Behaviour of the pharmaceutical probiotic preparation VSL#3 in human ileostomy effluent containing its own natural elements.

The pharmaceutical probiotic VSL#3 (300 billion cfu/g lactic acid bacteria & bifidobacteria) was inoculated into human ileostomy effluent (HIE) to assess its behaviour vs the ileo-caecal tract. Separately, yogurt bacteria (yog) and bifidobacteria (Bif) present in VSL#3 were also inoculated into HIE. During 37 degrees C incubation (anaerobic condition) at zero, six and 24 hours, both cell growth in control HIE and indigenous Bif growth in HIE+yog were observed. Cells remained viable and metabolically active as shown by the increase in L(+) lactic acid in HIE+VSL#3 and HIE+yog and the pH decreased (approx. 5.5 compared with the 6.2 of control HIE). Total SCFA Short Chain Fatty Acids decreased in HIE+yog and HIE+VSL#3 at 6h and in all cultures at 24h; butyric acid decreased in HIE+Bif and HIE+VSL#3. Generally in vivo the bacteria remain in the ileo-caecal tract no longer than six h, therefore VSL#3 bacteria seem able to pass this barrier viably, colonizing the large bowel.

Rapid enzymatic method for biotyping and control of lactic acid bacteria used in the production of yogurt and some cheeses.

Determination of enzymatic patterns of 30 strains of Streptococcus thermophilus and 18 strains of Lactobacillus delbrueckii subsp. bulgaricus with a rapid APIZYM method was carried out. Alkaline and acid phosphatase, naphthol-AS-BI-phosphohydrolase, 10 esterases, 20 glycosidases, 61 peptidases and 2 proteases (trypsin and chymotrypsin) were included. The strains investigated were isolated from yogurt and from different starters used for different Italian cheeses. For S. thermophilus, all strains were positive for 3 glycosidases, 4 monopeptidases, 9 dipeptidases, 1 tripeptidase and all were negative for 2 esterases; 9 glycosidases; 8 peptidases and trypsin. For L. delbrueckii subsp. bulgaricus it was observed that all strains were positive for 2 esterases; 2 glycosidases; 11 monopeptidases, 9 dipeptidases, 2 tripeptidases and 1 tetrapeptidase and all were negative for alkaline-phosphatase; 3 esterases, 7 glycosidases, 5 monopeptidases, 2 dipeptidases. The defined enzymatic pattern of starter cultures can be used for predicting their suitability for dairy fermentations and for monitoring their stability as well as for typing.

Enhancement of host resistance against Salmonella typhimurium infection by a diet supplemented with yogurt.

The effect of a diet supplemented with yogurt containing live lactobacilli (LAB) - Lactobacillus bulgaricus and Streptococcus thermophilus - on the response of inbred mice to infection with Salmonella typhimurium was elaborated. The results of our experiments were consistent with the hypothesis that modifications of the microflora influence the adherence of S. typhimurium to intestinal mucosa, the natural antibacterial activity of the Peyer's patches lymphocytes, the accumulation of the macrophages in the liver, the proliferative responses of the splenocytes. The relationship between modifications of the immune response following ingestion of yogurt with live LAB and increased defense mechanisms was confirmed by the bacterial counts in livers and spleens and by the reduced mortality to S. typhimurium infection.

Adherence of specific yogurt micro-organisms to human peripheral blood lymphocytes.

Yogurt lactic-acid-bacteria (LAB) consisting of Lactobacillus bulgaricus and Streptococcus thermophilus were evaluated for their capacity to bind to human peripheral blood lymphocytes (PBL). These micro-organisms adhere to human T lymphocytes, and bind to B lymphocytes, in high and low frequencies, respectively. In addition, a quantitative analysis of LAB binding to PBL was carried out using the same parameters previously applied to a Salmonella model. The effect of yogurt LAB on the natural anti-bacterial activity exerted by PBL was examined. Lymphocyte pretreatment with bacteria did not affect such functions. These findings are discussed in the light of the well known ability of yogurt LAB to modulate the immune response.

Enhancement of immune response of murine Peyer's patches by a diet supplemented with yogurt.

The first line of defense against pathogens that enter the host by the oral route involves the Peyer's Patches (PP). For centuries many populations of the mediterranean basin have empirically administered soured milk (yogurt) to prevent and treat diarrhoea and entero-colitis. Recent reports have offered evidence in favour of a possible influence of yogurt on the host's immunocompetence. Scope of the present study was to evaluate the influence of a diet supplemented with yogurt on the PP from BALB/c mice. The results reported here suggest that yogurt feeding potentiates the host's cell-mediated immune response by increasing the percentage of B lymphocytes and the PHA and LPS-induced proliferative responses of PP cell suspensions.