Potential Application Of Probiotics Research Articles

Probiotics in the Management of Vulvovaginal Candidosis.

Vulvovaginal candidosis (VVC) represents a frequent and cumbersome vaginal infection. Recurrent and/or persistent infections remain common among a significant number of patients despite the use of antifungals. Probiotics offer a promising adjunctive or alternative therapeutic strategy to antifungals in the management of VVC. We aimed to explore and thoroughly examine the various roles and potential applications of probiotics in VVC. A comprehensive literature search was conducted to identify relevant clinical trials and systematic reviews that examine the effectiveness of probiotics in the treatment and prevention of VVC and recurrent VVC (rVVC). Following the initial screening of 4563 articles, a total of 25 clinical studies and seven systematic reviews were finally included in this analysis. The studies reviewed provide a generally positive yet inconsistent view of the efficacy of probiotics in managing VVC, including clinical, mycological response, and prevention perspectives. Nonetheless, fluconazole remains more effective than probiotics in treating VVC, while the combination of the two seems to reduce recurrence and improve symptoms significantly. For prevention, probiotics seem to improve vaginal health and reduce symptoms, while safety and tolerability are consistently reported across the studies, affirming that probiotics represent a low-risk intervention. However, clear conclusions are difficult to establish since relative studies explore different clinical endpoints and follow-up times, variable populations are included, different probiotics are used, and diverse schedules and regimens are administered. We propose that future studies should study the benefit of probiotics in well-defined categories such as (1) treatment with acute probiotics instead of antifungals, (2) adjuvant probiotic therapy together or after antifungals, and (3) VVC recurrence prevention using probiotics.

Effects of Limosilactobacillus reuteri strains PTA-126787 and PTA-126788 on intestinal barrier integrity and immune homeostasis in an alcohol-induced leaky gut model

Intestinal barrier is a first line of defense that prevents entry of various harmful substances from the lumen into the systemic environment. Impaired barrier function with consequent translocation of harmful substances into systemic circulation (“leaky gut”) is a central theme in many gastrointestinal, autoimmune, mental, and metabolic diseases. Probiotics have emerged as a promising strategy to maintain intestinal integrity and address “leaky gut”. Using in silico, in vitro and avian in vivo analyses, we previously showed that two novel L. reuteri strains, PTA-126787 (L. reuteri 3630) and PTA-126788 (L. reuteri 3632), isolated from broiler chickens possess favorable safety profiles. Consistent with a recent study, here we show that L. reuteri 3630 and 3632 are phylogenetically similar to human L. reuteri strains. Daily administration of high doses of L. reuteri 3630 and 3632 to Sprague Dawley rats for 28 days was found to be safe with no adverse effects. More importantly, administration of L. reuteri 3630 and 3632 significantly reduced markers associated with alcohol-induced leaky gut, by downregulating inflammatory cytokines and upregulating anti-inflammatory cytokines in an alcohol model of leaky gut in mice. While L. reuteri 3630 cells and supernatant showed no activation, L. reuteri 3632 cells but not supernatant showed activation of AhR, a key transcription factor that regulates gut and immune homeostasis. L. reuteri 3630 is creamish white in morphology typical of Lactobacillus species and L. reuteri 3632 displays a unique orange pigmentation, which was stable even after passaging for 480 generations. We identified a rare polyketide biosynthetic gene cluster in L. reuteri 3632 that likely encodes for the orange-pigmented secondary metabolite. Similar to L. reuteri 3632 cells, the purified orange metabolite activated AhR. All together, these data provide evidence on the phylogenetic relatedness, safety, efficacy, and one of the likely mechanisms of action of L. reuteri 3630 and 3632 for potential probiotic applications to address “leaky gut” and associated pathologies in humans.

Comprehensive characterization of γ-aminobutyric acid (GABA) production by Levilactobacillus brevis CRL 2013: insights from physiology, genomics, and proteomics.

Levilactobacillus brevis CRL 2013, a plant-derived lactic acid bacterium (LAB) with immunomodulatory properties, has emerged as an efficient producer of γ-aminobutyric acid (GABA). Notably, not all LAB possess the ability to produce GABA, highlighting the importance of specific genetic and environmental conditions for GABA synthesis. This study aimed to elucidate the intriguing GABA-producing machinery of L. brevis CRL 2013 and support its potential for safe application through comprehensive genome analysis. A comprehensive genome analysis of L. brevis CRL 2013 was performed to identify the presence of antibiotic resistance genes, virulence markers, and genes associated with the glutamate decarboxylase system, which is essential for GABA biosynthesis. Then, an optimized chemically defined culture medium (CDM) was supplemented with monosodium glutamate (MSG) and yeast extract (YE) to analyze their influence on GABA production. Proteomic and transcriptional analyses were conducted to assess changes in protein and gene expression related to GABA production. The absence of antibiotic resistance genes and virulence markers in the genome of L. brevis CRL 2013 supports its safety for potential probiotic applications. Genes encoding the glutamate decarboxylase system, including two gad genes (gadA and gadB) and the glutamate antiporter gene (gadC), were identified. The gadB gene is located adjacent to gadC, while gadA resides separately on the chromosome. The transcriptional regulator gadR was found upstream of gadC, with transcriptional analyses demonstrating cotranscription of gadR with gadC. Although MSG supplementation alone did not activate GABA synthesis, the addition of YE significantly enhanced GABA production in the optimized CDM containing glutamate. Proteomic analysis revealed minimal differences between MSG-supplemented and non-supplemented CDM cultures, whereas YE supplementation resulted in significant proteomic changes, including upregulation of GadB. Transcriptional analysis confirmed increased expression of gadB and gadR upon YE supplementation, supporting its role in activating GABA production. These findings provide valuable insights into the influence of nutrient composition on GABA production. Furthermore, they unveil the potential of L. brevis CRL 2013 as a safe, nonpathogenic strain with valuable biotechnological traits which can be further leveraged for its probiotic potential in the food industry.

Strategies to Enhance Cultivation of Anaerobic Bacteria from Gastrointestinal Tract of Chicken.

The gastrointestinal tract (GIT) of chicken is a complex ecosystem harboring trillions of microbes that play a pivotal role in the host's physiology, digestion, nutrient absorption, immune system maturation, and prevention of pathogen intrusion. For optimal animal health and productivity, it is imperative to characterize these microorganisms and comprehend their role. While the GIT of poultry holds a reservoir of microorganisms with potential probiotic applications, most of the diversity remains unexplored. To enhance our understanding of uncultured microbial diversity, concerted efforts are required to bring these microorganisms into culture. Isolation and cultivation of GIT-colonizing microorganisms yield reproducible material, including cells, DNA, and metabolites, offering new insights into metabolic processes in the environment. Without cultivation, the role of these organisms in their natural settings remains unclear and limited to a descriptive level. Our objective is to implement cultivation strategies aimed at improving the isolation of a diverse range of anaerobic microbes from the chicken's GIT, leveraging multidisciplinary knowledge from animal physiology, animal nutrition, metagenomics, feed biochemistry, and modern cultivation strategies. Additionally, we aim to implement the use of proper practices for sampling, transportation, and media preparation, which are known to influence isolation success. Appropriate methodologies should ensure a consistent oxygen-free environment, optimal atmospheric conditions, appropriate host incubation temperature, and provision for specific nutritional requirements in alignment with their distinctive needs. By following these methodologies, cultivation will not only yield reproducible results for isolation but will also facilitate isolation procedures, thus fostering a comprehensive understanding of the intricate microbial ecosystem within the chicken's GIT.

Bacillus subtilis SOM8 isolated from sesame oil meal for potential probiotic application in inhibiting human enteropathogens

BackgroundWhile particular strains within the Bacillus species, such as Bacillus subtilis, have been commercially utilised as probiotics, it is critical to implement screening assays and evaluate the safety to identify potential Bacillus probiotic strains before clinical trials. This is because some Bacillus species, including B. cereus and B. anthracis, can produce toxins that are harmful to humans.ResultsIn this study, we implemented a funnel-shaped approach to isolate and evaluate prospective probiotics from homogenised food waste – sesame oil meal (SOM). Of nine isolated strains with antipathogenic properties, B. subtilis SOM8 displayed the most promising activities against five listed human enteropathogens and was selected for further comprehensive assessment. B. subtilis SOM8 exhibited good tolerance when exposed to adverse stressors including acidity, bile salts, simulated gastric fluid (SGF), simulated intestinal fluid (SIF), and heat treatment. Additionally, B. subtilis SOM8 possesses host-associated benefits such as antioxidant and bile salt hydrolase (BSH) activity. Furthermore, B. subtilis SOM8 contains only haemolysin toxin genes but has been proved to display partial haemolysis in the test and low cytotoxicity in Caco-2 cell models for in vitro evaluation. Moreover, B. subtilis SOM8 intrinsically resists only streptomycin and lacks plasmids or other mobile genetic elements. Bioinformatic analyses also predicted B. subtilis SOM8 encodes various bioactives compound like fengycin and lichendicin that could enable further biomedical applications.ConclusionsOur comprehensive evaluation revealed the substantial potential of B. subtilis SOM8 as a probiotic for targeting human enteropathogens, attributable to its exceptional performance across selection assays. Furthermore, our safety assessment, encompassing both phenotypic and genotypic analyses, showed B. subtilis SOM8 has a favourable preclinical safety profile, without significant threats to human health. Collectively, these findings highlight the promising prospects of B. subtilis SOM8 as a potent probiotic candidate for additional clinical development.

Comprehensive analysis of the microbiome in Apis cerana honey highlights honey as a potential source for the isolation of beneficial bacterial strains.

Honey is a nutritious food made by bees from nectar and sweet deposits of flowering plants and has been used for centuries as a natural remedy for wound healing and other bacterial infections due to its antibacterial properties. Honey contains a diverse community of bacteria, especially probiotic bacteria, that greatly affect the health of bees and their consumers. Therefore, understanding the microorganisms in honey can help to ensure the quality of honey and lead to the identification of potential probiotic bacteria. Herein, the bacteria community in honey produced by Apis cerana was investigated by applying the next-generation sequencing (NGS) method for the V3-V4 hypervariable regions of the bacterial 16S rRNA gene. In addition, lactic acid bacteria (LAB) in the honey sample were also isolated and screened for in vitro antimicrobial activity. The results showed that the microbiota of A. cerana honey consisted of two major bacterial phyla, Firmicutes (50%; Clostridia, 48.2%) and Proteobacteria (49%; Gammaproteobacteria, 47.7%). Among the 67 identified bacterial genera, the three most predominant genera were beneficial obligate anaerobic bacteria, Lachnospiraceae (48.14%), followed by Gilliamella (26.80%), and Enterobacter (10.16%). Remarkably, among the identified LAB, Lactobacillus kunkeei was found to be the most abundant species. Interestingly, the isolated L. kunkeei strains exhibited antimicrobial activity against some pathogenic bacteria in honeybees, including Klebsiella spp., Escherichia coli, Enterococcus faecalis, Pseudomonas aeruginosa and Staphylococcus aureus. This underscores the potential candidacy of L. kunkeei for developing probiotics for medical use. Taken together, our results provided new insights into the microbiota community in the A. cerana honey in Hanoi, Vietnam, highlighting evidence that honey can be an unexplored source for isolating bacterial strains with potential probiotic applications in honeybees and humans.

Probiotic-Induced Modulation of Microbiota Composition and Antibiotic Resistance Genes Load, an In Vitro Assessment.

The imbalance of the gut microbiota (GM) is known as dysbiosis and is associated with disorders such as obesity. The increasing prevalence of microorganisms harboring antibiotic resistance genes (ARG) in the GM has been reported as a potential risk for spreading multi-drug-resistant pathogens. The objective of this work was the evaluation, in a fecal culture model, of different probiotics for their ability to modulate GM composition and ARG levels on two population groups, extremely obese (OB) and normal-weight (NW) subjects. Clear differences in the basal microbiota composition were observed between NW and OB donors. The microbial profile assessed by metataxonomics revealed the broader impact of probiotics on the OB microbiota composition. Also, supplementation with probiotics promoted significant reductions in the absolute levels of tetM and tetO genes. Regarding the blaTEM gene, a minor but significant decrease in both donor groups was detected after probiotic addition. A negative association between the abundance of Bifidobacteriaceae and the tetM gene was observed. Our results show the ability of some of the tested strains to modulate GM. Moreover, the results suggest the potential application of probiotics for reducing the levels of ARG, which constitutes an interesting target for the future development of probiotics.

Seasonal variations of airborne microbial diversity in waste transfer stations and preventive effect on Streptococcus pneumoniae induced pulmonary inflammation

Environment, location, and season are important factors that influence the microbiological community, yet, little research on airborne microorganisms in waste transfer stations (WTSs). Here, the airborne bacterial and fungal communities at four WTSs during different seasons were analyzed by high-throughput sequencing. The bacteria were isolated by cultural method and screened bacterium alleviate inflammation induced by Streptococcus pneumoniae (Spn) by regulating gut microbiome. The results revealed that collected bioaerosols from the WTSs varied significantly by location and season. Proteobacteria and Pseudomonadota are prevalent in summer and winter, respectively. Ascomycota was predominant in two seasons. Hazard quotients for adults from four WTSs were below one. Three selected potential probiotics were formulated into a microbial preparation with a carrier that effectively prevented inflammation in bacterial and animal experiments. The expression levels of interleukin-1β, interleukin-6, and tumor necrosis factor-α in Pre group (0.11, 0.17, and 0.48-fold) were significantly lower than Spn group (2.75, 1.71, and 5.01-fold). These mechanisms are associated with changes in gut microbiota composition and short-chain fatty acids (SCFAs) levels, such as affecting Lachnospiraceae lachnospira abundance and acetic acid content. This study provides insights into the potential application of probiotics derived from WTSs as an alternative approach to preventing respiratory infections.

Review on application of probiotics in poultry farm

Poultry farming, raising of birds domestically or commercially, primarily for meat and eggs but also for feathers. In poultry industry, probiotics applications have widely been shown to improve the barrier function of intestine and reduce pathogenic problems in gastrointestinal tract thus leading to the enhancement of immune response and replacement of sub-therapeutic antibiotics. Probiotics, the novel feed or food supplements are naturally occurring beneficial live microbes including bacteria, fungi and yeasts. Probiotics are proven to improve the health and wellbeing of birds. As a group of growth promoters, the addition of probiotics to the diet of poultry has been found to improve growth performance, feed conversion efficiency, immune responses and help in combating enteric pathogens. The addition of probiotics to poultry diet also improves egg production in layers. Three basic mechanisms of probiotics include competitive exclusion of pathogenic microbes, production of antibacterial substances and immune modulation of host. Generally, live a pathogenic microbial strain, singly or as multistrain probiotics, belonging to genus Lactobacillus, Streptococcus, Bacillus, Enterococcus, Pediococcus, Aspergillus and Saccharomyces are used in poultry. The injudicious and prolific use of sub-therapeutic levels of antibiotics in animal feed to suppress or eliminate harmful organisms, and to improve growth and feed efficiency, have paved way for their presence as residues in animal by-products and have also given rise to drug resistant microorganisms. Because of public health concerns, nowadays, the use of probiotics as substitute for antibiotics in poultry production has become an area of great interest. The present article reviews the beneficial effects and potential applications of probiotics or direct fed microbial (DFM) on health and production performances in poultry.

The Applications and challenges of Probiotics/ Postbiotics in Cosmetic and personal care products

Probiotics, defined as “live microorganisms that, when administered in adequate amounts, confer a health benefit on the host,” are becoming increasingly popular and marketable. However, too many products labeled as probiotics fail to comply with the defining characteristics. In recent years, the cosmetic industry has increased the number of products classified as probiotics. While there are several potential applications for probiotics in personal care products, e.g., oral, skin, and personal care, proper regulation of the labeling and marketing standards is still required to guarantee that consumers are indeed purchasing a probiotic product. Postbiotics were defined as a “preparation of inanimate microorganisms and/or their components that confers a health benefit on the target host.” Actually, most of the cosmetic industry’s probiotic products belong to inactivated probiotics or postbiotics products. This review explores the current market, regulatory aspects, and potential applications of probiotics in the personal care industry.

Effects of probiotics on hypertension.

Emerging data have suggested that probiotics had good potential in regulating intestinal flora and preventing hypertension. Some studies in human and animal models have demonstrated probiotic intervention could attenuate hypertension, regulate intestinal flora to increase the abundance of beneficial bacteria, and regulate intestinal microbial metabolites such as trimethylamine oxide, short-chain fatty acids, and polyphenols. However, there is still some debate as to whether probiotics exert effective benefits. These recently published reviews did not systematically expound on the heterogeneity between the effect and mechanism of probiotics with different types, doses, and carriers to exert antihypertensive effects, as well as the possible application of probiotics in the prevention and treatment of hypertension in food and clinic. Here we try to systematically review the association between hypertension and intestinal microflora, the effect of probiotics and their metabolites on hypertension, and the recent research progress on the specific mechanism of probiotics on hypertension. In addition, we also summarized the potential application of probiotics in antihypertension. Future challenges include elucidating the functions of metabolites produced by microorganisms and their downstream pathway or molecules, identifying specific strains, not just microbial communities, and developing therapeutic interventions that target hypertension by modulation of gut microbes and metabolites.

In silico, in vitro and in vivo characterization of host-associated Latilactobacillus curvatus strains for potential probiotic applications in farmed Atlantic salmon (Salmo salar)

Salmon aquaculture is the fastest growing animal protein production system in the world; however, intensive farming leads to poor weight gain, stress, and disease outbreaks. Probiotics offer the potential to enhance growth performance and feed efficiency in Atlantic salmon, as well as immunostimulate fish against common pathogens, benefitting farmers and consumers with more efficient production. Here, we isolated and identified 900 native microbial isolates including 18 Lactobacilli from the farmed salmon intestines. Based on whole-genome sequencing and phylogenetic analysis, the Lactobacillus candidates belonged to Latilactobacillus curvatus (L. curvatus) species and formed two distinct phylogenetic groups. Using bioinformatics and in vitro analyses, we selected two candidates L. curvatus ATCC PTA-127116 and L. curvatus ATCC PTA-127117, which showed desirable safety and probiotic properties. The two L. curvatus candidates were evaluated for safety and efficacy (higher final weight) in Atlantic salmon alongside spore-forming Bacilli isolated from salmon, poultry, and swine. All the tested candidates were safe to salmon with no adverse effects. While we did not see efficacy in any Bacillus supplemented groups, compared to untreated group, the group administered with the two L. curvatus strains consortium in feed for seven weeks in freshwater showed indicators of improvement in final body weight by 4.2%. Similarly, the two L. curvatus candidates were also evaluated for safety and efficacy in Atlantic salmon in saltwater; the group administered with the two L. curvatus strains consortium in feed for 11 weeks showed indicators of improvement in final body weight by 4.7%. Comprehensive metabolomics analyses in the presence of different prebiotics and/or additives identified galactooligosaccharide as a potential prebiotic to enhance the efficacy of two L. curvatus candidates. All together, these data provide comprehensive genomic, phenotypic and metabolomic evidence of safety and desirable probiotic properties as well as indicators of in vivo efficacy of two novel endogenous L. curvatus candidates for potential probiotic applications in Atlantic salmon. The in vivo findings need to be confirmed in larger performance studies, including field trials.

Probiotics ameliorate growth retardation of glyphosate by regulating intestinal microbiota and metabolites in crucian carp (Carassius auratus)

Glyphosate (GLY) contamination widely occurred in aquatic environments including aquaculture systems and raised hazard to aquatic organisms such as fish. Probiotics have been reported to alleviate contaminants-induced toxicity. However, whether probiotics could reduce the health risk of GLY to fish remain unknown. Here we investigated the impacts of GLY on crucian carp (Carassius auratus) by focusing on the protective roles of two commonly used aquaculture probiotics, Bacillus coagulans (BC) and Clostridium butyricum (CB). Exposure to GLY significantly caused growth retardation and reduced visceral fat and intestinal lipase activity in crucian carp. 16S rRNA sequencing indicated that dysbiosis of Bacteroidetes at phylum level and Flavobacterium at genus level might be primarily responsible for GLY-induced negative growth performance. High throughput targeted quantification for metabolites revealed that GLY changed intestinal metabolites profiles, especially the reduced bile acids and short-chain fatty acids. However, the addition of BC or CB effectively attenuated the adverse effects above by remodeling the gut microbiota composition and improving microbial metabolism. The present study provides novel evidence for ameliorating the harmful effects of GLY on fish species by adding probiotics, which highlights the potential application of probiotics in reducing the health risks of GLY in aquatic environment.

Emerging story of gut dysbiosis in spondyloarthropathy: From gastrointestinal inflammation to spondyloarthritis.

As a set of inflammatory disorders, spondyloarthritis (SpA) exhibits distinct pathophysiological, clinical, radiological, and genetic characteristics. Due to the extra-articular features of this disorder, early recognition is crucial to limiting disability and improving outcomes. Gut dysbiosis has been linked to SpA development as evidence grows. A pathogenic SpA process is likely to occur when a mucosal immune system interacts with abnormal local microbiota, with subsequent joint involvement. It is largely unknown, however, how microbiota alterations predate the onset of SpA within the “gut-joint axis”. New microbiome therapies, such as probiotics, are used as an adjuvant therapy in the treatment of SpA, suggesting that the modulation of intestinal microbiota and/or intestinal barrier function may contribute to the prevention of SpA. In this review, we highlight the mechanisms of SpA by which the gut microbiota impacts gut inflammation and triggers the activation of immune responses. Additionally, we analyze the regulatory role of therapeutic SpA medication in the gut microbiota and the potential application of probiotics as adjunctive therapy for SpA.

In Vitro assessment of anti-Campylobacter activity of lactobacillus strains isolated from canine rectal swabs

BackgroundCampylobacteriosis is currently the most frequently reported zoonosis. Dogs, especially puppies or those with diarrhea, are considered a possible source of human infection. Probiotic bacteria, such as Lactobacillus species, seem to be a valuable tool in controlling of intestinal pathogenic microorganisms in dogs. The main purpose of this study was to assess the anti-Campylobacter activity and some probiotic properties, like ability to produce H2O2, bile salt and low pH tolerance of Lactobacillus strains isolated from gastrointestinal tract of healthy dogs.ResultsA total of 39 rectal swabs derived from healthy dogs and 19 from dogs with diarrhea were examined to detect Lactobacillus and Campylobacter bacteria respectively. In total, 30 strains of Lactobacillus genus and four strains of Campylobacter genus were isolated and identified. Of the 30 strains of Lactobacillus, 22 showed an inhibitory effect towards Campylobacter. Four strains with the strongest antagonism towards Campylobacter bacteria (L. salivarius 25 K/L/1, L. rhamnosus 42 K/L/2, L. sakei 50 K/L/1 and L. agilis 55 K/L/1) were selected to assess their potential probiotic traits. Three out of four analyzed strains produced extracellular H2O2. All displayed very good or moderate survival at pH 3.0 and 2.0 and showed high tolerance to 0.5% and 1% bile salts.ConclusionsAmong selected Lactobacillus strains, all may have a potential probiotic application in reducing Campylobacter spp. in dogs and thus prevent transmission of infection to humans, although the best candidate for probiotic seems to be L. sakei 50 K/L/1. Further in vitro and in vivo studies are needed.

In silico, in vitro and in vivo safety evaluation of Limosilactobacillus reuteri strains ATCC PTA-126787 & ATCC PTA-126788 for potential probiotic applications.

The last two decades have witnessed a tremendous growth in probiotics and in the numbers of publications on their potential health benefits. Owing to their distinguishing beneficial effects and long history of safe use, species belonging to the Lactobacillus genus are among the most widely used probiotic species in human food and dietary supplements and are finding increased use in animal feed. Here, we isolated, identified, and evaluated the safety of two novel Limosilactobacillus reuteri (L. reuteri) isolates, ATCC PTA-126787 & ATCC PTA-126788. More specifically, we sequenced the genomes of these two L. reuteri strains using the PacBio sequencing platform. Using a combination of biochemical and genetic methods, we identified the two strains as belonging to L. reuteri species. Detailed in silico analyses showed that the two strains do not encode for any known genetic sequences of concern for human or animal health. In vitro assays confirmed that the strains are susceptible to clinically relevant antibiotics and do not produce potentially harmful by-products such as biogenic amines. In vitro bile and acid tolerance studies demonstrated that the two strains have similar survival profiles as the commercial L. reuteri probiotic strain DSM 17938. Most importantly, daily administration of the two probiotic strains to broiler chickens in drinking water for 26 days did not induce any adverse effect, clinical disease, or histopathological lesions, supporting the safety of the strains in an in vivo avian model. All together, these data provide in silico, in vitro and in vivo evidence of the safety of the two novel candidates for potential probiotic applications in humans as well as animals.

Genome Mining for Antimicrobial Compounds in Wild Marine Animals-Associated Enterococci.

New ecosystems are being actively mined for new bioactive compounds. Because of the large amount of unexplored biodiversity, bacteria from marine environments are especially promising. Further, host-associated microbes are of special interest because of their low toxicity and compatibility with host health. Here, we identified and characterized biosynthetic gene clusters encoding antimicrobial compounds in host-associated enterococci recovered from fecal samples of wild marine animals remote from human-affected ecosystems. Putative biosynthetic gene clusters in the genomes of 22 Enterococcus strains of marine origin were predicted using antiSMASH5 and Bagel4 bioinformatic software. At least one gene cluster encoding a putative bioactive compound precursor was identified in each genome. Collectively, 73 putative antimicrobial compounds were identified, including 61 bacteriocins (83.56%), 10 terpenes (13.70%), and 2 (2.74%) related to putative nonribosomal peptides (NRPs). Two of the species studied, Enterococcus avium and Enterococcus mundtti, are rare causes of human disease and were found to lack any known pathogenic determinants but yet possessed bacteriocin biosynthetic genes, suggesting possible additional utility as probiotics. Wild marine animal-associated enterococci from human-remote ecosystems provide a potentially rich source for new antimicrobial compounds of therapeutic and industrial value and potential probiotic application.

Effects of Anaerobic Fermentation on Black Garlic Extract by Lactobacillus: Changes in Flavor and Functional Components.

The purpose of this study is to investigate the potential application of probiotics in the development of novel functional foods based on black garlic. The single-factor analysis (extraction temperatures, solid-to-liquid ratios, and extraction times) and the response surface methodology were firstly used to optimize hot water extraction of soluble solids from black garlic. The optimal extraction conditions were temperature 99.96°C, solid-to-liquid ratio 1:4.38 g/ml, and extracting 2.72 h. The effects of Lactobacillus (Lactobacillus plantarum, Lactobacillus rhamnosus, and co-culture of them) fermentation on the physicochemical properties of black garlic extract broth were studied for the first time. Artificial and electronic sensory evaluations demonstrated that fermentation significantly influenced the sensory characteristics. The variations of metabolites in different broth samples (S1, unfermented; S2, 1-day fermentation by L. plantarum; S3, 2-day fermentation by L. rhamnosus; and S4, 1-day fermentation by co-cultured Lactobacillus) were further investigated by gas chromatography-mass spectrometry and liquid chromatography-mass spectrometry/mass spectrometry analysis. As a result, Lactobacillus fermentation significantly reduced the pH; increased the contents of the total acid, amino nitrogen, total polyphenol, and total flavonoid; and reduced the content of 5-hydroxymethylfurfural (a carcinogenic component) by 25.10–40.81% in the black garlic extract. The contents of several components with unpleasant baking flavors (e.g., furfural, 2-acetylfuran, and 5-methyl furfural) were reduced, whereas the contents of components with green grass, floral, and fruit aromas were increased. More importantly, the contents of several functional components including lactic acid, Gly-Pro-Glu, sorbose, and α-CEHC (3,4-dihydro-6-hydroxy-2,5,7,8-tetramethyl-2H-1-benzopyran-2-propanoic acid) were increased after Lactobacillus fermentation. The results demonstrated the potential of probiotic fermentation to improve the quality of black garlic. This work will provide an insight into the strategic design of novel black garlic products and facilitate the application of black garlic in functional foods.

Selection of Potential Yeast Probiotics and a Cell Factory for Xylitol or Acid Production from Honeybee Samples.

Excessive use of antibiotics has detrimental consequences, including antibiotic resistance and gut microbiome destruction. Probiotic-rich diets help to restore good microbes, keeping the body healthy and preventing the onset of chronic diseases. Honey contains not only prebiotic oligosaccharides but, like yogurt and fermented foods, is an innovative natural source for probiotic discovery. Here, a collection of three honeybee samples was screened for yeast strains, aiming to characterize their potential in vitro probiotic properties and the ability to produce valuable metabolites. Ninety-four isolates out of one-hundred and four were able to grow at temperatures of 30 °C and 37 °C, while twelve isolates could grow at 42 °C. Fifty-eight and four isolates displayed the ability to grow under stimulated gastrointestinal condition, at pH 2.0–2.5, 0.3% (w/v) bile salt, and 37 °C. Twenty-four isolates showed high autoaggregation of 80–100% and could utilize various sugars, including galactose and xylose. The cell count of these isolates (7–9 log cfu/mL) was recorded and stable during 6 months of storage. Genomic characterization based on the internal transcribed spacer region (ITS) also identified four isolates of Saccharomyces cerevisiae displayed good ability to produce antimicrobial acids. These results provided the basis for selecting four natural yeast isolates as starter cultures for potential probiotic application in functional foods and animal feed. Additionally, these S. cerevisiae isolates also produced high levels of acids from fermented sugarcane molasses, an abundant agricultural waste product from the sugar industry. Furthermore, one of ten identified isolates of Meyerozyma guilliermondiii displayed an excellent ability to produce a pentose sugar xylitol at a yield of 0.490 g/g of consumed xylose. Potentially, yeast isolates of honeybee samples may offer various biotechnological advantages as probiotics or metabolite producers of multiproduct-based lignocellulosic biorefinery.

Asthma in the Precision Medicine Era: Biologics and Probiotics.

Asthma is a major global health issue. Over 300 million people worldwide suffer from this chronic inflammatory airway disease. Typical clinical symptoms of asthma are characterized by a recurrent wheezy cough, chest tightness, and shortness of breath. The main goals of asthma management are to alleviate asthma symptoms, reduce the risk of asthma exacerbations, and minimize long-term medicinal adverse effects. However, currently available type 2 T helper cells (Th2)-directed treatments are often ineffective due to the heterogeneity of the asthma subgroups, which manifests clinically with variable and poor treatment responses. Personalized precision therapy of asthma according to individualized clinical characteristics (phenotype) and laboratory biomarkers (endotype) is the future prospect. This mini review discusses the molecular mechanisms underlying asthma pathogenesis, including the hot sought-after topic of microbiota, add-on therapies and the potential application of probiotics in the management of asthma.