (Brink et al, 2006).…”