Recovery of a Probiotic Organism from Human Faeces after Oral Dosing. In: Gibson SAW, editor. Human Health. London: Springer; 1994. pp. 119-43. [DOI: 10.1007/978-1-4471-3443-5_8]

Development of a Dairy-Free Fermented Oat-Based Beverage With Enhanced Probiotic and Bioactive Properties

Lactobacillus fermentum PC1 with proven probiotic properties was used to ferment oats with added honey to develop a probiotic beverage with enhanced bioactive ingredients. The viable Lactobacilli were enumerated during the fermentation and storage at 4°C, as well as after exposure to simulated gastrointestinal tract conditions. Good survival was noted both during storage as well as when exposed to the in vitro digestive tract conditions. Comparative analysis of the antioxidant activity, total phenolic content, and phenolic composition indicated fermentation improved the total antioxidant capacity and phenolic acid concentration. An increase of more than 50% of gallic acid, catechin, vanillic acid, caffeic acid, p-coumaric acid, and ferulic acid was observed in the methanol extracts. Moreover, no significant decrease in the β-glucan content was noted during fermentation and storage. In conclusion, this fermented product has a great potential as a functional food with enhanced probiotic survival and increased bioactive ingredients.

Adjuvant properties and colonization potential of adhering and non-adhering Lactobacillus spp following oral administration to mice

This study aimed to determine whether adhesive strains of Lactobacillus possessed an increased ability to colonize the gastrointestinal tract and to examine the adjuvant capacities of these strains for the 50000 molecular-mass fragment C of tetanus toxin (TTFC) following oral administration. The three strains used in this study showed different patterns of adhesion to tissue from all regions of the gastrointestinal tract, with two strains adhering in high numbers and one strain showing negligible association with all tissue types. The colonization patterns in the gastrointestinal tract of C57BL/6 mice following oro-gastric dosing was also monitored, and it was found that adhesive Lactobacillus strains could be detected for at least 24 h, in association with either fecal material and/or with gastrointestinal tissue or contents. In addition, mice were given an oro-gastric dose of the lactobacilli (5 x 10(8) colony forming units) with TTFC (10 and 50 micro g), and the serum-specific IgM and IgG antibody responses monitored in serum. The adhesive strains, which persisted within the gastrointestinal tract for at least 24 h, showed enhanced antigen-specific serum IgG and IgM antibody responses in comparison to a non-adhesive strain that failed to be detected in the gastrointestinal tract. Adhesion to the gastrointestinal tract is a factor affecting the capacity of lactobacilli to persist within the gastrointestinal tract and to act as an adjuvant for orally administered antigen.

Colonization by lactobacilli of piglet small intestinal mucus

The colonization potential of lactobacilli was investigated using small intestinal mucus extracts from 35-d-old pigs. Mucus-secreting tissue from the small intestine of piglets was gently rinsed to remove contents and then shaken in buffer to release mucus from the surface. Numbers of lactobacilli in different portions of the small intestine of 35-d-old pigs were enumerated. Also, mucus isolated from the small intestine of pigs was investigated for its capacity to support the growth of lactobacilli. Results indicated that Lactobacillus spp. inhabit the mucus layer of the small intestine and can grow and adhere to ileal mucus. From adhesion studies of Lactobacillus fermentum 104R to mucus analysed by Scatchard plot, it is suggested that an associating system showing positive cooperativity is involved. Proteinaceous compounds(s) involved in the adhesion to mucus were detected in the spent culture fluid from the growth of strain 104R. Studies are continuing in order to identify and characterize the adhesion-promoting protein(s). From the data, it is proposed that lactobacilli colonize the mucus layer of the small intestine of pigs.

A simulation of microbial competition in the human colonic ecosystem

Many investigations of the interactions of microbial competitors in the gastrointestinal tract used continuous-flow anaerobic cultures. The simulation reported here was a deterministic 11-compartment model coded by using the C programming language and based on parameters from published in vitro studies and assumptions were data were unavailable. The resource compartments were glucose, lactose and sucrose, starch, sorbose, and serine. Six microbial competitors included indigenous nonpathogenic colonizers of the human gastrointestinal tract (Escherichia coli, Enterobacter aerogenes, Bacteroids ovatus, Fusobacterium varium, and Enterococcus faecalis) and the potential human enteropathogen Salmonella typhimurium. Flows of carbon from the resources to the microbes were modified by resource and space controls. Partitioning of resources to the competitors that could utilize them was calculated at each iteration on the basis of availability of all resources by feeding preference functions. Resources did not accumulate during iterations of the model. The results of the computer simulation of microbial competition model and for various modifications of the model. The results were based on few measured parameters but may be useful in the design of user-friendly software to aid researchers in defining and manipulating the microbial ecology of colonic ecosystems as relates to food-borne disease.

Probiotic treatment of small intestinal bacterial overgrowth by Lactobacillus fermentum KLD

The principle of using harmless bacteria for conquering pathogens has been used for many years. It has been used prophylactically against travellers' diarrhoea and for protection of recurrent pseudomembranous colitis. The aim of this study was to treat a chronic infectious condition, small intestinal bacterial overgrowth, by oral administration of a certain strain of Lactobacillus. 17 patients with long-standing bacterial overgrowth of the small intestine were included. The study was designed as a double-blind cross-over, where the patients were their own controls. The study was divided into 4 parts. (A) For the first 2 weeks placebo was given b.i.d. (B) For the next 4 weeks patients received either placebo or 10(10) Lactobacillus fermentum KLD b.i.d. (C) A wash-out period of 4 weeks followed. (D) Finally, for the second 4 week treatment period patients were crossed over to receive either lactobacilli or placebo. A hydrogen breath test with 50 g glucose was performed at the start and at the end of each period. Symptom scores were recorded on the last week of each period. The study was completed by 14 patients. Lactobacillus treatment showed no significant difference compared to placebo with respect to the results of the hydrogen breath test: 29 (3-95) vs 14 (3-129) ppm, (median and 10th and 90th percentiles), stool frequency: 14 (8-40) vs 12 (7-31) defecations/week. or symptom score: 12 (5-46) vs 17 (6-42) scores/week). High numbers of L. fermentum KLD in faecal samples were only seen in 2 patients. In conclusion, dosage with L. fermentum KLD in this study did not significantly alter the parameters investigated.