Pediococcus pentosaceus NB-17 for probiotic use

Probiotic Properties of Pediococcus pentosaceus JBCC 106 and Its Lactic Acid Fermentation on Broccoli Juice

To understand the biological roles of Pediococcus pentosaceus strains as probiotics isolated from the traditional Korean fermented food, Jangajji, Pediococcus pentosaceus was selected based on its high cinnamoyl esterase (CE) and antioxidant activities. The acid and bile stability, intestinal adhesion, antagonistic activity against human pathogens, cholesterol-lowering effects, and immune system stimulation without inflammatory effects were evaluated. Nitric oxide (NO) levels were measured in co-culture with various bacterial stimulants. Fermentation ability was measured by using a broccoli matrix and the sulforaphane levels were measured. Resistance to acidic and bilious conditions and 8% adherence to Caco-2 cells were observed. Cholesterol levels were lowered by 51% by assimilation. Moreover, these strains exhibited immunomodulatory properties with induction of macrophage TNF-α and IL-6 and had microstatic effects on various pathogens. Co-culture with various bacterial stimulants resulted in increased NO production. Fermentation activity was increased with the strains, and higher sulforaphane levels were observed. Therefore, in the future, the applicability of the selected strain to broccoli matrix-based fermented functional foods should be confirmed.

Beneficial features of pediococcus: from starter cultures and inhibitory activities to probiotic benefits

Pediococci are lactic acid bacteria (LAB) which have been used for centuries in the production of traditional fermented foods. There fermentative abilities were explored by the modern food processing industry in use of pediococci as starter cultures, enabling the production of fermented foods with distinct characteristics. Furthermore, some pediococci strains can produce bacteriocins and other antimicrobial metabolites (AMM), such as pediocins, which are increasingly being explored as bio-preservatives in various food matrices. Due to their versatility and inhibitory spectrum, pediococci bacteriocins and AMM are being extensively researched not only in the food industry, but also in veterinary and human medicine. Some of the pediococci were evaluated as potential probiotics with different beneficial areas of application associated with human and other animals' health. The main taxonomic characteristics of pediococci species are presented here, as well as and their potential roles and applications as starter cultures, as bio-preservatives and as probiotic candidates.

Pediococcus pentosaceus: Screening and Application as Probiotics in Food Processing

Lactic acid bacteria (LAB) are vital probiotics in the food processing industry, which are widely spread in food additives and products, such as meat, milk, and vegetables. Pediococcus pentosaceus (P. pentosaceus), as a kind of LAB, has numerous probiotic effects, mainly including antioxidant, cholesterol-lowering, and immune effects. Recently, the applications in the probiotic- fermentation products have attracted progressively more attentions. However, it is necessary to screen P. pentosaceus with abundant functions from diverse sources due to the limitation about the source and species of P. pentosaceus. This review summarized the screening methods of P. pentosaceus and the exploration methods of probiotic functions in combination with the case study. The screening methods included primary screening and rescreening including gastric acidity resistance, bile resistance, adhesion, antibacterial effects, etc. The application and development prospects of P. pentosaceus were described in detail, and the shortcomings in the practical application of P. pentosaceus were evaluated to make better application of P. pentosaceus in the future.

Evaluation of Geum urbanum L. extracts with respect to their antimicrobial potential

Preparations derived from roots and rhizomes of Geum urbanum L. are traditionally used for the treatment of ulcers and irritations of mucous membranes of the mouth, stomach, and intestinal tract. In complementary medicine, fermentation is one of the methods applied to recover plant extracts used for the production of such pharmaceutical preparations. The present study was performed to characterize the secondary metabolites and to evaluate the antimicrobial potential of different G. urbanum root and rhizome extracts. For this purpose, individual metabolites of fresh and fermented G. urbanum root and rhizome extracts were analyzed by HPLC-DAD-MS n and GC-MS. Among others, rare ellagitannin-sulfates could be characterized by LC-MS n . In addition, the antibacterial activity of various extracts of fresh and dried G. urbanum roots and rhizomes against Staphylococcus aureus (ATCC 6538) and Cutibacterium acnes (CP033842.1; FDAARGOS_503 chromosome) were assessed and compared to that of G. rivale. Furthermore, low- and high-molecular tannins were fractionated by column chromatography, demonstrating the latter to exhibit highest antibacterial activity.

Mucosa-adherent Pediococcus Pentosaceus I44 isolated from healthy human and effect of oleic acid on its probiotic properties

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A Gram-positive, catalase-negative cocci identified as Pediococcus pentosaceus I44 was isolated from the ileal tissue of a healthy Indian.

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This isolate exhibited good tolerance to gastrointestinal conditions and bile stress.

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Oleic acid and oleic acid containing compounds (tween-80, olive oil and sesame oil) were found to have a significant effect on the stress tolerance ability and surface properties of this isolate invitro.

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Pediococcus pentosaceus I44 represents the autochthonous gut bacterial community and understanding such isolates provide useful insights into their role in human metabolism and health.

With the aim of selectively isolating and understanding the cultivable lactic acid bacteria that are autochthonous to human gut, biopsy samples were collected from the terminal ileum and caecum of healthy volunteers who underwent routine colonoscopy procedure. The use of tissue samples (over stool samples) provides for a better expression of the autochthonous bacterial population of the human gut. The strains that were stable after many rounds of sub-culture were identified and studied further. One such ileal isolate, a Gram-positive, catalase-negative cocci was identified to be Pediococcus pentosaceus I44. It was studied for its gastric tolerance, bile tolerance and surface properties, and reported here. The effect of tween-80, oleic acid, extra virgin olive oil and sesame oil on the aforementioned properties of P. pentosaceus I44 was also analysed. The isolate was able to survive well in simulated gastric fluid of pH 3.0 followed by treatment in simulated intestinal fluid with a survival percentage of around 70%. It was, however, unable to withstand pH 2.0 even in the presence of supplements. It showed good tolerance to bile stress (1% w/v), and its cell surface was found to be hydrophilic. P. pentosaceus I44 showed good aggregation of 87% after 24 h, with oleic acid having a significant effect on the isolate's aggregation potential. P. pentosaceus I44 is one of the few mucosa-bound cultivable bacteria that are adapted for survival in human colon. Studying and analysing such isolates might provide useful insights into their role in metabolism and health.

Functions of small RNAs in Lactobacillus casei-Pediococcus group of lactic acid bacteria using fragment analysis

Small RNAs (sRNA) are non-cording RNAs composed of 50∼400 nt responsible for coordinating the adaption of Escherichia coli and other bacteria to changing environmental conditions, including pH and temperature. However, the role of sRNAs in lactic acid bacteria (LAB) has not yet been clarified. In this study, we used the Lactobacillus casei-Pediococcus group to evaluate the function of sRNAs in LAB, using RNA sequencing in the exponential growth phase and stationary phase to map and analyze sRNA fragments, which were categorized as Pediococcus pentosaceus and Lactobacillus paracasei. We evaluated the role of sRNAs in nutrient synthesis for cell growth in exponential growth phase and in protein and biofilm biosynthesis for cell body durability. During exponential growth, the sRNA fragments were found to be involved in the stress response in Pediococcus pentosaceus and in environmental adaption in Lactobacillus paracasei. The results suggest that the function of sRNA can be characterized from sRNA fragments using RNA sequencing during the exponential growth and stationary phases in Lactobacillus casei-Pediococcus group.

Evaluation of Probiotic Properties of Pediococcus acidilactici M76 Producing Functional Exopolysaccharides and Its Lactic Acid Fermentation of Black Raspberry Extract

This study aimed to determine the probiotic potential of Pediococcus acidilactici M76 (PA-M76) for lactic acid fermentation of black raspberry extract (BRE). PA-M76 showed outstanding probiotic properties with high tolerance in acidic GIT environments, broad antimicrobial activity, and high adhesion capability in the intestinal tract of Caenorhabditis elegans. PA-M76 treatment resulted in significant increases of pro-inflammatory cytokine mRNA expression in macrophages, indicating that PA-M76 elicits an effective immune response. When PA-M76 was used for lactic acid fermentation of BRE, an EPS yield of 1.62 g/L was obtained under optimal conditions. Lactic acid fermentation of BRE by PA-M76 did not significantly affect the total anthocyanin and flavonoid content, except for a significant increase in total polyphenol content compared to non-fermented BRE (NfBRE). However, fBRE exhibited increased DPPH radical scavenging activity, linoleic acid peroxidation inhibition rate, and ABTS scavenging activity of fBRE compared to NfBRE. Among the 28 compounds identified in the GC-MS analysis, esters were present as the major groups. The total concentration of volatile compounds was higher in fBRE than that in NfBRE. However, the undesirable flavor of terpenes decreased. PA-M76 might be useful for preparing functionally enhanced fermented beverages with a higher antioxidant activity of EPS and enhanced flavors.

Induced changes in bioactive compounds of broccoli juices after fermented by animal- and plant-derived Pediococcus pentosaceus

To investigate the metabolism of bioactive compounds in broccoli juice fermented by animal- and plant-derived Pediococcus pentosaceus, levels of glucosinolates (GS), sulforaphane, and sulforaphane-nitrile; activity of myrosinase; and profiles of organic acids, vitamins, and amino acids were determined. Three aliphatic GS and four indolyl GS were identified. After fermentation by plant- and animal-derived P. pentosaceus, myrosinase activity, contents of total GS and sulforaphane nitrile, and levels of malic acid, acetic acid, ascorbic acid, and thiamine significantly decreased in pasteurized broccoli juice, whereas levels of sulforaphane, lactic acid, and citric acid significantly increased. Fermentation by plant-derived P. pentosaceus decreased levels of riboflavin and β-carotene and increased total levels of free amino acids, in contrast to the trends observed in broccoli juice after fermentation by animal-derived P. pentosaceus. This study indicates that P. pentosaceus may potentially be used in starter cultures to improve the nutritional and functional properties of fermented foods.

Pediococcus pentosaceus, a future additive or probiotic candidate

Background

Pediococcus pentosaceus, a promising strain of lactic acid bacteria (LAB), is gradually attracting attention, leading to a rapid increase in experimental research. Due to increased demand for practical applications of microbes, the functional and harmless P. pentosaceus might be a worthwhile LAB strain for both the food industry and biological applications.

Results

As an additive, P. pentosaceus improves the taste and nutrition of food, as well as the storage of animal products. Moreover, the antimicrobial abilities of Pediococcus strains are being highlighted. Evidence suggests that bacteriocins or bacteriocin-like substances (BLISs) produced by P. pentosaceus play effective antibacterial roles in the microbial ecosystem. In addition, various strains of P. pentosaceus have been highlighted for probiotic use due to their anti-inflammation, anticancer, antioxidant, detoxification, and lipid-lowering abilities.

Conclusions

Therefore, it is necessary to continue studying P. pentosaceus for further use. Thorough study of several P. pentosaceus strains should clarify the benefits and drawbacks in the future.

Infantile Colic Treated With Bifidobacterium longum CECT7894 and Pediococcus pentosaceus CECT8330: A Randomized, Double-Blind, Placebo-Controlled Trial

Background: Colic is a common condition in infants <4 months of age. Attempts to treat infantile colic with probiotics have shown variable efficacy and overall low evidence of success. In this work, we tested the hypothesis that oral administration of Bifidobacterium longum CECT7894 (KABP042) and Pediococcus pentosaceus CECT8330 (KABP041) mix (1 × 10⁹ colony forming units) would improve the symptoms of infantile colic. Methods: A total of 112 exclusively breastfed or mixed fed infants aged <2 months and meeting the ROME IV criteria for infantile colic were recruited. The infants were randomized in a double-blind, placebo-controlled trial to receive orally administered probiotics (intervention group, IG, n = 48) or placebo (placebo group, PG, n = 42) daily for 21 days. Results: Infants in the IG had significantly shorter crying time (p < 0.001) on day 7 [IG vs. PG, median (25-75th percentile): 38 (3.5-40.5) vs. 62 (40-108) min/day], day 14 [IG vs. PG: 20 (0-40) vs. 50 (30-75) min/day], and day 21 [IG vs. PG: 14 (0-33) vs. 40 (28-62) min/day]. Higher responder ratio and fewer crying/fussing episodes on days 7, 14, and 21 and better stool consistency on day 21 were observed in the IG (p < 0.01) as compared to the PG. Conversely, no significant effects on stool frequency or quality of life were observed. Conclusions: In summary, daily oral administration of B. longum CECT7894 (KABP042) and P. pentosaceus CECT8330 (KABP041) was an effective treatment for shortening crying time due to infantile colic and for improving fecal consistency. This trial was registered retrospectively in December 2019 with a trial number of ISRCTN92431452.

Molecular insights into probiotic mechanisms of action employed against intestinal pathogenic bacteria

Gastrointestinal (GI) diseases, and in particular those caused by bacterial infections, are a major cause of morbidity and mortality worldwide. Treatment is becoming increasingly difficult due to the increase in number of species that have developed resistance to antibiotics. Probiotic lactic acid bacteria (LAB) have considerable potential as alternatives to antibiotics, both in prophylactic and therapeutic applications. Several studies have documented a reduction, or prevention, of GI diseases by probiotic bacteria. Since the activities of probiotic bacteria are closely linked with conditions in the host's GI-tract (GIT) and changes in the population of enteric microorganisms, a deeper understanding of gut-microbial interactions is required in the selection of the most suitable probiotic. This necessitates a deeper understanding of the molecular capabilities of probiotic bacteria. In this review, we explore how probiotic microorganisms interact with enteric pathogens in the GIT. The significance of probiotic colonization and persistence in the GIT is also addressed.

In vitro probiotic properties of Pediococcus pentosaceus L1 and its effects on enterotoxigenic Escherichia coli-induced inflammatory responses in porcine intestinal epithelial cells

This study aimed to evaluate in vitro probiotic characteristics of Pediococcus pentosaceus strain L1 from pickled radish and investigate its impacts on inflammatory responses in porcine intestinal epithelial cells (IEC) to enterotoxigenic Escherichia coli (ETEC) F4⁺. The abilities of P. pentosaceus L1 to tolerate gastrointestinal conditions and to antagonize ETEC F4⁺ growth were determined. Adhesion of P. pentosaceus L1 and its effect on ETEC F4⁺ adhesion to porcine IPEC-J2 IEC were evaluated. Furthermore, the effects of this strain on proinflammatory gene expression and cytokines/chemokine production in porcine IPEC-J2 IEC induced by ETEC F4⁺ were determined. P. pentosaceus L1 showed good tolerance to the medium adjusted at pH 2.5 and consequently supplemented with 0.3% oxgall. Reduction of ETEC F4⁺ growth in co-culture with L1 was found. Effective adhesion of L1 to porcine. IPEC-J2 IEC was observed under these conditions. P. pentosaceus L1 decreased the adhesion of ETEC F4⁺ to IPEC-J2 IEC and the extent of inhibition of ETEC F4⁺ adhesion depended on the timing of L1 addition. Further analysis revealed down-regulation of expression of ETEC F4⁺-induced proinflammatory genes encoding interleukin-6 (IL-6), tumor necrosis factor-α (TNF-α), and interleukin-8 (IL-8) in IPEC-J2 IEC. Expression of the genes involved in NF-κB pathway, including RELA and NFKB1, were also repressed, as was production of IL-6, TNF-α, and IL-8. These results indicate that P. pentosaceus L1 may have potential as a probiotic for control of ETEC infection in pigs.

Culture Dependent and Independent Analysis of Potential Probiotic Bacterial Genera and Species Present in the Phyllosphere of Raw Eaten Produce

The plant phyllosphere is colonized by a complex ecosystem of microorganisms. Leaves of raw eaten vegetables and herbs are habitats for bacteria important not only to the host plant, but also to human health when ingested via meals. The aim of the current study was to determine the presence of putative probiotic bacteria in the phyllosphere of raw eaten produce. Quantification of bifidobacteria showed that leaves of Lepidium sativum L., Cichorium endivia L., and Thymus vulgaris L. harbor between 10³ and 10⁶ DNA copies per gram fresh weight. Total cultivable bacteria in the phyllosphere of those three plant species ranged from 10⁵ to 10⁸ CFU per gram fresh weight. Specific enrichment of probiotic lactic acid bacteria from C. endivia, T. vulgaris,Trigonella foenum-graecum L., Coriandrum sativum L., and Petroselinum crispum L. led to the isolation of 155 bacterial strains, which were identified as Pediococcus pentosaceus, Enterococcus faecium, and Bacillus species, based on their intact protein pattern. A comprehensive community analysis of the L. sativum leaves by PhyloChip hybridization revealed the presence of genera Bifidobacterium, Lactobacillus, and Streptococcus. Our results demonstrate that the phyllosphere of raw eaten produce has to be considered as a substantial source of probiotic bacteria and point to the development of vegetables and herbs with added probiotic value.

Complete Genome Sequence of Pediococcus pentosaceus Strain wikim 20, Isolated from Korean Kimchi

Pediococcus pentosaceus strain wikim 20 is a lactic acid bacterium that was isolated from kimchi, a representative traditional Korean fermented food. Here, we announce the complete genome sequence of P. pentosaceus strain wikim 20 consisting of a 1,830,629-bp chromosome and provide a description of its annotation.

Preliminary probiotic and technological characterization of Pediococcus pentosaceus strain KID7 and in vivo assessment of its cholesterol-lowering activity

The study was aimed to characterize the probiotic properties of a Pediococcus pentosaceus strain, KID7, by in vitro and in vivo studies. The strain possessed tolerance to oro-gastrointestinal transit, adherence to the Caco-2 cell line, and antimicrobial activity. KID7 exhibited bile salt hydrolase activity and cholesterol-lowering activity, in vitro. In vivo cholesterol-lowering activity of KID7 was studied using atherogenic diet-fed hypercholesterolemic mice. The experimental animals (C57BL/6J mice) were divided into 4 groups viz., normal diet-fed group (NCD), atherogenic diet-fed group (HCD), atherogenic diet- and KID7-fed group (HCD-KID7), and atherogenic diet- and Lactobacillus acidophilus ATCC 43121-fed group (HCD-L.ac) as positive control. Serum total cholesterol (T-CHO) level was significantly decreased by 19.8% in the HCD-KID7 group (P < 0.05), but not in the HCD-L.ac group compared with the HCD group. LDL cholesterol levels in both HCD-KID7 and HCD-L.ac groups were decreased by 35.5 and 38.7%, respectively, compared with HCD group (both, P < 0.05). Glutamyl pyruvic transaminase (GPT) level was significantly lower in the HCD-KID7 and HCD-L.ac groups compared to HCD group and was equivalent to that of the NCD group. Liver T-CHO levels in the HCD-KID7 group were reduced significantly compared with the HCD group (P < 0.05) but not in the HCD-L.ac group. Analysis of expression of genes associated with lipid metabolism in liver showed that low-density lipoprotein receptor (LDLR), cholesterol-7α-hydroxylase (CYP7A1) and apolipoprotein E (APOE) mRNA expression was significantly increase in the HCD-KID7 group compared to the HCD group. Furthermore, KID7 exhibited desired viability under freeze-drying and subsequent storage conditions with a combination of skim milk and galactomannan. P. pentosaceus KID7 could be a potential probiotic strain, which can be used to develop cholesterol-lowering functional food after appropriate human clinical trials.

Probiotic-based strategies for therapeutic and prophylactic use against multiple gastrointestinal diseases

Probiotic bacteria offer a number of potential health benefits when administered in sufficient amounts that in part include reducing the number of harmful organisms in the intestine, producing antimicrobial substances and stimulating the body's immune response. However, precisely elucidating the probiotic effect of a specific bacterium has been challenging due to the complexity of the gut's microbial ecosystem and a lack of definitive means for its characterization. This review provides an overview of widely used and recently described probiotics, their impact on the human's gut microflora as a preventative treatment of disease, human/animal models being used to help show efficacy, and discusses the potential use of probiotics in gastrointestinal diseases associated with antibiotic administration.

Evaluation of characteristics of Pediococcus spp. to be used as a vaginal probiotic

AIMS

The aim of our research was to select, identify and characterize an isolate of lactic acid bacteria to be considered as a vaginal probiotic.

METHODS AND RESULTS

Thirty-five isolates of Pediococcus spp. showed bacteriocinogenic activity against Listeria monocytogenes and the ability to survive in simulated vaginal fluid (SVF) at pH 4.2. One isolate of Pediococcus spp. was selected and characterized to evaluate its safety before the use as vaginal probiotic. Pediococcus pentosaceus SB83 did not show the presence of virulence factors such as the production of gelatinase, lipase and DNase, haemolytic activity, nor the presence of virulence genes (genes esp, agg, gelE, efaAfm, efaAfs, cylA, cylB and cylM). Pediococcus pentosaceus SB83 was considered sensitive to chloramphenicol, gentamicin, streptomycin, kanamycin, erythromycin and ampicillin. This strain was considered resistant to tetracycline and vancomycin. Pediococcus pentosaceus SB83 was a biofilm producer at different pH values (4.2, 5.5 and 6.5) in SVF and in de Man, Rogosa and Sharpe medium.

CONCLUSIONS

The in vitro results provide a basis for the use of P. pentosaceus SB83 as a vaginal probiotic, to prevent colonization by L. monocytogenes in pregnant women.

SIGNIFICANCE AND IMPACT OF STUDY

The application of vaginal probiotics could have the potential for preventing vaginal infections and consequently reduce abortion and neonatal infections.

Influence of NaCl and NaNO3 on sinigrin hydrolysis by foodborne bacteria

The glucosinolate sinigrin (SNG) is converted by endogenous plant myrosinase or by bacterial myrosinase-like activity to form the potent antimicrobial allyl isothiocyanate. In order to use SNG as a natural antimicrobial precursor in food, it became important to better understand the ability of bacteria to synthesize the enzyme(s) and understand factors influencing this synthesis at a constant SNG concentration. Eight spoilage, pathogenic, or starter culture bacteria were grown separately in medium containing individual or combined salts with SNG. SNG degradation by the bacteria and the formation of its major degradation product, allyl isothiocyanate, were followed for 12 days at 30 or 35°C. The bacterial strains varied in their ability to metabolize SNG, and this was enhanced by NaCl and/or NaNO(3). SNG hydrolysis took place after 4 days, and the greatest amount occurred by day 12. At 12 days, Escherichia coli O157:H7 showed the greatest capacity to hydrolyze SNG (45.3% degradation), followed by Staphylococcus carnosus (44.57%), while Pseudomonas fluorescens was not active against SNG. The ability of tested strains to metabolize SNG, in decreasing order, was as follows: Escherichia coli O157:H7 > Staphylococcus carnosus > Staphylococcus aureus > Pediococcus pentosaceus > Salmonella Typhimurium > Listeria monocytogenes > Enterococcus faecalis > Pseudomonas fluorescens.

Probiotic properties of non-conventional lactic acid bacteria: immunomodulation by Oenococcus oeni

The widely used probiotic bacteria belong to the genera Lactobacillus and Bifidobacterium and have in most cases been isolated from the human gastrointestinal tract. However, other "less conventional" bacteria, from allochthonous or extremophilic origin, sharing similar structural or functional features, may also confer specific health benefits to a host. Firstly, we explored the in vitro immuno-modulatory or immune-stimulatory activities of 25 wine lactic acid bacteria belonging to Oenococcus oeni and Pediococcus parvulus. While cytokines released by peripheral blood mononuclear cells (PBMCs) stimulated by P. parvulus strains, showed little variation, O. oeni strains induced strain-specific cytokine patterns. Some O. oeni strains were then further analyzed under various conditions for growth, dose and culture medium. In a second phase, we evaluated the oral tolerance and safety of two strains of O. oeni in mice fed a high dose of bacteria for a week. Finally, evidence was gathered on the in vivo anti-inflammatory potential of a selected O. oeni strain using an experimental 2,4,6-trinitrobenzene sulfonic acid (TNBS)-induced colitis mouse model. Although results did not match the anti-inflammatory levels obtained with certain conventional probiotics, strain IOEB 9115 significantly lowered colonic injury and alleviated colitis symptoms. The 'natural' tolerance towards acid, ethanol, and phenolic compounds of O. oeni strains combined with a measureable immunomodulatory potential, suggest a possible use of selected strains isolated from wine as live probiotics.

Study of the physicochemical and biological stability of pediocin PA-1 in the upper gastrointestinal tract conditions using a dynamic in vitro model

AIMS

To evaluate the survival of Pediococcus acidilactici UL5 and its ability to produce pediocin PA-1 during transit in an artificial gastrointestinal tract (GIT). To investigate the physicochemical and biological stability of purified pediocin PA-1 under GIT conditions.

METHODS AND RESULTS

Skim milk culture of Ped. acidilactici UL5 was fed to a dynamic gastrointestinal (GI) model known as TIM-1, comprising four compartments connected by computer-controlled peristaltic valves and simulating the human stomach, duodenum, jejunum and ileum. This strain tolerated a pH of 2·7 in the gastric compartment, while lower pH reduced its viability. Bile salts in the duodenal compartment brought a further 4-log reduction after 180 min of digestion, while high viable counts (up to 5 × 10(7) CFU ml(-1) fermented milk) of Ped. acidilactici were found in both the jejunal and ileal compartments. Pediococcus acidilactici recovered from all four compartments was able to produce pediocin at the same level as unstressed cells. The activity of the purified pediocin in the gastric compartment was slightly reduced after 90 min of gastric digestion, while no detectable activity was found in the duodenal, jejunal and ileal compartments during 5 h of digestion. HPLC analysis showed partial degradation of the pediocin peptide in the duodenal compartment and massive breakdown in the jejunal and ileal compartments.

CONCLUSIONS

Pediococcus acidilactici UL5 showed high resistance to GIT conditions, and its ability to produce pediocin was not affected, suggesting its potential as a probiotic candidate. The physicochemical and biological stability of pediocin was significantly poor under GIT conditions.

SIGNIFICANCE AND IMPACT OF THE STUDY

Pediococcus acidilactici UL5 appears to be a potential probiotic candidate because its capacity to produce pediocin PA-1 is not affected by the GI conditions as well as the strain shows an acceptable survival rate. Meanwhile, purified pediocin PA-1 losses activity during GIT transit; microcapsules could be used to deliver it to the target site.