Untitled

Abstract

The enteric flora comprise approximately 95% of the total number of cells in the human body and are capable of eliciting immune responses while also protecting against microbial pathogens. However, the resident bacterial flora of the gastrointestinal tract (GIT) may also be implicated in the pathogenesis of several chronic conditions such as inflammatory bowel disease (IBD). The University College Cork-based Probiotic Research Group has successfully isolated and identified lactic acid bacteria (LAB) which exhibit beneficial probiotic traits. These characteristics include the demonstration of bile tolerance; acid resistance; adherence to host epithelial tissue; and in vitro antagonism of potentially-pathogenic micro-organisms or those which have been implicated in promoting inflammation. The primary objective of this report is to describe the strategy adopted for the selection of potentially effective probiotic bacteria. The study further describes the evaluation of two members of the resulting panel of micro-organisms (Lactobacillus salivarius subsp. salivarius UCC118 and Bifidobacterium longum infantis 35624) under in vitro conditions and throughout in vivo murine and human feeding trials. Specifically, an initial feeding study completed in Balb/c mice focused upon (i) effective delivery of the probiotic micro-organisms to the GIT and evaluation of the ability of the introduced strains to survive transit through, and possibly colonise, the murine GIT; (ii) accepting the complexity of the hostile GIT and faecal environments, development of a method of enumerating the introduced bacterial strains using conventional microbiological techniques; and (iii) assessment of the effects of administered bacterial strains on the numbers of specific recoverable indigenous bacteria in the murine GIT and faeces. Additional research, exploiting the availability of murine models of inflammatory bowel disease, demonstrated the beneficial effects of administering probiotic combinations of Lactobacillus salivarius UCC118 and Bifidobacterium longum infantis 35624 in prevention of illness-related weight loss. A further ethically-approved feeding trial, successfully conducted in 80 healthy volunteers, demonstrated that yoghurt can be used as a vehicle for delivery of Lactobacillus salivarius strain UCC118 to the human GIT with considerable efficacy in influencing gut flora and colonisation.

Diversity of the genus Lactobacillus revealed by comparative genomics of five species

“…This strain was isolated from the terminal ileum of a healthy human subject undergoing reconstructive urinary tract surgery (Dunne et al, 1999). It has been extensively studied for its probiotic properties in human trials and animal models (Dunne et al, 1999(Dunne et al, , 2001McCarthy et al, 2003;Sheil et al, 2004).…”

“…This strain was isolated from the terminal ileum of a healthy human subject undergoing reconstructive urinary tract surgery (Dunne et al, 1999). It has been extensively studied for its probiotic properties in human trials and animal models (Dunne et al, 1999(Dunne et al, , 2001McCarthy et al, 2003;Sheil et al, 2004). Members of this species are commonly isolated from the oral and GI tracts of humans and other animals (Ahrne et al, 1998;Heilig et al, 2002;Molin et al, 1993;Rogosa et al, 1953).…”

Multireplicon genome architecture of Lactobacillus salivarius

“…L. salivarius subsp. salivarius strain UCC118 was isolated from the terminal ileum of a (otherwise healthy) patient undergoing urinary tract reconstructive surgery (8). This strain has been extensively studied for its probiotic properties in human trials and animal models (8)(9)(10)(11).…”

“…salivarius strain UCC118 was isolated from the terminal ileum of a (otherwise healthy) patient undergoing urinary tract reconstructive surgery (8). This strain has been extensively studied for its probiotic properties in human trials and animal models (8)(9)(10)(11). In addition, L. salivarius UCC118 produces a two-component bacteriocin Abp118 (12), which has broad spectrum activity against Gram-positive bacteria, including methicillin-resistant Staphylococcus aureus (8).…”

Probiotic and Antioxidative Properties ofL. LactisLL27 Isolated from Milk

“…the pepsin-ph experiments were done to simulate the gastric biofluid; it should be noted that the gastric biofluid has a pH ranging from 1 to 3. Probiotic bacteria need to be able to survive the passage through the stomach and also the exposure to bile in the intestine (7,14). in our work, the number of viable cells in simulated gastric juice for ll27 was higher than that reported by various researchers who proposed their own isolates as potential probiotics (2,25,55,59).…”