Gastric Juice Tolerance Research Articles

Assessing the probiotic potential and safety of newly isolated Bacillus coagulans VHBAX‐04: in vitro and in silico evaluations

SummaryThe human gastrointestinal tract hosts a diverse and intricate microbial community, a pivotal contributor to human well‐being. An effective strategy for exploring the diversity and potential probiotic attributes of Bacillus species is to isolate them from faecal samples. In this investigation, we scrutinised the in vitro probiotic characteristics of Bacillus coagulans VHBAX‐04, an isolate derived from human faeces. These attributes encompassed acid and gastric juice tolerance, resistance to bile salts and intestinal juice, adhesion capabilities, safety profile, antibiotic resistance pattern, the absence of toxin genes, and antimicrobial efficacy. Furthermore, we conducted in silico analyses to evaluate its probiotic potential. The notable absence of genes associated with mucin degradation, red blood cell lysis, gelatin hydrolysis, or toxin production in B. coagulans VHBAX‐04 certifies its safety as a probiotic. Additionally, the distinct antibiotic resistance pattern of strain VHBAX‐04 suggests its potential for co‐administration with antibiotics. In conclusion, this study underscores the suitability of B. coagulans VHBAX‐04 as a viable probiotic option. Isolation and Evaluation of Bacillus coagulans WBX04: A Probiotic Strain from Human Feces Studied through 16S rRNA Sequencing and In Vitro Tests.

Rice-Based Alcoholic Fermented Beverages of North-East India: Insight into Ethnic Preparation, Microbial Intervention, Ethnobotany, and Health Benefits

Introduction. Alcoholic fermented rice-based beverages (AFRBs) have been used since time immemorial for spiritual connection and cultural rituals in North-East India. AFRBs are also used traditionally in the healthcare system for remedy of tiredness, digestion problems, hypertension, and diabetes. Problems Statement. Limited scientific documents are available on AFRBs including starter cake preparation, production of the beverages, microbial intervention, nutritional aspects, and health benefits. Objectives. This review has been undertaken to find insight into ethnic preparation, microbial intervention, ethnobotany, and health benefits as well as nutritional aspects of popular AFRBs of North-East India. Major Findings. Studies reveal that AFRBs are enriched with medicinal benefits due to the presence of various microflora and medicinal plants. The presence of medicinal plants plays an important role underlying the health benefits of AFRBs. In addition, several functional microorganisms, such as strains of Lactobacillus and yeast, enhance the therapeutic potential of the AFRBs. Interestingly, strains of Pediococcus and Lactobacillus spp. improve bile and gastric juice tolerance, hyperlipidemia, diabetes, obesity, and amylolytic activities and regulate the expression of fatty acid biosynthetic genes. Moreover, strains of Saccharomyces decrease the secretion of proinflammatory cytokines and alter the respective mRNA expression. Furthermore, the consumption of AFRBs has no harmful effect among the communities on a regular basis in normal diet. Conclusion. A detailed scientific approach is required to maintain the desired product quality of AFRBs for the upliftment of the socioeconomic status of North-East India.

Molecular Assessment and Validation of the Selected Enterococcal Strains as Probiotics.

Probiotics are live microorganisms which confer health benefits to the host. Lactic acid bacteria (LAB) are used as probiotics since decades. Enterococci being the member of LAB have proven probiotic strains; therefore, this study was aimed at finding out the potential probiotic candidates from the pool of locally isolated strains. For initial screening, one hundred and twenty-two strains were selected and subjected to different confirmatory and phenotypic tests to choose the best strains that have potential probiotic criteria, i.e., no potential virulence traits, antibiotic resistance, and having tolerance properties. Keeping this criterion, only eleven strains (n = 11) were selected for further assessment. All virulence traits such as production of hemolysin, gelatinase, biofilm, and DNase were performed and not found in the tested strains. The molecular assessment indicates the presence of few virulence-associated genes in Enterococcus faecalis strains with variable frequency. The phenotypic and genotypic assessments of antibiotic resistance profile indicate that the selected strain was susceptible to ten commonly used antibiotics, and there were no transferrable antibiotic resistance genes. The presence of CRISPR-Cas genes also confirmed the absence of antibiotic resistance genes. Various enterocin-producing genes like EntP, EntB, EntA, and EntQ were also identified in the selected strains which make them promising probiotic lead strains. Different tolerance assays like acid, NaCl, and gastric juice tolerance that mimic host conditions was also evaluated by providing artificial conditions. Cellular adhesion and aggregation properties like auto- and co-aggregation were also checked and their results reflect all in the favor of lead probiotic strains.

Chemical Characterization and Impact of Nipple Fruit (Solanum mammosum) on the Characteristics of Lactobacillus acidophilus LA K

Nipple fruit (Solanum mammosum) has been considered to have great pharmaceutical potential because of its high amounts of solamargine and solasonine. This study aimed to examine the effect of nipple fruit at different concentrations (0.5%, 1%, and 2% (w/v)) on the viability, acid, bile, lysozyme, and gastric juice tolerance, and protease activity of Lactobacillus acidophilus LA K. The viability was studied in MRS broth. Acid tolerance was determined by adjusting the pH to 2, whereas bile tolerance was examined with oxgall 0.3% (w/v) in MRS broth. Lysozyme resistance was investigated in an electrolyte solution with lysozyme (100 mg/L), while gastric juice tolerance was analyzed with pepsin and NaCl. Protease activity was determined spectrophotometrically at 340 nm in skim milk with o-phthaldialdehyde reagent. L. acidophilus LA K was incubated anaerobically (37 °C). Microbial growth was determined every 2 h for 10 h of incubation. Acid tolerance was determined at 0, 5, and 15 min, whereas bile tolerance was analyzed at 0, 4, and 8 h of incubation. Lysozyme tolerance was determined at 0, 1, and 2 h of incubation, while gastric juice tolerance was determined at pH 2, 3, 4, 5, and 7. Protease activity was evaluated at 0, 12, and 24 h incubation. Nipple fruit’s chemical and bioactive compounds were also examined to discuss their impact on the survival of L. acidophilus LA K. Nipple fruit did not affect microbial growth, bile, and acid tolerance. Nipple fruit at 2% had higher survivability on the simulated gastric juice and lysozyme resistance and increased protease activity.

Attributes of Lactobacillus acidophilus as Effected by Carao (Cassia grandis) Pulp Powder

This study aimed to examine the prebiotic effect of Carao (Cassia grandis) pulp powder on the probiotic characteristics of Lactobacillus acidophilus regarding the viability, enzymatic activity, lysozyme resistance, bile and acid tolerances, and tolerance to gastric juices. Carao powder was used at 0% (control), 1%, 2%, and 3% (w/v). Acid and lysozyme tolerance were determined at 0, 30, 60, 90, and 120 min of incubation, whereas bile tolerance was analyzed at 0, 4, and 8 h. The gastric juice tolerance was determined at pH 2, 3, 4, 5, and 7 during 0 and 30 min of incubation. The protease was evaluated at 0, 12, and 24 h of incubation. The bacterial viability experiment was carried out for 10 h, taking readings every hour. Low-acidity conditions were used, and no significant differences were found between the control and the different Carao concentrations added to the L. acidophilus viability study. The Carao samples at 2% and 3% had significantly (p < 0.05) higher counts for bile and lysozyme resistance and higher protease activity when compared to control samples. On the other hand, Carao addition did not impact bacterial viability, acid tolerance, and gastric juice resistance. Thus, Carao pulp powder at different concentrations could act as a prebiotic source to enhance the development of L. acidophilus during gastrointestinal digestion.

Isolation and characterization of potential probiotic lactic acid bacteria from traditional cheese

A total of 25 traditionally procured white cheese were collected from the Samsun region in Turkey. Selected physicochemical and microbiological characteristics of the cheese were screened via classical analysis and significant differences were detected between cheese samples. In this study, twelve lactic acid bacterial isolates with high antimicrobial activity from these cheeses were selected for further analysis. Isolated strains were identified and characterized by phenotypic and genotypic methods, and their probiotic and industrial properties were studied. Nine of the isolates were identified as enterococci (4 E. durans, 3 E. faecium, 1 E. faecalis and 1 E. gallinarum). Other identified strains included 2 Lactiplantibacillus pentosus, and 1 Loigolactobacillus coryniformis subsp. torquens. A series of established in vitro tests were conducted to determine the probiotic potential of isolates. These tests include bile and gastric juice tolerance, antibiotic resistance, ability to survive at different temperatures, pH ranges, and salt concentrations, acid-producing ability, proteolytic activity, β-galactosidase production, and the ability to produce gas from glucose. The results of the study suggested that the E. faecium S1113, E. durans S104, E. durans S1121, and E. durans S202 isolates have potential use as novel probiotic strains in the food industry.

The Prospects of Lactobacillus oris as a Potential Probiotic With Cholesterol-Reducing Property From Mother's Milk.

This experiment was conducted to characterize potential Lactobacillus spp. isolated from mother's milk and infant feces to obtain new and specific probiotic strains. In this study, seven ascendant strains were identified as Lactobacillus spp. based on their morphological characteristics and biochemical properties. Among them, only one (C-1) isolate was identified as Lactobacillus oris through BioLogTM identification. The study further investigated the isolate through probiotic potentiality tests such as pH and bile tolerance, NaCl tolerance test, gastric juice tolerance, antioxidant activity, resistance to hydrogen, reduction of sodium nitrate, antimicrobial activity, and antibiotic susceptibility test. The result showed that the strain is a potential probiotic based on probiotic capability. The identified strain was most acid-tolerant and retained around 80% viability for up to 4 h at pH 1.0 and 2.0. The isolate showed tolerance against up to 1.50% bile concentration and gastric juice and was able to grow 1–6% NaCl concentrations. Lactobacillus oris showed resistance to most antibiotics as well as antagonistic activity against the tested pathogen, good antioxidant properties, reduction of sodium nitrate and H2O2. The isolate exhibited good intestinal epithelial adhesion properties, and SDS page was performed for secreted protein analysis. Moreover, the strain showed promising cholesterol-lowering properties based on the cholesterol level. This present result indicates that L. oris has superior probiotic properties and can be regarded as a potential probiotic candidate.

A polyphasic approach to characterize Weissella cibaria and Weissella confusa strains.

To study Weissella cibaria and Weissella confusa strains, lactic acid bacteria (LAB) members naturally present in food products, but not yet included in Qualified Presumption of Safety (QPS) list of European Food Safety Authority (EFSA). We carried out a comparative genome analysis of 23 sequenced W. cibaria and 7 W. confusa genomes, in parallel with a physiological and functional characterization of several strains previously isolated from sourdough-like maize bran fermentation. The genome analysis revealed the absence of dedicated pathogenicity factors. Some putative virulence genes found in Weissella genomes were also present in other LAB strains, considered safe by EFSA and commonly used as probiotics. The physiological tests carried out on our strains corroborated the genomic results. Moreover, the following functional traits of interest to application in the food sector were identified: the majority of tested strains displayed high acidification rate, high reducing ability, production of exopolysaccharides (EPS), arabinoxylan degradation ability, growth in the presence of fructo-oligosaccharides (FOS), bile and gastric juice tolerance, and antifungal activity. These results provide evidence for the possible use of selected strains of W. cibaria and W. confusa in the food sector. This polyphasic study adds to the body of knowledge on the functional and applicable characteristics of these controversial species of LAB. This knowledge contributes to design new selected cultures included in the QPS list required for food applications.

Potential Evaluation and Health Fostering Intrinsic Traits of Novel Probiotic Strain Enterococcus durans F3 Isolated from the Gut of Fresh Water Fish Catla catla.

Over the last few years, marine environment was found to be a source of surplus natural products and microorganisms with new bioactive secondary metabolites of interest which can divulge nutritional and biological impact on the host. This study aims to assess the possible, inherent and functional probiotic properties of a novel probiotic strain Enterococcus durans F3 (E. durans F3) isolated from the gut of fresh water fish Catla catla. Parameters for evaluating and describing the probiotics described in FAD/WHO guidelines were followed. E. durans F3 demonstrated affirmative results including simulated bile, acid and gastric juice tolerance with exhibited significant bactericidal effect against pathogens Staphylococcus aureus, Salmonella Typhi, Escherichia coli and Pseudomonas aeruginosa. This can be due to the enterocin produced by E. durans F3 strain, which was resolute by sodium dodecyl sulphate polyacrylamide gel electrophoresis (SDS-PAGE) gel with amplification of the anticipated fragment of a structural gene; enterocin A, followed by antibiotic susceptibility assessment. Effective antioxidant potentiality against α-diphenyl-α-picrylhydrazyl free radicals including lipase, bile salt hydrolase activity with auto-aggregation and cell surface hydrophobicity was similarly observed. Results are proving the potentiality of E. durans F3, which can also be used as probiotic starter culture in dairy industries for manufacturing new products that imparts health benefits to the host. Finding the potent and novel probiotic strains will also satisfy the current developing market demand for probiotics.

Probiotic properties and immunomodulatory activity of gastrointestinal tract commensal bacterial strains isolated from the edible farmed snail Cornu aspersum maxima

The aim of this study was to determine the in vitro probiotic properties as well as the immunomodulatory activity of bacterial strains isolated from the gastrointestinal tract of the edible-farmed land snail Cornu aspersum maxima. Forty lactic acid bacterial strains (named Sgs1-40) were isolated from the intestinal tract and eight strains (named SgmA-H) from the oesophagus-crop of snails. Several criteria were used to examine whether they may be applied as snail-specific for the screening of the presumptive probiotic bacterial strains. Principal Component Analysis using criteria such as the tolerance of these strains to the pedal mucus, gastric mucus, gastric juices and low pH, as well as the expression of the cell surface traits of hydrophobicity, biofilm formation and autoaggregation capacity revealed discrimination of twelve strains exhibiting presumptive in vitro probiotic properties. Injection of eight of these strains, which were identified as Lactobacillus plantarum, in snail haemocoel increased the recruitment and phagocytic activity of amoebocytes in snail haemolymph. The Sgs14 and SgmB strains, exhibiting the highest immunostimulatory activity in haemolymph, were FITC-labelled and orally administrated to snails for ten days. The Sgs14 strain was able to adhere to intestinal mucosa of snails and stimulate the chemotactic and phagocytic activity of amoebocytes in haemolymph as well as the bactericidal activity of haemolymph serum. These responses are potentially mediated by the regulation of TLRs expression in the gut mucosa. These data indicate that the determination of properties such as snail mucus and gastric juice tolerance, cell surface traits for adhesion as well as increased chemotactic and phagocytic activity in snail haemolymph are eligible criteria to screen for snail-specific probiotics. To the best of our knowledge, this is the first work that investigates the probiotic properties of gastrointestinal microflora of the terrestrial farmed snail Cornu aspersum maxima.

Probiotic properties of Bifidobacterium species isolated from mother’s milk and infant feces

Probiotics are live microorganisms that provide health benefits when consumed. Bifidobacteria are one of the major genera of bacteria that make up the colon flora in mammals and have great beneficial impact on health. This study was performed to culture and characterize some potential Bifidobacterium sp. isolated from mother's milk and infant feces. Eleven isolates were presumptively identified as Bifidobacteriums sp. based on morphological characteristic and biochemical properties such as catalase, oxidase, Esculin test, Gelatinase activities and production of gas from glucose. Probiotic potentials of the isolates were investigated through probiotic potentiality tests e.g. pH tolerance test, NaCl tolerance test, bile salt tolerance test, antimicrobial activity, growth rate in gastric juice, antimicrobial susceptibility (Antibiogram). Four of the isolates BI-3, BI-5, BI-9, and BI-14 were observed as potential probiotic based on their probiotic activities. These isolates showed resistance to stomach pH (pH 3.0), tolerance against 0.3% bile concentration and gastric juice tolerance. Most of the isolates were able to grow at 1- 6% NaCl concentration and the growth declined with the increase of the salt concentration. Proteolytic activity was measured to estimate the probable role of probiotics in protein digestion. For this purpose milk protein digestion was tested and these isolates had showed better proteolytic activity than others. Antimicrobial activity against pathogens showed better probiotic properties. These isolates were found to have moderately antibiotic susceptible to common antibiotics. This experiment revealed that these four isolates BI-3, BI-5, BI-9, and BI-14 have good probiotic properties and can be used as probiotics after successful molecular identification and completion of animal trial.
 Asian Australas. J. Biosci. Biotechnol. 2018, 3 (2), 122-135