Bile Salt Concentration Research Articles

Evaluation of probiotic characteristics and whole genome analysis of Bacillus velezensis R-71003 isolated from the intestine of common carp (Cyprinus carpio L.) for its use as a probiotic in aquaculture

Probiotics have been widely used in aquaculture and may serve as a potential alternative to antibiotics. Diverse sources of probiotics have different effects on the host, and the application of native probiotics isolated from target fish may play a better role. This study was conducted to evaluate the probiotic potential of the bacteria isolated from the gut of common carp (Cyprinus carpio L.). Based on morphological, 16 S rRNA sequencing and whole-genome sequencing analysis, an isolated strain that simultaneously produces protease, mannanase, amylase, and cellulose was identified as Bacillus velezensis R-71003. This strain showed antagonistic activity against various pathogens. Further studies showed that B. velezensis R-71003 was susceptible to ampicillin, gentamicin, penicillin G, erythromycin, chloramphenicol, amikacin, cefamezin, sulfamethoxazole, ciprofloxacin and norfloxacin. Additionally, B. velezensis R-71003 met the safety criteria based on safety evaluation results, such as haemolytic activity and biosafety tests in common carp. Moreover, B. velezensis R7–1003 was resistant to low pH (2) and higher bile salt concentration (0.3 %) and showed higher viability ability after high temperature exposure (60, 70, and 80 °C), as well as higher auto-aggregation and cell-surface hydrophobicity. In addition, the challenge test showed that B. velezensis R-71003 significantly increased the survival rate of common carp after challenged with Aeromonas hydrophila. Finally, the growth-promoting effects of sodium gluconate on B. velezensis R-71003 were evaluated. The results indicated that a low concentration of sodium gluconate could promote the growth of B. velezensis R-71003 and increase the expression levels of dnaA and yabD. Whole-genome analysis revealed that genome contains genes related to the biosynthesis of antibacterial substances, digestive enzymes, amino acids and vitamins, as well as stress resistance. The results collectively suggest that B. velezensis R-71003 exhibited good probiotic potential, and its combined application with sodium gluconate may be used to improve the health status of aquatic animals.

Hepatic Expression of the Na+-Taurocholate Cotransporting Polypeptide Is Independent from Genetic Variation.

The hepatic Na+-taurocholate cotransporting polypeptide NTCP/SLC10A1 is important for the uptake of bile salts and selected drugs. Its inhibition results in increased systemic bile salt concentrations. NTCP is also the entry receptor for the hepatitis B/D virus. We investigated interindividual hepatic SLC10A1/NTCP expression using various omics technologies. SLC10A1/NTCP mRNA expression/protein abundance was quantified in well-characterized 143 human livers by real-time PCR and LC-MS/MS-based targeted proteomics. Genome-wide SNP arrays and SLC10A1 next-generation sequencing were used for genomic analyses. SLC10A1 DNA methylation was assessed through MALDI-TOF MS. Transcriptomics and untargeted metabolomics (UHPLC-Q-TOF-MS) were correlated to identify NTCP-related metabolic pathways. SLC10A1 mRNA and NTCP protein levels varied 44-fold and 10.4-fold, respectively. Non-genetic factors (e.g., smoking, alcohol consumption) influenced significantly NTCP expression. Genetic variants in SLC10A1 or other genes do not explain expression variability which was validated in livers (n = 50) from The Cancer Genome Atlas. The identified two missense SLC10A1 variants did not impair transport function in transfectants. Specific CpG sites in SLC10A1 as well as single metabolic alterations and pathways (e.g., peroxisomal and bile acid synthesis) were significantly associated with expression. Inter-individual variability of NTCP expression is multifactorial with the contribution of clinical factors, DNA methylation, transcriptional regulation as well as hepatic metabolism, but not genetic variation.

Probiotic Potentials of Lactic Acid Bacteria Isolated from Fermented Foods

This study investigated the probiotic potentials of seven lactic acid bacteria (LAB) strains at different temperatures, pH, and bile salt concentrations. Their antimicrobial activity and antibiotic susceptibility were also determined. There were significant (P˂0.05) differences in the LAB growth at 45-650C with viable counts ranging from 4.28-8.34 Log10 Cfu/ml after 48 h. The LAB strains showed significant (P˂0.05) increase at pH 2, 2.5 and 3 after 3 and 6 h. L. parabuchneri LMG was viable at 45 and 65oC with 99.30 and 65.00% survival respectively. The LAB showed high resistance to 0.3% bile salt at 97.90%. L. plantarum CIP was viable with 95.40% survival at pH 3.0 after 3 h. All the LAB strains were susceptible to cefuroxime (20 µg/ml) and erythromycin (10 µg/ml) at 13.00-45.00 mm zone of inhibition (ZOI). They had strong antimicrobial activity against Escherichia coli ATCC 25922, Pseudomonas aeruginosa ATCC 9027 and Listeria monocytogenes ATCC 15313. Leuconostoc mesenteroides LM and L. brevis ATCC inhibited the five tested food borne pathogens with ZOI varying from 8.00-26.00 mm. The results from this study showed that the LAB strains isolated from fermented foods had probiotic potential and can be used for research and commercial purposes.

Psychobiotic Potential of Gamma-Aminobutyric Acid–Producing Marine Enterococcus faecium SH9 from Marine Shrimp

Psychobiotics are a novel class of probiotics with potential to confer mental wellness via production of neuroactive compounds such as gamma-aminobutyric acid (GABA). The demand for new biological sources of GABA has increased steadily. Therefore, the current study reports the isolation of 17 presumptive lactic acid bacteria (LAB) from marine samples and their screening for GABA synthesis from monosodium glutamate (MSG) using thin-layer chromatography (TLC). The isolate SH9 was selected as a high GABA producing strain. The GABA content of SH9 cell free supernatant (CFS) was quantitatively determined by high performance liquid chromatography (HPLC) to be 0.97 g/L. SH9 was identified biochemically and molecularly as Enterococcus faecium (identity 99%). Moreover, SH9 demonstrated promising probiotic potentials; it gave no signs of hemolysis and could survive at low pH values and high bile salt concentrations. It also exhibited antimicrobial activity against highly pathogenic strains and the ability to grow at 6.5% NaCl. In addition, SH9 CFS showed anti-inflammatory and antioxidant properties. The glutamate decarboxylase (GAD) gene was detected in SH9 by using specific primers. Product of 540 bp was obtained, sequenced, and analyzed (accession number: MW713382). The inferred amino acid sequence was 99.3% identical to Lactobacillus plantarum M-6 gadB gene. The findings of this study suggest that the marine isolate E. faecium SH9 could be used as a novel psychobiotics in the development of GABA rich healthy products.

Production and Characterization of Exopolysaccharide From Newly Isolated Marine Probiotic Lactiplantibacillus plantarum EI6 With in vitro Wound Healing Activity.

Because of its safety, biological activities, and unique properties, exopolysaccharide (EPS) from lactic acid bacteria (LAB) has been developed as a potential biopolymer. A few studies have investigated the EPS produced by marine LAB. This study reports the wound healing activity of an EPS produced by a marine isolate identified as Lactiplantibacillus plantarum EI6, in addition to assessing L. plantarum EI6's probiotic properties. EI6 demonstrated promising antimicrobial activity against different pathogenic bacteria, as well as the ability to withstand stomach pH 3, tolerate 0.3% bile salt concentration, and exhibit no signs of hemolysis. Furthermore, EI6 was able to produce 270 mg/L of EPS upon growth for 48 h at 37°C in an MRS medium enriched with 1.0% of sucrose. The chemical features of the novel EI6-EPS were investigated: the UV-vis estimated a high carbohydrate content of ~91.5%, and the FTIR emphasized its polysaccharide nature by the characteristic hydroxyl, amide I, II, & III, and glycosidic linkage regions. The GC-MS and NMR analyses revealed the existence of five monosaccharides, namely, rhamnose, galactose, mannose, glucose, and arabinose, existing mainly in the pyranose form and linked together by α- and β-glycosidic linkages. EI6-EPS was found to be safe (IC50 > 100 μg/ml) and induced human skin fibroblasts (HSF) proliferation and migration. These findings imply that EI6 can be used as a safe source of bioactive polymer in wound care.

Photophysical Behaviour of Novel Quaternary Pyrenoyl Salts and Their Sensitivity Towards Bile Salt Micellization.

The present work describes the synthesis and characterization of pyrene derivatives, N-(1-Pyrenoylmethyl) pyridinium bromide (PM-PB) and N-(1-Pyrenoylmethyl)-N,N,N-triethylammonium bromide (PM-TAB). The photophysical behavior of these molecules has been studied in various protic and aprotic solvents. Using steady state fluorescence intensity, fluorescence anisotropy and dynamic fluorescence lifetime studies, the sensitivity of these molecules towards the micellization process of bile salts has been monitored. These derivatives have been effectively used in estimating critical micellar concentration (CMC) of bile salt, sodium deoxycholate (NaDC).

Orlistat disposition in the human jejunum and the effect of lipolysis inhibition on bile salt concentrations and composition

The lipolysis-mediated postprandial small intestinal environment is known to influence the solubilisation and subsequent absorption of lipophilic drugs. In a previously performed small-scale clinical study in healthy volunteers, co-administration of the lipase inhibitor orlistat increased jejunal solubilisation and systemic absorption of fenofibrate after intake of the lipid-based formulation Fenogal. In the present study, the jejunal disposition of the locally acting orlistat was assessed and linked to fenofibrate solubilisation. In addition, the effect of orlistat-induced lipolysis inhibition on bile salt concentrations and composition was evaluated. Orlistat was distributed predominantly in the lipid layer, as indicated by a 5- to 14-fold higher AUC0-320 min in the total jejunal samples as compared to the micellar layers. No effect of orally administered orlistat on bile salt composition or total concentrations (ranging from 1.5 to 24.8 mM and 1.8 to 33.2 mM with and without orlistat co-administration, respectively) could be observed. The intraluminal presence of orlistat in the total jejunal samples correlated with the increased fenofibrate solubilisation in the jejunum (r = 0.9344) and enhanced absorption (r = 0.8184), highlighting the importance of the intraluminal lipid phase in lipophilic drug absorption.

Characterizing the Capacity of Acinetobacter calcoaceticusto Grow in Intestinal Conditions and Modulate the Gut Epithelium

BackgroundAcinetobacter species can occupy several ecological niches, including the mammalian intestine. Acinetobacter has been identified in the human fecal microbiota and it is speculated that the gut can serve as a reservoir for this pathobiont. The Acinetobacter calcoaceticus–Acinetobacter baumannii complex is a common cause of drug‐resistant pneumonia, urinary tract, skin and soft tissue infections. A. calcoaceticus has been considered to have relatively low virulence compared to its counterpart A. baumannii since colonization is more frequently noted more than infection clinically. However, few studies have dissected the interaction between A. calcoaceticus and the host, particularly in the gut. In this study, we sought to examine the ability of A. calcoaceticus strains to survive environmental stressors found in the gut. We also examined the reciprocal interactions of A. calcoaceticus strains on the host using colonic organoids.Methods & ResultsThree commercially available strains of A. calcoaceticus and four clinical isolates were grown aerobically in brain heart infusion (BHI) media, subcultured in a fully defined bacterial media termed ZMB1 and exposed to various concentrations of NaCl, ethanol, bile salts and pHs that were designed to mimic the gut. All A. calcoaceticusstrains grew robustly at NaCl concentrations that mirrored the small intestine, but differences were observed between strains at higher NaCl concentrations. Additionally, all strains grew well at pH 7 and pH 6, and exhibited growth reduction at pHs 5 and 4. All strains tolerated several concentrations of bile salts and ethanol; suggesting tolerance for intestinal stressors. Incubation of live A. calcoaceticus strains with inside‐out jejunum and colonic organoids significantly increased pro‐inflammatory cytokines (IL‐1α, KC/IL‐8, MCP‐1 and TNF) and decreased MUC2 and MUC13 transcripts, without altering tight junctions.ConclusionsCollectively, these data demonstrate that A. calcoaceticus is well adapted to the gastrointestinal tract and points to the potential for Acinetobacter to influence the gut epithelium. Of note, we observed differences between lab adapted strains and clinical isolates, highlighting strain variation and indicating that clinical isolate strains should be incorporated into future work.

Physiological properties, survivability and genomic characteristics of Pediococcus pentosaceus for application as a starter culture

There is an increasing demand for the use of Pediococcus pentosaceus in the dairy industry due to its remarkable abilities as a probiotic or starter culture bacterium. This study determines the physiological, survivability and genomic properties of P. pentosaceus to evaluate its potential as a starter culture. The strain showed great tolerance in low pH and high concentrations of bile salts. A good coaggregation ability against pathogens ranging between 71% and 84%, as well as strong biofilm formation ability and remarkable resistance to antibiotics. Whole‐genome sequence results reveal the presence of various genes responsible for stress tolerance, adhesion, biofilm formation, acids, and bile salts tolerance. The findings of this study can be used as essential criteria for selecting P. pentosaceus as a starter culture.

A Brain-Targeted Approach to Ameliorate Memory Disorders in a Sporadic Alzheimer's Disease Mouse Model via Intranasal Luteolin-Loaded Nanobilosomes.

Impaired memory and cognitive function are the main features of Alzheimer’s disease (AD). Unfortunately, currently available treatments cannot cure or delay AD progression. Moreover, the blood–brain barrier hampers effective delivery of treatment to the brain. Therefore, we aimed to evaluate the impact of intranasally delivered luteolin on AD using bile-salt-based nano-vesicles (bilosomes). Different bilosomes were prepared using 23-factorial design. The variables were defined by the concentration of surfactant, the molar ratio of cholesterol:phospholipid, and the concentration of bile salt. Results demonstrated optimized luteolin-loaded bilosomes with particle size (153.2 ± 0.98 nm), zeta potential (−42.8 ± 0.24 mV), entrapment efficiency% (70.4 ± 0.77%), and % drug released after 8 h (80.0 ± 1.10%). In vivo experiments were conducted on an AD mouse model via intracerebroventricular injection of 3 mg/kg streptozotocin. We conducted behavioral, biochemical marker, histological, and immune histochemistry assays after administering a luteolin suspension or luteolin bilosomes (50 mg/kg) intranasally for 21 consecutive days. Luteolin bilosomes improved short-term and long-term spatial memory. They also exhibited antioxidant properties and reduced levels of proinflammatory mediators. They also suppressed both amyloid β aggregation and hyperphosphorylated Tau protein levels in the hippocampus. In conclusion, luteolin bilosomes are an effective, safe, and non-invasive approach with superior cognitive function capabilities compared to luteolin suspension.

In vitro use metabolism of Pediococcus pentosaceus Strain N6 as alternative to natural antibiotics in broiler

The continuous use of antibiotics and inappropriate doses in broilers results in antibiotic residues, thus leading to health problems. An example of LAB that can be used as an antibiotic alternative is the Pediococcus pentosaceus isolate Strain N6. Therefore, this study aims to determine the effectiveness of metabolic antimicrobials produced by the isolates of Pediococcus pentosaceus Strain N6. The method used was an in vitro test consisting of several phases including the test of supernatant antimicrobial activity with pathogenic bacteria (Salmonella typhimurium and E. coli); the test for acidic conditions, bile salts, tolerance to gastric juice, sensitivity to antibiotics, and proteolytic enzymes. The results showed that the antimicrobial activity of the supernatant against Salmonella typhimurium and E. coli bacteria was 15 mm and 18 mm, respectively. This activity is found to be tolerant to acidic conditions, such as pH 2, at 0.5% bile salt concentration, as well as gastric juice, and also sensitive to penicillin, streptomycin, and proteolytic enzymes. Furthermore, the metabolism of an isolate is a useful alternative for antibiotics in chickens.

The probiotic potential of Lactobacillus plantarum strain RW1 isolated from canine faeces.

To evaluation the probiotic potential of Lactobacillus plantarum strain RW1 isolated from healthy dogs for its further utilization as a dietary supplement for dogs. This study aimed to evaluate the probiotic potential of L. plantarum strain RW1 isolated from canine faeces. After confirming by conventional and then by 16S rRNA sequencing, the identified strain RW1 was in vitro screened for its survivability in simulated gastrointestinal conditions, low pH, bile salts and adhesion to gut epithelial tissues, growth inhibitory effects on common pathogens and anti-inflammatory potential by measuring the mRNA expression level of IL-6, IL-8, IL-1β in Salmonella-infected MODE-K cells. Furthermore, the effects on epithelial barrier function and host defensin peptide (beta-defensin 3) was studied by measuring the mRNA expression level of tight junction protein (occludin) and beta-defensin 3 in MODE-K cells. The strain RW1 showed a considerable potential to survive in simulated gastrointestinal environmental conditions, low pH and high bile salt concentrations along with good adhesion to MODE-K cell line. Pathogenic bacterial growth and their adhesion to MODE-K cell line were significantly inhibited by the strain RW1. Real-time PCR analyses demonstrated that the strain RW1 inhibited Salmonella-induced pro-inflammatory cytokines (IL-6, IL-8 and IL-1β) production and reinforced the expression of tight junction protein (occludin). The strain RW1 did not induce mRNA expression of beta-defensin 3. Based on in vitro results, the strain RW1 has the potential to be used as a probiotic supplement in dogs. However, further study involving in vivo health effects is needed. Antibiotics have many side effects and nowadays the probiotics are considered as a potential alternative to antibiotics. This study evaluates the probiotic potential of dog isolated L. plantarum strain RW1 to use it as a dietary supplement in dogs feeding to control infectious diseases.

Cytoprotective Effects of Lactobacilli on Mouse Epithelial Cells during Salmonella Infection

Treatment of common pathogens, such as Salmonella species, Escherichia coli, Staphylococcus aureus, etc., is a big challenge for a practitioner. Antibiotics’ side effects during their application for the treatment of infectious diseases should not be underestimated as they have many issues, such as the transfer of antibiotics-resistant genes, dysbiosis, and antibiotic-resistant strains, which is the main hurdle in the eradication of diseases. To avoid these antibiotics complications, in modern countries, the interest of using probiotics in feed supplementation to promote health and prevent or treat intestinal infectious diseases has been increasing. The purpose of the present study was to evaluate the probiotic potential of three Lactobacilli strains isolated from clinically healthy dogs for their further utilization as a dietary supplement for dogs to avoid pathogenic and antibiotic complication. After 16SrRNA sequencing, in vitro tests were conducted to assess the survival potential of Lactobacilli under simulated gastrointestinal conditions and adhesion ability to the MODE-K cell line, effects on epithelial barrier function, anti-inflammatory activities, effects on host defensin peptides (beta-defensin 3), and inhibitory effects on common pathogens. Lactobacilli showed considerable potential to survive in simulated gastrointestinal environmental conditions, low pH, and high bile salt concentrations along with good adhesion properties with MODE-K cells. Pathogenic bacterial growth and their adhesion to MODE-K cells were significantly inhibited by Lactobacilli. Real-time PCR analyses further demonstrated that the L. acidophilus strain AR1 and AR3 inhibit Salmonella-induced proinflammatory cytokine (IL-6, IL-8, IL-1β) production and reinforce the expression of tight junction protein (occludin). None of the strains induce mRNA expression of beta-defensin 3 in MODE-K cells. Based on the in vitro results, the L. acidophilus strain AR1 has the potential to be supplemented in canine feed. However, further in vivo studies investigating health-promoting effects are awaited.

Probiotic potential and antimicrobial activity of bacteria isolated from fermented foods

Probiotics play a significant role in improving human health and are beneficial for the gastrointestinal tract. In this study, lactic acid bacteria were isolated from different dairy products collected from different locations of Rohtak and Hisar (Haryana). All these isolates were tested and selected based on their ability to resist low and high pH, ability to survive in the presence of bile salt concentration and their antagonistic activity against pathogenic bacteria. Investigation on probiotics study supported that they are beneficial to human beings and act as a barrier against pathogenic bacteria.

Probiotic Properties of Lactic Acid Bacteria Isolated from Traditional Yoghurt (Dahi) in Sindh Pakistan

The probiotic properties of Lactobacillus isolates of traditional yoghurt were investigated during the study. For that seven species of Lactobacillus were identified phenotypically. Out of 84 isolates, 23 acidophilus, 21 L. casei, 11 L. helveticus, 09 each L. delbrueckii sub sp. bulgaricus and L. delbrueckii sub sp. lactis, 03 L. viridescense and 02 L. plantarum were identified. All of these identified species were screened for antibacterial activity against foodborne pathogens, acid and bile tolerance and antibiotic resistance pattern. The results indicated that L. casei S66, L. delbrueckii sub sp. bulgaricus S65, L. acidophilus S26 and L. plantarum S19 produced antimicrobial substances against the indicator organisms and showed tolerance against acidic pH of 2.5 and survival against the bile salt concentration of 0.1 and 0.2. The L. acidophilus S26 survived the 0.3% bile salt concentration and was resistant to antibiotics ciprofloxacin, kanamycin, penicillin and vancomycin.

Effect of drying methods on Lactobacillus Rhamnosus GG microcapsules prepared using the complex coacervation method.

Lactobacillus rhamnosus GG (LGG) microcapsules prepared using the complex coacervation method were dried through spray and vacuum freeze drying. Physical properties, resistance to simulated gastrointestinal and bile salt conditions, and the stability of the LGG microcapsules during storage and heat treatment were estimated. Spray and vacuum freeze drying are suitable for LGG microcapsule preparation because of lower than 2.80% of the water content, and higher than 93.21% of the encapsulation efficiency. Under the simulated gastrointestinal condition, the survival rates of two kinds of microencapsulated LGG were over 96%. At 0.6% bile salt concentration, the survival rate of microencapsulated LGG subjected to spray drying was 110.89% higher than that of LGG subjected to vacuum freeze drying. In addition, the stability of the former was better than that of the latter during storage under low water activity condition (0.11). However, under high water activity condition (0.75), the two showed opposite results. The two kinds of microencapsulated LGG were completely inactivated after 4weeks in 0.75 of water activity. The survival counts of microencapsulated LGG had no significant difference at -18°C after 8weeks. After 8weeks at 25°C and 4°C, the survival loss of microencapsulated LGG through drying and vacuum freeze drying was approximately 2 and 1 log CFU/g, respectively. PRACTICAL APPLICATION: LGG is a kind of microorganism beneficial to the human body, but it is easy to inactivate and lose its physiological value. LGG microcapsules can improve the stability of LGG, prolong the release time, and expand its application range. The drying method will affect the properties of LGG microcapsules. So, the characteristics analysis of LGG microcapsules with different drying methods can provide a reference for the preparation and application of LGG microcapsules.

Understanding the Impact of Age-Related Changes in Pediatric GI Solubility by Multivariate Data Analysis.

The aim of this study was to understand drug solubilization as a function of age and identify drugs at risk of altered drug solubility in newborns and young infants in comparison to adults. Multivariate statistical analysis was used to understand drug solubilization as a function of drug’s physicochemical properties and the composition of gastrointestinal fluids. The solubility of seven poorly soluble compounds was assessed in adult and age-specific fasted and fed state biorelevant media. Partial least squares regression (PLS-R) was used to assess the influence of (i) drug physicochemical properties and (ii) age-related changes in simulated GI fluids, as well as (iii) their interactions, on the pediatrics-to-adult solubility ratio (Sp/Sa (%)). For five out of seven of the compounds investigated, Sp/Sa (%) values fell outside of the 80–125% limits in at least one of the pediatric media. Lipophilicity was responsible for driving drug solubility differences between adults and children in all the biorelevant media investigated, while drug ionization was most relevant in the fed gastric media, and the fasted/fed intestinal media. The concentration of bile salts and lecithin in the fasted and fed intestinal media was critical in influencing drug solubility, while food composition (i.e., cow’s milk formula vs. soy formula) was a critical parameter in the fed gastric state. Changes in GI fluid composition between younger pediatric patients and adults can significantly alter drug luminal solubility. The use of pediatric biorelevant media can be helpful to identify the risk of altered drug solubilization in younger patients during drug development.

Sterol bioaccessibility in a plant sterol-enriched beverage using the INFOGEST digestion method: Influence of gastric lipase, bile salts and cholesterol esterase

This study evaluates the influence of increasing bile salts and the addition of key enzymes of the lipidic metabolism in the INFOGEST digestion method on sterol bioaccessibility from a plant sterol (PS)-enriched beverage. The assayed modifications were increasing concentration of bovine bile salts (10 vs. 17.5 mM), and addition of gastric lipase (GL) (60U/mL), cholesterol esterase (CE) (0.075 or 2U/mL) or both. Compared to the original method (10 mM bile salts without enzymes), the assayed conditions significantly reduced bioaccessibility of individual (from 11.3 to 19.7 to 5.1–16.6%) and total PS (13.7 to 6.9–8.0%), and cholesterol (52.8 to 20.9–26.1%), except only when CE is added not allowing cholesterol quantification. The bioaccessibility achieved when lipolytic enzymes were tested was similar for all sterols. For a more physiological approach to in vivo conditions, incorporation of bile salts (10 mM), GL (60U/mL) and CE (0.075U/mL) to the INFOGEST method is proposed, although it increases the cost compared to the established method.

Cell-free culture supernatants of Lactobacillus spp. and Pediococcus spp. inhibit growth of pathogenic Escherichia coli isolated from pigs in Thailand

BackgroundPathogenic Escherichia coli (E. coli) is an important causative agent for infectious diseases in pigs and causes significant economic loss. The global concern of antimicrobial resistance of bacteria raises awareness of the alternative ways of using antimicrobial peptides (AMPs). The study was aimed to identify and test the efficacy of AMPs from Lactobacillus spp. against the growth of pathogenic E. coli isolated from pigs in Thailand. Briefly, cell-free culture supernatants (CFCS) from 3 strains of lactic acid bacteria (LAB) consisting of Lactobacillus acidophilus (strain KMP), Lactobacillus plantarum (strain KMP), and Pediococcus pentosaceus (strain KMP) were tested against pathogenic E. coli via agar well diffusion assay in quadruplicates. The presence of a zone of inhibition (ZOI) around wells was evaluated at different incubation time. Acid and bile tolerance test was performed for bacterial viability in acid and bile salt conditions. In addition, LAB cross-streaking assay was evaluated for antagonist activity.ResultsThe study showed that CFCS from L. acidophilus KMP, L. plantarum KMP, and P. pentosaceus KMP could inhibit the growth of pathogenic E. coli isolated from pigs in a time-dependent manner. To exemplify, the ZOI of L. plantarum KMP against E. coli (ETEC) at 8, 10, 12, 14, and 16 h incubation, were 26.6 ± 1.1, 24.9 ± 1.9, 22.5 ± 2.4, 20.3 ± 2.9, and 17.9 ± 3.3 mm, respectively. The ZOI was significantly different between 8, 10, 12, 14 h incubation, and the ZOI of the CFCS from L. plantarum KMP was larger than others (P-value < 0.05). Furthermore, L. acidophilus KMP, L. plantarum KMP, and P. pentosaceus KMP showed viability in pH 3.0, 0.3, and 0.5% (w/v) bile salt concentration. They exhibited no antagonist activity among each other.ConclusionsAccording to the results, the CFCS from LAB including L. acidophilus KMP, L. plantarum KMP and P. pentosaceus KMP can inhibit the growth of pathogenic E. coli, isolated from pigs in Thailand. The antimicrobial activity observed was incubation time dependent.

Effects of Bacillus amyloliquefaciens TL106 Isolated from Tibetan Pigs on Probiotic Potential and Intestinal Microbes in Weaned Piglets.

ABSTRACTBacillus amyloliquefaciens is a nonpathogenic microorganism whose highly active amylase is widely isolated from soil and plants. TL106 is an isolate of Bacillus amyloliquefaciens isolated from cold- and disease-resistant Tibetan pigs in Linzhi, Tibet. Here, we report that TL106 not only could survive in acidic environments, high bile salt concentrations, and high-temperature conditions but also was resistant to antibiotics. It significantly improved the growth performance of weaned piglets, especially in the prevention of diarrhea. The crude fiber and crude ash digestibility in weaned piglets after TL106 administration was considerably higher than that in other groups. The results of 16S rRNA sequencing conveyed that TL106 stabilized gut microbiota that was disturbed by the weaning process with an increased level of Lachnospiraceae, Peptococcaceae.rc4_4, Erysipelotrichaceae.L7A_E11, and Mollicutes.RF39. Hence, this study proved that Bacillus amyloliquefaciens TL106 might be a candidate for antibiotics in Duroc×Landrace×Yorkshire weaned piglets.IMPORTANCE Antibiotics are often used to promote animal growth and prevent diarrhea in weanling piglets. Nevertheless, intestinal pathogenic bacterial resistance and drug residues caused by antibiotic overuse are worthy of concern and demand an urgent solution. Bacillus amyloliquefaciens TL106 has been isolated from cold- and disease-resistant Tibetan pigs in Linzhi, Tibet. It significantly improved the growth performance, decreased diarrhea, increased the absorption of crude substances, and regulated the gut flora homeostasis in Duroc×Landrace×Yorkshire weaned piglets. As an antibiotic candidate, TL106 perfectly displayed its probiotic potential and pollution-free properties.