Probiotic Bacteria Lactobacillus Research Articles

Next-Generation Sequencing to Determine Changes in the Intestinal Microbiome of Juvenile Sturgeon Hybrid (Acipenser gueldenstaedtii♀ × Acipenser baerii♂) Resulting from Sodium Butyrate, Β-Glucan and Vitamin Supplementation

Background/Objectives: The effect of sodium butyrate (NaB), β-glucan (βG) and vitamins in the diet on gut microbiome, cortisol level, lysozyme activity and growth parameters of juvenile hybrid sturgeon (Acipenser gueldenstaedtii♀ × Acipenser baerii♂) was determined. Methods: Sturgeon hybrids (n = 144) were divided into three groups with enriched feeding (mg/kg of feed): FQV1 (50 NaB; 20 βG; const. vitamins), FQV2 (150 NaB; 20 βG; const. vitamins), FQV3 (50 NaB; 60 βG; const. vitamins) and control (not supplemented), each group in triplicate, 12 fish in each repetition. Rearing was carried out for 30 days in controlled conditions. Gut microbiome was characterized using Next Generation Sequencing (NGS) of DNA samples isolated from intestinal content. Cortisol level was determined using the ELISA test. Lysozyme activity was measured by turbidimetric test. Results: Based on data obtained from NGS, it was determined that the FQV1 group is characterized by the highest values of diversity indices (Shannon, Simpson and Chao-1) and the largest number of ASVs (Amplicon Sequence Variants). The highest abundance of probiotic bacteria (Lactobacillus, Lactococcus) was determined in the FQV1 group. The highest cortisol concentration was determined in the control (33.26 ng/mL), while the lowest was in FQV3 (27.75 ng/mL). The highest lysozyme activity was observed in FQV1 (154.64 U/mL), and the lowest in FQV2 (104.39 U/mL) and control (121.37 U/mL) (p < 0.05). FQV2 was characterized by significantly more favorable values of breeding indicators (p < 0.05). Conclusions: The obtained results prove that an appropriate composition of NaB, βG and vitamins can be used in the commercial breeding of juvenile hybrid sturgeons.

β-galactosidase producing Lactiplantibacillus spp in intestinal microbiome mouse diarrhea model and metagenomic analyses

Probiotics have attained significant interest in recent years as a result of their gut microbiome modulation and gastrointestinal health benefits. Numerous fermented foods contain LAB with GRAS grade and probiotic bacteria. The most promising isolates with high potentiality were selected for 16S rRNA gene sequence analysis and identified as Lactiplantibacillus plantarum, L. fermentum, L. pentosus and Lactiplantibacillus sp. The present study was conducted to determine the gastrointestinal symptoms after the consumption of milk and dairy products, lactose intolerance status using mice model. Post-weaning Balb/c mice were orally administered with probiotic bacteria to assess their efficiency in reducing lactose intolerance symptoms. They exhibited significantly reduced total feces weight and slower intestinal motility and they efficiently alleviated diarrhea symptoms within 6 h of lactose challenge in lactose intolerance-induced mice. Next generation sequence analysis was performed using intestinal content of model treated with L. plantarum GV54 and GV64, the intestinal bacterial diversity was studied using Illumina NGS analysis (16S rRNA hypervariable regions [V3 and V4]). NGS report confirmed the existence of the dominant phyla of the gut microbiome in mice are Bacteroidetes, Firmicutes and Proteobacteria. Due to the influence of the probiotic bacteria in the model group (GV54 and GV64), maximum abundance of phylum Firmicutes were observed when compared to the control group, whereas control group showed more abundance of phylum Bacteriodetes. However, the relative abundance of Bacteroidetes in the model group was decreased and Firmicutes abundance was increased. This indicates the genus abundance of Lactobacillus (Lactiplantibacillus) species or Lactiplantibacillus plantarum GV54 and GV64 bacteria. After treatment with probiotic bacteria Lactobacillus (Lactiplantibacillus) species, the probiotic bacterial abundance was increased consequently genera Helicobacter, Clostridiales unclassified and Desulfovibrio were decreased in the model groups. Probiotic bacteria has a positive impact on the regulation of intestinal microbial diversity in the tested mice system and it reflects that the intestinal microbiota of mice is dynamic and has positive impact on gut health. Considering this point, it is possible to promote Lactiplantibacillus spp. as probiotics and therapeutic food development at industrial scale.

Co-encapsulation of probiotic bacteria L. rhamnosus GG and β-carotene by a novel biphasic encapsulation technique: Stability and in vivo anti-inflammatory properties

In this study, β-carotene (βC) was encapsulated in liposomes and spray-dried with the probiotic bacteria Lactobacillus rhamnosus GG (LGG), to obtain a biphasic structure with two functional components. Initially, the liposomes loaded with βC resulted in large multivesicular vesicles (LMVV) with spherical morphology, mean size of 1191 nm and entrapment efficiency of 81.33%. Then, the spray-drying of the mixture βC-LMVV with the LGG resulted in biphasic dried microparticles (BDM) with a spherical shape, retention of 64,48% of βC, and LGG survivor above 90%. The BDM showed high storage stability for 90 days at room temperature and, at the dose of 2000 mg/kg of BDM did not cause any acute toxicity in Wistar rats. In addition, at the same dose, presented significant anti-inflammatory activity in carrageenan-induced paw edema and pleurisy. Thus, the produced BDM could be an innovative ingredient with functional properties and also an efficient encapsulation strategy for βC.

Prebiotic potential of melon (Cucumis melo L.) and watermelon (Citrullus lanatus) shell flours

A potential alternative way of using agricultural waste such as melon and watermelon shells is its use as a prebiotic ingredient, which may improve the production of beneficial metabolites during microbial fermentation in the intestinal section of the host, through probiotic bacteria. The objective of this study wasto evaluate the prebiotic potential of melon and watermelon, which were subjected to an in vitro digestion process and subsequently analyzed by scanning electron microscope. The digest was used as a source of carbohydrates during fermentation by 3 probiotic bacteria (Lactobacillus brevis, L. paracasei, and L. rhamnosus) at 24 and 48 h, evaluating bacterial growth, carbohydrate consumption and the production of short-chain fatty acids (acetic, propionic and butyric acids). Results indicated a degradation of melon and watermelon shells after the digestion process, likewise, the growth of lactic acid bacteria was observed using melon and watermelon shells as a source of carbohydrates.These compounds were significantly reduced at 24 and 48 h. Finally, at 48 h, a higher content of short-chain fatty acids was present with a concentration of 922.31 μmol/L of acetic acid with L. brevis and melon shell, 27.6 μmol/L of propionic acid with L. rhamnosus and melon shell, and 4.96 x10−13 μmol/L of butyric acid with L. rhamnosus with melon and watermelon shells, which suggests that these types of shells have prebiotic potential.

Probiotic bacteria protect against indomethacin-induced gastric ulcers through modulation of oxidative stress, inflammation, and apoptosis.

Indomethacin is an anti-inflammatory drug that causes ulcers on the gastric mucosa due to its use. Probiotic bacteria are live microorganisms, and it has been stated by various studies that these bacteria have antioxidant and anti-inflammatory effects. In this study, we investigated the possible protective effect of various types of probiotic bacteria (Lactobacillus rhamnosus, Lactobacillus fermentum, and Lactobacillus brevis) against acute gastric mucosal damage caused by indomethacin. Control group - Physiological saline was administered daily for 10 days. Indo group-Physiological saline was administered daily for 10 days. Ranitidine + Indo group 5mg/kg ranitidine dose was administered daily for 5 days. On day 11, a single dose of 100mg/kg of indomethacin was given to the same group. Probiotic + Indo group 1ml/kg of oral probiotic bacteria was administered daily for 10 days. On day 11, a single 100mg/kg dose of indomethacin was given. After the application, the rats were anesthetized with ketamine xylazine, killed under appropriate conditions, the abdominal cavity was opened and the stomach tissues were removed. The obtained gastric tissues were used in the biochemical and histopathological analyses discussed below. All data were statistically evaluated by one-way ANOVA using SPSS 20.00, followed by Duncan Post hoc test. The data were expressed as mean ± SD. P < 0.05 was considered statistically significant. As a result, the administration of indomethacin caused gastric damage, stimulating oxidative stress, inflammation, and apoptosis. We found that the use of probiotic bacteria reduces oxidative stress (TOC), increases the activity of antioxidant enzymes (TAC), suppresses inflammation (IL-6 and Tnf-α), and inhibits apoptosis (Bax and Bcl-2) (P < 0.05). Probiotic treatment can mitigate gastric damage and apoptosis caused by indomethacin-induced gastric damage in rats. Probiotic also enhances the restoration of biochemical oxidative enzymes as it has anti-inflammatory, antioxidant, and antiapoptotic properties.

Antimicrobial Properties of Flavonoid Derivatives with Bromine, Chlorine, and Nitro Group Obtained by Chemical Synthesis and Biotransformation Studies.

The search for new substances of natural origin, such as flavonoids, is necessary in the fight against the growing number of diseases and bacterial resistance to antibiotics. In our research, we wanted to check the influence of flavonoids with chlorine or bromine atoms and a nitro group on pathogenic and probiotic bacteria. We synthesized flavonoids using Claisen-Schmidt condensation and its modifications, and through biotransformation via entomopathogenic filamentous fungi, we obtained their glycoside derivatives. Biotransformation yielded two new flavonoid glycosides: 8-amino-6-chloroflavone 4'-O-β-D-(4″-O-methyl)-glucopyranoside and 6-bromo-8-nitroflavone 4'-O-β-D-(4″-O-methyl)-glucopyranoside. Subsequently, we checked the antimicrobial properties of the aforementioned aglycon flavonoid compounds against pathogenic and probiotic bacteria and yeast. Our studies revealed that flavones have superior inhibitory effects compared to chalcones and flavanones. Notably, 6-chloro-8-nitroflavone showed potent inhibitory activity against pathogenic bacteria. Conversely, flavanones 6-chloro-8-nitroflavanone and 6-bromo-8-nitroflavanone stimulated the growth of probiotic bacteria (Lactobacillus acidophilus and Pediococcus pentosaceus). Our research has shown that the presence of chlorine, bromine, and nitro groups has a significant effect on their antimicrobial properties.

Pearl millet flour and green gram milk based probiotic beverage

The probiotic beverage was developed using germinated and ungerminated pearl millet flour and green gram milk. The germinated and ungerminated pearl millet flour was added to green gram milk at different concentrations (0.5–2.5 %) along with sugar and cardamom. The mixtures were then inoculated with probiotic bacteria Lactobacillus acidophilus incubated at 37 °C for 6 h. Characterization of probiotic beverages was carried out during storage at (4 ± 1)°C for 21 days. The germinated flour beverage had high acidity as compared to the ungerminated flour beverage. The probiotic count in germinated and ungerminated flour beverages ranged from 8.19 to 8.77 × 107 and 8.04 to 8.52 × 107 log CFU/mL, respectively. Antioxidant activity, polyphenol content increased with an increase in the concentration of flour in the beverage. The LC-MS analysis found the existence of vitexin and isovitexin as the main polyphenolic compounds in the probiotic beverage. Non-dairy probiotic beverage prepared with 0.5 % germinated millet flour gave the best taste, color, texture, and rheological properties.

The Probiotic Lactobacillus reuteri Preferentially Synthesizes Kynurenic Acid from Kynurenine.

The gut-brain axis is increasingly understood to play a role in neuropsychiatric disorders. The probiotic bacterium Lactobacillus (L.) reuteri and products of tryptophan degradation, specifically the neuroactive kynurenine pathway (KP) metabolite kynurenic acid (KYNA), have received special attention in this context. We, therefore, assessed relevant features of KP metabolism, namely, the cellular uptake of the pivotal metabolite kynurenine and its conversion to its primary products KYNA, 3-hydroxykynurenine and anthranilic acid in L. reuteri by incubating the bacteria in Hank's Balanced Salt solution in vitro. Kynurenine readily entered the bacterial cells and was preferentially converted to KYNA, which was promptly released into the extracellular milieu. De novo production of KYNA increased linearly with increasing concentrations of kynurenine (up to 1 mM) and bacteria (107 to 109 CFU/mL) and with incubation time (1-3 h). KYNA neosynthesis was blocked by two selective inhibitors of mammalian kynurenine aminotransferase II (PF-048559989 and BFF-122). In contrast to mammals, however, kynurenine uptake was not influenced by other substrates of the mammalian large neutral amino acid transporter, and KYNA production was not affected by the presumed competitive enzyme substrates (glutamine and α-aminoadipate). Taken together, these results reveal substantive qualitative differences between bacterial and mammalian KP metabolism.

Impact of the gut–brain axis on neurodegenerative diseases and potential benefits of probiotics

Gut microbiota are an essential community for human health. They produce different bioactive components and short-chain fatty acids for physiological benefits. Intestinal flora elicits an immune response and maintains a balance between inflammatory and anti-inflammatory cytokines during the inflammatory response. The intricate relationship between the activities of gut microbes and brain functions creates the gut–brain axis. Microbial metabolites of the gut reach the brain through blood and lymphatic circulation. The bioactive components from gut microorganisms regulate oxidative stress, cytokine profiles, neuroinflammation, apoptotic reactions and neurodegeneration. Dysbiosis alters the activity of gut microbiota, which causes gastrointestinal disorders, neurodegenerative diseases, metabolic syndrome and cancers. Probiotic bacteria (Lactobacillus spp., Bifidobacterium spp.) have different health promotional effects and exhibit a significant role in immunomodulation. These bacteria display some protective role against various diseases, including neurodegenerative disorders.

Survival of Encapsulated Vs. Free Probiotics in Fruit Juices During Refrigerated Storage and In Vitro Gastrointestinal Digestion

This study investigated the viability and resilience of free and encapsulated probiotic bacteria (Lactobacillus plantarum and Lactobacillus casei) in commercial apple and tomato juices during refrigerated storage and simulated gastrointestinal digestion.

Dietary Probiotic Supplementation on Hematological and Immunological Parameters of Indian Major Carp (Labeo rohita)

A 60-day feeding trial was conducted to evaluate the influence of dietary supplementation of probiotic bacteria (Lactobacillus acidophilus) to improve the hematological and immunological parameters of Indian Major carp Rohu (Labeo rohita). The rohu Fingerlings (mean body weight 6.0±0.6g) were randomly distributed into Four treatment groups each having 10 fishes fed with basal diet and a probiotic supplement containing L. acidophilus (1.0×107 CFU/g), then challenged with A. hydrophila (0.1 × 107 CFU/mL) was injected intraperitoneally with 0.1ml concentration of 107 CFU/ml on 55th day. After 72 hours, the blood samples were collected from five fish from each group. The hematological parameters such as hemoglobin (Hb; g/dL), red blood cell (RBC; ×106/mm3), white blood cell (WBC; ×103/mm3), and Packed corpuscular volume (PCV) along with immunological parameters of total immunoglobulin, serum lysozyme activity, and Aminotransferases were examined and compared with the control group. The fish fed with probiotics showed significant improvement in hematological and Immunological Parameters (P≤0.05) as compared to control. This study proved that probiotic bacteria L. acidophilus are resistant to pathogenic A. hydrophila and can contribute to improving the immune system, survival rate, and growth of experimental fish against the fish pathogen A. hydrophila.

Physicochemical, microbial, and sensory characteristics of yogurt with Persian shallot (Allium hirtifolium Boiss) and probiotic bacteria.

The aim of this study was to investigate the characteristics of yogurt prepared with the addition of Persian shallot and probiotic bacteria. The effect of Persian shallot on the viability of probiotic bacteria (Lactobacillus acidophilus and Bifidobacterium bifidum) was evaluated. Furthermore, the antimicrobial effects of shallot and probiotic bacteria on Listeria monocytogenes and Escherichia coli species were investigated. The experiments were performed on days 0, 1, 7, 14, and 21. The results showed that the survival of lactic acid bacteria increased significantly in the presence of shallots (p < .05). The addition of two different probiotic bacteria to the yogurt samples inhibited the pathogenic bacteria. While E. coli bacteria had a 3-log reduction, L. monocytogenes did not grow at all in the presence of probiotic bacteria and shallots. Based on these experiments, it was concluded that the addition of shallots not only increased the survival of probiotic bacteria but also reduced the growth of food-borne pathogenic bacteria. In addition, the addition of probiotic bacteria increased the acceptance of sensory properties of yogurt samples.

Influence of supplementation with iron and probiotic bacteria Lactobacillus plantarum and Lactobacillus curvatus on selected parameters of inflammatory state in rats on a high-fat iron-deficient diet.

A high-fat (HF) diet, diet iron deficiency and iron supplementation may affect inflammatory parameters. Probiotics influence both iron metabolism and inflammation. We compared the inflammatory state in rats on a HF iron-deficient diet receiving oral iron, Lactobacillus plantarum and Lactobacillus curvatus in different combinations. This was a two-stage experiment. In groups C (n = 8) and HF (n = 8), rats ate a control or HF diet, respectively, for 16 weeks. In the group HFDEF (n = 48), rats ate a HF iron-deficient diet for 8 weeks (first stage) and were subsequently divided into 6 groups (n = 8 each) receiving the following for a further 8 weeks (second stage): HFDEF - a HF iron-deficient diet; HFDEFFe - a HF iron-deficient diet with iron; HFDEFLp and HFDEFLc - a HF iron-deficient diet with L. plantarum or L. curvatus, respectively; and HFDEFFeLp and HFDEFFeLc - a HF iron-deficient diet with iron and L. plantarum or L. curvatus, respectively. Body composition analysis and blood sampling was performed. Markers of iron status and levels of total antioxidant status (TAS), C-reactive protein (CRP), tumour necrosis factor alpha (TNF-α) and interleukin 6 (IL-6) were measured in the blood. TAS was higher in the HFDEF group (756.57 ± 489.53 ng mL-1) versus the HFDEFLc group (187.04 ± 47.84 ng mL-1; P = 0.022). No more differences were found between groups, or in TAS, CRP, TNF-α and IL-6 concentrations. Also, no differences were found between groups for alanine and aspartate aminotransferases, glucose, total cholesterol, low- and high-density lipoproteins and triglycerides. TAS level was positively correlated with ferritin concentration, IL-6 with TAS and TNF-α with hepcidin level. Supplementation with L. plantarum, L. curvatus and iron in combinations exerts no influence on inflammatory status, lipid profile, hepatic function and serum fasting glucose in rats on a HF iron-deficient diet. © 2024 Society of Chemical Industry.

Synergistic Differential DNA Demethylation Activity of Danshensu (Salvia miltiorrhiza) Associated with Different Probiotics in Nonalcoholic Fatty Liver Disease.

Nonalcoholic fatty liver disease (NAFLD) is a major hepatic disorder occurring in non-alcohol-drinking individuals. Salvianic acid A or Danshensu (DSS, 3-(3, 4-dihydroxyphenyl)-(2R)-lactic acid), derived from the root of Danshen (Salvia miltiorrhiza), has demonstrated heart and liver protective properties. In this work, we investigated the antioxidant activity and hepatoprotective activity of Danshensu alone and in combination with different agents, such as probiotic bacteria (Lactobacillus casei and Lactobacillus acidophilus), against several assays. The inhibition mechanism of the methylation gene biomarkers, such as DNMT-1, MS, STAT-3, and TET-1, against DSS was evaluated by molecular docking and RT-PCR techniques. The physicochemical and pharmacokinetic ADMET properties of DSS were determined by SwissADME and pkCSM. The results indicated that all lipid blood test profiles, including cholesterol (TC), triglycerides (TG), low-density lipoprotein cholesterol (LDL-C), and high-density lipoprotein cholesterol (HDL-C), were reduced after the oral administration of Danshensu combined with probiotics (L. casei and L. acidophilus) that demonstrated good, efficient free radical scavenging activity, measured using anti-oxidant assays. ADMET and drug-likeness properties certify that the DSS could be utilized as a feasible drug since DSS showed satisfactory physicochemical and pharmacokinetic ADMET properties.

Amelioration effect of 18β-Glycyrrhetinic acid on methylation inhibitors in hepatocarcinogenesis -induced by diethylnitrosamine.

suppression of methylation inhibitors (epigenetic genes) in hepatocarcinogenesis induced by diethylnitrosamine using glycyrrhetinic acid. In the current work, we investigated the effect of sole GA combined with different agents such as doxorubicin (DOX) or probiotic bacteria (Lactobacillus rhamanosus) against hepatocarcinogenesis induced by diethylnitrosamine to improve efficiency. The genomic DNA was isolated from rats' liver tissues to evaluate either methylation-sensitive or methylation-dependent resection enzymes. The methylation activity of the targeting genes DLC-1, TET-1, NF-kB, and STAT-3 was examined using specific primers and cleaved DNA products. Furthermore, flow cytometry was used to determine the protein expression profiles of DLC-1 and TET-1 in treated rats' liver tissue. Our results demonstrated the activity of GA to reduce the methylation activity in TET-1 and DLC-1 by 33.6% and 78%, respectively. As compared with the positive control. Furthermore, the association of GA with DOX avoided the methylation activity by 88% and 91% for TET-1 and DLC-1, respectively, as compared with the positive control. Similarly, the combined use of GA with probiotics suppressed the methylation activity in the TET-1 and DLC-1 genes by 75% and 81% for TET-1 and DLC-1, respectively. Also, GA and its combination with bacteria attenuated the adverse effect in hepatocarcinogenesis rats by altering potential methylomic genes such as NF-kb and STAT3 genes by 76% and 83%, respectively. GA has an ameliorative effect against methylation inhibitors in hepatocellular carcinoma (HCC) by decreasing the methylation activity genes.

Evolution of the urinary microbiota in spinal cord injury patients with decubitus ulcer: A snapshot study.

Current microbiome investigations of patients with pressure ulcers (PU) are mainly based on wound swabs and/or biopsy sequencing, leaving the colonization scenario unclear. Urinary microbiota has been never studied. As a part of the prospective ESCAFLOR study, we studied urinary microbiota of spinal cord injury (SCI) patients with PU without any urinary tract infection at the inclusion, collected at two times (at admission [D0] and after 28 days [D28]) during the patient's care, investigated by 16S rDNA metagenomics next generation sequencing. Subgroup analyses were carried out between patients with wounds showing improved evolution versus stagnated/worsened wounds at D28. Analysis was done using EPISEQ® 16S and R software. Among the 12 studied patients, the urinary microbiota of patients with improved wound evolution at D28 (n = 6) presented a significant decrease of microbial diversity. This modification was associated with the presence of Proteobacteria phylum and an increase of Escherichia-Shigella (p = 0.005), as well as the presence of probiotic anaerobic bacteria Lactobacillus and Bifidobacterium. In contrast, Proteus abundance was significantly increased in urine of patients with stagnated/worsened wound evolution (n = 6) (p = 0.003). This study proposes urinary microbiota as a complementary factor indirectly associated with the wound evolution and patient cure. It opens new perspectives for further investigations based on multiple body microbiome comparison to describe the complete scenario of the transmission dynamics of wound-colonizing microorganisms.

Germinated Sang Yod Brown Rice as a Novel Prebiotic for Synbiotic Dietary Supplement Development

This study aimed to investigate the prebiotic properties of germinated Sang Yod brown rice in supporting the growth of the probiotic bacteria Lactobacillus pentosus GP6. Germinated brown rice was dried, ground into powder, and mixed with De Man Rogosa and Sharpe (MRS) broth at 1%, 3%, and 5%. Bacterial cells were counted at 0, 3, 6, 9, 12, and 24 h after incubation at 37°C. The results showed that the concentration of germinated Sang Yod brown rice powder that exhibited the highest bacterial growth was 3% (10.97 log cfu/ml), followed by 5% (10.85 log cfu/ml) and 1% (10.42 log cfu/ml), respectively. The 3% germinated Sang Yod brown rice powder produced a synbiotic dietary supplement with L. pentosus GP6. The results showed that L. pentosus GP6 survived with 10.00-10.30 log cfu/ml cell numbers at 4°C for 6 months. This study demonstrated that germinated Sang Yod brown rice could be implemented as a prebiotic and component of synbiotic dietary supplement products.

Antimicrobial Protein LECT2-b Helps Maintain Gut Microbiota Homeostasis via Selectively Targeting Certain Pathogenic Bacteria.

Antimicrobial peptides/proteins (AMPs) constitute a critical component of gut immunity in animals, protecting the gut from pathogenic bacteria. However, the interactions between AMPs and gut microbiota remain elusive. In this study, we show that leukocyte-derived chemotaxin-2 (LECT2)-b, a recently discovered AMP, helps maintain gut homeostasis in grass carp (Ctenopharyngodon idella), one of the major farmed fish species globally, by directly regulating the gut microbiota. Knockdown of LECT2-b resulted in dysregulation of the gut microbiota. Specifically, LECT2-b deficiency led to the dominance of Proteobacteria, consisting of proinflammatory bacterial species, over Firmicutes, which includes anti-inflammatory bacteria. In addition, the opportunistic pathogenic bacteria genus Aeromonas became the dominant genus replacing the probiotic bacteria Lactobacillus and Bacillus. Further analysis revealed that this effect was due to the direct and selective inhibition of certain pathogenic bacterial species by LECT2-b. Moreover, LECT2-b knockdown promoted biofilm formation by gut microbiota, resulting in tissue damage and inflammation. Importantly, LECT2-b treatment alleviated the negative effects induced by LECT2-b knockdown. These findings highlight the crucial role of LECT2-b in maintaining the gut microbiota homeostasis and mucosal health. Overall, our study provides important data for understanding the roles of AMPs in the regulation of gut homeostasis in animals.

Isolation, purification and characterization of bioactive surfactant from the probiotic bacterium Lactobacillus casei NM512 isolated from infant microbiota

Background Lactobacillus casei NM512 was previously isolated from the feces of breast-fed infants and has great potential for probiotic treatment of diseases that are based on immune deregulation. These strains fulfill the main criteria required for safe human consumption and could therefore be useful in pharmaceutical and therapeutic preparations. However, further studies are needed to evaluate and decipher the in vivo activities of the isolated strains with regard to their immunomodulatory function. Objective This work aims to isolate, identify and characterize the bioactive surfactant component from the probiotic bacterium L. casei NM512. Materials and methods The isolation of the surfactant from L. casei NM512 was performed after incubation the strain for 72 h at 37°C with shaking at 120 rpm. The surfactant extracted from cells by acid precipitation. A combination of different methods (TLC, FT-IR, NMR, and GC mass) was used to analyze the composition of the isolated surfactant. The surfactant was also investigated for its antimicrobial activity using the well agar diffusion method, antioxidant ability targeting the DPPH free radical, Cytotoxicity ability using MTT assay, and anti- inflammatory activity was done by determination the inhibition of nitric oxide (NO) production in RAW 264.7 macrophages. Results and conclusion The obtained data show that the surfactant is a mixture of carbohydrates, lipids and proteins with glycolipopeptide nature that expressed remarkable antibacterial and antioxidant activities. Furthermore the isolated surfactant showed safety by keeping the cell viability and anti-inflammatory activity. Here we introduce a novel biosurfactant for medical and pharmaceutical purposes.

Multi-omics analysis revealing the interplay between gut microbiome and the host following opioid use

ABSTRACT Opioid crisis is an ongoing epidemic since the past several decades in the United States. Opioid use-associated microbial dysbiosis is emerging as a key regulator of intestinal homeostasis and behavioral responses to opioid. However, the mechanistic insight into the role of microbial community in modulating host response is unavailable. To uncover the role of opioid-induced dysbiosis in disrupting intestinal homeostasis we utilized whole genome sequencing, untargeted metabolomics, and mRNA sequencing to identify changes in microbiome, metabolome, and host transcriptome respectively. Morphine treatment resulted in significant expansion of Parasuterella excrementihominis, Burkholderiales bacterium 1_1_47, Enterococcus faecalis, Enterorhabdus caecimuris and depletion of Lactobacillus johnsonii. These changes correlated with alterations in lipid metabolites and flavonoids. Significant alteration in microbial metabolism (metabolism of lipids, amino acids, vitamins and cofactors) and increased expression of virulence factors and biosynthesis of lipopolysaccharides (LPS) and lipoteichoic acid (LTA) were observed in microbiome of morphine-treated animals. In concurrence with changes in microbiome and metabolome extensive changes in innate and adaptive immune response, lipid metabolism, and gut barrier dysfunction were observed in the host transcriptome. Microbiome depleted mice displayed lower levels of inflammation, immune response and tissue destruction compared to mice harboring a dysbiotic microbiome in response to morphine treatment, thus establishing dysbiotic microbiome as mediator of morphine gut pathophysiology. Integrative analysis of multi-omics data highlighted the associations between Parasutterella excrementihominis, Burkholderiales bacterium 1_1_47, Enterococcus faecalis, Enterorhabdus caecimuris and altered levels of riboflavin, flavonoids, and lipid metabolites including phosphocholines, carnitines, bile acids, and ethanolamines with host gene expression changes involved in inflammation and barrier integrity of intestine. Omic analysis also highlighted the role of probiotic bacteria Lactobacillus johnsonii, metabolites flavonoids and riboflavin that were depleted with morphine as important factors for intestinal homeostasis. This study presents for the first time ever an interactive view of morphine-induced changes in microbial metabolism, strain level gut microbiome analysis and comprehensive view of changes in gut transcriptome. We also identified areas of potential therapeutic interventions to limit microbial dysbiosis and present a unique resource to the opioid research community.