Alterations in Gut Microbiota Correlate With Hematological Injuries Induced by Radiation in Beagles

Dynamics of gut microbiota and their associations with the corresponding hematological injuries postradiation remain to be elucidated. Using single whole-body exposure to 60Co-γ ray radiation at the sublethal dose of 2.5 Gy, we developed a beagle model of acute radiation syndrome (ARS) and then monitored the longitudinal changes of gut microbiome and hematology for 45 days. We found that the absolute counts of circulating lymphocytes, neutrophils, and platelets were sharply declined postradiation, accompanied by a largely shifted composition of gut microbiome that manifested as a significantly increased ratio of Firmicutes to Bacteroidetes. In irradiated beagles, alterations in hematological parameters reached a nadir on day 14, sustaining for 1 week, which were gradually returned to the normal levels thereafter. However, no structural recovery of gut microbiota was observed throughout the study. Fecal metagenomics revealed that irradiation increased the relative abundances of genus Streptococcus, species Lactobacillus animalis and Lactobacillus murinus, but decreased those of genera Prevotella and Bacteroides. Metagenomic functions prediction demonstrated that 26 altered KEGG pathways were significantly enriched on Day 14 and 35 postradiation. Furthermore, a total of 43 bacterial species were found to correlate well with hematological parameters by Spearman's analysis. Our results provide an insight into the longitudinal changes in intestinal microbiota at different clinical stages during ARS in canine. Several key microbes those tightly associated with the hematological alterations may serve as biomarkers to discriminate the different phases of host with ARS.

Isolation, characterization, and assessment of Bacillus rugosus potential as a new probiotic for aquaculture applications

Aquaculture is an important component of the world food supply and a significant source of protein. However, this industry faces numerous problems. Including poor fish feed digestion and uneconomic nutrient utilization. This can result in unsatisfactory growth rates and poor stock performance. Utilizing probiotics, which are beneficial microbes that can enhance digestive systems and general fish health, is one possible way to address these issues. This study was designed to identify and evaluate a novel strain of Bacillus as a promising probiotic. The strain of Bacillus rugosus that was examined and coded NM007 showed promising probiotic characteristics that could help fish digest and utilize their feed more efficiently, reduce feed waste, and improve their digestive systems. B. rugosus NM007 exhibited the ability to produce digestive enzymes like protease, amylase, and lipase, which are the main digestive enzymes. It showed strong auto-aggregation activity and co-aggregation activity with Aeromonas sp. and Streptococcus sp. It also demonstrated tolerance to the presence of bile salt, acidic pH, and salinity up to 60 ppt. The sensitivity analysis towards antibiotics, hemolytic activity and the safety assessment on Nile tilapia fish (Oreochromis niloticus) confirmed the safety of this isolate. Based on the findings of this investigation and the isolate's characterization, Bacillus rugosus NM007 could serve as a new promising probiotic bacterium for aquaculture.

Nutritional attributes and microbial metagenomic profile during solid-state fermentation of soybean meal inoculated with Lactobacillus acidophilus under non-sterile conditions

BACKGROUND

Soybean meal (SBM) is used widely in animal feed but it contains anti-nutritional factors (ANFs) such as protease inhibitors - immunogenic proteins that limit its utilization. Fermentative processes could help to reduce these ANFs. The aim of this study was to evaluate the nutritional attributes, bacterial community dynamics, and microbial metagenomic profile during the solid-state fermentation of SBM using a strain of the bacterium Lactobacillus acidophilus with or without pre-autoclaving treatment.

RESULTS

Following fermentation, there was a reduction in the pH and a concurrent increase in the population of lactic acid bacteria. Fermentation also resulted in an increase in both crude and soluble protein levels. Trypsin inhibitor levels decreased after fermentation, particularly in fermented SBM that had not been pre-autoclaved, with an inactivation rate higher than 90%. Moreover, high-molecular-weight peptides (44-158 kDa), specifically some polypeptides from the soybean immunogen glycinin and β-conglycinin, underwent degradation during the fermentation process. Bacterial community analysis revealed the dominance of the Lactobacillus genus in all samples, regardless of the treatments applied. Metagenomic profiling identified L. acidophilus as the dominant species in inoculated SBM, irrespective of whether pre-autoclaving was conducted or not.

CONCLUSION

This study demonstrates the feasibility of solid-state fermentation with L. acidophilus under non-sterile conditions to inactivate trypsin inhibitor and increase protein concentration and hydrolysate immunogen proteins into low-molecular-weight peptides in SBM. Lactobacillus acidophilus inoculum also inhibited the growth of undesirable bacteria. This knowledge contributes to our understanding of the potential applications of solid-state fermentation with L. acidophilus in improving the nutritional quality of SBM. © 2024 Society of Chemical Industry.

Nutrient consumption patterns of Lactobacillus acidophilus

BACKGROUND

One of the greatest challenges in using Lactobacillus acidophilus as a probiotic is acid stress. The current research aimed to identify substances that help L. acidophilus resist acid stress; this was achieved through assessing its nutrient consumption patterns under various pH conditions.

RESULTS

The consumption rates of alanine, uracil, adenine, guanine, niacin, and manganese were consistently higher than 60% for L. acidophilus LA-5 cultured at pH 5.8, 4.9, and 4.4. The consumption rates of glutamic acid + glutamine and thiamine increased with decreasing pH and were higher than 60% at pH 4.9 and 4.4. The viable counts of L. acidophilus LA-5 were significantly increased under the corresponding acidic stress conditions (pH 4.9 and 4.4) through the appropriate addition of either alanine (3.37 and 2.81 mmol L-1), glutamic acid + glutamine (4.77 mmol L-1), guanine (0.13 and 0.17 mmol L-1), niacin (0.02 mmol L-1), thiamine (0.009 mmol L-1), or manganese (0.73 and 0.64 mmol L-1) (P < 0.05). The viable counts of L. acidophilus LA-5 cultured in a medium supplemented with combined nutritional factors was 1.02-1.03-fold of the counts observed in control medium under all acid conditions (P < 0.05).

CONCLUSION

Alanine, glutamic acid + glutamine, guanine, niacin, thiamine, and manganese can improve the growth of L. acidophilus LA-5 in an acidic environment in the present study. The results will contribute to optimizing strategies to enhance the acid resistance of L. acidophilus and expand its application in the fermentation industry. © 2024 Society of Chemical Industry.

Efficacy of probiotic supplements in improving the symptoms of psychosis, anxiety, insomnia, and anorexia due to amphetamine and methamphetamine use: a randomized clinical trial

RATIONALE

Changes in the density and diversity of gut microbiota in chronic use of methamphetamine have been mentioned as contributors to psychotic and anxiety symptoms, sleep problems, and loss of appetite.

OBJECTIVE

In this placebo-controlled clinical trial, we investigated the effect of the probiotic Lactobacillus Acidophilus in improving psychiatric symptoms among hospitalized patients with chronic methamphetamine use along with psychotic symptoms.

METHODS

60 inpatients with a history of more than 3 years of methamphetamine use, were randomly assigned to one of two groups receiving either a probiotic capsule or placebo along with risperidone for 8 weeks based on a simple randomization method. In weeks 0, 4, and 8, patients were evaluated using the Brief Psychiatric Rating Scale (BPRS), Beck Anxiety Inventory (BAI), Pittsburgh Sleep Quality Index (PSQI), Simple Appetite Nutritional Questionnaire (SANQ), and Body Mass Index (BMI).

RESULTS

Compared to the control group, patients receiving probiotics had better sleep quality, greater appetite, and higher body mass index (there were significant interaction effects of group and time at Week 8 in these variables (t = -3.32, B = -1.83, p = .001, d = 0.89), (t = 10.50, B = 2.65, p <.001, d = 1.25) and (t = 3.40, B = 0.76, p <.001, d = 0.30), respectively. In terms of the improvement of psychotic and anxiety symptoms, there was no statistically significant difference between the two groups.

CONCLUSIONS

The use of probiotics was associated with improved sleep quality, increased appetite, and increased body mass index in patients with chronic methamphetamine use. Conducting more definitive clinical trials with larger sample sizes and longer-term follow-up of cases is recommended.

Mechanisms of medicinal, pharmaceutical, and immunomodulatory action of probiotics bacteria and their secondary metabolites against disease management: an overview

Probiotics or bacteriotherapy is today's hot issue for public entities (Food and Agriculture Organization, and World Health Organization) as well as health and food industries since Metchnikoff and his colleagues hypothesized the correlation between probiotic consumption and human's health. They contribute to the newest and highly efficient arena of promising biotherapeutics. These are usually attractive in biomedical applications such as gut-related diseases like irritable bowel disease, diarrhea, gastrointestinal disorders, fungal infections, various allergies, parasitic and bacterial infections, viral diseases, and intestinal inflammation, and are also worth immunomodulation. The useful impact of probiotics is not limited to gut-related diseases alone. Still, these have proven benefits in various acute and chronic infectious diseases, like cancer, human immunodeficiency virus (HIV) diseases, and high serum cholesterol. Recently, different researchers have paid special attention to investigating biomedical applications of probiotics, but consolidated data regarding bacteriotherapy with a detailed mechanistically applied approach is scarce and controversial. The present article reviews the bio-interface of probiotic strains, mainly (i) why the demand for probiotics?, (ii) the current status of probiotics, (iii) an alternative to antibiotics, (iv) the potential applications towards disease management, (v) probiotics and industrialization, and (vi) futuristic approach.

Oral Administration of Lactobacillus acidophilus LA5 Prevents Alveolar Bone Loss and Alters Oral and Gut Microbiomes in a Murine Periodontitis Experimental Model

Periodontitis is a destructive inflammatory response triggered by dysbiosis. Lactobacillus acidophilus LA5 (LA5) may impair microbial colonization and alter the host. Thus, we evaluated the effect of LA5 on alveolar bone loss in a periodontitis murine model and investigated its effect on the oral and gut microbiomes. Porphyromonas gingivalis, Prevotella intermedia, Fusobacterium nucleatum, and Streptococcus gordonii were inoculated in C57BL/6 mice (P+), with LA5 (L+). SHAM infected controls (P- and/or L- groups) were also evaluated. After 45 days, alveolar bone loss in the maxilla and oral and gut microbiomes were determined. The administration of LA5 controlled the microbial consortium-induced alveolar bone loss. Periodontopathogens infection resulted in shifts in the oral and gut microbiomes consistent with dysbiosis, and LA5 reshaped these changes. The oral microbiome of P+L- group showed the increased abundance of Enterococaccea, Streptoccocaceae, Staphylococcaceae, Moraxellaceae, and Pseudomonadaceae, which were attenuated by the administration of LA5 to the infected group (P+L+). The administration of LA5 to otherwise non-infected mice resulted in the increased abundance of the superphylum Patescibacteria and the family Saccharamonadaceae in the gut. These data indicate L. acidophilus LA5 as a candidate probiotic for the control of periodontitis.

Novel Synergistic Probiotic Intervention: Transcriptomic and Metabolomic Analysis Reveals Ameliorative Effects on Immunity, Gut Barrier, and Metabolism of Mice during Salmonella typhimurium Infection

Salmonella typhimurium (S. typhimurium), a prevalent cause of foodborne infection, induces significant changes in the host transcriptome and metabolome. The lack of therapeutics with minimal or no side effects prompts the scientific community to explore alternative therapies. This study investigates the therapeutic potential of a probiotic mixture comprising Lactobacillus acidophilus (L. acidophilus 1.3251) and Lactobacillus plantarum (L. plantarum 9513) against S. typhimurium, utilizing transcriptome and metabolomic analyses, a novel approach that has not been previously documented. Twenty-four SPF-BALB/c mice were divided into four groups: control negative group (CNG); positive control group (CPG); probiotic-supplemented non-challenged group (LAPG); and probiotic-supplemented Salmonella-challenged group (LAPST). An RNA-sequencing analysis of small intestinal (ileum) tissue revealed 2907 upregulated and 394 downregulated DEGs in the LAPST vs. CPG group. A functional analysis of DEGs highlighted their significantly altered gene ontology (GO) terms related to metabolism, gut integrity, cellular development, and immunity (p ≤ 0.05). The KEGG analysis showed that differentially expressed genes (DEGs) in the LAPST group were primarily involved in pathways related to gut integrity, immunity, and metabolism, such as MAPK, PI3K-Akt, AMPK, the tryptophan metabolism, the glycine, serine, and threonine metabolism, ECM-receptor interaction, and others. Additionally, the fecal metabolic analysis identified 1215 upregulated and 305 downregulated metabolites in the LAPST vs. CPG group, implying their involvement in KEGG pathways including bile secretion, propanoate metabolism, arginine and proline metabolism, amino acid biosynthesis, and protein digestion and absorption, which are vital for maintaining barrier integrity, immunity, and metabolism. In conclusion, these findings suggest that the administration of a probiotic mixture improves immunity, maintains gut homeostasis and barrier integrity, and enhances metabolism in Salmonella infection.

A longitudinal field study of commercial honey bees shows that non-native probiotics do not rescue antibiotic treatment, and are generally not beneficial

Probiotics are widely used in agriculture including commercial beekeeping, but there is little evidence supporting their effectiveness. Antibiotic treatments can greatly distort the gut microbiome, reducing its protective abilities and facilitating the growth of antibiotic resistant pathogens. Commercial beekeepers regularly apply antibiotics to combat bacterial infections, often followed by an application of non-native probiotics advertised to ease the impact of antibiotic-induced gut dysbiosis. We tested whether probiotics affect the gut microbiome or disease prevalence, or rescue the negative effects of antibiotic induced gut dysbiosis. We found no difference in the gut microbiome or disease markers by probiotic application or antibiotic recovery associated with probiotic treatment. A colony-level application of the antibiotics oxytetracycline and tylosin produced an immediate decrease in gut microbiome size, and over the longer-term, very different and persistent dysbiotic effects on the composition and membership of the hindgut microbiome. Our results demonstrate the lack of probiotic effect or antibiotic rescue, detail the duration and character of dysbiotic states resulting from different antibiotics, and highlight the importance of the gut microbiome for honeybee health.

Safety Assessment and Probiotic Potential Comparison of Bifidobacterium longum subsp. infantis BLI-02, Lactobacillus plantarum LPL28, Lactobacillus acidophilus TYCA06, and Lactobacillus paracasei ET-66

Bifidobacterium longum subsp. infantis BLI-02, Lactobacillus paracasei ET-66, Lactobacillus plantarum LPL28, and Lactobacillus acidophilus TYCA06, isolated from healthy breast milk, miso, and the healthy human gut, were assessed for safety in this study. BLI-02, LPL28, TYCA06, and ET-66 exhibited no antibiotic resistance and mutagenic activity in the Ames test at the highest dosage (5000 μg/plate). No genotoxicity was observed in micronucleus and chromosomal aberration assays in rodent spermatogonia at the maximum dosage of 10 g/kg body weight (BW). No acute and sub-chronic toxicity occurred in mice and rats at the maximum tested dosage of 10 g/kg BW and 1.5 g/kg BW, respectively. The lyophilized powder of these strains survived a low pH and high bile salt environment, adhering strongly to Caco-2 cells. Unique antimicrobial activities were noted in these strains, with BLI-02 demonstrating the best growth inhibition against Vibrio parahaemolyticus, LPL28 exhibiting the best growth inhibition against Helicobacter pylori, and ET-66 showing the best growth inhibition against Aggregatibacter actinomycetemcomitans. Based on the present study, the lyophilized powder of these four strains appears to be a safe probiotic supplement at tested dosages. It should be applicable for clinical or healthcare applications.

In silico prospection of Lactobacillus acidophilus strains with potential probiotic activity

Lactic acid bacteria (LAB) are fermentative microorganisms and perform different roles in biotechnological processes, mainly in the food and pharmaceutical industries. Among the LAB, Lactobacillus acidophilus is a species that deserves to be highlighted for being used both in prophylaxis and in the treatment of pathologies. Most of the metabolites produced by this species are linked to the inhibition of pathogens. In this study, we utilized a pangenomic and metabolic annotation analysis using Roary and BlastKOALA, ML-based probiotic activity prediction with iProbiotic and whole-genome similarity using ANI to identify strains of L. acidophilus with potential probiotic activity. According to the results in BlastKOALA and iProbiotics, L. acidophilus NCTC 13721 had the greatest potential among the 64 strains tested, both in terms of its ability to be a Lactobacillus spp. probiotic, when in the amount of genes involved in the metabolism of organic acids and quorum sensing. In addition, DSM 20079 proved to be promising for prospecting new probiotic Lactobacillus from BlastKOALA analyses, as they presented similar results in the number of genes involved in the production of lactic acid, acetic acid, hydrogen peroxide, except for quorum sensing where the NCTC 13721 strain had 14 more genes. L. acidophilus NCTC 13721 and L. acidophilus La-5 strains showed greater ability to be Lactobacillus spp. probiotic capacity, showing 84.8% and 51.9% capacity in the iProbiotics tool, respectively. When analyzed in ANI, none of the evaluated strains showed genomic similarity with NCTC 13721. In contrast, the DSM 20079 strain showed genomic similarity with all evaluated strains except NCTC 13721. Furthermore, eight strains with characteristics with approximately 100% genomic similarity to La-5 were listed: S20_1, LA-5, FSI4, APC2845, LA-G80-111, DS1_1A, LA1, and BCRC 14065. Therefore, according to the findings in iProbiotics and BlastKoala, among the 64 strains evaluated, NCTC 13721 is the most promising strain to be used for future in vitro studies.

Effects and Mechanisms of Resveratrol on the Adhesion of Lactobacillus acidophilus NCFM

Based on the adhesion and surface properties of Lactobacillus acidophilus NCFM, five common polyphenols in fruits and vegetables, including resveratrol, epicatechin, quercetin, hesperidin, and caffeic acid, were screened, and the reasons for resveratrol promoting adhesion were systematically explained. The results showed that resveratrol could significantly enhance NCFM adhesion to mucin (1.73 fold), followed by epicatechin (1.47 fold), caffeic acid (1.30 fold), and hesperidin (0.99 fold), while quercetin had a certain degree of inhibition (0.84 fold). The effects of these polyphenols on surface hydrophobicity and auto-aggregation of NCFM were consistent with adhesion results. Then, how resveratrol promotes NCFM adhesion was further explored. The results of the proteomic analysis showed that resveratrol changed the surface layer proteins of NCFM, involving 4 up-regulated proteins and 12 down-regulated proteins. In addition, resveratrol promoted the expression of mucin genes and the glycosylation of mucins on the HT-29 cell surface. Our results indicate that resveratrol changes the surface layer proteins of NCFM to modify surface properties and adhere to mucins. Meanwhile, resveratrol promotes expression and glycosylation of mucins in HT-29 cells. Our findings provide theoretical support for an in-depth explanation of the interaction among resveratrol, NCFM, and the HT-29 cells.

Perspectives in Searching Antimicrobial Peptides (AMPs) Produced by the Microbiota

Changes in the structure and function of the microbiota are associated with various human diseases. These microbial changes can be mediated by antimicrobial peptides (AMPs), small peptides produced by the host and their microbiota, which play a crucial role in host-bacteria co-evolution. Thus, by studying AMPs produced by the microbiota (microbial AMPs), we can better understand the interactions between host and bacteria in microbiome homeostasis. Additionally, microbial AMPs are a new source of compounds against pathogenic and multi-resistant bacteria. Further, the growing accessibility to metagenomic and metatranscriptomic datasets presents an opportunity to discover new microbial AMPs. This review examines the structural properties of microbiota-derived AMPs, their molecular action mechanisms, genomic organization, and strategies for their identification in any microbiome data as well as experimental testing. Overall, we provided a comprehensive overview of this important topic from the microbial perspective.

Aroma-based discrimination of Egyptian versus Indian guava fruits and in response to probiotics as analyzed via SPME/GC-MS and chemometric tools

Guava tree (Psidium guajava L., Myrtaceae) is an economic grown worldwide, particularly in tropical and subtropical regions. Guavas encompass numerous cultivars (cvs.) that were discriminated in previous studies based on leaf morphological features and profile of volatile organic compounds (VOCs). Nevertheless, fruit VOCs have also shown outstanding potential for discrimination of other plant taxa, which has not been utilized in guava. Hence, the current study investigates the various guava cvs. harvested from India and Egypt. A total of 5 samples were analyzed by solid phase microextraction coupled to gas chromatography/mass spectrometry. Results led to the detection of 42 VOCs belonging to aldehydes, alcohols, esters, ketones, aliphatic and aromatic hydrocarbons, in addition to monoterpene and sesquiterpene hydrocarbons. Butylated hydroxytoluene and β-caryophyllene were predominant reaching 77% and 41% in Egyptian and Indian guava, respectively. The impact of probiotic fermentation, i.e., Lactobacillus acidophilus and L. plantarum on aroma profile was not significantly different (p > 0.05). Multivariate data analyses were further applied for samples classification and markers determination, including principal component analysis (PCA) and orthogonal partial least squares discriminant analysis (OPLS-DA). PCA score plot showed clear segregation of Egyptian from Indian specimens, whereas OPLS-DA revealed that β-caryophyllene was associated with white fruit versus 3-butenyl isothiocyanate and muurolol in red fruit type in the case of Indian guava. The richness of Egyptian guava in butylated hydroxytoluene in addition to the presence of vitamin C may potentiate its antioxidant activity, to be followed in subsequent studies regarding its health effects.

In Vitro Evaluation of Intestinal Transport and High-Density Fermentation of Lactobacillus acidophilus

Lactobacillus acidophilus strains have limiting factors such as low cell density and complex nutritional requirements in industrial production, which greatly restricts their industrial application. In this study, fermentation conditions for L. acidophilus were optimized and transcriptomic analysis used to understand growth mechanisms under high-density fermentation conditions. We found that L. acidophilus IMAU81186 has strong tolerance to gastrointestinal juice. In addition, its optimal culture conditions were 3% inoculum (v/v); culture temperature 37 °C; initial pH 6.5; and medium composition of 30.18 g/L glucose, 37.35 g/L soybean peptone, 18.68 g/L fish peptone, 2.46 g/L sodium citrate, 6.125 g/L sodium acetate, 2.46 g/L K2HPO4, 0.4 g/L MgSO4·7H2O,0.04 g/L MnSO4·5H2O, 0.01 g/L serine, and 0.3 g/L uracil. After optimization, viable counts of IMAU81186 increased by 7.03 times. Differentially expressed genes in IMAU81186 were analyzed at different growth stages using transcriptomics. We found that a single carbon source had limitations in improving the biomass of the strain, and terP and bfrA were significantly down-regulated in the logarithmic growth period, which may be due to the lack of extracellular sucrose. After optimizing the carbon source, we found that adding 12 g/L sucrose to the culture medium significantly increased cell density.

Limosilactobacillus reuteri in immunomodulation: molecular mechanisms and potential applications

Frequent use of hormones and drugs may be associated with side-effects. Recent studies have shown that probiotics have effects on the prevention and treatment of immune-related diseases. Limosilactobacillus reuteri (L. reuteri) had regulatory effects on intestinal microbiota, host epithelial cells, immune cells, cytokines, antibodies (Ab), toll-like receptors (TLRs), tryptophan (Try) metabolism, antioxidant enzymes, and expression of related genes, and exhibits antibacterial and anti-inflammatory effects, leading to alleviation of disease symptoms. Although the specific composition of the cell-free supernatant (CFS) of L. reuteri has not been clarified, its efficacy in animal models has drawn increased attention to its potential use. This review summarizes the effects of L. reuteri on intestinal flora and immune regulation, and discusses the feasibility of its application in atopic dermatitis (AD), asthma, necrotizing enterocolitis (NEC), systemic lupus erythematosus (SLE), rheumatoid arthritis (RA), and multiple sclerosis (MS), and provides insights for the prevention and treatment of immune-related diseases.

Mining the genome of Bacillus velezensis FS26 for probiotic markers and secondary metabolites with antimicrobial properties against aquaculture pathogens

Bacillus velezensis FS26 is a bacterium from the genus Bacillus that has been proven as a potential probiotic in aquaculture with a good antagonistic effect on Aeromonas spp. and Vibrio spp. Whole-genome sequencing (WGS) allows a comprehensive and in-depth analysis at the molecular level, and it is becoming an increasingly significant technique in aquaculture research. Although numerous probiotic genomes have been sequenced and investigated recently, there are minimal data on in silico analysis of B. velezensis as a probiotic bacterium isolated from aquaculture sources. Thus, this study aims to analyse the general genome characteristics and probiotic markers from the B. velezensis FS26 genome with secondary metabolites predicted against aquaculture pathogens. The B. velezensis FS26 genome (GenBank Accession: JAOPEO000000000) assembly proved to be of high quality, with eight contigs containing 3,926,371 bp and an average G + C content of 46.5%. According to antiSMASH analysis, five clusters of secondary metabolites from the B. velezensis FS26 genome showed 100% similarity. These clusters include Cluster 2 (bacilysin), Cluster 6 (bacillibactin), Cluster 7 (fengycin), Cluster 8 (bacillaene), and Cluster 9 (macrolactin H), which signify promising antibacterial, antifungal, and anticyanobacterial agents against pathogens in aquaculture. The probiotic markers of B. velezensis FS26 genome for adhesion capability in the hosts' intestine, as well as the acid and bile salt-tolerant genes, were also detected through the Prokaryotic Genome Annotation System (Prokka) annotation pipeline. These results are in agreement with our previous in vitro data, suggesting that the in silico investigation facilitates establishing B. velezensis FS26 as a beneficial probiotic for use in aquaculture.

Sustainable Ornamental Fish Aquaculture: The Implication of Microbial Feed Additives

Ornamental fish trade represents an important economic sector with an export turnover that reached approximately 5 billion US dollars in 2018. Despite its high economic importance, this sector does not receive much attention. Ornamental fish husbandry still faces many challenges and losses caused by transport stress and handling and outbreak of diseases are still to be improved. This review will provide insights on ornamental fish diseases along with the measures used to avoid or limit their onset. Moreover, this review will discuss the role of different natural and sustainable microbial feed additives, particularly probiotics, prebiotics, and synbiotics on the health, reduction in transport stress, growth, and reproduction of farmed ornamental fish. Most importantly, this review aims to fill the informational gaps existing in advanced and sustainable practices in the ornamental fish production.

Combination of Lactobacillus plantarum HAC03 and Garcinia cambogia Has a Significant Anti-Obesity Effect in Diet-Induced Obesity Mice

Obesity is a major global health problem which is associated with various diseases and psychological conditions. Increasing understanding of the relationship between obesity and gut microbiota has led to a worldwide effort to use microbiota as a treatment for obesity. However, several clinical trials have shown that obesity treatment with single strains of probiotics did not achieve as significant results as in animal studies. To overcome this limitation, we attempted to find a new combination that goes beyond the effects of probiotics alone by combining probiotics and a natural substance that has a stronger anti-obesity effect. In this study, we used a diet-induced obesity mouse (DIO) model to investigate the effects of combining Lactobacillus plantarum HAC03 with Garcinia cambogia extract, as compared to the effects of each substance alone. Combining L. plantarum HAC03 and G. cambogia, treatment showed a more than two-fold reduction in weight gain compared to each substance administered alone. Even though the total amount administered was kept the same as for other single experiments, the combination treatment significantly reduced biochemical markers of obesity and adipocyte size, in comparison to the treatment with either substance alone. The treatment with a combination of two substances also significantly decreased the gene expression of fatty acid synthesis (FAS, ACC, PPARγ and SREBP1c) in mesenteric adipose tissue (MAT). Furthermore, 16S rRNA gene sequencing of the fecal microbiota suggested that the combination of L. plantarum HAC03 and G. cambogia extract treatment changed the diversity of gut microbiota and altered specific bacterial taxa at the genus level (the Eubacterium coprostanoligenes group and Lachnospiraceae UCG group) and specific functions (NAD salvage pathway I and starch degradation V). Our results support that the idea that the combination of L. plantarum HAC03 and G. cambogia extract has a synergistic anti-obesity effect by restoring the composition of the gut microbiota. This combination also increases the abundance of bacteria responsible for energy metabolism, as well as the production of SCFAs and BCAAs. Furthermore, no significant adverse effects were observed during the experiment.

In Vitro Characterization of Probiotic Potential of Limosilactobacillus fermentum against Salmonella Gallinarum Causing Fowl Typhoid

Fowl typhoid, a septicaemic disease of poultry, is caused by Salmonella Gallinarum and leads to severe economic losses. The aim of the present study was to isolate, select and characterize indigenous probiotic lactobacilli with anti-Salmonella Gallinarum activity. A total 55 lactobacilli were isolated from the caeca and ileum parts of healthy chickens and identified to species level by 16S rDNA sequencing. All the isolates were initially screened for antimicrobial activity and selected isolates were further subjected to in vitro evaluation of probiotic properties. Lactobacilli isolates (n = 21) showed varying levels of activity (08-18 mm) against Salmonella Gallinarum. These selected isolates also showed tolerance to acidic conditions (pH 3 and 4). Out of these 21 isolates, 13 showed growth (>0.5 OD at 600 nm) 0.3% bile salts. Moreover, these isolates also had the ability of auto-aggregation (20.05 ± 0.62%-50.70 ± 1.40%), and co-aggregation with Salmonella Gallinarum (5.22 ± 0.21%-42.07 ± 0.70%). Results revealed that lactobacilli had a higher level of resistance to vancomycin (100%), streptomycin (100%), ciprofloxacin (95%), gentamicin (90%), doxycycline (90%), oxytetracycline (85%), and bacitracin (80%), and a lower level of resistance to penicillin (33%), erythromycin (28%), chloramphenicol (23%), fusidic acid (23%) and amoxicillin (4%). The Limosilactobacillus fermentum PC-10 and PC-76 were sensitive to most of the antibiotics. The overall results revealed that two Limosilactobacillus fermentum strains (PC-10 and PC-76) fulfill the in vitro selection criteria of probiotics, i.e, tolerance to low pH, resistance to bile salts, auto-aggregation, co-aggregation with Salmonella Gallinarum, and absence of acquired antibiotic resistance. The Limosilactobacillus fermentum PC-10 and PC-76 also inhibited the (>5 log10) growth of Salmonella Gallinarum in co-culture assay. It is concluded that Limosilactobacillus fermentum PC-10 and PC-76 may be further investigated and developed as anti-Salmonella Gallinarum probiotics for poultry.

Associations between dairy intake and mortality due to all-cause and cardiovascular disease: the Japan Public Health Center-based prospective study

BACKGROUND

Some studies have investigated the relation between dairy products and mortality, but with inconsistent results.

OBJECTIVE

We examined the association between the consumption of dairy products and the risk of all-cause, cancer-related, and cardiovascular disease (CVD)-related mortality.

METHODS

From the Japan Public Health Center-based Prospective (JPHC) study, 43,117 males and 50,193 females with no history of cancer or CVD finished the food frequency questionnaire (FFQ) and were included in the study. Intake of dairy products was assessed using the FFQ and adjusted for total energy by using the residual method. We used multivariate Cox proportional hazard models to calculate hazard ratios (HRs) and 95% confidence intervals (95% CIs) for mortality risk in males and females.

RESULTS

14,211 deaths in males and 9547 deaths in females from all causes were identified during an average follow-up of 19.3 years. For males, total dairy consumption was nonlinearly and significantly associated with lower risk of mortality from all causes [the third quartile, HR = 0.87 (0.83, 0.91), the fourth quartile, HR = 0.89 (0.85, 0.94), P for nonlinearity < 0.001] and CVD [the third quartile, HR = 0.77 (0.70, 0.85), the fourth quartile, HR = 0.78 (0.70, 0.86), P for nonlinearity < 0.001]. Milk and fermented milk intake were inversely associated with all-cause and CVD-related mortality in males. Cheese consumption was inversely associated with CVD-related mortality among males. There was no association between total dairy intake and mortality risk among females.

CONCLUSION

For Japanese people, consumption of dairy products was associated with a decreased risk of mortality from all-cause and cardiovascular diseases among males.

Metagenomics Analysis of Breast Microbiome Highlights the Abundance of Rothia Genus in Tumor Tissues

Breast cancer is one of the main global priorities in terms of public health. It remains the most frequent cancer in women and is the leading cause of their death. The human microbiome plays various roles in maintaining health by ensuring a dynamic balance with the host or in the appearance of various pathologies including breast cancer. In this study, we performed an analysis of bacterial signature differences between tumor and adjacent tissues of breast cancer patients in Morocco. Using 16S rRNA gene sequencing, we observed that adjacent tissue contained a much higher percentage of the Gammaproteobacteria class (35.7%) while tumor tissue was characterized by a higher percentage of Bacilli and Actinobacteria classes, with about 18.8% and 17.2% average abundance, respectively. Analysis of tumor subtype revealed enrichment of genus Sphingomonodas in TNBC while Sphingomonodas was predominant in HER2. The LEfSe and the genus level heatmap analysis revealed a higher abundance of the Rothia genus in tumor tissues. The identified microbial communities can therefore serve as potential biomarkers for prognosis and diagnosis, while also helping to develop new strategies for the treatment of breast cancer patients.

Commensal Lactobacilli Metabolically Contribute to Cervical Epithelial Homeostasis in a Species-Specific Manner

In reproductive-age women, the vaginal microbiome is typically dominated by one or a few Lactobacillus species, including Lactobacillus crispatus, Lactobacillus iners, Lactobacillus paragasseri, Lactobacillus mulieris, and Lactobaccillus crispatus, has been associated with optimal cervicovaginal health; however, much is still unknown about how other lactobacilli metabolically contribute to cervicovaginal health. We hypothesized that metabolites of each Lactobacillus species differ and uniquely contribute to health and homeostasis. To address this hypothesis, we utilized a human three-dimensional (3D) cervical epithelial cell model in conjunction with genomics analyses and untargeted metabolomics to determine the metabolic contributions of less-studied vaginal lactobacilli-L. iners, L. paragasseri, and L. mulieris. Our study validated that vaginal lactobacilli exhibit a close phylogenetic relationship. Genomic findings from publicly available strains and those used in our study indicated that L. iners is metabolically distinct from other species of lactobacilli, likely due to a reduced genome size. Lactobacilli and mock controls were distinguishable based on global metabolic profiles. We identified 95 significantly altered metabolites (P < 0.05) between individual lactobacilli and mock controls. Metabolites related to amino acid metabolism were shared among the lactobacilli. N-Acetylated amino acids with potential antimicrobial properties were significantly elevated in a species-specific manner. L. paragasseri and L. iners shared aromatic, but not carbohydrate-derived, lactic acid metabolites with potential antimicrobial properties that may contribute to homeostasis of the cervicovaginal environment. Additionally, L. iners uniquely altered lipid metabolism, which may be a sign of adaptation to the cervicovaginal niche. Overall, these findings further elucidate the metabolic contributions of three key vaginal Lactobacillus species in gynecological health. IMPORTANCE Lactobacillus species contribute to cervicovaginal health by their production of lactic acid and other antimicrobial compounds. Yet, much is still unknown regarding the metabolic potential of lesser-studied but common vaginal lactobacilli. Here, we used untargeted metabolomics coupled with our 3D cervical epithelial cell model to identify metabolic differences among vaginal Lactobacillus species (Lactobacillus iners, Lactobacillus paragasseri, and Lactobacillus mulieris) and how those differences related to maintaining homeostasis of the cervical epithelium. Human 3D cell models are essential tools for studying host-bacteria interactions and reducing confounding factors inherent in clinical studies. Therefore, these unique models allowed us to decipher the putative lactobacilli mechanisms that contribute to their roles in health or disease. Metabolic analyses revealed distinct profiles of each Lactobacillus species but also shared metabolic contributions associated with antimicrobial activity: amino acid metabolism, N-acetylated amino acids, and aromatic lactic acids. These patterns provided validation of metabolites associated with health in clinical studies and provided novel targets, including immunomodulatory and antimicrobial metabolites, for postbiotic therapies.

Application of pre-adaptation strategies to improve the growth of probiotic lactobacilli under food-relevant stressful conditions

While formulating a probiotic food, it is mandatory to make sure that the viability of probiotics is adequate at the point of consumption, which can be strongly compromised by stressful conditions due to low pH and high osmolarity. In this study, three probiotic lactobacilli were subjected to different pre-adaptation conditions, and the turbidimetric growth kinetics in challenging conditions (pH 4.0-6.5, NaCl 1-7%, sucrose 0.1-0.7 M) were evaluated. Different effects were observed for Lactobacillus acidophilus, Lacticaseibacillus casei, and Lactiplantibacillus plantarum. Indeed, pre-exposition to sub-optimal conditions in terms of pH and % NaCl significantly improved the ability of L. acidophilus and L. casei to overcome the osmotic stress due to salt or sucrose, and similar effects were observed for acidic stress. L. plantarum showed to be more tolerant to the challenging conditions applied in this study. Anyway, the pre-adaptation at conditions SUB_1 (pH 4.5 and NaCl 4%) and SUB_2 (pH 5 and NaCl 2%) speeded-up its growth kinetics by reducing the length of the lag phase under sucrose stress and enhancing the maximum growth rate at the highest pH tested. Moreover, an improvement in biomass amount was observed under sucrose stress. The whole data evidenced that the application of the appropriate pre-adaptation condition could contribute to making probiotics more robust towards challenging conditions due to food matrix, processing, and storage as well as gastrointestinal transit. Further studies will be necessary to gain insight into the proteomics and metabolomics responsible for increased tolerance to stressful conditions.

Lactobacillus acidophilus regulates abnormal serotonin availability in experimental ulcerative colitis

OBJECTIVES

Probiotics are known to play a beneficial role in curing irritable bowel syndrome such as ulcerative colitis. Commensal Lactobacillus species are thought to play a protective role against ulcerative colitis, as they restore homeostasis in intestinal disorders. Abnormal serotonin availability has been described in ulcerative colitis, but the underlying mechanism is still unclear. The aim of this study was to determine the anti-inflammatory role of Lactobacillus acidophilus (L. acidophilus) and its effect on serotonin expression.

METHODS

Ulcerative colitis was created with the intrarectal administration of acetic acid. A total of 40 adult male rats were divided into five groups of eight rats as control, sham, experimental colitis, treatment (Colitis + L. acidophilus) and protective group (L. acidophilus + colitis). To evaluate the effects of L. acidophilus on serotonin expression in ulcerative colitis, this bacterial strain was administered orally to the rats with acetic acid-induced colitis. After oral administration of L. acidophilus for 14 days, serotonin content was biochemically measured and serotonin expression was evaluated immunohistochemically.

RESULTS

The expression of serotonin and its protein content was significantly increased in colitis compared to the control and sham groups. Abnormal serotonin availability in the rats with acetic acid-induced colitis was significantly reduced by the L. acidophilus.

CONCLUSIONS

In our study, it was observed that the amount of serotonin in the intestinal tissue increased excessively with ulcerative colitis. In addition, L.acidophilus has been found to reduce the abnormally increased amount of serotonin in the colon tissue, as well as reduce the inflammation in the intestinal tissue that occurs with ulcerative colitis. With our findings, it is predicted that probiotic application can be used as a treatment option in ulcerative colitis.

Lactobacillus for the treatment and prevention of atopic dermatitis: Clinical and experimental evidence

Atopic dermatitis (AD) is a chronic inflammatory skin disease, accompanied by itching and swelling. The main pathological mechanism of AD is related to the imbalance between Type 2 helper cells (Th2 cells) and Type 1 helper cells (Th1 cells). Currently, no safe and effective means to treat and prevent AD are available; moreover, some treatments have side effects. Probiotics, such as some strains of Lactobacillus, can address these concerns via various pathways: i) facilitating high patient compliance; ii) regulating Th1/Th2 balance, increasing IL-10 secretion, and reducing inflammatory cytokines; iii) accelerating the maturation of the immune system, maintaining intestinal homeostasis, and improving gut microbiota; and iv) improving the symptoms of AD. This review describes the treatment and prevention of AD using 13 species of Lactobacillus. AD is commonly observed in children. Therefore, the review includes a higher proportion of studies on AD in children and fewer in adolescents and adults. However, there are also some strains that do not improve the symptoms of AD and even worsen allergies in children. In addition, a subset of the genus Lactobacillus that can prevent and relieve AD has been identified in vitro. Therefore, future studies should include more in vivo studies and randomized controlled clinical trials. Given the advantages and disadvantages mentioned above, further research in this area is urgently required.

Isolation and characterization of potential Lactobacillus acidophilus strains isolated from pig feces

The aim of this study was to isolate and characterize Lactic Acid Bacteria (LAB) from 16 feces samples of pig farm, and to evaluate the probiotic potential of these isolates as potential oral probiotic candidates. The selection process was based on the isolation, identification, and a series of experiments for the selection of appropriate candidates with beneficial properties. The results demonstrated that most of LAB showed relatively strong resistance to pH 2.5 and high bile salts (1%), and had good survival in simulated gastric and intestinal juice. 9 isolates displayed antimicrobial activities against Bacillus cereus, Staphylococcus aureus, Listeria monocytogenes, Escherichia coli, Salmonella typhimurium, Pseudomonas aeruginosa and Enterobacter sakazakii. Almost all isolates were sensitive to ampicillin, chloramphenicol, vancomycin and amoxicillin, and most of isolates exhibited resistance against tetracycline and vancomycin. The adhesion rates of LAB varied greatly. The results of the study suggested that the Lactobacillus acidophilus NCUA065001 have the important functional property of probiotic candidates to enhance gut integrity and could considered to be the potential antibiotic alternatives in the pig feed industry.

Effects of Dietary Supplementation of Lactobacillus acidophilus on Blood Parameters and Gut Health of Rabbits

This study aimed to evaluate the effects of Lactobacillus acidophilus D2/CSL (L-1 × 109 cfu/kg feed/day) on biochemical parameters, faecal score (FS), cecal pH, gut morphometry, microbiota and cecal short-chain fatty acid (SCFAs) in rabbits. Three zootechnical trials were performed and in each trial 30 rabbits were allotted to two groups; a probiotic group (L) and a control group (C). At slaughter (day 45), samples of blood, duodenum, jejunum, ileum, liver and spleen were collected and submitted to histomorphometric analyses. Blood biochemical analyses, cecal microbiota and SCFAs determination were also performed. In trial 1 and 3, L. acidophilus D2/CSL did not affect productive parameters (p > 0.05). However, L group of trial 1 showed a lower morbidity and mortality compared to the control. In trial 2, C group showed a higher daily feed intake (p = 0.018) and a positive statistical tendency for live weight and average daily gain (p = 0.068). On the contrary, albumin was higher and ALFA-1 globulin was lower in the C group compared to L (p < 0.05). In all the trials, FS, cecal pH, histomorphometry, microbiota and SCFAs were unaffected. In conclusion, L. acidophilus D2/CSL did not impair growth performances, gut and rabbit’s health, reducing morbidity and mortality.

Antimicrobial peptide production in response to gut microbiota imbalance

The gut microbiota presents essential functions in the immune response. The gut epithelium acts as a protective barrier and, therefore, can produce several antimicrobial peptides (AMPs) that can act against pathogenic microorganisms, including bacteria. Several factors cause a disturbance in gut microbiota, including the exacerbated and erroneous use of antibiotics. Antibiotic therapy has been closely related to bacterial resistance and is also correlated with undesired side-effects to the host, including the eradication of commensal bacteria. Consequently, this results in gut microbiota imbalance and inflammatory bowel diseases (IBD) development. In this context, AMPs in the gut epithelium play a restructuring role for gut microbiota. Some naturally occurring AMPs are selective for pathogenic bacteria, thus preserving the health microbiota. Therefore, AMPs produced by the host's epithelial cells represent effective molecules in treating gut bacterial infections. Bearing this in mind, this review focused on describing the importance of the host's AMPs in gut microbiota modulation and their role as anti-infective agents against pathogenic bacteria.

The Functional Roles of Lactobacillus acidophilus in Different Physiological and Pathological Processes

Probiotics are live microorganisms that can be consumed by humans in amounts sufficient to offer health-promoting effects. Owing to their various biological functions, probiotics are widely used in biological engineering, industry and agriculture, food safety, and the life and health fields. Lactobacillus acidophilus (L. acidophilus), an important human intestinal probiotic, was originally isolated from the human gastrointestinal tract and its functions have been widely studied ever since it was named in 1900. L. acidophilus has been found to play important roles in many aspects of human health. Due to its good resistance against acid and bile salts, it has broad application prospects in functional, edible probiotic preparations. In this review, we explore the basic characteristics and biological functions of L. acidophilus based on the research progress made thus far worldwide. Various problems to be solved regarding the applications of probiotic products and their future development are also discussed.

The Effect of Short-Term Consumption of Lactic Acid Bacteria on the Gut Microbiota in Obese People

Obesity is a problem of modern health care that causes the occurrence of many concomitant diseases: arterial hypertension, diabetes mellitus, non-alcoholic fatty liver disease, and cardiovascular diseases. New strategies for the treatment and prevention of obesity are being developed that are based on using probiotics for modulation of the gut microbiota. Our study aimed to evaluate the bacterial composition of the gut of obese patients before and after two weeks of lactic acid bacteria (Lactobacillus acidophilus, Lactiplantibacillus plantarum, Limosilactobacillus fermentum, and Lactobacillus delbrueckii) intake. The results obtained showed an increase in the number of members of the phylum Actinobacteriota in the group taking nutritional supplements, while the number of phylum Bacteroidota decreased in comparison with the control group. There has also been an increase in potentially beneficial groups: Bifidobacterium, Blautia, Eubacterium, Anaerostipes, Lactococcus, Lachnospiraceae ND3007, Streptococcus, Escherichia-Shigella, and Lachnoclostridium. Along with this, a decrease in the genera was demonstrated: Faecalibacterium, Pseudobutyrivibrio, Subdoligranulum, Faecalibacterium, Clostridium sensu stricto 1 and 2, Catenibacterium, Megasphaera, Phascolarctobacterium, and the Oscillospiraceae NK4A214 group, which contribute to the development of various metabolic disorders. Modulation of the gut microbiota by lactic acid bacteria may be one of the ways to treat obesity.

Probiotic activity traits in vitro and production of antimicrobial peptides by Lactobacillaceae isolates from pulque using Lactobacillus acidophilus NCFM as control

The objective of this work was to determine in vitro probiotic activity traits of 11 lactic acid bacteria (LAB) strains isolated from pulque obtained from three different locations in the Mexican states of Oaxaca and Puebla using the probiotic strain Lactobacillus acidophilus NCFM as a positive control, and to detect their production of antimicrobial peptides, including bacteriocins and peptidoglycan hydrolases (PGH). The LAB isolates were identified by sequencing of their 16S rRNA as belonging to four different genera of the Lactobacillaceae family: Lactiplantibacillus, Levilactobacillus, Lacticaseibacillus and Liquorilactobacillus, corresponding to the species plantarum, brevis, paracasei and ghanensis, respectively. Most of the strains showed resistance to high acidity (pH 2) and bile salts (0.5%), with survival rates up to 87 and 92%, respectively. In addition, most of the strains presented good antimicrobial activity against the foodborne pathogens Listeria monocytogenes, ECEC and Salmonella Typhi. The strain Liquorilactobacillus ghanensis RVG6, newly reported in pulque, presented an outstanding overall performance on the probiotic activity tests. In terms of their probiotic activity traits assessed in this work, the strains compared positively with the control L. acidophilus NCFM, which is a very-well documented probiotic strain. For the antimicrobial peptide studies, four strains presented bacteriocin-like mediated antibiosis and six had significant PGH activity, with two strains presenting outstanding overall antimicrobial peptide production: Lacticaseibacillus paracasei RVG3 and Levilactobacillus brevis UTMB2. The probiotic performance of the isolates was mainly dependent on strain specificity. The results obtained in this work can foster the revalorization of pulque as a functional natural product.

Valorization of household food wastes to lactic acid production: A response surface methodology approach to optimize fermentation process

Lactic acid is a valuable compound used in several industrial processes such as polymers, emulsifiers manufacturing, pharmaceutical, and cosmetic formulations. The present study aims to evaluate the potential use of food waste to produce lactic acid through fermentation, both by indigenous microbiota and by the bio-augmentation with two lactic acid bacteria, namely Lactobacillus plantarum BS17 and Lactobacillus casei BP2. Fermentation was studied both in batch and continuously fed anaerobic reactors at mesophilic conditions and a Response Surface Methodology approach was used to optimize the bioprocess performance and determine the environmental parameters (namely pH and time) that lead to the enhancement of lactic acid production during the batch fermentation by indigenous microorganisms. Results revealed an optimum set of conditions for lactic acid production at a pH value of 6.5 and a fermentation period of 3.5 days at 37 °C. Under these conditions lactic acid production reached a value of 23.07 g/L, which was very similar to the mathematically predicted ones, thus verifying the accuracy of the experimental design. This optimum set of conditions was further employed to examine the production of lactic acid under continuous fermentation operation. Furthermore, concentrations of volatile fatty acids and ethanol were monitored and found to be relatively low, with ethanol being the dominant by-product of fermentation, indicating the presence of heterofermentative bacteria in the food wastes. A final step of downstream process was performed resulting in the successful recovery of lactic acid with purity over 90%.

Complete Genome Sequence of Lactobacillus acidophilus LA-10A, a Promising Probiotic Strain Isolated from Fermented Mare's Milk

This report describes the whole-genome sequence of Lactobacillus acidophilus LA-10A, isolated from fermented mare’s milk. This strain has been widely consumed due to its excellent performance in the treatment and prevention of Helicobacter pylori infection. The genome sequence of LA-10A provides further molecular information about its features.

The effect of probiotics on gestational diabetes and its complications in pregnant mother and newborn: A systematic review and meta-analysis during 2010-2020

This study was aimed to evaluate the effect of probiotics consumption on gestational diabetes (GD) and its complications in pregnant mother and newborn. The study was registered on PROSPERO (CRD42021243409) and all the enrolled articles were collected from four databases (Medline, Scopus, Embase, and Google Scholar) as randomized controlled trials (RCTs) from 2010 to 2020. A total of 4865 study participants from 28 selected studies were included in this review. The present meta‐analysis showed that the consumption of probiotics supplementation has the potential to decrease GD‐predisposing metabolic parameters such as blood glucose level, lipid profile, inflammation, and oxidative markers which may reduce GD occurrence among pregnant women.

Efficacy of the incorporation between self-encapsulation and cryoprotectants on improving the freeze-dried survival of probiotic bacteria

AIMS

This study aimed to improve the viability of probiotic bacteria during freeze-drying by the combination of self-encapsulation and cryoprotectants.

METHODS AND RESULTS

Lactiplantibacillus plantarum VAL6 and Lactobacillus acidophilus VAR1 were exposed to environmental stresses including temperature, pH, and increased CO₂ concentration before performing freeze-drying with the addition of cryoprotectants. The results proved that tested stresses can stimulate the bacteria to synthesize more extracellular polymeric substances to form self-encapsulation that increases their freeze-dried viability. In combination with cryoprotectants to form double-layered microencapsulation, L. plantarum VAL6 stressed at pH 3.5 in combination with whey protein isolate could achieve the highest Improving Cell Viability of 4,361 fold, while L. acidophilus VAR1 stressed at 25^o C in combination with alginate gave a maximum Improving Cell Viability of 73.33 fold.

CONCLUSIONS

The combination of self-encapsulation and cryoprotectants significantly improves the freeze-dried viability of probiotics.

SIGNIFICANCE AND IMPACT OF THE STUDY

This is the first report that uses environmental stress to stimulate EPS synthesis for self-encapsulation formation combined with the addition of cryoprotectants to enhance to the freeze-dried survival of probiotics. This could be a novel approach in improving the viability of probiotic strains for various applications.

Recent Advances in Understanding the Structure and Function of the Human Microbiome

Trillions of microbes live within our bodies in a deep symbiotic relationship. Microbial populations vary across body sites, driven by differences in the environment, immunological factors, and interactions between microbial species. Major advances in genome sequencing enable a better understanding of microbiome composition. However, most of the microbial taxa and species of the human microbiome are still unknown. Without revealing the identity of these microbes as a first step, we cannot appreciate their role in human health and diseases. A shift in the microbial balance, termed dysbiosis, is linked to a broad range of diseases from simple colitis and indigestion to cancer and dementia. The last decade has witnessed an explosion in microbiome research that led to a better understanding of the microbiome structure and function. This understanding leads to potential opportunities to develop next-generation microbiome-based drugs and diagnostic biomarkers. However, our understanding is limited given the highly personalized nature of the microbiome and its complex and multidirectional interactions with the host. In this review, we discuss: (1) our current knowledge of microbiome structure and factors that shape the microbial composition, (2) recent associations between microbiome dysbiosis and diseases, and (3) opportunities of new microbiome-based therapeutics. We analyze common themes, promises, gaps, and challenges of the microbiome research.

Complete genome sequencing and comparative genomic analysis of Lactobacillus acidophilus C5 as a potential canine probiotics

Lactobacillus acidophilus is a gram-positive, microaerophilic, and acidophilic bacterial species. L. acidophilus strains in the gastrointestinal tracts of humans and other animals have been profiled, but strains found in the canine gut have not been studied yet. Our study helps in understanding the genetic features of the L. acidophilus C5 strain found in the canine gut, determining its adaptive features evolved to survive in the canine gut environment, and in elucidating its probiotic functions. To examine the canine L. acidophilus C5 genome, we isolated the C5 strain from a Korean dog and sequenced it using PacBio SMRT sequencing technology. A comparative genomic approach was used to assess genetic relationships between C5 and six other strains and study the distinguishing features related to different hosts. We found that most genes in the C5 strain were related to carbohydrate transport and metabolism. The pan-genome of seven L. acidophilus strains contained 2,254 gene families, and the core genome contained 1,726 gene families. The phylogenetic tree of the core genes in the canine L. acidophilus C5 strain was very close to that of two strains (DSM20079 and NCFM) from humans. We identified 30 evolutionarily accelerated genes in the L. acidophilus C5 strain in the ratio of non-synonymous to synonymous substitutions (dN/dS) analysis. Five of these thirty genes were associated with carbohydrate transport and metabolism. This study provides insights into genetic features and adaptations of the L. acidophilus C5 strain to survive the canine intestinal environment. It also suggests that the evolution of the L. acidophilus genome is closely related to the host's evolutionary adaptation process.

The inhibitory effect of a novel neem paste against cariogenic bacteria

Background

Dental caries is a major oral health problem, which associates with cariogenic bacteria. Streptococcus mutans and Lactobacillus acidophilus are facultative anaerobic bacteria that are found in tooth decay. Accordingly, neem leaf extract was developed due to its great anti-microbial property against many bacteria. The aim of this study was to determine anti-cariogenic properties of neem leaf extract in a novel paste preparation.

Material and Methods

The neem extract was derived from maceration of dry neem leaves in ethanol for 48 h. The ethanolic extract was subjected to chemical identification using GC-MS. Neem pastes were prepared from ethanolic extract mixed with polyethylene glycol paste with or without zinc oxide. S. mutans and L. acidophilus test were initiated at bacterial concentration of 108 CFU/ml. The antibacterial activity was then performed by disc diffusion method following by minimum bactericidal concentration (MBC) technique.

Results

GC-MS result displayed 35 compounds. Compounds found in the extract were n-Hexadecanoic acid (31.18%), Hentriacontane (18%), Phytol (16.79%). Disc diffusion showed that ethanolic extract and neem pastes inhibited growth of both bacteria. For MBC, neem paste with zinc oxide at concentration of neem 0.4 mg/ml was the most effective concentration on inhibiting S. mutans growth. Neem pastes and ethanolic extract at concentration of neem 6.25 mg/ml inhibited L. acidophilus growth.

Conclusions

The ethanolic neem leaf extract and novel neem pastes had antimicrobial effect on both S. mutans and L. acidophilus. By this property, neem paste could be developed for the application in dental field, i.e. pulp capping.

Key words:Neem, Azadirachta indica, antimicrobial, cariogenic bacteria.

Exploiting the Metabolism of the Gut Microbiome as a Vehicle for Targeted Drug Delivery to the Colon

The prevalence of colon-associated diseases has increased significantly over the past several decades, as evidenced by accumulated literature on conditions such as Crohn’s disease, irritable bowel syndrome, colorectal cancer, and ulcerative colitis. Developing therapeutics for these diseases is challenging due to physiological barriers of the colon, systemic side effects, and the intestinal environment. Therefore, in a search for novel methods to overcome some of these problems, researchers discovered that microbial metabolism by gut microbiotia offers a potential method for targeted drug delivery This overview highlights several drug delivery systems used to modulate the microbiota and improve colon-targeted drug delivery. This technology will be important in developing a new generation of therapies which harness the metabolism of the human gut microflora.

Turbidimetric definition of growth limits in probiotic Lactobacillus strains from the perspective of an adaptation strategy

The application of an adaptation strategy for probiotics, which may improve their stress tolerance, requires the identification of the growth range for each parameter tested. In this study, 4 probiotics (Lactobacillus acidophilus, Lacticaseibacillus casei, Lacticaseibacillus rhamnosus, and Lactiplantibacillus plantarum) were grown under different pH, NaCl, and sucrose concentrations at 25°C, 30°C, and 37°C. Turbidimetric growth curves were carried out and lag phase duration, maximum growth rate, and amplitude (i.e., the difference between initial and stationary phase optical density) were estimated. Moreover, cell morphology was observed, and cell length measured. The growth response, as well as the morphological changes, were quite different within the 4 species. The L. acidophilus was the most sensitive strain, whereas L. plantarum was shown to better tolerate a wide range of stressful conditions. Frequently, morphological changes occurred when the growth curve was delayed. Based on the results, ranges of environmental parameters are proposed that can be considered suboptimal for each strain, and therefore could be tested. The quantitative evaluation of the growth kinetics as well as the morphological observation of the cells can constitute useful support to the choice of the parameters to be used in an adaptation strategy, notwithstanding the need to verify the effect on viability both in model systems and in foods.

Selenium-Enriched Lactobacillus acidophilus Ameliorates Dextran Sulfate Sodium-Induced Chronic Colitis in Mice by Regulating Inflammatory Cytokines and Intestinal Microbiota

Aim: To evaluate the effect of Selenium-enriched Lactobacillus acidophilus (Se-enriched L. acidophilus) on dextran sulfate sodium (DSS)-induced colitis in mice. Methods: Mice were randomly divided into four groups: a control group, a control + Se-enriched L. acidophilus group, a chronic colitis group, and a chronic colitis + Se-enriched L. acidophilus group (n = 10 each group). The mice were sacrificed on the 26th day. The disease activity index, survival rates, and histological injury score were determined. Cytokines produced by lamina propria lymphocytes (LPLs), the selenium (Se) concentrations in serum and colon tissue and the mouse intestinal microbiota were evaluated. Results: Se-enriched L. acidophilus can improve histological injury and the disease activity index in mice with chronic colitis and reduce IL-1β, IL-6, IL-12p70, TNF-α, IL-23, IFN-γ, IL-17A, and IL-21 (P < 0.05) and increase IL-10 (P < 0.05) expression levels. Moreover, Se-enriched L. acidophilus can increase the β diversity of intestinal microbiota in mice with chronic colitis, significantly reduce the relative abundance of Lactobacillus and Romboutsia (P < 0.05), and significantly increase the relative abundance of Parasutterella (P < 0.05). Conclusions: Se-enriched L. acidophilus can improve DSS-induced chronic colitis by regulating inflammatory cytokines and intestinal microbiota.

Probiotic Lactobacilli in Fermented Dairy Products: Selective Detection, Enumeration and Identification Scheme

A selection of 36 commercial probiotic fermented dairy products from UK and Europe markets were evaluated for the numbers, types, and viability of Lactobacillus strains against the stated information on their packages. A comparative study was carried out on selectivity of MRS-Clindamycin, MRS-Sorbitol, and MRS-IM Maltose, to select the right medium for enumeration of probiotic Lactobacillus. Based on selectivity of medium for recovery of the targeted lactobacilli, and also simplicity of preparation, MRS-Clindamycin was chosen as the best medium for enumeration of probiotic Lactobacillus in fermented milks. The results of enumeration of lactobacilli showed that 22 out of a total 36 tested products contained more than 10⁶ colony-forming units/g at the end of their shelf life, which comply with the recommended minimum therapeutic level for probiotics. Rep-PCR using primer GTG-5 was applied for initial discrimination of isolated strains, and isolates, which presented different band profile, were placed in different groups. The isolated Lactobacillus spp. were identified mainly as Lactobacillus acidophilus, Lactobacillus casei, and Lactobacillus paracasei by analysis of partial sequences of the 16S ribosomal RNA and rpoA genes.

Probiotics-Live Biotherapeutics: a Story of Success, Limitations, and Future Prospects-Not Only for Humans

In livestock production, lactic acid bacteria (LAB) represent the most widespread microorganisms used as probiotics. For such critical use, these bacteria must be correctly identified and characterized to ensure their safety and efficiency. Recently, probiotics have become highly recognized as supplements for humans and in particular for animals because of their beneficial outcome on health improvement and well-being maintenance. Various factors, encompassing dietary and management constraints, have been demonstrated to tremendously influence the structure, composition, and activities of gut microbial communities in farm animals. Previous investigations reported the potential of probiotics in animal diets and nutrition. But a high rate of inconsistency in the efficiency of probiotics has been reported. This may be due, in a major part, to the dynamics of the gastrointestinal microbial communities. Under stressing surroundings, the direct-fed microbials may play a key role as the salient limiting factor of the severity of the dysbiosis caused by disruption of the normal intestinal balance. Probiotics are live microorganisms, which confer health benefits on the host by positively modifying the intestinal microflora. Thus, the aim of this review is to summarize and to highlight the positive influence of probiotics and potential probiotic microbe supplementation in animal feed with mention of several limitations.

Bacterial Peptidoglycan Fragments Differentially Regulate Innate Immune Signaling

The human innate immune system responds to both pathogen and commensal bacteria at the molecular level using bacterial peptidoglycan (PG) recognition elements. Traditionally, synthetic and commercially accessible PG monosaccharide units known as muramyl dipeptide (MDP) and N-glycolyl MDP (ng-MDP) have been used to probe the mechanism of innate immune activation of pattern recognition receptors, such as NOD-like receptors. However, bacterial PG is a dynamic and complex structure, with various chemical modifications and trimming mechanisms that result in the production of disaccharide-containing elements. These molecules pose as attractive targets for immunostimulatory screening; however, studies are limited because of their synthetic accessibility. Inspired by disaccharide-containing compounds produced from the gut microbe Lactobacillus acidophilus, a robust and scalable chemical synthesis of PG-based disaccharide ligands was implemented. Together with a monosaccharide PG library, compounds were screened for their ability to stimulate proinflammatory genes in bone-marrow-derived macrophages. The data reveal distinct gene induction patterns for monosaccharide and disaccharide PG units, suggesting that PG innate immune signaling is more complex than a one activator-one pathway program, as biologically relevant fragments induce transcriptional programs to different degrees. These disaccharide molecules will serve as critical immunostimulatory tools to more precisely define specialized innate immune regulatory mechanisms that distinguish between commensal and pathogenic bacteria residing in the microbiome.

Authenticity of probiotic foods and dietary supplements: A pivotal issue to address

The market of probiotic foods and supplements is growing rapidly but frequently the commercialized products are not compliant with their labels in terms of claimed probiotic strain(s) and labeled number of viable probiotic cells, thus mining the authenticity of these probiotic products.In this review, we provide an up-to-date overview of: (i) the current regulatory aspects, (ii) the consistency of probiotic foods and supplements with their labels, (iii) the implications of mislabeling on the quality, safety and functionality of these products and (iv) the available and most promising methods to assess the authenticity of these products, taking into account the need to discriminate among the different physiological states probiotics might be in the carrier matrices. It arises that authenticity of probiotic foods and supplements is an urgent issue, of industrial and legislation relevance, that need to be addressed. A plethora of methods are available to reach this goal, each with its own advantages and disadvantages. Protocols that combine the use of propidium monoazide (PMA) with metagenomics or polyphasic approaches including the PMA real time PCR or flow cytometry (for the viability assessment) and the whole genome sequence analysis (for the identification and typing of the probiotic strain) are the most promising that should be standardized and used by producers and regulators.

In Vivo Transcriptome of Lactobacillus acidophilus and Colonization Impact on Murine Host Intestinal Gene Expression

Lactobacillus acidophilus NCFM is a probiotic strain commonly used in dairy products and dietary supplements. Postgenome in vitro studies of NCFM thus far have linked potential key genotypes to its probiotic-relevant attributes, including gut survival, prebiotic utilization, host interactions, and immunomodulatory activities. To corroborate and extend beyond previous in vivo and in vitro functional studies, we employed a dual RNA sequencing (RNA-seq) transcriptomic approach to identify genes potentially driving the gut fitness and activities of L. acidophilus NCFM in vivo, and in parallel, examine the ileal transcriptional response of its murine hosts during monocolonization. Spatial expression profiling of NCFM from the ileum through the colon revealed a set of 134 core genes that were consistently overexpressed during gut transit. These in vivo core genes are predominantly involved in the metabolism of carbohydrates, amino acids, and nucleotides, along with mucus-binding proteins and adhesion factors, confirming their functionally important roles in nutrient acquisition and gut retention. Functional characterization of the highly expressed major S-layer-encoding gene established its indispensable role as a cell shape determinant and maintenance of cell surface integrity, essential for viability and probiotic attributes. Host colonization by L. acidophilus resulted in significant downregulation of several proinflammatory cytokines and tight junction proteins. Genes related to redox signaling, mucin glycosylation, and circadian rhythm modulation were induced, suggesting impacts on intestinal development and immune functions. Metagenomic analysis of NCFM populations postcolonization demonstrated the genomic stability of L. acidophilus as a gut transient and further established its safety as a probiotic and biotherapeutic delivery platform.IMPORTANCE To date, our basis for comprehending the probiotic mechanisms of Lactobacillus acidophilus, one of the most widely consumed probiotic microbes, was largely limited to in vitro functional genomic studies. Using a germfree murine colonization model, in vivo-based transcriptional studies provided the first view of how L. acidophilus survives in the mammalian gut environment, including gene expression patterns linked to survival, efficient nutrient acquisition, stress adaptation, and host interactions. Examination of the host ileal transcriptional response, the primary effector site of L. acidophilus, has also shed light into the mechanistic roles of this probiotic microbe in promoting anti-inflammatory responses, maintaining intestinal epithelial homeostasis and modulation of the circadian-metabolic axis in its host.