scholarly journals Isolation of Novel Probiotic Lactobacillus and Enterococcus Strains From Human Salivary and Fecal Sources

2020 ◽  
Vol 11 ◽  
Author(s):  
Homa Bazireh ◽  
Parvin Shariati ◽  
Sadegh Azimzadeh Jamalkandi ◽  
Ali Ahmadi ◽  
Mohammad Ali Boroumand

Probiotics are non-pathogenic microorganisms that can interact with the gastrointestinal microbiota. They have numerous beneficial health effects that include enhancement of the host immune response, antiallergic, antimicrobial, anti-cancer, and anti-inflammatory properties. Probiotics are capable of restoring the impaired microbiome of a dysbiotic gut. They can be isolated from different environments. However, it is frequently suggested that probiotics for human use should come from human sources. The objective of this study was to isolate and characterize novel probiotic strains from the saliva and feces of healthy human individuals. To meet the criteria for probiotic attributes, the isolates were subjected to numerous standard morphological and biochemical tests. These tests included Gram staining, catalase tests, antibiotic susceptibility testing, hemolytic and antagonistic evaluation, tolerance tests involving temperature, NaCl levels, pH and bile salts, adherence ability assays, and genotypic characterization involving 16S rRNA gene sequencing. From 26 saliva and 11 stool samples, 185 microbial strains were isolated. Based on morphological and biochemical characteristics, 14 potential probiotic candidates were selected and identified genotypically. The new strains belonged to Lactobacillus fermentum, Enterococcus faecium, and Enterococcus hire. The selected strains were non-hemolytic, showed high tolerance to low pH and bile salts, and strong adherence abilities. Furthermore, the strains displayed a wide range of antimicrobial activities, particularly against antibiotic-resistant pathogens such as methicillin resistant Staphylococcus aureus (MRSA). Moreover, five of the selected isolates demonstrated antiproliferative features against human colon cancer cell line (Caco-2). The results of this investigation confirm the diversity of microbial populations in the human gut and saliva, and since these strains are of human origin, they will highly likely display maximal activities in food and drugs set for human use. Hence, the new strains of this study require additional in vivo experiments to assess their health-promoting effects.

1995 ◽  
Vol 15 (8) ◽  
pp. 4648-4656 ◽  
Author(s):  
M H Paalman ◽  
S L Henderson ◽  
B Sollner-Webb

We show that the mouse ribosomal DNA (rDNA) spacer promoter acts in vivo to stimulate transcription from a downstream rRNA gene promoter. This augmentation of mammalian RNA polymerase I transcription is observed in transient-transfection experiments with three different rodent cell lines, under noncompetitive as well as competitive transcription conditions, over a wide range of template concentrations, whether or not the enhancer repeats alone stimulate or repress expression from the downstream gene promoter. Stimulation of gene promoter transcription by the spacer promoter requires the rDNA enhancer sequences to be present between the spacer promoter and gene promoter and to be oriented as in native rDNA. Stimulation also requires that the spacer promoter be oriented toward the enhancer and gene promoter. However, stimulation does not correlate with transcription from the spacer promoter because the level of stimulation is not altered by either insertion of a functional mouse RNA polymerase I transcriptional terminator between the spacer promoter and enhancer or replacement with a much more active heterologous polymerase I promoter. Further analysis with a series of mutated spacer promoters indicates that the stimulatory activity does not reside in the major promoter domains but requires the central region of the promoter that has been correlated with enhancer responsiveness in vivo.


1993 ◽  
Vol 264 (3) ◽  
pp. F480-F489 ◽  
Author(s):  
G. Iervasi ◽  
A. Clerico ◽  
S. Berti ◽  
A. Pilo ◽  
F. Vitek ◽  
...  

125I-labeled atrial natriuretic peptide (ANP) was bolus injected into seven healthy human male subjects on an unrestricted diet (sodium intake ranging from 80 to 300 mmol/day). A high-performance liquid chromatographic procedure was used to purify the labeled hormone and the principal labeled metabolites in venous plasma samples collected up to 50 min after injection. The main ANP kinetic parameters were derived from the disappearance curves of the 125I-ANP, which were satisfactorily fitted by a biexponential function in all subjects. Newly produced ANP initially distributes in a large space (plasma-equivalent volume is 12.1 +/- 3.6 l/m2 body surface); the hormone rapidly leaves this sampling space through both degradation and distribution in peripheral spaces, as indicated by the single-pass mean transit time through the sampling space (3.9 +/- 1.2 min). The mean residence time in the body (22.7 +/- 23.1 min) and the plasma-equivalent total distribution volume (30.9 +/- 12.0 l/m2) indicate that ANP is also widely distributed outside the initial space. Metabolic clearance rate (MCR) values were distributed across a wide range (from 740 to 2,581 ml.min-1 x m-2) and were shown to correlate strongly with the daily urinary excretion of sodium. These results indicate that: 1) newly produced ANP is rapidly distributed and degraded, 2) the body pool of the hormone can be considered as a combination of two exchanging spaces, 3) circulating ANP is < or = 1/15 of the body pool, and 4) MCR of ANP is closely related to sodium intake, at least in normal subjects on a free sodium intake diet.


2013 ◽  
Vol 2013 ◽  
pp. 1-11 ◽  
Author(s):  
Amy B. Howell ◽  
Doris H. D'Souza

Pomegranates have been known for hundreds of years for their multiple health benefits, including antimicrobial activity. The recent surge in multidrug-resistant bacteria and the possibility of widespread global virus pandemics necessitate the need for additional preventative and therapeutic options to conventional drugs. Research indicates that pomegranates and their extracts may serve as natural alternatives due to their potency against a wide range of bacterial and viral pathogens. Nearly every part of the pomegranate plant has been tested for antimicrobial activities, including the fruit juice, peel, arils, flowers, and bark. Many studies have utilized pomegranate peel with success. There are various phytochemical compounds in pomegranate that have demonstrated antimicrobial activity, but most of the studies have found that ellagic acid and larger hydrolyzable tannins, such as punicalagin, have the highest activities. In some cases the combination of the pomegranate constituents offers the most benefit. The positive clinical results on pomegranate and suppression of oral bacteria are intriguing and worthy of further study. Much of the evidence for pomegranates’ antibacterial and antiviral activities against foodborne pathogens and other infectious disease organisms comes fromin vitrocell-based assays, necessitating further confirmation ofin vivoefficacy through human clinical trials.


2019 ◽  
Author(s):  
Lance Daharsh ◽  
Amanda E. Ramer-Tait ◽  
Qingsheng Li

AbstractBackgroundHumanized mice featuring a functional human immune system are an important pre-clinical model for examining immune responses to human-specific pathogens. This model has been widely utilized to study human diseases that are otherwise impossible or difficult to investigate in humans or with other animal models. However, one limitation of using humanized mice is their native murine gut microbiome, which significantly differs from the one found in humans. These differences may be even greater for mice housed and bred in specific pathogen free conditions. Given the importance of the gut microbiome to human health and disease, these differences may profoundly impact the ability to translate the results from humanized mice studies to human disease. Further, there is a critical need for improved pre-clinical models to study the complex in vivo relationships of the gut microbiome, immune system, and human disease. We therefore created double humanized mice with both a functional human immune system and stable human-like gut microbiome.ResultsSurgery was performed on NOD.Cg-PrkdcscidII2rgtm1Wjl/SzJ (NSG) mice to create bone-marrow, liver, thymus (BLT) humanized mice. After immune reconstitution, mice were treated with broad spectrum antibiotics to deplete murine gut bacteria and then transplanted with fecal material from healthy human donors. Characterization of 173 fecal samples obtained from 45 humanized mice revealed that double humanized mice had unique 16S rRNA gene profiles consistent with those of the individual human donor samples. Importantly, transplanted human-like gut microbiomes were stable in mice for the duration of the study, up to 14.5 weeks post-transplant. Microbiomes of double humanized mice also harbored predicted functional capacities that more closely resembled those of the human donors compared to humanized mice.ConclusionsHere, we describe successful engraftment of a stable human microbiome in BLT humanized mice to further improve this preclinical humanized mouse model. These double humanized mice represent a unique and tractable new model to study the complex relationships between the human gut microbiome, human immune system, and human disease in vivo.


2013 ◽  
Vol 2013 ◽  
pp. 1-9 ◽  
Author(s):  
Chadlia Hamdi ◽  
Jihène Essanaa ◽  
Luigi Sansonno ◽  
Elena Crotti ◽  
Khaoula Abdi ◽  
...  

Paenibacillus larvaeis the causative agent of American foulbrood (AFB), a virulent disease of honeybee (Apis mellifera) larvae. In Tunisia, AFB has been detected in many beekeeping areas, where it causes important economic losses, but nothing is known about the diversity of the causing agent. Seventy-five isolates ofP. larvae, identified by biochemical tests and 16S rRNA gene sequencing, were obtained from fifteen contaminated broods showing typical AFB symptoms, collected in different locations in the northern part of the country. Using BOX-PCR, a distinct profile ofP. larvaewith respect to relatedPaenibacillusspecies was detected which may be useful for its identification. SomeP. larvae-specific bands represented novel potential molecular markers for the species. BOX-PCR fingerprints indicated a relatively high intraspecific diversity among the isolates not described previously with several molecular polymorphisms identifying six genotypes on polyacrylamide gel. Polymorphisms were also detected in several biochemical characters (indol production, nitrate reduction, and methyl red and oxidase tests). Contrary to the relatively high intraspecies molecular and phenotypic diversity, thein vivovirulence of three selectedP. larvaegenotypes did not differ significantly, suggesting that the genotypic/phenotypic differences are neutral or related to ecological aspects other than virulence.


2017 ◽  
Vol 64 (4) ◽  
Author(s):  
Arathi Dharmaratnam ◽  
Raj Kumar ◽  
V. S. Basheer ◽  
Neeraj Sood ◽  
T. Raja Swaminathan ◽  
...  

Pathogenic strain of Serratia marcescens (NPSM-1) with multiple drug resistance was isolated from guppy Poecilia reticulata with clinical signs of fin rot and was confirmed by biochemical tests and 16S rRNA gene sequencing. The extra cellular proteins (ECP) of the bacteria exhibited marked cytotoxic activity in vitro on Cyprinus carpio koi fin (CCKF) cell line. The in vivo challenge studies confirmed that the isolate was highly pathogenic to fish when the fishes were injected with1 x 104 CFU/fish and the same bacterium was re-isolated from infected fish, post-challenge. S. marcescens produced large zones of haemolysis on 10% sheep blood agar. The bacteria was found to carry virulence genes; extracellular metalloprotease gene (Pr596) and AHL synthase gene (SpnI). The bacterial isolate was tested to determine sensitivity against 16 antibiotics and was sensitive to only 5 viz., cefixime, chloramphenicol, ciprofloxacin, gentamycin and erythromycin. The study indicates that S. marcescens can cause disease in ornamental fish and the bacterium being a known human pathogen, may also cause infections in humans having direct contact with infected fishes. This is the first report describing S. marcescens as a pathogen of freshwater ornamental fish in India.


Author(s):  
Ali Arkan Majhool ◽  
Hamidah Idris ◽  
Wan Mohd Nuzul Hakimi ◽  
Muhd Danish Daniel Abdullah

The existing study examined three actinomycetes isolated from Beach Ridges Interspersed with Swales (BRIS) soil where the morphological properties were examined and chemical compounds of their metabolite extracts were ana; ysed. Based on phylogenetic analysis of 16S rRNA gene sequences, the strains were identified as Streptomyces sp. AA13, Amycolatopsis sp. AA12 and Micromonosporasp. AA141. Antimicrobial activities of the extracts were tested against a panel of microorganisms that consist of Escherichia coli DSM 30083, Bacillus subtilis DSM 10, Pseudomonas fluorescens DSM 50090, Klebsiella pneumoniae DSM 30104, Micrococcus luteus DSM 20030, and Saccharomyces cerevisiae. Results revealed a wide range of antimicrobial activities produced by the isolates at different concentration of each extracts. The extracts were found to show stronger antimicrobial activities against gram-negative bacteria compared to gram-positive bacteria, while no activities were shown when tested against fungi. Thirty-nine compounds were detected both from Streptomycessp. AA13 and Amycolatopsissp. AA12, while thirty-eight compounds from Micromonosporasp. AA141 using GC-MS. This Study Demonstrate the ability of actinomycetes in producing variety type of compounds with antimicrobial activities that may be the potential candidates as drug leads.


1999 ◽  
Vol 43 (5) ◽  
pp. 1077-1084 ◽  
Author(s):  
Masahiro Takahata ◽  
Junichi Mitsuyama ◽  
Yoshiko Yamashiro ◽  
Minoru Yonezawa ◽  
Harumi Araki ◽  
...  

ABSTRACT The in vitro and in vivo activities of T-3811ME, a novel des-F(6)-quinolone, were evaluated in comparison with those of some fluoroquinolones, including a newly developed one, trovafloxacin. T-3811, a free base of T-3811ME, showed a wide range of antimicrobial spectra, including activities against Chlamydia trachomatis, Mycoplasma pneumoniae, andMycobacterium tuberculosis. In particular, T-3811 exhibited potent activity against various gram-positive cocci, with MICs at which 90% of the isolates are inhibited (MIC90s) of 0.025 to 6.25 μg/ml. T-3811 was the most active agent against methicillin-resistant Staphylococcus aureus and streptococci, including penicillin-resistant Streptococcus pneumoniae (PRSP). T-3811 also showed potent activity against quinolone-resistant gram-positive cocci with GyrA and ParC (GrlA) mutations. The activity of T-3811 against members of the familyEnterobacteriaceae and nonfermentative gram-negative rods was comparable to that of trovafloxacin. In common with other fluoroquinolones, T-3811 was highly active against Haemophilus influenzae, Moraxella catarrhalis, andLegionella sp., with MIC90s of 0.0125 to 0.1 μg/ml. T-3811 showed a potent activity against anaerobic bacteria, such as Bacteroides fragilis and Clostridium difficile. T-3811 was the most active agent against C. trachomatis (MIC, 0.008 μg/ml) and M. pneumoniae(MIC90, 0.0313 μg/ml). The activity of T-3811 againstM. tuberculosis (MIC90, 0.0625 μg/ml) was potent and superior to that of trovafloxacin. In experimental systemic infection with a GrlA mutant of S. aureus and experimental pneumonia with PRSP in mice, T-3811ME showed excellent therapeutic efficacy in oral and subcutaneous administrations.


2018 ◽  
Author(s):  
Fatima Muccee ◽  
Samina Ejaz

AbstractThe focus of present study was to isolate and characterize bacteria which can be effectively used for toluene, a highly recalcitrant pollutant, bioremediation. For isolation of bacteria from the tannery effluents selective enrichment and serial dilution methods were employed. The isolated bacteria were subjected to growth curve analysis, estimation of toluene removal efficiencies, biochemical tests, antibiotic sensitivity assays and molecular characterization based upon 16S rRNA gene. The rRNA genes sequences were analyzed through BLAST to determine similarity index of isolates with bacterial database sequences. To trace the evolutionary history, phylogenetic trees were constructed using MEGA version 7. Total twenty toluene metabolizing bacteria (IUBT1-2, 4-12, 16, 19, 21, 23-26, 28 and 30) were isolated and characterized. Their rRNA gene sequences have been submitted to Genbank. Fifteen of the twenty isolates showed homology toBrevibacillus agristrain NBRC 15538, four found similar toBacillus paralicheniformisstrain KJ-16 and one homologous toBurkholderia latastrain 383. All bacterial isolates were resistant to chloramphenicol but sensitive to teicoplanin and linezolid. However, few (i. e.; IUBT9 and 26) were sensitive to oxacillin. Biochemical characterization indicated all bacteria positive for alkaline phosphatases (100%). While many were found positive for p-nitrophenyl N-acetyl β, D-glucosaminidase (35%), hydroxyproline β-naphthylaminopeptidase (15%), esculinase (65%), mannitol (75%), sorbitol (95%) and inulin (90%) fermentation. Biochemical profile suggests the use of isolated bacteria for future exploitation in several fields like bioremediation of toluene, ethanol production, biomass hydrolysis, biosensors, biofertilizers, as a marker for milk pasteurization in dairy industries and evaluation of soil quality.ImportanceToluene is a highly toxic environmental pollutant. We have isolated bacteria which can be effectively used for the removal of toluene from environmental resources. Moreover, these bacteria are capable to produce many valuable enzymes which can be used in many industrial processes for the production of a wide range of products. Further study may help to exploit these bacterial for the benefit of humanity.


Nanomedicine ◽  
2022 ◽  
Author(s):  
Jiří Trousil ◽  
Jana Matějková ◽  
You-Shan Dai ◽  
Tomáš Urbánek ◽  
Miroslav Šlouf ◽  
...  

Background: Antimicrobial submicrometer particles are being studied as promising interventions against a wide range of skin conditions, such as fungal or bacterial infections. Aims: To submicronize chloroxine, the crystalline compound 5,7-dichloro-8-hydroxyquinoline, by nanoprecipitation and characterize the resulting assemblies. Methods: The chloroxine particles were stabilized by a nonionic surfactant and were studied by a broth microdilution assay against 20 medically important bacteria and fungi. The intervention was studied using a murine model of skin irritation. Results & conclusions: Chloroxine nanoparticles with a diameter of 600–800 nm exhibit good tolerability in terms of skin irritation in vivo and good antimicrobial activity. Thus, the fabricated formulation shows great promise for interventions for both cutaneous infection control and prophylaxis.


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