A comprehensive investigation of the medicinal efficacy of antimicrobial fusion peptides expressed in probiotic bacteria for the treatment of pan drug-resistant (PDR) infections

The present work aimed to examine the intracellular antibacterial efficacy of Recombinant Lactobacillus acidophilus/antimicrobial peptides (AMPs) Melittin and Alyteserin-1a, specifically targeting Gram-negative bacteria. The first assessment was to determine the minimum inhibitory concentration (MIC) and minimum bactericidal concentration (MBC) of Recombinant L. acidophilus/AMPs versus Gram-negative and Gram-positive bacteria. In addition, the researchers examined the in vitro viability and safety of AMPs generated by L. acidophilus. The experiments included exposing the AMPs to elevated temperatures, proteases, cationic salts at physiological levels, and specific pH settings. The safety aspect was evaluated using hemolytic analysis utilizing sheep erythrocytes; cytotoxicity assays employing cell lines, and experiments on beneficial gut lactobacilli. An experiment was done using a time-kill method to assess the intracellular antibacterial efficacy of Recombinant L. acidophilus/AMPs compared to pathogenic varieties in HEp-2 cells. Previous investigations have shown that the MBC levels of recombinant L. acidophilus/AMPs were consistently two to four times higher than the equivalent MIC values when evaluated versus Gram-negative bacteria. Furthermore, the stability of the Recombinant L. acidophilus/AMPs showed variability when exposed to elevated temperatures (70 and 90 ℃), treated with protease enzymes (proteinase K, lysozyme), exposed to higher concentrations of physiological salts (150 mM NaCl and 2 mM MgCl2), and varying pH levels (ranging from 4.0 to 9.0). The recombinant L. acidophilus/AMPs are non-hemolytic towards sheep erythrocytes, exhibit little cytotoxicity in RAW 264.7 and HEp-2 cells, and are considered safe when compared to beneficial gut lactobacilli. The research examined the intracellular bacteriostatic effects of recombinant L. acidophilus/AMPs on Gram-negative bacteria inside HEp-2 cells. Nevertheless, no notable bactericidal impact was seen on Gram-positive bacteria (P > 0.05). The research shows that recombinant L. acidophilus/AMPs, namely (L. acidophilus/melittin/Alyteserin-1a) as the focus of the investigation, effectively eliminate Gram-negative bacteria. Therefore, more investigation is necessary to elaborate on these discoveries.

Biopreservative and Anti-Mycotoxigenic Potentials of Lactobacillus paracasei MG847589 and Its Bacteriocin in Soft White Cheese

Probiotics and their bacteriocins have increasingly attracted interest for their use as safe food preservatives. This study aimed to produce soft white cheese fortified with Lacticaseibacillus MG847589 (Lb. paracasei MG847589) and/or its bacteriocin; cheese with Lacticaseibacillus (CP), cheese with bacteriocin (CB), and cheese with both Lacticaseibacillus and bacteriocin (CPB) were compared to control cheese (CS) to evaluate their biopreservative and anti-mycotoxigenic potentials for prolonged shelf life and safe food applications. The effects of these fortifications on physiochemical, microbial, texture, microstructure, and sensory properties were studied. Fortification with Lacticaseibacillus (CP) increased acidity (0.61%) and microbial counts, which may make the microstructure porous, while CPB showed intact microstructure. The CPB showed the highest hardness value (3988.03 g), while the lowest was observed with CB (2525.73 g). Consequently, the sensory assessment reflected the panelists' preference for CPB, which gained higher scores than the control (CS). Fortification with Lb. paracasei MG847589 and bacteriocin (CPB) showed inhibition effects against S. aureus from 6.52 log10 CFU/g at time zero to 2.10 log10 CFU/g at the end of storage, A. parasiticus (from 5.06 to 3.03 log10 CFU/g), and P. chrysogenum counts (from 5.11 to 2.86 log10 CFU/g). Additionally, CPB showed an anti-mycotoxigenic effect against aflatoxins AFB1 and AFM1, causing them to be decreased (69.63 ± 0.44% and 71.38 ± 0.75%, respectively). These potentials can extend shelf life and pave the way for more suggested food applications of safe food production by fortification with both Lb. paracasei MG847589 and its bacteriocin as biopreservatives and anti-mycotoxigenic.

Evaluating the roughness dynamics of kefir biofilms grown on Amazon cupuaçu juice: a monofractal and multifractal approach

We conducted a comprehensive analysis of the surface microtexture of kefir biofilms grown on Theobroma grandiflorum Shum (cupuaçu) juice using atomic force microscopy. Our goal was to investigate the unique monofractal and multifractal spatial patterns of these biofilms to complement the existing limited literature. The biofilms were prepared dispersing four different concentrations of kefir grains in cupuaçu juice. Our morphological analysis showed that the surface of the obtained biofilms is essentially formed by the presence of cupuaçu fibers and microorganisms like lactobacilli and yeast. The topographic height-based parameter analysis reveals that there is a dependence between surface roughness and the concentration of kefir grains used. The strongly anisotropic well-centralized topographical height distribution of the biofilms also exhibited a quasi-symmetrical and platykurtic pattern. The biofilms exhibit comparable levels of spatial complexity, surface percolation and surface homogeneity, which can be attributed to their similar topographic uniformity. This aspect was further supported by the presence of similar multifractality in the biofilms, suggesting that despite their varying topographic roughness, their vertical growth dynamics follow a similar pattern. Our findings demonstrate that the surface roughness of kefir biofilms cultivated on cupuaçu juice is influenced by the concentration of kefir grains in the precursor solution. However, this dependence follows a consistent pattern across different concentrations. Graphical Abstract.

Unraveling the mystery: a Mendelian randomized exploration of gut microbiota and different types of obesity

Background

Numerous studies have demonstrated the influence of gut microbiota on the development of obesity. In this study, we utilized Mendelian randomization (MR) analysis to investigate the gut microbiota characteristics among different types of obese patients, aiming to elucidate the underlying mechanisms and provide novel insights for obesity treatment.

Methods

Two-sample multivariable Mendelian randomization (MR) analysis was employed to assess causal relationships between gut microbiota and various obesity subtypes. Gut microbiota data were obtained from the international consortium MiBioGen, and data on obese individuals were sourced from the Finnish National Biobank FinnGen. Eligible single-nucleotide polymorphisms (SNPs) were selected as instrumental variables. Various analytical methods, including inverse variance weighted (IVW), MR-Egger regression, weighted median, MR-RAPS, and Lasso regression, were applied. Sensitivity analyses for quality control included MR-Egger intercept tests, Cochran's Q tests, and leave-one-out analyses and others.

Results

Mendelian randomization studies revealed distinct gut microbiota profiles among European populations with different obesity subtypes. Following multivariable MR analysis, we found that Ruminococcaceae UCG010 [Odds Ratio (OR): 0.842, 95% confidence interval (CI): 0.766-0.926, Adjusted P value: 0.028] independently reduced the risk of obesity induced by excessive calorie intake, while Butyricimonas [OR: 4.252, 95% CI: 2.177-8.307, Adjusted P value: 0.002] independently increased the risk of medication-induced obesity. For localized adiposity, Pasteurellaceae [OR: 0.213, 95% CI: 0.115-0.395, Adjusted P value: <0.001] acted as a protective factor. In the case of extreme obesity with alveolar hypoventilation, lactobacillus [OR: 0.724, 95% CI: 0.609-0.860, Adjusted P value: 0.035] reduced the risk of its occurrence. Additionally, six gut microbiota may have potential roles in the onset of different types of obesity. Specifically, the Ruminococcus torques group may increase the risk of its occurrence. Desulfovibrio and Catenabacterium may serve as protective factors in the onset of Drug-induced obesity. Oxalobacteraceae, Actinomycetaceae, and Ruminiclostridium 9, on the other hand, could potentially increase the risk of Drug-induced obesity. No evidence of heterogeneity or horizontal pleiotropy among SNPs was found in the above studies (all P values for Q test and MR-Egger intercept > 0.05).

Conclusion

Gut microbiota abundance is causally related to obesity, with distinct gut microbiota profiles observed among different obesity subtypes. Four bacterial species, including Ruminococcaceae UCG010, Butyricimonas, Pasteurellaceae and lactobacillus independently influence the development of various types of obesity. Probiotic and prebiotic supplementation may represent a novel approach in future obesity management.

Microbial screening of animal skin bags used in traditional cheesemaking

Bouhezza is a traditional Algerian cheese produced and ripened in goatskin bags called Djeld. The aim of this study was to characterize the microbial ecosystem from Djeld (fresh and dried Djeld for making Bouhezza cheese) and the changes introduced by Lben microflora during its preparation and to identify its role in cheesemaking and its safety. Two replicates of fresh and dried skin bags (FS and DS) were sampled and analyzed before and after contact with Lben. The microbiological results showed no pathogens. Skins observed before the addition of Lben were less populated 2.86 and 3.20 log CFU cm-2 than skins examined after the addition of Lben (approximately 6.0 log CFU cm-2), suggesting a potential role of Lben in releasing some microorganisms into the skin during its time in the Djeld. However, an increase in mesophilic lactic acid bacteria and yeasts was observed in Lben after different periods of interaction with the skin. PCR-TTGE revealed the predominance of lactic acid bacteria (Lactiplantibacillus plantarum, Limosilactobacillus fermentum, Staphylococcus equorum subsp. linens, Lactococcus cremoris, Streptococcus thermophilus) and a few high-GC-content bacteria (Lacticaseibacillus paracasei, Brevibacterium casei). Transfer of several microbial species was observed between the goatskin bag biofilm and Lben during the overnight interaction. Bands corresponding to Lacticaseibacillus paracasei, Brevibacterium casei, and Lactobacillus delbrueckii subsp. lactis were detected in the fresh skin profile and in Lben after contact with the fresh skin. Lacticaseibacillus paracasei was found in dried skin and Lben after contact with dry skin. Lactobacillus helveticus and Enterococcus faecalis appeared in the Lben profile and persisted in Lben and the biofilm-covered dry skin after interaction. These results demonstrate an exchange of specific microbial populations between goatskin bag biofilm and Lben during the traditional preparation method, suggesting that the diversity of goatskin biofilm contributes to the microbial diversity of Lben used in the production of Bouhezza cheese.

Revealing the formation mechanisms of key flavors in fermented broad bean paste

Pixian Douban (PXDB) is a popular Chinese condiment for its distinctive flavor. Broad bean fermentation (Meju) is the most important process in the formation of flavor substances. Key flavors were analyzed qualitatively and quantitatively, and metagenomic technology was applied to study the microbial diversity during broad bean fermentation. In addition, the main metabolic pathways of key flavors were explored. Results indicated that Staphylococcus_gallinarum was the main microorganism in the microbial community, accounting for 39.13%, followed by Lactobacillus_agilis, accounting for 13.76%. Aspergillus_flavus was the fungus with the highest species abundance, accounting for 3.02%. The KEGG Pathway enrichment analysis showed that carbohydrate metabolism and amino acid metabolism were the main metabolic pathways. Glycoside hydrolase and glycosyltransferase genes were the most abundant, accounting for more than 70% of the total number of active enzyme genes. A total of 113 enzymes related to key flavors and 39 microorganisms corresponding to enzymes were annotated. And Staphylococcus_gallinarum, Lactobacillus_agilis, Weissella_confusa, Pediococcus_acidilactici, Staphylococcus_kloosii, Aspergillus_oryzae, and Aspergillus_flavus played a key role in the metabolic pathway. This study reveals the formation mechanism of key flavors in fermented broad bean, it is important for guiding the industrial production of PXDB and improving product quality.

A metagenomic survey of bacterial communities from kurut: The fermented cow milk in Kyrgyzstan

Kurut is a traditional dry dairy product mostly consumed in Central Asia. In this study, the distribution of the dominant bacteria present in kurut samples (n=84) originated from seven (Chuy, Issyk-Kul, Talas, Naryn, Jalal-Abad, Osh, and Batken) regions in Kyrgyzstan were analyzed with Illumina iSeq100 platform. The dominant phylum detected was Firmicutes followed by Proteobacteria, Actinobacteria, Cyanobacteria/Chloroplast, and Tenericutes. The most abundant family detected was Lactobacillaceae followed by Streptococcaceae, Enterococcaceae, Chloroplast, and Leuconostocaceae. At the genus level, Lactobacillus was the predominant one in samples and Streptococcus, Enterococcus, Lactococcus, and Streptophyta followed this. Further comprehensive characterization analyses in kurut samples may have potential applications both in industrial starter culture developments and also future therapeutic approaches based on potential strains with probiotic properties.

Oral Postbiotics as a Therapeutic Strategy for Atopic Dermatitis: A Systematic Review of Randomized Controlled Trials

Atopic dermatitis (AD) is a prevalent chronic skin disease affecting all age groups. The connection with the gut microbiome led to oral probiotics as a therapeutic strategy. However, being viable microorganisms, probiotics might present risks. Thus, non-viable postbiotics have been considered as an alternative. We aimed to evaluate the efficacy of oral Lactobacillus postbiotics for managing symptoms of AD in pediatric and adult patients. A systematic review was conducted following PRISMA guidelines. Nine randomized controlled trials assessing the effects of non-viable Lactobacillus spp. administered orally to patients diagnosed with AD were included in the review, in which 512 subjects were evaluated after the intervention. Most studies allowed the concomitant usage of corticosteroids. Three studies focused on adults and indicated symptom improvement. In contrast, three out of six trials evaluating pediatric patients did not report postbiotics-favoring results. The dosage seems to be relevant for outcome determination. Two trials compared postbiotics with their viable analogs, and only one reported positive results in both groups. Postbiotics-associated shifts in gut microbial communities were reported in one trial. Mild adverse effects were detected by a single study. The overall results suggested that Lactobacillus postbiotics might be successfully used as adjuvant AD therapy in adults. Thus far, data do not indicate efficacy in pediatric patients. Standardizing nomenclatures and experimental procedures, as well as expanding the studies to more geographic locations and assessing comprehensively the effects on the gut microbiome would provide better perspectives of postbiotics as a therapeutic option for AD.

The use of Lentilactobacillus buchneri PJB1 and Lactiplantibacillus plantarum MTD1 on the ensiling of whole-plant corn silage, snaplage, and high-moisture corn

Experiments were conducted over a 3-yr period to evaluate the effects of bacterial inoculants on the fermentation profile and aerobic stability of whole-plant corn silage (WPC), snaplage (SNA), and high-moisture corn (HMC). Whole-plant corn was inoculated with Lentilactobacillus buchneri PJB1 in combination with Lactiplantibacillus plantarum MTD1 or with Lpb. plantarum alone (experiments 1 and 2). Snaplage (experiment 3) and HMC (experiments 4 and 5) were inoculated with Len. buchneri in combination with Lpb. plantarum or with Len. buchneri alone. After inoculation, the feedstuffs were ensiled in 7.57-L silos and stored at 21 ± 2°C for 30 or 90 d. In experiment 5, silage was subjected to air stress for 2 h every 2 wk through 42 d and then for 2 h/wk until 90 d and had samples analyzed for their bacterial community composition by metagenomics. Overall, in all experiments, silages inoculated with Len. buchneri alone or in combination with Lpb. plantarum had more acetic acid and 1,2-propanediol and fewer yeasts than uninoculated silages. After 30 d of ensiling, inoculation with Len. buchneri alone or in combination with Lpb. plantarum did not affect the aerobic stability of SNA, but it slightly increased the stability of WPC and markedly improved the stability of HMC. After 90 d of ensiling, inoculation with Len. buchneri alone or in combination with Lpb. plantarum markedly improved the aerobic stability of WPC, SNA, and HMC. In experiment 5, inoculation increased the relative abundance (RA) of Lactobacillaceae and reduced the RA of Enterobacteriaceae and Leuconostocaceae in HMC at 30 and 90 d and the RA of Clostridiaceae in non-air-stressed HMC at 90 d. Air-stressed HMC inoculated with Len. buchneri had less lactic acid, more acetic acid and 1,2-propanediol, and markedly greater aerobic stability than uninoculated air-stressed HMC at 90 d. In conclusion, inoculation with Len. buchneri PJB1 alone or in combination with Lpb. plantarum MTD1 increased the production of acetic acid and 1,2-propanediol, inhibited yeasts development, and improved the aerobic stability of WPC, SNA, and HMC. In HMC, inoculation markedly improved aerobic stability as soon as after 30 d of ensiling, and after 90 d, inoculation improved stability even under air stress conditions.

Lactobacillus juensis sp. nov. and Lactobacillus rizhaonensis sp. nov., isolated from the gut of honeybee (Apis mellifera)

Four lactic acid bacteria, designated F690T, F697, F790T and F769-2, were isolated from the gut of honeybee (Apis mellifera). Results of 16S rRNA gene sequence analysis indicated that strains F690T and F697 were phylogenetically related to the type strains of Lactobacillus kimbladii, Lactobacillus laiwuensis, Lactobacillus kullabergensis and Lactobacillus huangpiensis, having 99.1-99.6 % 16S rRNA gene sequence similarities; and that strains F790T and F769-2 were most closely related to the type strain of Lactobacillus melliventris, having 99.2-99.3 % 16S rRNA gene sequence similarities. The phylogenies based on concatenated pheS, rpoA, gyrB, hsp60, recA, rpoB and tuf sequences and based on whole genome sequences were identical to that based on 16S rRNA gene sequences. Strains F690T and F697 exhibited the highest average nucleotide identity (ANI; 92.1-93.2 %), digital DNA-DNA hybridization (dDDH; 50-50.1 %) and average amino acid identity (AAI; 94.9-95.1 %) values with L. kimbladii Hma2NT. Strains F790T and F769-2 had the highest ANI (93.1-94 %), dDDH (54.4 %) and AAI (94.4-94.7 %) values with L. melliventris Hma8NT. Based upon the data obtained in the present study, two novel species, Lactobacillus juensis sp. nov. and Lactobacillus rizhaonensis sp. nov., are proposed and the type strains are F690T (=JCM 36259T=CCTCC AB 2023131T) and F790T (=JCM 36260T=CCTCC AB 2023132T), respectively.

Strain specificity of lactobacilli with promoted colonization by galactooligosaccharides administration in protecting intestinal barriers during Salmonella infection

INTRODUCTION

Galactooligosaccharides (GOS) are lactogenic prebiotics that exert health benefits by stimulating the growth of different Lactobacillus strains in the gastrointestinal (GI) tract.

OBJECTIVES

This study aimed to investigate the mechanism of action of different GOS-enriched lactobacilli in intestinal health.

METHODS

Piglets and mice were supplemented with GOS to identify specific enrichment of Lactobacillus. The protective effects of individual GOS-enriched lactobacilli were investigated in Salmonella-infected mice. Macrophage depletion and transcriptome analysis were further performed to assess the involvement of macrophages and the underlying mechanisms of individual lactobacilli. An in vitro cell co-culture system was also used to evaluate the anti-adhesive and anti-invasive activities of lactobacilli against Salmonella in epithelial cells.

RESULTS

GOS markedly increased the relative abundance of three lactobacilli including L. delbrueckii, L. johnsonii, and L. reuteri in both piglets and mice. Supplementation with GOS further alleviated Salmonella infection in mice. L. delbrueckii (ATCC®BAA 365™), but not L. johnsonii or L. reuteri, enhanced propionate production in the intestinal tract and ameliorated Salmonella-induced intestinal inflammation and barrier dysfunction by suppressing the JAK2-STAT3 signaling and M1 macrophage polarization. L. johnsonii (BNCC 186110), on the other hand, inhibited Salmonella adhesion and invasion of epithelial cells through competitive exclusion. However, L. reuteri (BNCC 186135) failed to protect mice against Salmonella infection.

CONCLUSION

GOS-enriched lactobacilli show a differential role in protecting against Salmonella-induced intestinal barrier dysfunction and inflammation. Our results provide novel insights into the mechanism of action of GOS and individual Lactobacillus strains in the control and prevention of intestinal inflammatory disorders.

Prebiotic Activity of Pequi (Caryocar brasiliense Camb.) Shell on Lactobacillus and Bifidobacterium Strains: A Medicinal Food Ingredient

Pequi is a native and popular fruit in Cerrado biome. The internal yellow-orange mesocarp is the edible fraction of the fruit, but its shell (peel and external mesocarp), which comprises 80% of the fruit, is not used by the agro-industry during fruit processing. There is a growing interest in the reduction of food loss and waste because of environmental, economic, and social impacts. So this study evaluated the chemical composition, antioxidant capacity, and in vitro prebiotic activity of pequi shell flour. Pequi shell flour was obtained from the lyophilization and milling of pequi shell. The content of dietary fibers, oligosaccharides, sugars, organic acids, total phenolics and tannins, polyphenol profile, and antioxidant capacity was determined in pequi shell flour. In addition, its prebiotic activity was evaluated on growth and metabolism of probiotics Lactobacillus and Bifidobacterium strains. Pequi shell flour has a high content of dietary fibers (47.92 g/100 g), soluble fibers (18.65 g/100 g), raffinose (2.39 g/100 g), and phenolic compounds (14,062.40 mg gallic acid equivalents/100 g). For the first time, the polyphenols epigallocatechin gallate, epicatechin, and procyanidin B2 were identified in this by-product. Pequi shell flour promoted greater growth of Lacticaseibacillus casei L-26 (at 24-48 h) and Bifidobacterium animalis subsp. lactis BB-12, as well as higher prebiotic activity scores than fructooligosaccharides (standard prebiotic). Pequi shell flour is rich in prebiotic compounds and has a high antioxidant and prebiotic potential. The promising results encourage its use as an ingredient with antioxidant and potential prebiotic properties to elaborate new functional foods and nutraceuticals.

Relationship of Lactobacillus Vaginal Microbiota Changes and the Risk of Preterm Birth: A Systematic Review and Meta-Analysis

Objective: With a global incidence of more than 10%, preterm birth (PTB) remains a significant concern. The vaginal microbiome strongly influences the well-being of the female reproductive tract. This study examines the correlation between changes in Lactobacillus vaginal microbiota and the PTB risk. Materials and Methods: A thorough search of PubMed, Web of Science, Cochrane Library, and EMBASE was conducted to locate studies that examined the association between changes in Lactobacillus vaginal microbiota and the risk of PTB from January 1, 2010, to January 30, 2023. The risk of PTB was determined by calculating odds ratios (ORs) with 95% confidence intervals (CIs). Results: In our analysis, there were 11 studies with 1577 pregnant women. The findings revealed a significant negative correlation between higher Lactobacillus abundance and the PTB risk (OR = 0.49, 95% CI: 0.29-0.84, p = 0.009 < 0.05). Similarly, the four individual dominant species, Lactobacillus crispatus (OR = 0.3, 95% CI: 0.14-0.67, p = 0.003 < 0.05), Lactobacillus gasseri (OR = 0.34, 95% CI: 0.17-0.69, p = 0.003 < 0.05), Lactobacillus iners (OR = 0.68, 95% CI: 0.49-0.93, p = 0.016 < 0.05), and Lactobacillus jensenii (OR = 0.43, 95% CI: 0.21-0.89, p = 0.024 < 0.05), were also negatively associated with the PTB risk. The risk of Lactobacillus for PTB was significant in both America (OR = 0.67; 95% CI: 0.50-0.92) and Asia (OR = 0.20; 95% CI: 0.09-0.47), whereas no significant risk was found in Europe (OR = 0.49; 95% CI: 0.11-2.15). Conclusions: Our study demonstrated that the abundance of Lactobacillus and the four dominant individual species (L. crispatus, L. jensenii, L. iners, and L. gasseri) were significantly and negatively associated with the PTB risk.

Polyguluronate alleviates ulcerative colitis by targeting the gut commensal Lactobacillus murinus and its anti-inflammatory metabolites

Polyguluronate (PG) is a fermentable polysaccharide from edible algae. The present study was designed to investigate the therapeutic effect of PG on ulcerative colitis (UC) and its underlying mechanisms. Our results suggest that oral intake of PG attenuates UC and improves gut microbiota dysbiosis by promoting the growth of Lactobacillus spp. in dextran sulfate sodium-fed mice. Five different species of Lactobacillus were isolated from the feces of PG-treated mice and L. murinus was identified to have the best anti-colitis effect, suggesting a critical role for L. murinus in mediating the therapeutic effect of PG. Furthermore, PG was degraded potentially by the beta-glucuronidase from L. murinus and adding PG to the culture medium of L. murinus remarkably increased its production of anti-inflammatory metabolites, including itaconic acid, cis-11,14-eicosadienoic acid, and 3-amino-3-(2-chlorophenyl)-propionic acid. Additionally, L. salivarius, a human intestine-derived PG-utilizing species that is closely related to L. murinus, was also demonstrated to have potent anti-colitis effects, suggesting that it is a candidate target of PG in the human gut. Altogether, our study illustrates an unprecedented application of PG in the treatment of UC and establishes the basis for understanding its therapeutic effect from the perspective of L. murinus and its metabolites.

Ameliorative potential of synbiotic combination of Lactobacillus sp. and polyphenols against Benzo[a]pyrene-induced toxicity in Caco-2 cell line

Exposure to benzo[a]pyrene (B[a]P), a major global food safety concern, is often associated with increasing incidence of colorectal cancers. This in-vitro study was focused on the identification of potential B[a]P-adsorbing Lactobacillus strains and evaluation of the ameliorative effect of synbiotic combination of selected Lactobacillus sp. and polyphenols (quercetin or resveratrol) against B[a]P-induced intestinal toxicity in Caco-2 cells. Preliminary studies lead to the selection of Lactiplantibacillus plantarum MTCC 25433 strain that showed 86% of B[a]P adsorption in 2 h as compared to L. rhamnosus GG that showed 74% of B[a]P adsorption. B[a]P adsorption by MTCC 25433 was reduced to 9%, 16% and 20% upon pre-treatment with SDS, NaIO4 and mutanolysin, attributing the involvement of cell wall proteins and polysaccharides in the adsorption. Additionally, peptidoglycan of both strains adsorbed >50% of B[a]P. In-vitro assays revealed that the selected LAB mitigated the B[a]P-induced epithelial cell damage. Among the polyphenols, quercetin, resveratrol and curcumin, varied in their potency to mitigate B[a]P-induced oxidative stress, with curcumin being least effective. Combinations of selected Lactobacillus sp. and polyphenols were more potent in averting B[a]P-induced toxicity via increase in GSH (17-30 %), SOD (50-88 %), catalase (19-45 %), and reduction in IL-8 secretion (14-28 %) and barrier dysfunction. Principal component analysis affirmed the superior potency of combination of L. plantarum MTCC 25433 and quercetin in averting B[a]P-induced toxicity. Overall, this study highlighted a novel promising strategy of synbiotic combination of Lactobacillus sp. and polyphenols (quercetin or resveratrol) in alleviating the B[a]P-induced toxicity in intestinal epithelial cells.

Synbiotic Combination between Lactobacillus paracasei VL8 and Mannan-Oligosaccharide Repairs the Intestinal Barrier in the Dextran Sulfate Sodium-Induced Colitis Model by Regulating the Intestinal Stem Cell Niche

Previously, Lactobacillus paracasei VL8, a lactobacillus strain isolated from the traditional Finnish fermented dairy product Viili, demonstrated immunomodulatory and antibacterial effects. The prebiotic mannan-oligosaccharide (MOS) further promoted its antibacterial activity and growth performance, holding promise for maintaining intestinal health. However, this has not been verified in vivo. In this study, we elucidated the process by which L. paracasei VL8 and its synbiotc combination (SYN) with MOS repair the intestinal barrier function in dextran sodium sulfate (DSS)-induced colitis mice. SYN surpasses VL8 or MOS alone in restoring goblet cells and improving the tight junction structure. Omics analysis on gut microbiota reveals SYN's ability to restore Lactobacillus spp. abundance and promote tryptophan metabolism. SYN intervention also inhibits the DSS-induced hyperactivation of the Wnt/β-catenin pathway. Tryptophan metabolites from Lactobacillus induce intestinal organoid differentiation. Co-housing experiments confirm microbiota transferability, replicating intestinal barrier repair. In conclusion, our study highlights the potential therapeutic efficacy of the synbiotic combination of Lactobacillus paracasei VL8 and MOS in restoring the damaged intestinal barrier and offers new insights into the complex crosstalk between the gut microbiota and intestinal stem cells.

Lactobacillus reuteri inhibits Staphylococcus aureus-induced mastitis by regulating oxytocin releasing and gut microbiota in mice

Mastitis is the most frequent disease of cows and has well-recognized detrimental effects on animal wellbeing and dairy farm profitability. With the advent of the postantibiotic era, alternative antibiotic agents, especially probiotics, have received increasing attention in the treatment of mastitis. Based on research showing that Lactobacillus reuteri (L. reuteri) has anti-inflammatory effects, this study explored the protective effects and mechanisms of L. reuteri against mastitis induced by Staphylococcus aureus (S. aureus) in mice. First, mice with S. aureus-induced mastitis were orally administered L. reuteri, and the inflammatory response in the mammary gland was observed. The results showed that L. reuteri significantly inhibited S. aureus-induced mastitis. Moreover, the concentration of oxytocin (OT) and protein expression of oxytocin receptor (OTR) were measured, and inhibition of OTR or vagotomy reversed the protective effect of L. reuteri or its culture supernatant (LCS) on S. aureus-induced mastitis. In addition, in mouse mammary epithelial cells (MMECs), OT inhibited the inflammation induced by S. aureus by inhibiting the protein expression of OTR. It was suggested that L. reuteri protected against S. aureus-induced mastitis by releasing OT. Furthermore, microbiological analysis showed that the composition of the microbiota was altered, and the relative abundance of Lactobacillus was significantly increased in gut and mammary gland after treatment with L. reuteri or LCS. In conclusion, our study found the L. reuteri inhibited the mastitis-induced by S. aureus via promoting the release of OT, and treatment with L. reuteri increased the abundance of Lactobacillus in both gut and mammary gland.

Parental Social Isolation during Adolescence Alters Gut Microbiome in Rat Male Offspring

Previous work from our laboratory demonstrated that parental stress, induced by social isolation starting at puberty, leads to behavioral, endocrine, and biochemical changes in the male, but not female, offspring (ISO-O) of Sprague-Dawley rats. Here, we report alterations in the gut microbiota composition of ISO-O vs. grouped-housed offspring (GH-O), although all animals received the same diet and were housed in the same conditions. Analysis of bacterial communities by next-generation sequencing (NGS) of 16S rRNA gene revealed alterations at family and order levels within the main phyla of Bacteroides, Proteobacteria, and Firmicutes, including an almost total deficit in Limosilactobacillus reuteri (formerly Lactobacillus reuteri) and a significant increase in Ligilactobacillus murinus (formerly Lactobacillus murinus). In addition, we found an increase in the relative abundance of Rhodospirillales and Clostridiales in the families of Lachnospiraceae and Ruminococcaceae, and Bacteroidales in the family of Prevotellaceae. Furthermore, we examined plasma levels of the proinflammatory cytokines interleukin-1-beta and tumor necrosis factor-alpha, which did not differ between the two groups, while corticosterone concentrations were significantly increased in ISO-O rats. Our findings suggest that adverse environmental conditions experienced by parents may have an impact on the likelihood of disease development in the subsequent generations.

Companilactobacillus alimentarius: An extensive characterization of strains isolated from spontaneous fermented sausages

Companilactobacillus alimentarius is a facultatively heterofermentative lactic acid bacterium (LAB) that is a significant constituent within the microbiota of various traditional fermented foods exerting several functions in fermentative or ripening processes. This species has been isolated from Spanish fermented sausages, where its frequency of isolation was comparable to those of Latilactobacillus sakei and Latilactobacillus curvatus. Despite to its presence in several niches, ecological information on this species is still scarce and only few publications report information about its safety features (i.e. antibiotic resistance). Since studies on C. alimentarius concern the analysis of a few individual traits regarding this species, a more extensive work on a larger number of isolates from the same matrix have been performed to allow a clearer interpretation of their phenotypic and technological characteristics. Specifically, 14 strains of C. alimentarius isolated from Mediterranean spontaneously fermented sausages, have been screened for their safety and technological characteristics (such as antibiotic resistance, biogenic amine production, inhibiting potential, growth at different temperatures and NaCl concentrations) and with phenotype microarrays with the aim to elucidate their potential role and contribution to sausage fermentation and ripening. In general, a wide variability was observed in relation to the parameters considered. Several of the tested strains were able to produce histamine, tyramine and putrescine while the antibiotic resistance greatly varied according to the strains, with the exception of vancomycin. In addition, C. alimentarius strains showed a relevant potential to grow in conditions of salt and temperature mimicking those found in fermented foods. In particular, the growth at 10 °C and in the presence of salt can explain the presence of C. alimentarius in sausages and its adaptation to fermented meat environment in which low temperature can be applied during ripening. The differentiation of the phenotypic profile reflected the environmental conditions that influenced the isolation source, including those derived by the raw materials. Given the species frequent association with spontaneous fermentations or the ripening microbiota of various products, despite not being intentionally used as starter cultures, the data presented in this study contribute to a deeper comprehension of their role, both advantageous and detrimental, in numerous significant fermented foods.

Evaluation of the Efficacy of a Lactobacilli-Based Teat Detergents for the Microbiota of Cows Teats Using an Untargeted Metabolomics Approach

Teat cleaning pre- and post-milking is important for the overall health and hygiene of dairy cows. The purpose of this research was to evaluate the effectiveness of a teat detergents based on lactic acid bacteria according to changes in somatic cell count and cow-milk metabolites. Sixty-nine raw milk samples were collected from 11 Holstein-Friesian cows in China during 12 days of teat cleaning. An ultra-performance liquid chromatography-quadrupole-time of flight mass spectrometry-based untargeted metabolomic approach was applied to detect metabolomic differences after treatment with lactic acid bacteria and chemical teat detergents in cows with subclinical mastitis. The results suggest that the lactobacilli-based teat detergents could reduce somatic cell count and improve microhabitat of cow teat apex by adjusting the composition of metabolites. Furthermore, the somatic cell count could be decreased significantly within 10 days following the cleaning protocol. Lactic acid bacteria have the potential to be applied as a substitution to teat chemical detergents before and after milking for maintenance of healthy teats and breasts. Further, larger scale validation work is required to support the findings of the current study.

A combined effect of fish-originated collagen peptides and caffeine on the cognitive function of sleep-deprived mice

Refreshing beverages, consumed worldwide, commonly take advantage of caffeine's impacts on attention and motor performance. However, excessive long-term caffeine intake might disturb sleep/wake rhythms and exacerbate daily anxiety. Fish-originated collagen peptides (FCP) are of high nutrient value with stimulating, calming or relaxing effects, which could reduce the excitotoxicity of caffeine. This study aims to investigate two facets: (1) the combined effect of caffeine and FCP (namely C&F) on the cognitive function of sleep-deprived mice by different administration strategies with dose dependence (low and high dose) or time dependence (intervention in a day and prevention for a week); (2) the potential "microbiota-gut-brain" mechanism by which C&F improves sleep deprivation (SD)-induced cognitive impairments. Here, C57BL/6 mice were administered caffeine (10 or 20 mg per kg per bw) combined with FCP (100 or 200 mg per kg per bw) and were then subjected to 48 h SD. The open-field and Morris water maze tests were performed to evaluate the cognitive function and spatial learning capacities of mice. Our results indicated that the cognitive impairments of SD mice were significantly relieved to a different degree by treating C&F in a dose- and time-dependent manner. The pathological observation of the hippocampus indicated both intervention (time of a day) and prevention (time of a week) of the C&F protected brain tissue from SD-induced injuries. The accumulated pro-inflammatory neurometabolites and factors were significantly inhibited by C&F via the hypothalamus-hippocampal circuit. Furthermore, 16S rDNA analysis of colonic contents showed that the level of Lactobacillus murinus was significantly upregulated and that of Clostridia_UCG-014 was suppressed in the C&F group. The receiver operating characteristic (ROC) curve of Lactobacillus murinus indicated a certain diagnostic utility to distinguish C&F intervention (AUC = 0.52) or prevention (AUC = 0.68). Pathways of ko04622 (immune system) and ko00472 (metabolism processes) were significantly regulated by C&F in a time-dependent manner. Based on PICRUSt2 algorithm analysis, C&F might potentially regulate gut microbial functions through several metabolic pathways, including the RIG-I-like receptor signaling pathway and limonene and pinene degradation. In conclusion, C&F plays a key role in brain function and behavior, which could synergistically relieve cognitive impairments via the microbiota-gut-brain axis.

Analysis of the Influence of Lactiplantibacillus plantarum and Lacticaseibacillus rhamnosus Strains on Changes in the Hexachlorobenzene Content in Fermented Mare Milk during Refrigerated Storage

(1) Background: Hexachlorobenzene (HCB) is a persistent organic pollutant that is possibly carcinogenic to humans. It is still found in the environment, humans and animals, and in foods, including milk and dairy products; (2) Methods: The influence of the probiotic cultures Lacticaseibacillus rhamnosus LCR and Lactiplantibacillus plantarum subsp. plantarum LP on the possibility of effecting the biodegradation of HCB in dairy products fermented from mare milk was investigated, taking into account the product storage time (maximum 21 days). HCB content was determined using the GC/MS method; (3) Results: A strong negative Pearson correlation (p < 0.05) was found between HCB concentration and the refrigeration storage time of the fermented beverages. The highest HCB reduction was observed in milk fermented with both Lacticaseibacillus rhamnosus LCR and Lactiplantibacillus plantarum subsp. plantarum LP (78.77%), while the lowest was noted when only Lactiplantibacillus plantarum subsp. plantarum LP was used (73.79%); (4) Conclusions: This pilot study confirmed that probiotics commonly used to give products health-promoting properties can also contribute to reducing the content of undesirable substances, and the bacterial cultures used might provide an alternative method for reducing HCB residues in fermented drinks.

Soft rot of postharvest pepper: bacterial pathogen, pathogenicity and its biological control using Lactobacillus farciminis LJLAB1

BACKGROUND

Soft rot is the most important bacterial disease of postharvest pepper during storage and transportation. The main objectives of this study were to investigate the bacterial pathogen species causing pepper soft rot and seek for an antagonistic bacterium to control this disease.

RESULTS

Pathogens Pectobacterium carotovorum, Enterobacter sp., Klebsiella sp., Pseudomonas sp. and Bacillus sp. were verified to be the causes of soft rot which were isolated from rotten peppers. Among them, P. carotovorum had the highest prevalence, including P. carotovorum subsp. carotovorum (Pcc) and P. carotovorum subsp. brasilisesis (Pcb). The result of pathogenicity analysis showed that Pcb Jm2 had strong pathogenicity at 25 °C even at a cell concentration of 103  CFU mL-1 . Its pathogenicity decreased at 4 °C. Multiple pathogenic factors were identified in the draft genome of Pcb Jm2, including cellulase, pectinase, pectin methylesterase, pectinesterase, pectin lyase, polygalacturonase and so forth. Further, the disease control ability of Lactobacillus farciminis LJLAB1 was investigated. The cell-free supernatant (CFS) and crude bacteriocin of L. farciminis LJLAB1 had good antibacterial activities to Pcb Jm2 in vitro, but CFS exhibited a better disease control effect in vivo. CFS treatment prevented the damage of pepper epidermal structure caused by Pcb Jm2, and 99.26% of pathogen cells on pepper were killed by it. Moreover, CFS treatment delayed firmness decrease, soluble solid content loss, weight loss, yellowing and malonaldehyde accumulation of pepper during storage after pathogen infection.

CONCLUSION

L. farciminis LJLAB1 can be an effective biological control agent to control pepper soft rot caused by Pcb. © 2023 Society of Chemical Industry.

Modulation of Broiler Intestinal Changes Induced by Clostridium perfringens and Deoxynivalenol through Probiotic, Paraprobiotic, and Postbiotic Supplementation

Deoxynivalenol (DON) is a predisposing factor for necrotic enteritis. This study aimed to investigate the effects of a DON and Clostridium perfringens (CP) challenge on the intestinal morphology, morphometry, oxidative stress, and immune response of broilers. Additionally, we evaluated the potential of a Lactobacillus spp. mixture as an approach to mitigate the damage induced by the challenge. One-day-old broiler chickens (n = 252) were divided into seven treatment groups: Control, DON, CP, CP + DON, VL (DON + CP + viable Lactobacillus spp. mixture), HIL (DON + CP + heat-inactivated Lactobacillus spp. mixture), and LCS (DON + CP + Lactobacillus spp. mixture culture supernatant). Macroscopic evaluation of the intestines revealed that the CP + DON group exhibited the highest lesion score, while the VL and HIL groups showed the lowest scores. Microscopically, all Lactobacillus spp. treatments mitigated the morphological changes induced by the challenge. DON increased levels of reactive oxygen species (ROS) in the jejunum, and CP increased ROS levels in the jejunum and ileum. Notably, the Lactobacillus spp. treatments did not improve the antioxidant defense against CP-induced oxidative stress. In summary, a Lactobacillus spp. mixture, whether used as a probiotic, paraprobiotic, or postbiotic, exerted a partially protective effect in mitigating most of the intestinal damage induced by DON and CP challenges.

The effect and mechanism of Fushen Granule on gut microbiome in the prevention and treatment of chronic renal failure

Background

Fushen Granule is an improved granule based on the classic formula Fushen Formula, which is used for the treatment of peritoneal dialysis-related intestinal dysfunction in patients with end-stage renal disease. However, the effect and mechanism of this granule on the prevention and treatment of chronic renal failure have not been fully elucidated.

Methods

A 5/6 nephrectomy model of CRF was induced and Fushen Granule was administered at low and high doses to observe its effects on renal function, D-lactate, serum endotoxin, and intestinal-derived metabolic toxins. The 16SrRNA sequencing method was used to analyze the abundance and structure of the intestinal flora of CRF rats. A FMT assay was also used to evaluate the effects of transplantation of Fushen Granule fecal bacteria on renal-related functional parameters and metabolic toxins in CRF rats.

Results

Gavage administration of Fushen Granule at low and high doses down-regulated creatinine, urea nitrogen, 24-h urine microalbumin, D-lactate, endotoxin, and the intestinal-derived toxins indophenol sulphateand p-cresol sulphate in CRF rats. Compared with the sham-operated group in the same period, CRF rats had a decreased abundance of the firmicutes phylum and an increased abundance of the bacteroidetes phylum at the phylum level, and a decreasing trend of the lactobacillus genus at the genus level. Fushen Granule intervention increased the abundance of the firmicutes phylum, decreased the abundance of the bacteroidetes phylum, and increased the abundance of the lactobacillus genus. The transplantation of Fushen Granule fecal bacteria significantly reduced creatinine(Cr), blood urea nitrogen(Bun), uric acid(UA), 24-h urinary microalbumin, D-lactate, serum endotoxin, and enterogenic metabolic toxins in CRF rats. Compared with the sham-operated group, the transplantation of Fushen Granule fecal bacteria modulated the Firmicutes and Bacteroidetes phyla and the Lactobacillus genus.

Conclusion

Fushen Granule improved renal function and intestinal barrier function by regulating intestinal flora, inhibiting renal fibrosis, and delaying the progression of chronic renal failure.