Bile Salt Concentration Research Articles

The Use of Global Sensitivity Analysis to Assess the Oral Absorption of Weakly Basic Compounds: A Case Example of Dipyridamole.

To utilize the global system analysis (GSA) in oral absorption modeling to gain a deeper understanding of system behavior, improve model accuracy, and make informed decisions during drug development. GSA was utilized to give insight into which drug substance (DS), drug product (DP), and/or physiological parameter would have an impact on peak plasma concentration (Cmax) and area under the curve (AUC) of dipyridamole as a model weakly basic compound. GSA guided the design of in vitro experiments and oral absorption risk assessment using FormulatedProducts v2202.1.0. The solubility and precipitation profiles of dipyridamole in different bile salt concentrations were measured. The results were then used to build a mechanistic oral absorption model. GSA warranted further investigation into the precipitation kinetics and its link to the levels of bile salt concentrations. Mechanistic modeling studies demonstrated that a precipitation-integrated modeling approach appropriately predicted the mean plasma profiles, Cmax, and AUC from the clinical studies. This work shows the value of GSA utilization in early development to guide in vitro experimentation and build more confidence in identifying the critical parameters for the mathematical models.

Thermodynamics of doxorubicin - bile salt association: An investigation based on isothermal titration calorimetry

Association of doxorubicin (DOX), a positively charged anthracycline, with bile salts (sodium cholate, NaC; sodium deoxycholate, NaDC, and sodium taurodeoxy cholate, NaTDC) has been studied by isothermal titration calorimetry (ITC). These bile salts form micelles in physiological conditions, and subsequent micellization parameters vary in accordance to their hydrophobicity. In this study, we show that thermodynamics of micellization of bile salts can be modulated via incorporation of DOX and changes in solution temperature. DOX incorporation was accompanied with reduction in critical micelle concentration (CMC) of bile salts. This was mediated through expulsion of structured water from the hydrophobic part of bile salt, and it was verifiable from the appearance of additional thermodynamic events in demicellization process. Interestingly, free energy of bile salts increased upon adding DOX which is suggestive of loss in the spontaneity of their micellization following this association. We assert that micelle formation in case of bile salt – DOX complex may not have occurred instantly. Instead, it was preceded by a bile salt - DOX equilibrium as a result of changes in the interfacial characteristics of bile salts in question.

Assessment of Inter-Individual Pharmacokinetic Variability of Voriconazole Based on Bile Salt Disparities using POP-PK Modeling

Background and Objectives: Voriconazole is a powerful biopharmaceutics classification system (BCS) class II antifungal agent with vast inter-individual pharmacokinetic variability. Bile salts have recently emerged as potential contributors to such variations. Based on population PK modeling and in-vitro biorelevant dissolution investigations, the current study intends to evaluate the inter-individual variability of voriconazole in pediatrics. Methods: All models were developed using PK-Sim software. A simulated population consisting of 100 pediatric individuals was established following the baseline model development. Further, experimentally obtained in-vitro dissolution data of voriconazole based on the bile salt differences representing different pediatric age groups were incorporated into a qualified pediatric model. Simulated plasma concentration-time profiles were then evaluated by comparing model-predicted parameters with that of the baseline model to draw inferences. Result: Each model was created and validated successfully. The pediatric subjects were shown to have larger inter-individual variability than adult subjects. Additionally, simulations based on individual parameter estimations from the final model showed that after administering a 4 mg/kg peroral dose of voriconazole, the anticipated Cmax values of the adult model were within a two-fold range compared to that of the pediatric model. However, upon comparison, the model-predicted population pk profiles of children, infants, and neonates showed minimal variations in the Cmax values. Conclusion: In pediatrics, voriconazole inter-individual variability was significantly influenced by the concentration of gut bile salts. Furthermore, the present research can be carried forward along with population PK modeling and sufficient clinical data for dose recommendations in special populations as well as in diseased conditions.

Characterizing interregional differences in the rheological properties and composition of rat small intestinal mucus.

The mucus layer in the small intestine is generally regarded as a barrier to drug absorption. However, the mucus layer is a complex system, and presently, only a few studies have been conducted to elucidate its physicochemical properties. The current study hypothesizes that the mucus layer contains solubility-enhancing surfactants and thus might aid the oral absorption of poorly water-soluble drugs.Mucus was sampled from sections of the small intestine of fasted rats to analyze the rheological properties and determine the mucus pH and concentrations of proteins and endogenous surfactants, i.e., bile salts, polar lipids, and neutral lipids.The mucus layer in the two proximal sections of the small intestine exhibited different rheological properties such as higher zero-shear viscosity and lower loss tangent and higher protein concentrations compared to all subsequent sections of the small intestine. The pH of the mucus layer was stable at ~ 6.5 throughout most of the small intestine, but increased to 7.5 in the ileum.The bile salt concentrations increased from the duodenum (16.0 ± 2.2mM) until the mid jejunum (55.1 ± 9.5mM), whereas the concentrations of polar lipids and neutral lipids decreased from the duodenum (17.4 ± 2.2mM and 37.8 ± 1.6mM, respectively) until the ileum (4.8 ± 0.4mM and 10.7 ± 1.1mM, respectively).In conclusion, the mucus layer of the rat small intestine contains endogenous surfactants at levels that might benefit solubilization and absorption of orally administered poorly water-soluble drugs.

Bacillus halotolerans SW207 alleviates enterotoxigenic Escherichia coli-induced inflammatory responses in weaned piglets by modulating the intestinal epithelial barrier, the TLR4/MyD88/NF-κB pathway, and intestinal microbiota.

Enterotoxigenic Escherichia coli (ETEC) is one of the major pathogens contributing to piglet diarrhea, with significant implications for both piglet health and the economic aspects of the livestock industry. SW207 is an isolate of Bacillus halotolerans isolated from the cold- and disease-resistant Leixiang pigs in Northeastern China. We have discovered that SW207 can survive in the pig's gastrointestinal fluid and under conditions of high bile salt concentration, displaying potent antagonistic activity against ETEC. In this study, we established a weaned piglet diarrhea model infected with ETEC to investigate the role of SW207 in preventing diarrhea and improving intestinal health. Results indicate that SW207 upregulates the expression of tight junction proteins, including claudin-1, occludin, and zonula occludens-1, at both the transcriptional and translational levels. Furthermore, SW207 reduces serum endotoxin, D-lactic acid, and various oxidative stress markers while enhancing piglet mechanical barrier function. In terms of immune barrier, SW207 suppressed the activation of the TLR4/MyD88/NF-κB pathway, reducing the expression of various inflammatory factors and upregulating the expression of small intestine mucosal sIgA. Concerning the biological barrier, SW207 significantly reduces the content of E. coli in the intestines and promotes the abundance of beneficial bacteria, thereby mitigating the microbiota imbalance caused by ETEC. In summary, SW207 has the potential to prevent weaned piglet diarrhea caused by ETEC, alleviate intestinal inflammation and epithelial damage, and facilitate potential beneficial changes in the intestinal microbiota. This contributes to elucidating the potential mechanisms of host-microbe interactions in preventing pathogen infections.IMPORTANCEEnterotoxigenic Escherichia coli (ETEC) has consistently been one of the significant pathogens causing mortality in weaned piglets in pig farming. The industry has traditionally relied on antibiotic administration to control ETEC-induced diarrhea. However, the overuse of antibiotics has led to the emergence of drug-resistant zoonotic bacterial pathogens, posing a threat to public health. Therefore, there is an urgent need to identify alternatives to control pathogens and reduce antibiotic usage. In this study, we assessed the protective effect of a novel probiotic in a weaned piglet model infected with ETEC and analyzed its mechanisms both in vivo and in vitro. The study results provide theoretical support and reference for implementing interventions in the gut microbiota to alleviate early weaned piglet diarrhea and improve intestinal health.

Tofu Whey-Based Media for Probiotic Lactiplantibacillus plantarum D4 as a Halal Starter Culture

In recent years, the development of probiotic-based fermented products with halal status has been a concern. The use of growth medium has relied on de Man Rogosa and Sharpe (MRS) as a relatively expensive standard medium, and its halal status is still uncertain. Extensive research has been carried out to investigate the development of low-cost halal alternative media for the cultivation of probiotic lactic acid bacteria (LAB). This study aimed to develop a probiotic halal and low-cost culture medium using a tofu whey-based medium. This study used three tofu whey-based media – A (tofu whey 100%), B (tofu whey 94.5%, molasses 3%, skim milk 2.5%), C (tofu whey 92.5%, molasses 3%, cheese whey 2.5%, tomato extract 2%), and MRS broth as a standard medium. Bacterial populations, total sugars utilized, total lactic acids produced, low pH (2.0) tolerance, and high bile salt concentration (oxgall 1.5%) were assayed. The highest bacterial population after 48 h of incubation was shown by medium B compared to medium MRS (12.34 ± 0.87 and 11.48 ± 0.3 log CFU/mL). Total sugars utilized by 48.28 ± 2.89, 38.89 ± 6.94, 39.14 ± 4.24, and 76.00 ± 1.41 %; on the other hand, total lactic acids produced by 0.16 ± 0.12, 0.03 ± 0.04, 0.31 ± 0.03, and 2.25 ± 1.48 % in A, B, C, and MRS, respectively. Probiotic tolerance at low pH and the presence of bile salts of Lactiplantibacillus plantarum D4 consistently showed a high survival rate in medium B compared to MRS. Based on these results, the components and proportions used in medium B were suitable for the growth of L. plantarum D4 as a halal probiotic starter candidate.

Insight into the Effect of Submicellar Concentrations of Sodium Deoxycholate on the Structure, Stability, and Activity of Bovine and Human Serum Albumin: An Interesting Comparison between Single and Double Tryptophan Proteins.

The progressive escalation in the applications of bile salts in diverse fields has triggered research on their interaction with various biological macromolecules, especially with proteins. A proper understanding of the interaction process of bile salts, particularly in the lower concentrations range, with the serum albumin seems important since the normal serum concentration of bile salts is approximately in the micromolar range. The current study deals with a comprehensive and comparative analysis of the interaction of submicellar concentrations of sodium deoxycholate (NaDC) with two homologous transport proteins: bovine serum albumin (BSA) and human serum albumin (HSA). HSA and BSA with one and two tryptophans, respectively, provide the opportunity for an interesting comparison of tryptophan fluorescence behavior on interaction with NaDC. The study suggests a sequential interaction of NaDC in three discrete stages with the two proteins. A detailed study using warfarin and ibuprofen as site markers provides information about the sites of interaction, which is further confirmed by inclusive molecular dynamics simulation analysis. Moreover, the comparison of the thermodynamics and stability of the NaDC-serum albumin complexes confirms the stronger interaction of NaDC with BSA as compared to that with HSA. The differential interaction between the bile salt and the two serum albumins is further established from the difference in the extent of decrease in the esterase-like activity assay of the proteins in the presence of NaDC. Therefore, the present study provides important insight into the effect of submicellar concentrations of NaDC on the structure, stability, and activity of the two homologous serum albumins and thus can contribute not only to the general understanding of the complex nature of serum albumin-bile salt interactions but also to the design of more effective pharmaceutical formulations in the field of drug delivery and biomedical research.

Evaluation of types and concentration of bile salts impact on physical properties of nisoldipine-loaded bilosomes

Background: Bilosomes are lipid vesicles that exhibit flexibility and deformability. They consist of phospholipids and amphiphilic bile salts. Compared to the normal vesicular systems such as liposomes and niosomes, bilosomes provide several notable advantages, including simplified manufacturing, cost-effectiveness, and enhanced stability. Aim: The main objective of the present work was to evaluate the effect of different bile salts on the physical properties that include entrapment efficiency, vesicle size, and polydispersity index(PDI). In addition, in vitro drug release for nisoldipine (NSD) loaded bilosomes was evaluated. Methods: Nisoldipine-loaded bilosomes were made using a thin film hydration technique. Cholesterol along with surfactant (span 60) was employed, and the formulation also contained several different bile salts, including sodium deoxycholate (SDC), sodium glycocholate (SGC), and sodium taurocholate (STC). Results: The developed NSD bilosomes exhibited an entrapment efficiency ranging from 44.2 ± 0.3 to 82.36 ± 0.80% and a vesicle size diameter in the nanometric dimensions (166 ± 1.83 to 237.8 ± 3.3 nm). An in-vitro release study revealed that formulas prepared with SDC bile salts showed higher drug release than SGC and STC formulas. Increasing the bile salt amount from 5 mg to 10 mg increases entrapment efficiency with increasing vesicle size. Further increase in bile salt led to decreased entrapment efficiency with increased vesicle size. SDC gives the best result in terms of entrapment efficiency and acceptable size. STC provides the largest particle size due to its high molecular weight compared to SGC and SDC. Conclusion: The SDC bile salt component is better suited for manufacturing NSD bilosomes. This is because this component yields the best results regarding high entrapment efficiency, nano size, and prolonged drug release.

Evaluation of the probiotic potential of yeast isolated from kombucha in New Zealand

The current study investigated the in vitro probiotic potential of yeast isolated from kombucha, a tea beverage fermented with a symbiotic culture of acetic acid bacteria and yeast. A total of 62 yeast strains were previously isolated from four different commercial kombucha samples sold in New Zealand. Fifteen representative isolates belonging to eight different species were evaluated for their growth under different conditions (temperature, low pH, concentrations of bile salts, and NaCl). Cell surface characteristics, functional and enzymatic activities of the selected strains were also studied in triplicate experiments. Results showed that six strains (Dekkera bruxellensis LBY1, Sachizosaccharomyces pombe LBY5, Hanseniaspora valbyensis DOY1, Brettanomyces anomalus DOY8, Pichia kudraivzevii GBY1, and Saccharomyces cerevisiae GBY2) were able to grow under low-acid conditions (at pH 2 and pH 3) and in the presence of bile salts. This suggests their potential to survive passage through the human gut. All 15 strains exhibited negative enzymatic activity reactions (haemolytic, gelatinase, phospholipase, and protease activities), and thus, they can be considered safe to consume. Notably, two of the fifteen strains (Pichia kudraivzevii GBY1 and Saccharomyces cerevisiae GBY2) exhibited desirable cell surface hydrophobicity (64.60–83.87%), auto-aggregation (>98%), co-aggregation, resistance to eight tested antibiotics (ampicillin, chloramphenicol, colistin sulphate, kanamycin, nalidixic acid, nitrofurantoin, streptomycin, and tetracycline), and high levels of antioxidant activities (>90%). Together, our data reveal the probiotic activities of two yeast strains GBY1 and GBY2 and their potential application in functional food production.

Isolation, identification, and potentiality of gut-derived probiotic bacteria from Heteropneustes fossilis, stinging catfish

Objective: This study was conducted to isolate and identify probiotic bacteria from wild stinging catfish (Heteropneustes fossilis), a very popular high-valued aquaculture species of Bangladesh. The isolates were identified through conventional culture-based and molecular techniques. Materials and Methods: Stinging catfish harvested from natural sources of three sampling sites under two districts (Kishoreganj and Netrakona) were collected, dissected for gut content, and cultured onto Lactobacillus MRS Agar plates. Out of 60 bacterial isolates obtained, 10 were cho¬sen for an in vitro evaluation of their probiotic potentials through pH and bile tolerance tests. The 16S rRNA gene sequences of the selected isolates were searched against the NCBI database using the Basic Local Alignment Search Tool for Nucleotides (BLASTNs). Results: The isolates were identified as Staphylococcus arlettae, Bacillus subtilis, Staphylococcus succinus, Bacillus velezensis, Kocuria subflava, Macrococcus caseolyticus, Lysinibacillus sphaeri¬cus, Glutamicibacter mysorens, Bacillus cereus, and Acinetobacter lwoffii. Among them, B. subtilis, S. succinus, B. velezensis, M. caseolyticus, G. mysorens, and B. cereus exhibited notable growth across all tested pH levels (pH 2, 3, and 4) and bile salt concentrations (0.3%, 0.5%, and 1.0%) sug¬gesting that they have strong potential as probiotic bacteria. In addition, S. arlettae also indicated promising growth except at pH 2. L. sphaericus and K. subflava exhibited limited growth at low pH but tolerated bile salt concentrations. A. lwoffii did not show any growth at pH tests but minimal growth at the lower concentrations of bile salts. Conclusion: According to the potentiality assessments and previous literature reviews, five iso¬lates such as B. subtilis, S. succinus, M. caseolyticus, G. mysorens, and B. cereus were identified as potential probiotic bacteria. As species-specific probiotics are considered to perform more effec¬tively and efficiently than unknown-sourced commercial probiotics, the findings of this study will be applicable in enhancing the aquaculture production of stinging catfish.

Identification of new yeast strains, Candida zeylanoidesY12‐3 and Hyphopichia pseudoburtoniiY12‐1, from the intestinal tract of rainbow trout, Oncorhynchus mykiss, with potential probiotic characteristics

AbstractIn this study, 2 yeasts, Candida zeylanoides isolate Y12‐3 (MN073455.1) and Hyphopichia pseudoburtonii isolate Y12‐1 (MN073489.1), were isolated from rainbow trout hindguts. Their identity was confirmed by amplification of internal transcribed spacer (ITS) gene regions. Their in vitro probiotic properties showed that they were hydrophobic and did not inhibit bacterial growth. However, they displayed positive co‐aggregation with several bacterial pathogens. It was interesting that Y12‐1 and Y12‐3 isolates survived and grew well in bile salt concentrations ranging from 0.6% to 1.5% and at low pH conditions. After a 35‐day feeding trial, the results of dietary incorporation of the yeast isolates showed that serum myeloperoxidase activity was unchanged in the treated and control groups. Meanwhile, serum lysozyme activity in yeast groups was decreased significantly compared to the control. However, fish fed with Y12‐1 had higher total protein, albumin, and globulin than other groups. Total cholesterol levels were decreased significantly in yeast groups compared to the control. Interestingly, the Y12‐1 and Y12‐3 groups showed higher survival (69.05% and 80.95%) after the challenge with Lactococcus garvieae compared to the control (45.24%). In brief, the aforementioned findings showed that Y12‐1 and Y12‐3 strains could be potential probiotic candidates for use in rainbow trout farming.

Molecular identification and safety assessment of the potential probiotic strain Bacillus paralicheniformis HMPM220325 isolated from artisanal fruit dairy products.

Bacillus probiotics exhibit considerable economic potential owing to their heightened resilience to external stressors and relatively lower costs related to production and preservation. Although Bacillus paralicheniformis has been acknowledged as a plant-promoting bacterium for a long time, understanding its potential as a probiotic is still in its nascent stages. In this study, the safety and probiotic characteristics of a strain of HMPM220325, isolated from artisanal fruit dairy products, were examined through whole-genome sequencing and phenotypic analysis. The whole genome of HMPM220325 was analyzed for antimicrobial resistance genes, pathogenicity factors, and genes associated with probiotic traits including stress resistance, spore formation, gut adhesion, competitive exclusion of pathogens, bacteriocin expression, and carbohydrate metabolism related to prebiotic utilization. Also, wet lab experiments were conducted for the characterization of probiotics. The identification of the organism as B. paralicheniformis was verified. Its safety was assessed through in silico analysis, the haemolytic activity test, and the acute oral toxicity test. B. paralicheniformis HMPM220325 demonstrated its ability to survive in the pH range of 4-10 and bile salt concentrations of 0-0.9% (w/v), tolerate temperatures between 20 and 60 °C, and exhibit a robust antioxidant capacity. Moreover, B. paralicheniformis HMPM220325 demonstrated a moderate level of hydrophobicity, had the ability to form biofilms, achieved a self-aggregation rate of 51.77 ± 1.01% within 6 hours, and successfully colonized the mouse intestine for a duration of up to 17 days. Additionally, the genome of B. paralicheniformis HMPM220325 contains three gene clusters associated with the biosynthesis of bacteriocins and exhibits co-aggregation with Staphylococcus aureus, Pseudomonas aeruginosa, and Salmonella enterica serovar Typhimurium. The findings of the genomic analysis align with those obtained from the experimental investigation, thereby substantiating the potential of B. paralicheniformis HMPM220325 as a probiotic suitable for incorporation in dairy functional foods and feed applications.

Evaluation of viability and survival of free and maltodextrin microencapsulated Bifidobacterium animalis subsp. animalis through spray-drying process

Bifidobacterium animalis subsp. animalis is a microorganism integrated into the human intestinal microbiota and performs a probiotic function through mechanisms that promote the absorption of nutrients, the modulation of the immune system, and the production of lactic acid, among other aspects. Microencapsulation using maltodextrin promotes the protection of microorganisms against physical and chemical factors, improving viability over time. Bifidobacterium animalis subsp. animalis was microencapsulated through spray-drying using maltodextrin. Survival under pH conditions, bile salts, and temperature were evaluated as well as its viability during storage conditions. The viability of the encapsulated agent stored at 25 °C remained high and constant during the first three weeks. The results for free and microencapsulated thermal tolerance showed an important difference among survival percentages of each tested temperature, and microencapsulation showed a protective effect against temperatures like or lower than 55 °C. Regarding pH 2.5 exposure for 3h, there is a survival of 5.38% for free microorganisms in contrast to 11.87% for encapsulated, whereas in a pH 3.5 for 3h, the encapsulated agent showed a survival of 23%. The results obtained from encapsulated cells stressed with a 1g/L concentration of bile salts showed a survival of 19%, while free cells presented a total loss of viability when subjected for 3h at the same concentration. Microencapsulated Bifidobacterium animalis subsp. animalis demonstrated potential for its use incorporated into foods, but it is necessary to improve viability conditions during storage and survival under gastric stress conditions.

Optimization of Enterocin Production from Probiotic Enterococcus faecium Using Taguchi Experimental Design.

Enterocin is a significant broad-spectrum peptide antibiotic produced by Enterococcus faecium (E. faecium). Enterocin production by E. faecium was investigated using the Taguchi experimental design. The Taguchi models were used to save the time and effort required for optimizing the different conditions affecting its production. They were applied to optimize the conditions for enterocin production using the least number of experiments and the least number of required materials. Seven factors i.e., pH, temperature, time of incubation, aeration rate, inoculum size, carbohydrate concentration, and bile salt concentrations, each at three levels were selected and an orthogonal array layout of L273 was performed. The experimental results indicated that the best incubation conditions were; 48 hours incubation on a nutrient medium at pH 6.5, temperature at 25 °C, aeration rate at 0 round per minute, inoculum size 20 mL, and bile salt concentration. It was 5%, and the carbon concentration was 2.0%. All these factors combined led to the best enterocin production by E. faecium. This optimization of enterocin production by the Taguchi experimental models emphasized some important results regarding the interaction of the different driving factors leading to the best enterocin production in one experiment.

Development, optimization, and assessment of losartan nano-bilosomes to mitigate diabetes-induced microvascular complications in Sprague Dawley rats

Losartan has a significant renal protection effect in type 2 diabetic patients. It was loaded into bilosomes to overcome its low oral bioavailability and improve its renal protective effects. The bilosomes were optimized using a 23 factorial design. Bile salt type and concentration and phospholipid concentration influenced the vesicles percent drug entrapment efficiency (%EE), vesicle size (VS), polydispersity index (PDI) and zeta potential (ZP). The %EE varied from 71.73 ± 0.91 % to 92.34 ± 0.75 %. VS varied from 146.87 ± 3.56 to 286.29 ± 1.72 nm while PDI ranged from 0.28 ± 0.02 to 0.46 ± 0.03. ZP was high enough (−28.34 ± 0.61 to −35.64 ± 1.38 mV) to afford colloidal stability to the bilosomes. The bilosomes had the ability to prolong the release of the drug, with the percentage of losartan released after 12 h ranging from 64.31 ± 1.03 % to 88.48 ± 0.93 %. An optimized formulation was selected and used orally in an in vivo diabetic nephropathy rats model to study its ability to improve losartan nephroprotective effects. The diabetic group exhibited elevated serum creatinine, blood urea nitrogen (BUN), urine albumin, and inflammatory cytokines. Losartan bilosomes demonstrated reduced BUN and proteinuria compared to the free drug. Additionally, they outperformed the free drug in enhancing kidney function, preserving renal cellular structure, and mitigating diabetic renal inflammation and fibrosis. This was evidenced by significantly lower levels of tumor necrosis factor-alpha, interleukin-6, nuclear factor kappa, and macrophage markers. These findings conclusively demonstrate the promising potential of losartan bilosomes as an effective oral formulation to mitigate diabetic nephropathy.

Selection and evaluation of lactic acid bacteria from chicken feces in Thailand as potential probiotics.

Lactic acid bacteria (LAB) are widely used as probiotics in poultry production due to their resilience to low pH and high bile salt concentrations, as well as their beneficial effects on growth performance and antagonistic activity against enteric pathogens. However, the efficacy of probiotics depends on strain selection and their ability to colonize the host's intestine. This study aimed to select, identify, and evaluate LAB strains isolated from chicken feces in Thailand for potential use as probiotics in the chicken industry. LAB strains were isolated from 58 pooled fresh fecal samples collected from chicken farms in various regions of Thailand, including commercial and backyard farms. Gram-positive rods or cocci with catalase-negative characteristics from colonies showing a clear zone on MRS agar supplemented with 0.5% CaCO3 were identified using MALDI-TOF mass spectrometry. The LAB isolates were evaluated for acid (pH 2.5 and pH 4.5) and bile salt (0.3% and 0.7%) tolerance. Additionally, their cell surface properties, resistance to phenol, antimicrobial activity, hemolytic activity, and presence of antimicrobial resistance genes were determined. A total of 91 LAB isolates belonging to the Pediococcus, Ligilactobacillus, Limosilactobacillus, and Lactobacillus genera were obtained from chicken feces samples. Backyard farm feces exhibited a greater LAB diversity compared to commercial chickens. Five strains, including Ligilactobacillus salivarius BF12 and Pediococcus acidilactici BF9, BF14, BYF20, and BYF26, were selected based on their high tolerance to acid, bile salts, and phenol. L. salivarius BF12 and P. acidilactici BF14 demonstrated strong adhesion ability. The five LAB isolates exhibited significant cell-cell interactions (auto-aggregation) and co-aggregation with Salmonella. All five LAB isolates showed varying degrees of antimicrobial activity against Salmonella strains, with P. acidilactici BYF20 displaying the highest activity. None of the LAB isolates exhibited beta-hemolytic activity. Whole genome analysis showed that L. salivarius BF12 contained ermC, tetL, and tetM, whereas P. acidilactici strains BF9 and BF14 carried ermB, lnuA, and tetM. The selected LAB isolates exhibited basic probiotic characteristics, although some limitations were observed in terms of adhesion ability and the presence of antibiotic resistance genes, requiring further investigation into their genetic location. Future studies will focus on developing a probiotic prototype encapsulation for application in the chicken industry, followed by in vivo evaluations of probiotic efficacy.

Enzymatic prodrug degradation in the fasted and fed small intestine: In vitro studies and interindividual variability in human aspirates

The aim of the current study was (1) to develop an automation-based protocol for in vitro assessment of enzymatic drug stability at fasted- and fed-state intestinal conditions, (2) to characterize the inter-individual variability of drug degradation in fasted- and fed-state human intestinal fluids, and (3) to compare the obtained in vitro results to drug degradation in human intestinal fluids by taking variability into account. In human intestinal fluids, drug degradation displayed large inter-individual variability, with coefficients of variance generally ranging between 30 and 70 %. The effect of food on the inter-individual variability was highly dependent on the type of drug. The increase of pH in the range between 5.0 and 7.0 significantly accelerated the degradation rate of the studied drugs both in the in vitro and ex vivo experiments. In contrast, the increase of bile salt and phospholipid concentrations in the in vitro screen decreased strongly the degradation rate of the hydrophobic drugs. The developed automated in vitro screen mimicked relatively well the ex vivo degradation of all drugs in the fasted state, whereas in the fed state the degradation of only one of the drugs was adequately reproduced.

Evaluating Enterococcus faecium9 N-2 as a probiotic candidate from traditional village white cheese.

In this study, various functional and probiotic attributes of the Enterococcus faecium 9 N-2 strain isolated from village-style white cheese were characterized, while also assessing its safety. To achieve this, we conducted an invitro analysis of several key probiotic properties exhibited by the 9 N-2 strain. Notably, this strain demonstrated robust resilience to low pH, high bile salt concentrations, lysozyme, pepsin, pancreatin, and phenol. Furthermore, this strain displayed exceptional auto-aggregation capabilities and moderate co-aggregation tendencies when interacting with Escherichia coli. The cell-free supernatant derived from strain 9 N-2 exhibited significant antimicrobial activity against the tested pathogens. The strain exhibited resistance to gentamicin, meropenem, and bacitracin, while remaining susceptible to vancomycin and various other antibiotics. Furthermore, it was found that E. faecium 9 N-2 possessed the capacity to produce the phytase enzyme. When all the results of this study are evaluated, it is thought that 9 N-2 strain has superior probiotic properties, and therefore it can be used as probiotic in food, medicine, and animal feed in the future. In addition, further invivo tests should be performed to fully understand its effects and mechanisms of action and to confirm its safety and probiotic effects. Further research and clinical trials are also needed to identify new strains with potential probiotic properties.

Survivability of probiotics in Pickering emulsion gels stabilized by salmon by-product protein / sodium alginate soluble complexes at neutral pH

Adequate amounts of live probiotics reaching the gut are necessary to maintain host health. However, the harsh environment during processing, the low pH of human gastric acid, and the high concentration of bile salts in the gut can significantly reduce survivability of probiotics. In this work, we propose a simple Pickering emulsion gels strategy to encapsulate Lactobacillus plantarum Lp90 into oil droplets filled in calcium alginate gels to improve its viability under pasteurization and gastrointestinal conditions. The emulsion gels were stabilized by the soluble complexes of salmon by-product protein (SP) and sodium alginate (ALG), and the aqueous phase was solidified by the addition of calcium. The interaction between SP and ALG and the effect of ALG concentration on emulsifying ability and emulsion stability were studied. The results from optical imaging, nuclear magnetic resonance, and rheological properties showed that the stability and viscosity of the emulsions gradually increased with the increased ALG concentration, while the droplet size of the emulsions and the content of free water in the system decreased significantly. Especially when the concentration of ALG was 1 %, the emulsion system was stable under the environment of high temperature and high ionic strength, and the water holding capacity was the highest. Through pasteurization and gastrointestinal digestion experiments, it was found that the survival rate of probiotics encapsulated in emulsion gels was significantly higher than that encapsulated in emulsions or hydrogels, which benefited from the dual action of oil droplets and calcium alginate gels network. These results provide a new strategy for the processing of probiotics and the high-value utilization of marine fish by-products.

Impact of prandial state on luminal and permeation-behavior of fosamprenavir oral suspension studied by in vitro tools: Solubility-, bioconversion- and permeation- studies in biomimetic media

Fosamprenavir is a prodrug designed to overcome the solubility challenge of the parent drug amprenavir, a protease inhibitor. For the marketed oral suspension (Telzir®) a clinically documented negative food effect has been reported.The present study aims to gain a better mechanistic understanding of the food effect by in vitro tests on solubility, bioconversion, permeability, and dynamic dissolution/bioconversion/permeation studies in a high throughput manner on a microtiter plate (Permeapad® Plate). In order to mimick luminal condition changes in connection with food, various modified versions of fasted and fed state simulated intestinal fluids (FaSSIF-V2) and (FeSSIF–V2) were used. The kinetics of enzymatic cleavage (simulated bioconversion) were studied in these media with a focus on molecularly dissolved drug concentrations using microdialysis. Dynamic dissolution/bioconversion/permeation experiments, indicated the following factors to contribute to reduced permeation in fed state: elevated inorganic phosphate concentrations, higher concentrations of bile salts and lipids and lower intestinal pH. The impact of these effects is difficult to capture in vivo due to their interconnection and large variability between individuals.This study revealed factors leading to an altered luminal behavior of Telzir® oral suspension in fed state, which may contribute to explain the observed reduced amprenavir absorption from the suspension. Especially the high throughput small-scale dissolution/bioconversion/permeation experiments on a microtiter plate were demonstrated an efficient and powerful tool for elucidating the food effects of phosphate-ester prodrug type drug products as far as their altered luminal behavior is concerned.