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PubMed2005

Probiotics that modify disease risk.

Probiotics are defined as live bacterial preparations with clinically documented health effects in humans. Probiotics have specific properties and targets in the human intestinal tract and intestinal microbiota. Each probiotic strain, independent of its genus and species is unique and, thus, the properties and the human health effects of each strain have to be assessed in a case-by-case manner. Understanding the mechanisms by which probiotics influence the normal intestinal microbiota and counteract aberrancies in microbiota would facilitate the use of probiotics for both dietary management and reduction in risk of specific diseases. Development of intestinal microbiota is an important factor affecting the health of the newborn. Recent studies suggest that specific bacterial components, especially the bifidobacteria, have a key impact on development of a healthy balanced infant microbiota. The composition of infant and child intestinal microbiota may become aberrant and thus influence the development of diarrheal, inflammatory, and allergic diseases. Based on this understanding, positive health effects of probiotics have been reported in the management of diarrheal, inflammatory, and allergic diseases in infants. Most recently, a reduction in risk of atopic diseases followed early administration of specific probiotics.

Bacteria↗

PubMed2004

The effects of supplementation of humate and probiotic on egg production and quality parameters during the late laying period in hens.

This study was designed to investigate whether inclusions of humate and probiotic into diets of hens during the late laying period increases egg production and improves egg quality. Hisex Brown layers (n = 300), 54 wk of age, were fed a control diet, 0.1% humate, 0.2% humate, 0.1% probiotic, or 0.2% probiotic for 75 d. Active ingredients of humate and probiotic were polymeric polyhydroxy acids (humic, fulvic, ulmic, and humatomelanic acids) and bacterial cultures (Lactobacillus, Bifidobacterium, Streptococcus, and Enterococcus spp.), respectively. Egg production and feed intake were measured daily, and egg weight was measured biweekly. Also, a sample of 12 eggs from each group was collected randomly to determine egg quality every 25 d. The data were analyzed as repeated measures with time as subplot. There were no effects of dietary treatments on feed intake and egg weight. Egg production for hens supplemented with humate and probiotic was not different but was greater than for control hens. Egg production increased linearly and mortality and feed conversion efficiency (weight of feed/weight of eggs) decreased linearly with increasing levels of supplemental humate and probiotic. There were no effects of treatments on egg quality. In conclusion, supplementation of humate and probiotic during the late laying period increased egg production, reduced mortality, and improved feed conversion efficiency but did not improve egg quality.

Animal Nutritional Physiological Phenomena↗

PubMed2006

Investigating the effects of commercial probiotics on broiler chick quality and production efficiency.

A study was undertaken to test the effect of 2 commercially available probiotics on the production efficiency of broiler chickens hatched from the same breeder flock at 3 different ages (28, 43, and 57 wk). At each of the 3 breeder flock ages, 1,600 broiler chickens were hatched and randomly allocated to 1 of 4 treatments: 1) no probiotics (control), 2) probiotic 1 administered in the drinking water, 3) probiotic 1 administered as a spray, and 4) probiotic 2 administered in the feed. A coccidiostat was included in the feed, but no other antimicrobial agents were given. Broilers were then reared on straw litter in identical floor pens for a period of 6 wk. There were no significant differences in broiler BW, feed conversion, or mortality between the probiotic treatments and the control group in any of the trials. The 43-wk-old breeder flock had the highest fertility and hatchability and the lowest percentage of chicks culled at hatching. Throughout the broiler production period, the broilers from the 43- and 57-wk-old breeder flocks had higher BW and weight gains than the broilers produced at 28 wk of breeder flock age. Broiler feed conversion over the 6-wk production period decreased as the breeder flock aged. Probiotics had no effect on chick quality or production efficiency in broilers produced by the breeder flock ages examined.

Aging↗

PubMed2006

Upregulation of oxidative burst and degranulation in chicken heterophils stimulated with probiotic bacteria.

The immune system of neonatal chicks is functionally immature during the first week of life. Researchers have previously demonstrated that the avian humoral response can be increased with probiotics. Although the humoral response provides the chick with an effective mechanism to combat pathogens, sufficient antibody titers are not attained until 7 to 10 d postinfection. However, the innate immune system (i.e., heterophils) can respond much more quickly to pathogens. The objective of this study was to determine whether probiotic bacteria can also upregulate heterophil function. Heterophils were isolated from the peripheral blood of neonatal chickens by using a discontinuous density gradient. Oxidative burst and degranulation are bactericidal mechanisms used by heterophils to kill pathogens and were used in this study as indicators of heterophil function. We found that each of the 10 "generally recognized as safe" probiotic isolates (designated G1 to G11) tested in vitro were capable of increasing (P < 0.05) heterophil oxidative burst and degranulation when compared with unstimulated controls. Bacillus subtilis (G3), Lactococcus lactis lactis (G6), and Lactobacillus acidophilus (G8) isolates were determined to elicit the greatest heterophil response in vitro and were subsequently fed to chicks. Phosphate-buffered saline or 1 of these 3 probiotic isolates (approximately 2.5 x 10(8) cfu/chick; 50 chicks/treatment) resuspended in PBS was administered by oral gavage on the day of hatch. Heterophils were isolated from chicks from each of these 4 treatment groups 24 h posttreatment. Significant increases in heterophil degranulation and oxidative burst were observed with the G3-, G6-, and G8-treated chicks when compared with heterophils isolated from birds with no probiotic treatment. These data suggest that probiotic bacteria can significantly improve heterophil oxidative burst and degranulation in broilers. To our knowledge, this is the first study demonstrating a relationship between probiotics and avian heterophil function.

Animals↗

PubMed2006

Probiotics in the treatment of inflammatory bowel disease.

The demonstration that immune and epithelial cells can discriminate between different microbial species has extended our understanding of the actions of probiotics beyond simple antimicrobial concepts. Several probiotic mechanisms of action, relative to inflammatory bowel disease, have been elucidated: (1) competitive exclusion, whereby probiotics compete with microbial pathogens; (2) immunomodulation and/or stimulation of an immune response; (3) antimicrobial activity and suppression of pathogen growth; (4) enhancement of barrier activity; and (5) induction of T cell apoptosis. The unraveling of these mechanisms of action has led to new support for the use of probiotics in the management of clinical inflammatory bowel disease. While level 1 evidence now supports the therapeutic use of some probiotics in the maintenance treatment of pouchitis, only level 2 and 3 evidence are currently available in support of the use of probiotics in the treatment of ulcerative colitis and Crohn's disease. Nevertheless, one significant and consistent finding has emerged over the course of research in the past year: not all probiotic bacteria have similar therapeutic effects. Rigorously designed, controlled clinical trials, to investigate the unresolved issues related to efficacy, dose, duration of use, single or multistrain formulation, and the concomitant use of prebiotics, synbiotics or antibiotics, are vital.

Colitis, Ulcerative↗

PubMed2006

Probiotics and chronic disease.

In today's climate, changed lifestyles and the increased use of antibiotics are significant factors that affect the preservation of a healthy intestinal microflora. The concept of probiotics is to restore and maintain a microflora advantageous to the human body. Probiotics are found in a number of fermented dairy products, infant formula, and dietary supplements. Basic research on probiotics has suggested several modes of action beneficial for the human body and clinical research has proven its preventive and curative features in different intestinal and extraintestinal diseases. Chronic diseases cause considerable disablement in patients and represent a substantial economic burden on healthcare resources. Research has demonstrated a crucial role of nutrition in the prevention of chronic disease. Thus, positive, strain-specific effects of probiotics have been shown in diarrheal diseases, inflammatory bowel diseases, irritable bowel syndrome, and Helicobacter pylori-induced gastritis, and in atopic diseases and in the prevention of cancer. As the majority of probiotics naturally inhabit the human intestinal microflora, their use has been regarded as very safe. However, in view of the range of potential benefits on health that might be achieved by the use of some probiotic bacteria, major and thorough evaluation is still necessary. In conclusion, probiotics act as an adjuvant in the prevention and treatment of a wide variety of chronic diseases.

Chronic Disease↗

PubMed2001

Probiotics in the treatment and prevention of acute infectious diarrhea in infants and children: a systematic review of published randomized, double-blind, placebo-controlled trials.

BACKGROUND: This review was designed to assess the evidence from randomized controlled trials on effects of probiotics in the treatment and prevention of acute infectious diarrhea in infants and children. METHODS: A systematic review of published, randomized, double-blind, placebo-controlled trials on probiotics in the treatment or prevention of acute diarrhea defined as >3 loose or watery stools per 24 hours in infants and children. RESULTS: The use of probiotics as compared with placebo was associated with a significantly reduced risk of diarrhea lasting >3 days. The pooled estimate risk was 0.43 (95% CI, 0.34-0.53) with a fixed-effect model, and remained significant in a random-effect model (0.40; 95% CI, 0.28-0.57). Only Lactobacillus GG showed a consistent effect. Probiotics significantly reduced the duration of diarrhea when compared with placebo, particularly in rotaviral gastroenteritis-the pooled, weighted, mean difference (WMD) assuming the random-effect model was -20.1 hours (95% CI, -26.1 to -14.2) and -24.8 (95% CI, -31.8 to -17.9) respectively. A meta-analysis of the prevention studies was not feasible because of significant clinical and statistical heterogeneity. CONCLUSIONS: There is evidence of a clinically significant benefit of probiotics in the treatment of acute infectious diarrhea in infants and children, particularly in rotaviral gastroenteritis. Lactobacillus GG showed the most consistent effect, although other probiotic strains may also be effective. Further research is needed. Clinical and statistical heterogeneity of the prophylactic interventions preclude drawing firm conclusions about the efficacy of probiotics in preventing acute gastroenteritis.

Acute Disease↗

PubMed2003

The effect of antibiotic and probiotic combination therapy on secondary pancreatic infections and oxidative stress parameters in experimental acute necrotizing pancreatitis.

INTRODUCTION: Ciprofloxacin and meropenem have effects on intestinal bacteria that are responsible for pancreatic infection, and on the basis of recent data it has been argued that probiotics, especially those used in the food industry, could improve efforts to prevent and treat secondary pancreatic infections by inhibiting bacterial translocation. AIMS: To evaluate the effects of probiotic treatment alone or in combination with early administration of two different antibiotics on serum amylase, pancreatic histopathology, bacterial translocation, and oxidative markers. METHODOLOGY: Acute pancreatitis was induced in rats with 3% sodium taurocholate (1 mL/kg intraductally), except in group VI (sham group). After the stabilization period, the rats were divided into seven groups (n = 20) randomly. At hour 6 after injection, group I rats received probiotic Saccharomyces boulardii (25 mg/d orally q.d.), group II received meropenem (60 mg/kg intraperitoneally b.i.d.), group III received ciprofloxacin (40 mg/kg intraperitoneally b.i.d.), group IV received the same dose of probiotic plus meropenem, and group V received probiotic plus ciprofloxacin. Treatment was not given to group VI (sham group) and group VII (pancreatitis group). At hour 48 after induction, specimens were collected. RESULTS AND CONCLUSION: Although histopathologic scores in treatment groups were found to be lower than in group VII, the difference was statistically significant only in group V (p < 0.001). In evaluation of oxidative stress, we found that MDA levels decreased and SOD levels increased in treatment groups in comparison with levels in group VII. Probiotic treatment alone reduced bacterial translocation. Probiotic-antibiotic combination therapy was shown to improve histopathologic scores and oxidative parameters.

Analysis of Variance↗

PubMed2003

Probiotic mixture decreases DNA adduct formation in colonic epithelium induced by the food mutagen 2-amino-9H-pyrido[2,3-b]indole in a human-flora associated mouse model.

Consumption of probiotic bacteria such as bifidobacteria has been shown to reduce the risk of colon cancer in animal models. However, the composition and metabolic activities of the intestinal flora of experimental animals are significantly different from those of humans. The aim of the study was to examine whether the probiotic mixture, which consisted of Streptococcus faecalis, Clostridium butyricum and Bacillus mesentericus, could decrease DNA adduct formation induced by 2-amino-9H-pyrido[2,3-b]indole (2-amino-alpha-carboline; AAC) in the colonic epithelium of a human-flora-associated (HFA) mouse model. Ten HFA mice were divided into a control group (n=4) and a probiotic group (n=6). The control group was administered AAC for 3 days and sacrificed 24 h after the last dose. The probiotic group was administered the probiotic mixture for 2 weeks prior to the administration of AAC. Analysis of DNA adducts with the 32P-high-performance liquid chromatography method was performed on stomach, jejunum and colonic epithelium, representing direct exposure sites of AAC, and colon wall, liver and kidney, representing indirect exposure sites. The mean level of the DNA adducts in the colonic epithelium of the probiotic group was significantly lower than that of control group, while the mean levels at the other sites did not differ significantly between the groups. The results indicated that the probiotic mixture could decrease the DNA adduct formation in the colonic epithelium induced by AAC.

Animals↗

PubMed2005

Probiotics: a complementary approach in the treatment and prevention of pediatric atopic disease.

PURPOSE OF REVIEW: The goal of this article is to review recent primary research and developments in the area of probiotics and pediatric atopic disease. RECENT FINDINGS: Research developments in probiotics summarized in this article include the following: (1) the role of probiotics in primary prevention of atopic disease, (2) the effect of probiotics on cytokines involved in the allergic immune response, (3) the long-term effects of peri-natal probiotic use and (4) the relationship between the gut microflora and atopic dermatitis. SUMMARY: Probiotics continue to be an area of active investigation as our understanding evolves of the gut microbiota's role in the altered immune response of atopic patients. Physicians should be aware of these developments as probiotics may be an important complementary approach in the treatment and the natural and long-term course of various pediatric diseases. This article summarizes the research conducted over the past 10 years with a primary focus on the literature published since January 2003.

Child↗

PubMed2006

Clinical efficacy of probiotics: review of the evidence with focus on children.

Probiotics are marketed in several countries and widely used by pediatric health care providers. Although probiotics can be helpful for specific disorders, they have been broadly prescribed for disorders without clear evidence to support their use. Furthermore, in certain specific conditions, probiotics cause clinical deterioration. This report is a review and evaluation of the evidence or lack thereof to support a beneficial effect of probiotic agents in a variety of pediatric conditions and to review the safety and potential adverse events that may be encountered when using probiotics. It is also important to emphasize that probiotics are highly heterogeneous with differences in composition, biological activity, and dose among the different probiotic preparations.

Adult↗

PubMed2005

Probiotic supplementation improves tolerance to Helicobacter pylori eradication therapy--a placebo-controlled, double-blind randomized pilot study.

BACKGROUND: H. pylori is the major cause of chronic gastritis, and a risk factor for peptic ulcer and gastric cancer. AIM: To investigate the effect of probiotic supplementation on the tolerance and efficacy of H. pylori eradication treatment in a randomized, double-blind, placebo-controlled trial. METHODS: A total of 338 volunteers were screened for H. pylori infection. The eligibility criteria were met by 47 subjects whose H. pylori infection was verified at the outset and re-evaluated after the treatment by the 13C-urea breath test and by enzyme immunoassay serology. The subjects were randomized to receive probiotic therapy (Lactobacillus rhamnosus GG, L. rhamnosusLC705, Bifidobacterium breve Bb99 and Propionibacterium freudenreichii ssp. shermanii JS) or a placebo during H. pylori eradication and for 3 weeks following the treatment, and recorded their daily symptoms in a standardized diary. RESULTS: When the frequencies of new or aggravated symptoms were evaluated, no significant differences were found between the two groups for individual symptoms. However, the probiotic group showed less treatment-related symptoms as measured by the total symptom score change (P = 0.038) throughout the H. pylori eradication therapy in contrast to the placebo group. The H. pylori eradication rate was non-significantly higher in the group receiving probiotic therapy (91% vs. 79%, P = 0.42). In this group the recovery of probiotic bacteria in the faeces increased significantly (P < 0.001). CONCLUSIONS: In this pilot study, probiotic supplementation did not diminish significantly the frequency of new or aggravated symptoms during H. pylori eradication. However, our data suggest an improved tolerance to the eradication treatment when total symptom severity was taken into account. Furthermore, the results show that probiotic bacteria are able to survive in the gastrointestinal tract despite the intensive antimicrobial therapy.

Adult↗

PubMed2005

A probiotic mixture alleviates symptoms in irritable bowel syndrome patients: a controlled 6-month intervention.

BACKGROUND: Irritable bowel syndrome is a gastrointestinal disorder of unknown aetiology. The effect of probiotics in this syndrome remains unclear. AIM: To investigate whether a probiotic mixture containing Lactobacillus rhamnosus GG, L. rhamnosus LC705, Bifidobacterium breve Bb99 and Propionibacterium freudenreichii ssp. shermanii JS is effective in alleviating irritable bowel syndrome symptoms. METHODS: A total of 103 patients fulfilling the Rome I or II criteria took part in this 6-month, randomized, double-blind placebo-controlled trial. The patients received a probiotic capsule or a placebo capsule daily. Gastrointestinal symptoms and bowel habits were recorded. RESULTS: At the end the total symptom score (abdominal pain + distension + flatulence + borborygmi) was 7.7 (95% CI: -13.9 to -1.6) points lower in the probiotic group (P = 0.015). This represents a median reduction of 42% in the symptom score of the probiotic group compared with 6% in the placebo group. In individual symptoms, borborygmi was milder in the probiotic group (P = 0.008), and for the rest of the symptoms there was a non-significant trend. CONCLUSIONS: The results indicate that this probiotic mixture is effective in alleviating irritable bowel syndrome symptoms. Considering the high prevalence of irritable bowel syndrome and the lack of effective therapies, even a slight reduction in symptoms could have positive public health consequences.

Adult↗

PubMed2007

Meta-analysis: the effect of supplementation with probiotics on eradication rates and adverse events during Helicobacter pylori eradication therapy.

BACKGROUND: Recent evidence found probiotics could inhibit Helicobacter pylori colonization from both in vitro and in vivo studies. AIM: To systematically evaluate whether adding probiotics to anti-H. pylori regimens could improve eradication rates and reduce side effects during anti-H. pylori treatment. METHODS: Eligible articles were identified by searches of electronic databases. We included all randomized trials comparing probiotics supplementation to placebo or no treatment during anti-H. pylori regimens. Statistical analysis was performed with Review Manager 4.2.8. Subanalysis/Sensitivity analysis was also performed. RESULTS: We identified 14 randomized trials (n = 1671). Pooled H. pylori eradication rates were 83.6% (95% CI = 80.5-86.7%) and 74.8% (95% CI = 71.1-78.5%) for patients with or without probiotics by intention-to-treat analysis, respectively, the odds ratio (OR) was 1.84 (95% CI = 1.34-2.54); the occurrence of total side effects were 24.7% (95% CI = 20.0-29.4%) and 38.5% (95% CI = 33.0-44.1%) for groups with or without probiotics, especially for diarrhoea, the summary OR was 0.44 (95% CI = 0.30-0.66). CONCLUSIONS: Our review suggests that supplementation with probiotics could be effective in increasing eradication rates of anti-H. pylori therapy, and could be considered helpful for patients with eradication failure. Furthermore, probiotics show a positive impact on H. pylori therapy-related side effects.

Anti-Bacterial Agents↗

PubMed2005

Clinical effects of probiotics are associated with increased interferon-gamma responses in very young children with atopic dermatitis.

BACKGROUND: We recently demonstrated that administration of probiotics resulted in significant clinical improvement in very young children with moderate-to-severe atopic dermatitis (AD). The purpose of this study was to determine the underlying immunological effects that are associated with these apparent clinical benefits. METHODS: Peripheral blood mononuclear cells (PBMC) were isolated from children (n = 53) at baseline and at the end of an 8-week supplementation period during which they received a probiotic (Lactobacillus fermentum PCCtrade mark) (n = 26) or a placebo (n = 27). A further sample was collected at 16 weeks (8 weeks after ceasing the supplement). Cytokine (IL-5, IL-6, IL-10, IL-13, IFN-gamma and TNF-alpha) responses to allergens (egg ovalbumin (OVA), beta lactoglobulin (BLG), house dust mite (HDM)), vaccines (tetanus toxoid (TT)), diphtheria toxoid (DT)), intestinal flora (heat-killed Lactobacillus (HKLB)), heat-killed Staphylococcus aureus (HKSA), Staphylococcus aureus enterotoxin B (SEB) and mitogen (phytohaemaglutinin (PHA)) were compared. RESULTS: The administration of probiotics was associated with a significant increase in T-helper type 1(Th1-type) cytokine IFN-gamma responses to PHA and SEB at the end of the supplementation period (week 8: P = 0.004 and 0.046) as well as 8 weeks after ceasing supplementation (week 16: P = 0.005 and 0.021) relative to baseline levels of response. No significant changes were seen in the placebo group. The increase in IFN-gamma responses to SEB was directly proportional to the decrease in the severity of AD (r = -0.445, P = 0.026) over the intervention period. At the end of the supplementation period (week 8) children receiving probiotics showed significantly higher TNF-alpha responses to HKLB (P = 0.018) and HKSA (P = 0.011) but this was no longer evident when supplementation ceased (week 16). Although IL-13 responses to OVA were significantly reduced in children receiving probiotics after 8 weeks (P = 0.008), there were no other effects on allergen-specific responses, and this effect was not sustained after ceasing supplementation (week 16). There were no effects on vaccine-specific responses, or on responses to any of the stimuli assessed. CONCLUSION: The improvement in AD severity with probiotic treatment was associated with significant increases in the capacity for Th1 IFN-gamma responses and altered responses to skin and enteric flora. This effect was still evident 2 months after the supplementation was ceased. The lack of consistent effects on allergen-specific responses suggests that the effects of probiotics may be mediated through other independent pathways, which need to be explored further.

Allergens↗

PubMed2006

The role of probiotics in the management of allergic disease.

Probiotics have recently been advocated for the prevention and treatment of allergic disease (AD). In clinical practice they are increasingly being used for these purposes. Here we review the evidence base for the use of probiotics in the management of AD. We find support for their use in the treatment of childhood eczema, but the clinical significance of any treatment effect is uncertain. There is also evidence to support the use of probiotics in the prevention of childhood eczema. However the available evidence suggests that probiotics are not an effective treatment for allergic airway diseases. Probiotics may be more effective when used early in life, and they may have a particular role in gastrointestinal AD. The relative efficacy of different probiotic strains in the management of AD is not well established, and further work is needed to establish their mechanisms of action. In summary probiotics are likely to play a part in the management of childhood eczema in the future, and further studies are warranted to precisely define their role.

Asthma↗

PubMed2006

Effects of probiotic supplementation for the first 6 months of life on allergen- and vaccine-specific immune responses.

BACKGROUND: A reduction in microbial burden during infancy when allergen-specific memory is evolving has become a prominent explanation for the allergy epidemic. OBJECTIVE: We sought to determine whether probiotic dietary supplementation in the first 6 months of life could modify allergen- and vaccine-specific immune responses. METHODS: Two hundred and thirty-one pregnant women with a history of allergic disease and positive allergen skin prick test (SPT) were recruited into a randomized-controlled trial. The infants received either a probiotic (3 x 10(9)Lactobacillus acidophilus LAVRI-A1; Probiomics) or placebo (maltodextrin alone) daily for the first 6 months of life, given independent of feeding methods. One hundred and seventy-eight children completed the study; blood samples were available from 60 children in the placebo group and 58 children in the probiotic group. Infant cytokine (IL-5, IL-6, IL-10, IL-13, TNF-alpha or TGF-beta) responses to tetanus toxoid (TT), house dust mite (HDM), ovalbumin (OVA), beta-lactoglobulin (BLG), Staphylococcus enterotoxin B (SEB) and phytohaemaglutinin (PHA) were measured at 6 months of age. RESULTS: Children who received the probiotics showed reduced production of IL-5 and TGF-beta in response to polyclonal (SEB) stimulation (P=0.044 and 0.015, respectively). They also demonstrated significantly lower IL-10 responses to TT vaccine antigen compared with the placebo group (P=0.03), and this was not due to any differences in vaccination. However, there were no significant effects of probiotics on either Type 1 (Th1) or Type 2 (Th2) T helper cell responses to allergens or other stimuli. The only other effects observed were for reduced TNF-alpha and IL-10 responsiveness to HDM allergens in children receiving probiotics (P=0.046 and 0.014, respectively). CONCLUSIONS: In summary, although we did not see any consistent effects on allergen-specific responses, our study suggests that probiotics may have immunomodulatory effects on vaccine responses. The significance and clinical relevance of this need to be determined in further studies.

Allergens↗

PubMed2004

Application of genotypic and phenotypic analyses to commercial probiotic strain identity and relatedness.

AIMS: The objective of this study was to generate strain-specific genomic patterns of a bank of 67 commercial and reference probiotic strains, with a focus on probiotic lactobacilli. METHODS AND RESULTS: Pulsed-field gel electrophoresis (PFGE) was used as the primary method for strain differentiation. This method was compared with carbohydrate fermentation analysis. To supplement visual comparison, PFGE patterns were analysed quantitatively by cluster analysis using unweighted pair group method with arithmetic averages. SmaI, NotI and XbaI were found to effectively generate clear and easy-to-interpret PFGE patterns of a range of probiotic strains. Some probiotic strains from different sources shared highly similar PFGE patterns. CONCLUSIONS: Results document the value of genotypic strain identification methods, combined with phenotypic methods, for determining probiotic strain identity and relatedness. No correlation was found between relatedness determined by carbohydrate fermentation profiles alone compared with PFGE analysis alone. Some commercial strains are probably derived from similar sources. SIGNIFICANCE AND IMPACT OF THE STUDY: This approach is valuable to the probiotic industry to develop commercial strain identification patterns, to provide quality control of strain manufacturing production runs, to track use of protected strains and to determine the relatedness among different research and commercial probiotic strains.

Bacterial Typing Techniques↗