Peptide-functionalized gold nanoparticles for boron neutron capture therapy with the potential to use in Glioblastoma treatment.

Glioblastoma is a highly aggressive glioma with limited treatment options. Boron neutron capture therapy (BNCT) offers a promising approach for refractory cancers, utilizing boron-10 (10B) and thermal neutrons to generate cytotoxic particles. Effective BNCT depends on selective targeting and retention of 10B in tumors. Current BNCT drugs face issues with rapid clearance and poor tumor accumulation. To address this, we developed gold nanoparticles (AuNPs) functionalized with cyclic arginine-glycine-aspartic acid (cRGD) peptides as a nanocarrier for Sodium Mercaptododecaborate (BSH), resulting in AuNPs-BSH&PEG-cRGD. In vitro, AuNPs-BSH&PEG-cRGD increased 10B content in GL261 glioma cells by approximately 2.5-fold compared to unmodified AuNPs-BSH&PEG, indicating enhanced targeting due to cRGD's affinity for integrin receptor αvß3. In a subcutaneous glioma mouse model, 6 h post-intratumoral administration, the 10B concentration in tumors was 17.98 µg/g for AuNPs-BSH&PEG-cRGD, significantly higher than 0.45 µg/g for BSH. The tumor-to-blood (T/B) and tumor-to-normal tissue (T/N) ratios were also higher for AuNPs-BSH&PEG-cRGD, suggesting improved targeting and retention. This indicates that AuNPs-BSH&PEG-cRGD may enhance BNCT efficacy and minimize normal tissue toxicity. In summary, this study provides a novel strategy for BSH delivery and may broaden the design vision of BNCT nano-boron capture agents.

Levilactobacillus brevis from carnivores can ameliorate hypercholesterolemia: In vitro and in vivo mechanistic evidence.

AIMS: The aim was to explore the probiotic and hypocholesterolaemic potential of two Levilactobacillus brevis strains of carnivore origin along with selected underlying mechanisms. METHODS AND RESULTS: Levilactobacillus brevis MT950194 and L. brevis MW365351 were analysed in vitro for oro-gastro-intestinal stress tolerance, cholesterol reduction, cholesterol adsorption (through scanning electron microscopy) and bile salt hydrolase (BSH) activity. Strains could survive (>80%) in oro-gastro-intestinal conditions and reduce high amount of cholesterol (35% and 54%) from media containing bile salts (0.3%) as compared with Lactobacillus acidophilus ATCC 4356 and presented the least pathogenicity towards mammalian cells. Exopolysaccharide production, cell surface cholesterol adherence and BSH activity were witnessed as possible cholesterol-lowering mechanisms. In in vivo experiment, the treatments of hypercholesterolaemic rats with L. brevis MT950194, L. brevis MW365351 and their mixture led to significant (p < 0.05) reduction in serum and hepatic cholesterol, low-density lipids, cholesterol ratio, liver steatosis and size of adipocytes. It further ameliorated diet-induced changes in hepatic enzymes. CONCLUSIONS: Levilactobacillus brevis MT950194 and L. brevis MW365351 from carnivores have probiotic pharmacological potential and can reduce serum cholesterol through surface adherence and BSH production. SIGNIFICANCE AND IMPACT OF THE STUDY: These strains may be utilized in treating hypercholesterolaemia and production of low-fat functional foods.

Quantitation of residual D positive red cells in D negative recipients of D positive solid organ transplants.

BACKGROUND: Solid organ transplants (SOT) from D positive donors are potentially sensitising events for D negative recipients. For this reason, it is important to quantify the presence of residual D positive red blood cells (RBCs) in the recipient's circulation and calculate the correct dose of prophylactic anti-D (PAD) required to prevent sensitisation. This is especially important in females of child-bearing potential where the presence of allo anti-D can, at worst, cause the death of the fetus in future pregnancies. OBJECTIVE: This study aimed to identify the patient characteristics of D positive SOT cases referred to Red Cell Immunohaematology, NHSBT for flow cytometry investigation. This information could indicate improvements required in the current testing methodology, as well as to the calculations used to prescribe PAD for this patient group. METHODS: Samples were investigated using a Beckman Coulter Navios Flow Cytometer using BRAD3-FITC (anti-D), AEVZ5.3-FITC (isotype matched negative control) and BIRMA17C-PE (granulocyte exclusion reagent). Mollison's calculation was used to estimate the dose of PAD required to prevent sensitisation in the D negative recipients. The calculation was adapted to consider the presence of organ donor D positive adult RBCs in the circulation of recipients instead of, larger, fetal RBCs. RESULTS: Samples from 20 patients, all female, aged 14-53 years (one 2-year-old outlier) were referred from 2016 to September 2020. The transplants were-liver (n = 6), kidney (n = 6) and lung (n = 8). D positive cell populations were identified in 11 cases (0.1-8.0 ml); and required PAD (500-1500 IU). From these 20 patients, 10 sent a follow-up sample, where 8 required PAD top-up due to the detection of residual D positive cells (0.1-2 ml)-liver (n = 1), kidney (n = 1) and lung transplant (n = 6). CONCLUSION: All patients in the study were D negative females, in which 18 were considered by guidelines to be of childbearing potential (2-42 years old) and 2 were >50 years old. Referrals demonstrate an awareness for the correct calculation of PAD to prevent D sensitisation. The sample size is small, but top up requirement in 8/20 of cases demonstrates accurate quantification is clearly needed to ensure the appropriate dose of PAD is provided.

Characterization of substrate specificity and inhibitory mechanism of bile salt hydrolase from Lactobacillus reuteri CRL 1098 using molecular docking analysis.

OBJECTIVES: To elucidate the molecular mechanisms involved in the substrate interaction of the bile salt hydrolase of Lactobacillus reuteri CRL 1098 (LrBSH) with bile acids (BAs) and to evaluate potential enzyme inhibitors based on computer and in vitro modeling assays. RESULTS: Asp19, Asn79, and Asn171 participated in the LrBSH interaction with all BAs tested while Leu56 and Glu 222 played an important role in the interaction with glyco- and tauro-conjugated BAs, respectively. A great percentage of hydrophobic and polar interactions were responsible for the binding of LrBSH with glyco- and tauro-conjugated BAs, respectively. Remarkably, the four binding pocket loops participated in the substrate binding site of LrBSH unlike most of the reported BSHs. Inhibition assays showed that ascorbic acid, citric acid, penicillin G, and ciprofloxacin decreased LrBSH activity by 47.1%, 40.14%, 28.8%, and 9%, respectively. Docking analysis revealed that tetracycline and caffeic acid phenethyl ester had the low binding energy (-7.32 and -7.19 kcal/mol, respectively) and resembled the interaction pattern of GDCA (-6.88 kcal/mol) while penicillin (-6.25 kcal/mol) and ascorbic acid (-5.98 kcal/mol) interacted at a longer distance. CONCLUSION: This study helps to delve into the molecular mechanisms involved in the recognition of substrates and potential inhibitors of LrBSH.

Intestinal flora imbalance affects bile acid metabolism and is associated with gallstone formation.

BACKGROUND: The gut microbiota participates in the metabolism of substances and energy, promotes the development and maturation of the immune system, forms the mucosal barrier, and protects the host from pathogen attacks. Although the pathogenesis of cholesterol gallstones is still not clear, studies have suggested that gut microbiota dysbiosis plays an important role in their formation. METHODS: Microbial DNA from faeces of normal control patients and those of patients with calculi was subjected to 16S rRNA gene sequencing to detect gene expression changes in intestinal microbes. ELISA kits were used to measure free bile acids, secondary bile acids and coprostanol according to the manufacturer's instructions. The relationship between flora and their metabolites was then analysed. RESULTS: In the gallstone group, the diversity of intestinal bacteria and the abundances of certain phylogroups were significantly decreased (p < 0.05), especially Firmicutes (p < 0.05), the largest phylum represented by the gut microbiota. This study found an increase in free bile acids (p < 0.001) and secondary bile acids (p < 0.01) in the enterohepatic circulation. Bile salt hydrolase activity was not related to the abundances of BSH-active bacteria. 7a-dehydroxylating gut bacteria were significantly increased (p < 0.01), whereas cholesterol-lowering bacteria were significantly reduced (p < 0.05). The Ruminococcus gnavus group could be used as a biomarker to distinguish the gallstone group from the control group. CONCLUSION: We conclude that intestinal flora imbalance affects bile acid and cholesterol metabolism and is associated with gallstone formation.

Protein resonance assignment by BSH-CP-based 3D solid-state NMR experiments: A practical guide.

Solid-state NMR (ssNMR) spectroscopy has evolved into a powerful method to obtain structural information and to study the dynamics of proteins at atomic resolution and under physiological conditions. The method is especially well suited to investigate insoluble and noncrystalline proteins that cannot be investigated easily by X-ray crystallography or solution NMR. To allow for detailed analysis of ssNMR data, the assignment of resonances to the protein atoms is essential. For this purpose, a set of three-dimensional (3D) spectra needs to be acquired. Band-selective homo-nuclear cross-polarization (BSH-CP) is an effective method for magnetization transfer between carbonyl carbon (CO) and alpha carbon (CA) atoms, which is an important transfer step in multidimensional ssNMR experiments. This tutorial describes the detailed procedure for the chemical shift assignment of the backbone atoms of 13 C-15 N-labeled proteins by BSH-CP-based 13 C-detected ssNMR experiments. A set of six 3D experiments is used for unambiguous assignment of the protein backbone as well as certain side-chain resonances. The tutorial especially addresses scientists with little experience in the field of ssNMR and provides all the necessary information for protein assignment in an efficient, time-saving approach.

Lactobacillus mucosae DPC 6426 as a bile-modifying and immunomodulatory microbe.

BACKGROUND: Lactobacillus mucosae DPC 6426 has previously demonstrated potentially cardio-protective properties, in the form of dyslipidaemia and hypercholesterolemia correction in an apolipoprotein-E deficient mouse model. This study aims to characterise the manner in which this microbe may modulate host bile pool composition and immune response, in the context of cardiovascular disease. Lactobacillus mucosae DPC 6426 was assessed for bile salt hydrolase activity and specificity. The microbe was compared against several other enteric strains of the same species, as well as a confirmed bile salt hydrolase-active strain, Lactobacillus reuteri APC 2587. RESULTS: Quantitative bile salt hydrolase assays revealed that enzymatic extracts from Lactobacillus reuteri APC 2587 and Lactobacillus mucosae DPC 6426 demonstrate the greatest activity in vitro. Bile acid profiling of porcine and murine bile following incubation with Lactobacillus mucosae DPC 6426 confirmed a preference for hydrolysis of glyco-conjugated bile acids. In addition, the purified exopolysaccharide and secretome of Lactobacillus mucosae DPC 6426 were investigated for immunomodulatory capabilities using RAW264.7 macrophages. Gene expression data revealed that both fractions stimulated increases in interleukin-6 and interleukin-10 gene transcription in the murine macrophages, while the entire secretome was necessary to increase CD206 transcription. Moreover, the exopolysaccharide elicited a dose-dependent increase in nitric oxide and interleukin-10 production from RAW264.7 macrophages, concurrent with increased tumour necrosis factor-α secretion at all doses. CONCLUSIONS: This study indicates that Lactobacillus mucosae DPC 6426 modulates both bile pool composition and immune system tone in a manner which may contribute significantly to the previously identified cardio-protective phenotype.

A Comprehensive Genome Survey Provides Novel Insights into Bile Salt Hydrolase (BSH) in Lactobacillaceae.

Bile salt hydrolase (BSH) is a well-known enzyme that has been commonly characterized in probiotic bacteria, as it has cholesterol-lowering effects. However, its molecular investigations are scarce. Here, we build a local database of BSH sequences from Lactobacillaceae (BSH⁻SDL), and phylogenetic analysis and homology searches were employed to elucidate their comparability and distinctiveness among species. Evolutionary study demonstrates that BSH sequences in BSH⁻SDL are divided into five groups, named BSH A, B, C, D and E here, which can be the genetic basis for BSH classification and nomenclature. Sequence analysis suggests the differences between BSH-active and BSH-inactive proteins clearly, especially on site 82. In addition, a total of 551 BSHs from 107 species are identified from 451 genomes of 158 Lactobacillaceae species. Interestingly, those bacteria carrying various copies of BSH A or B can be predicted to be potential cholesterol-lowering probiotics, based on the results of phylogenetic analysis and the subtypes that those previously reported BSH-active probiotics possess. In summary, this study elaborates the molecular basis of BSH in Lactobacillaceae systematically, and provides a novel methodology as well as a consistent standard for the identification of the BSH subtype. We believe that high-throughput screening can be efficiently applied to the selection of promising candidate BSH-active probiotics, which will advance the development of healthcare products in cholesterol metabolism.

Evaluation of some in vitro probiotic properties of Lactobacillus fermentum Strains.

This study aimed to check the in vitro probiotic properties of eleven Lactobacillus fermentum strains previously isolated from fermented dairy products and infant faeces. These cultures were tested for their tolerance to different pH such as 2.0, 2.5, 3.0, 3.5 and 6.5, bile salt hydrolysis and cell surface hydrophobicity. All the strains were persistent at pH 3.5 for 3 h whereas only faecal origin isolates such as L. fermentum BIF-19, BIF-20, BIF-18 and MTCC 8711 had shown considerable growth at pH 2.5. The strains NCDC-400, MTCC 8711, BIF-18, BIF-19 and BIF-20 showed slight to intense precipitation zone of bile salt hydrolase activity by agar plate assay. The strain L. fermentum BIF-19 exhibited best preliminary probiotic properties was selected for the adhesion to Caco-2 cell lines, which shows similar adhesion to that observed for standard probiotic Lactobacillus rhamnosus GG.

Mechanisms responsible for the hypocholesterolaemic effect of regular consumption of probiotics.

CVD affect a large proportion of the world's population, with dyslipidaemia as the major risk factor. The regular consumption of both probiotic bacteria and yeast has been associated with improvement in the serum lipid profile. Thus, the present review aims to describe and discuss the potential mechanisms responsible for the hypocholesterolaemic effect of regular consumption of probiotic bacteria and yeast. Regarding the hypocholesterolaemic effect of probiotic bacteria, the potential mechanisms responsible include: deconjugation of bile salts; modulation of lipid metabolism; and decreased absorption of intestinal cholesterol through co-precipitation of intestinal cholesterol with the deconjugated bile salts, incorporation and assimilation of cholesterol in the cell membrane of the probiotics, intestinal conversion of cholesterol in coprostanol, and inhibition of the expression of the intestinal cholesterol transporter Niemann-Pick C1 like 1 (NPC1L1) in the enterocytes. The potential mechanisms responsible for the hypocholesterolaemic effect of probiotic yeasts include: deconjugation of bile salts; co-precipitation of intestinal cholesterol with the deconjugated bile salts; incorporation and assimilation of cholesterol in the cell membrane; and inhibition of hepatic cholesterol synthesis. The regular consumption of probiotic bacteria and yeast, as a non-pharmaceutical approach to help manage cardiovascular risk, holds promise, according to the beneficial hypocholesterolaemic effects described herein. However, the hypocholesterolaemic effects vary according to the strains used, the physiological state of the host, and the type of diet to which the probiotics are added. Further studies are necessary to fill the gaps with regard to the knowledge related to this topic.

Effect of prebiotic carbohydrates on growth, bile survival and cholesterol uptake abilities of dairy-related bacteria.

BACKGROUND: Three strains of lactic acid bacteria and one probiotic Bifidobacterium strain sourced from milk origin were considered to select for the best synbiotic-like combination for cholesterol uptake ability. For that purpose, fermentative characteristics, bile salt hydrolase activity, bile survival and cholesterol removal were assessed in the presence of different carbohydrates. RESULTS: Carbohydrate fermentability was highly variable among the different strains, and lactulose was the only prebiotic to favour growth of all strains, whereas pectin led to low population regardless of the strain. Bile survival of bacteria could be improved by the preferred carbon source and was related to their bile salt hydrolase activities. All together, our results showed that the most advantageous synbiotic-like combinations to achieve cholesterol uptake abilities were Lactobacillus delbrueckii subsp. bulgaricus LB 340 with raffinose, Streptococcus thermophilus TA040 or Lactobacillus rhamnosus LBRE-LSAS with lactulose, and Bifidobacterium animalis subsp. lactis Bb12 with mannitol. CONCLUSION: The suggested synbiotics may represent new promising functional dairy additives.

Fermentation dynamics of bile salt hydrolase production in Heyndrickxia coagulans ATCC 7050 and Lactiplantibacillus plantarum ATCC 10012: Addressing ninhydrin assay limitations with a novel HPTLC-MS method.

Bile salt hydrolase (BSH), a pivotal enzyme in cholesterol management, holds significant promise in both human and animal subjects. This study investigated the effect of fermentation dynamics in Heyndrickxia coagulans ATCC 7050 and Lactiplantibacillus plantarum ATCC 10012 to enhance BSH production. Cultivation of cultures in MRS and M17 media revealed that MRS medium enhanced BSH production by 235.98 % in H. coagulans ATCC 7050 and 147.37 % in L. plantarum ATCC 10012, compared to M 17 medium. Additionally, varying oxygen concentration levels indicated that H. coagulans ATCC 7050 exhibited its minimum doubling time of 79.8 ±â€¯0.64 min in anaerobic conditions, whereas L. plantarum ATCC 10012 demonstrated its minimum doubling time of 85.5 ±â€¯1.2 min under microaerophilic conditions. However, their highest BSH activity was observed during the stationary phase under anaerobic conditions, yielding 17.14 ±â€¯0.78 U/mL by H. coagulans ATCC 7050 and 19.04 ±â€¯0.81 U/mL by L. plantarum ATCC 10012. Furthermore, it was observed that both organisms did not retain BSH within their cells. BSH activity was assessed using ninhydrin assay that detected free taurine liberated from sodium taurocholate. However, ninhydrin can yield false-positive results owing to its interaction with other free amino acids. To subjugate this limitation, the study introduced a novel and sensitive HPTLC-MS method capable of accurately detecting taurine. By comprehending fermentation dynamics and selecting appropriate conditions, BSH production increased 2.1-fold in both organisms. These findings illuminate critical insights, offering a pathway for novel strategies to enhance the BSH-producing capabilities of these LAB strains.

Bacteroides fragilis alleviates necrotizing enterocolitis through restoring bile acid metabolism balance using bile salt hydrolase and inhibiting FXR-NLRP3 signaling pathway.

Necrotizing enterocolitis (NEC) is a leading cause of morbidity and mortality in premature infants with no specific treatments available. We aimed to identify the molecular mechanisms underlying NEC and investigate the therapeutic effects of Bacteroides fragilis on NEC. Clinical samples of infant feces, bile acid-targeted metabolomics, pathological staining, bioinformatics analysis, NEC rat model, and co-immunoprecipitation were used to explore the pathogenesis of NEC. Taxonomic characterization of the bile salt hydrolase (bsh) gene, enzyme activity assays, 16S rRNA sequencing, and organoids were used to explore the therapeutic effects of B. fragilis on NEC-related intestinal damage. Clinical samples, NEC rat models, and in vitro experiments revealed that total bile acid increased in the blood but decreased in feces. Moreover, the levels of FXR and other bile acid metabolism-related genes were abnormal, resulting in disordered bile acid metabolism in NEC. Taurochenodeoxycholic acid accelerated NEC pathogenesis and taurodeoxycholate alleviated NEC. B. fragilis displayed bsh genes and enzyme activity and alleviated intestinal damage by restoring gut microbiota dysbiosis and bile acid metabolism abnormalities by inhibiting the FXR-NLRP3 signaling pathway. Our results provide valuable insights into the therapeutic role of B. fragilis in NEC. Administering B. fragilis may substantially alleviate intestinal damage in NEC.

Notch signaling and Bsh homeodomain activity are integrated to diversify Drosophila lamina neuron types.

Notch signaling is an evolutionarily conserved pathway for specifying binary neuronal fates, yet how it specifies different fates in different contexts remains elusive. In our accompanying paper, using the Drosophila lamina neuron types (L1-L5) as a model, we show that the primary homeodomain transcription factor (HDTF) Bsh activates secondary HDTFs Ap (L4) and Pdm3 (L5) and specifies L4/L5 neuronal fates. Here we test the hypothesis that Notch signaling enables Bsh to differentially specify L4 and L5 fates. We show asymmetric Notch signaling between newborn L4 and L5 neurons, but they are not siblings; rather, Notch signaling in L4 is due to Delta expression in adjacent L1 neurons. While Notch signaling and Bsh expression are mutually independent, Notch is necessary and sufficient for Bsh to specify L4 fate over L5. The NotchON L4, compared to NotchOFF L5, has a distinct open chromatin landscape which allows Bsh to bind distinct genomic loci, leading to L4-specific identity gene transcription. We propose a novel model in which Notch signaling is integrated with the primary HDTF activity to diversify neuron types by directly or indirectly generating a distinct open chromatin landscape that constrains the pool of genes that a primary HDTF can activate.

First independent validation of the proton-boron capture therapy concept.

Boron has been suggested to enhance the biological effectiveness of proton beams in the Bragg peak region via the p + 11B → 3α nuclear capture reaction. However, a number of groups have observed no such enhancement in vitro or questioned its proposed mechanism recently. To help elucidate this phenomenon, we irradiated DU145 prostate cancer or U-87 MG glioblastoma cells by clinical 190 MeV proton beams in plateau or Bragg peak regions with or without 10B or 11B isotopes added as sodium mercaptododecaborate (BSH). The results demonstrate that 11B but not 10B or other components of the BSH molecule enhance cell killing by proton beams. The enhancement occurs selectively in the Bragg peak region, is present for boron concentrations as low as 40 ppm, and is not due to secondary neutrons. The enhancement is likely initiated by proton-boron capture reactions producing three alpha particles, which are rare events occurring in a few cells only, and their effects are amplified by intercellular communication to a population-level response. The observed up to 2-3-fold reductions in survival levels upon the presence of boron for the studied prostate cancer or glioblastoma cells suggest promising clinical applications for these tumour types.

Evaluation of sodium borocaptate (BSH) and boronophenylalanine (BPA) as boron delivery agents for neutron capture therapy (NCT) of cancer: an update and a guide for the future clinical evaluation of new boron delivery agents for NCT.

Boron neutron capture therapy (BNCT) is a cancer treatment modality based on the nuclear capture and fission reactions that occur when boron-10, a stable isotope, is irradiated with neutrons of the appropriate energy to produce boron-11 in an unstable form, which undergoes instantaneous nuclear fission to produce high-energy, tumoricidal alpha particles. The primary purpose of this review is to provide an update on the first drug used clinically, sodium borocaptate (BSH), by the Japanese neurosurgeon Hiroshi Hatanaka to treat patients with brain tumors and the second drug, boronophenylalanine (BPA), which first was used clinically by the Japanese dermatologist Yutaka Mishima to treat patients with cutaneous melanomas. Subsequently, BPA has become the primary drug used as a boron delivery agent to treat patients with several types of cancers, specifically brain tumors and recurrent tumors of the head and neck region. The focus of this review will be on the initial studies that were carried out to define the pharmacokinetics and pharmacodynamics of BSH and BPA and their biodistribution in tumor and normal tissues following administration to patients with high-grade gliomas and their subsequent clinical use to treat patients with high-grade gliomas. First, we will summarize the studies that were carried out in Japan with BSH and subsequently at our own institution, The Ohio State University, and those of several other groups. Second, we will describe studies carried out in Japan with BPA and then in the United States that have led to its use as the primary drug that is being used clinically for BNCT. Third, although there have been intense efforts to develop new and better boron delivery agents for BNCT, none of these have yet been evaluated clinically. The present report will provide a guide to the future clinical evaluation of new boron delivery agents prior to their clinical use for BNCT.

Collaborative Metabolism: Gut Microbes Play a Key Role in Canine and Feline Bile Acid Metabolism.

Bile acids, produced by the liver and secreted into the gastrointestinal tract, are dynamic molecules capable of impacting the overall health of dogs and cats in many contexts. Importantly, the gut microbiota metabolizes host primary bile acids into chemically distinct secondary bile acids. This review explores the emergence of new literature connecting microbial-derived bile acid metabolism to canine and feline health and disease. Moreover, this review highlights multi-omic methodologies for translational research as an area for continued growth in veterinary medicine aimed at accelerating microbiome science and medicine as it pertains to bile acid metabolism in dogs and cats.

Heavy metal contamination of overlying waters and bed sediments of Haihe Basin in China.

The Haihe Basin is in an area of high population density and rapid economic development, and is one of the most polluted river basins in China. Examination of heavy metals (Cd, Co, Cr, Cu, Mn, Ni, Pb and Zn) in overlying waters and surface sediments in rivers was conducted in the basin's seven watersheds. Cd concentrations of overlying river waters exceeded Chinese environmental quality standard values for surface water (>0.010 mg/L) at 90% of stations. In surface river sediments, average concentrations of Cd, Co, Cr, Cu, Mn, Ni, Pb and Zn in the basin were 0.364, 13.4, 81.9, 53.3, 435, 27.8, 20.0 and 256 mg/kg, respectively. Cd, Zn and Cu were the most anthropogenically enriched elements, as indicated by enrichment factor (EF) values>1.5; EF values were highest for these metals in the Zi Ya He (ZYH) and Zhang Wei He (ZWH) watersheds. Cd in surface river sediments showed a high potential ecological risk (PER) in the ZYH and ZWH watersheds. The comprehensive PER due to all studied metals was high at many stations, especially in the ZYH and ZWH watersheds. The results indicate that heavy metal contamination in the rivers of the Haihe Basin should be considered when developing basin management strategies for protecting the aquatic environment.

Bifidobacterium longum LBUX23 Isolated from Feces of a Newborn; Potential Probiotic Properties and Genomic Characterization.

Bifidobacterium longum is considered a microorganism with probiotic potential, which has been extensively studied, but these probiotic effects are strain dependent. This work aims to characterize the probiotic potential, based on the biochemical and genomic functionality, of B. longum LBUX23, isolated from neonates' feces. B. longum LBUX23 contains one circular genome of 2,287,838 bp with a G+C content of 60.05%, no plasmids, no CRISPR-Cas operon, possesses 56 tRNAs, 9 rRNAs, 1 tmRNA and 1776 coding sequences (CDSs). It has chromosomally encoded resistance genes to ampicillin and dicloxacillin, non-hemolytic activity, and moderate inhibition of Escherichia coli ATCC 25922 and to some emergent pathogen's clinical strains. B. longum LBUX23 was able to utilize lactose, sucrose, fructooligosaccharides (FOS), and lactulose. The maximum peak of bacterial growth was observed in sucrose and FOS at 6 h; in lactose and lactulose, it was shown at 8 h. B. longum LBUX23 can survive in gastrointestinal conditions (pH 4 to 7). A decrease in survival (96.5 and 93.8%) was observed at pH 3 and 3.5 during 120 min. argC, argH, and dapA genes could be involved in this tolerance. B. longum LBUX23 can also survive under primary and secondary glyco- or tauro-conjugated bile salts, and a mixture of bile salts due to the high extracellular bile salt hydrolase (BSH) activity (67.3 %), in taurocholic acid followed by taurodeoxycholic acid (48.5%), glycocholic acid (47.1%), oxgall (44.3%), and glycodeoxycholic acid (29.7%) probably due to the presence of the cbh and gnlE genes which form an operon (start: 119573 and end: 123812). Low BSH activity was determined intracellularly (<7%), particularly in glycocholic acid; no intracellular activity was shown. B. longum LBUX23 showed antioxidant effects in DPPH radical, mainly in intact cells (27.4%). In the case of hydroxyl radical scavenging capacity, cell debris showed the highest reduction (72.5%). In the cell-free extract, superoxide anion radical scavenging capacity was higher (90.5%). The genome of B. longum LBUX23 contains PNPOx, AhpC, Bcp, trxA, and trxB genes, which could be involved in this activity. Regarding adherence, it showed adherence up to 5% to Caco-2 cells. B. longum LBUX23 showed in vitro potential probiotic properties, mainly in BSH activity and antioxidant capacity, which indicates that it could be a good candidate for antioxidant or anti-cholesterol tests using in vivo models.

Isolation and Characterization of Lactic Acid Bacteria With Probiotic Attributes From Different Parts of the Gastrointestinal Tract of Free-living Wild Boars in Hungary.

Lactic acid bacteria (LAB) in the microbiota play an important role in human and animal health and, when used as probiotics, can contribute to an increased growth performance in livestock management. Animals living in their native habitat can serve as natural sources of microorganisms, so isolation of LAB strains from wild boars could provide the opportunity to develop effective probiotics to improve production in swine industry. In this study, the probiotic potential of 56 LAB isolates, originated from the ileum, colon, caecum and faeces of 5 wild boars, were assessed in vitro in details. Their taxonomic identity at species level and their antibacterial activity against four representative strains of potentially pathogenic bacteria were determined. The ability to tolerate low pH and bile salt, antibiotic susceptibility, bile salt hydrolase activity and lack of hemolysis were tested. Draft genome sequences of ten Limosilactobacillus mucosae and three Leuconostoc suionicum strains were determined. Bioinformatic analysis excluded the presence of any known acquired antibiotic resistance genes. Three genes, encoding mesentericin B105 and two different bacteriocin-IIc class proteins, as well as two genes with possible involvement in mesentericin secretion (mesE) and transport (mesD) were identified in two L. suionicum strains. Lam29 protein, a component of an ABC transporter with proved function as mucin- and epithelial cell-adhesion factor, and a bile salt hydrolase gene were found in all ten L. mucosae genomes. Comprehensive reconsideration of all data helps to select candidate strains to assess their probiotic potential further in animal experiments.