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1.
Biomed Res Int ; 2021: 6626249, 2021.
Artículo en Inglés | MEDLINE | ID: mdl-33997030

RESUMEN

In recent years, certain Lactobacillus sp. have emerged in health care as an alternative therapy for various diseases. Based on this, this study is aimed at evaluating in vitro the potential probiotics of five lactobacilli strains isolated from pulp of cupuaçu fruit fermentation against Gardnerella vaginalis and Neisseria gonorrhoeae. Our lactobacilli strains were classified as safe for use in humans, and they were tolerant to heat and pH. Our strains were biofilm producers, while hydrophobicity and autoaggregation varied from 13% to 86% and 13% to 25%, respectively. The coaggregation of lactobacilli used in this study with G. vaginalis and N. gonorrhoeae ranged from 15% to 36% and 32% to 52%, respectively. Antimicrobial activity was present in all tested Lactobacillus strains against both pathogens, and the growth of pathogens in coculture was reduced by the presence of our lactobacilli. Also, all tested lactobacilli reduced the pH of the culture, even in incubation with pathogens after 24 hours. The cell-free culture supernatants (CFCS) of all five lactobacilli demonstrated activity against the two pathogens with a halo presence and CFCS characterization assay together with gas chromatography revealed that lactic acid was the most abundant organic acid in the samples (50% to 62%). Our results demonstrated that the organic acid production profile is strain-specific. This study revealed that cupuaçu is a promising source of microorganisms with probiotic properties against genital pathogens. We demonstrated by in vitro tests that our Lactobacillus strains have probiotic properties. However, the absence of in vivo tests is a limitation of our work due to the need to evaluate the interaction of our lactobacilli with pathogens in the vaginal mucosa. We believe that these findings may be useful in developing a product containing our lactobacilli and their supernatants in order to support with vaginal health.


Asunto(s)
Cacao/microbiología , Gardnerella vaginalis/efectos de los fármacos , Lactobacillus , Neisseria gonorrhoeae/efectos de los fármacos , Probióticos/farmacología , Antibacterianos/farmacología , Biopelículas/efectos de los fármacos , Frutas/microbiología , Lactobacillus/citología , Lactobacillus/fisiología
2.
J Microbiol Methods ; 177: 106031, 2020 10.
Artículo en Inglés | MEDLINE | ID: mdl-32805365

RESUMEN

The demands for a variety of craft beer flavors have been increasing in the United States. To meet this rising demand, breweries have been experimenting with kettle sour beer that utilizes lactic acid-producing bacteria for fermentation. The current standard bacterial quantification method is insufficient for rigorous quality control, thus there is a need for a better method to monitor lactobacilli concentration in a kettle sour environment. In this work, an automated Lactobacillus counting method was developed using fluorescence-based image cytometry. Three commonly used species were cultured, the concentrations were measured using image cytometry and evaluated against the standard spread-plating method. This procedure was undertaken in vitro at different dilutions and the method was repeated with two species in a kettle sour environment at different time points. Both the in vitro and fermentation experiments were repeated three times. Results demonstrated that the new method was not significantly different when compared to the standard plating method in either controlled settings or within the kettle sour fermentation. The proposed method provides a rapid tool to monitor and control lactobacilli growth in kettle sour beer production, and allows for standardization of the products due to the availability of near instantaneous information for quality control.


Asunto(s)
Técnicas Bacteriológicas/métodos , Cerveza/microbiología , Citometría de Imagen/métodos , Lactobacillus/citología , Bacterias , Cerveza/análisis , Fermentación , Colorantes Fluorescentes , Microbiología de Alimentos/métodos , Ácido Láctico , Lactobacillus/metabolismo , Coloración y Etiquetado/métodos , Gusto
3.
Bull Exp Biol Med ; 168(5): 662-664, 2020 Mar.
Artículo en Inglés | MEDLINE | ID: mdl-32246369

RESUMEN

Adaptive behavior of lactobacilli in cultured in microchambers of different design was analyzed under a light microscope. We found that the time of appearance of first-generation cells for the studied strains of lactobacilli differed in chambers with different rheological properties (stationary and flow-through). The results of our experiments suggest that the development of populations of lactobacilli is regulated by autometabolites of different physiological modalities directly from the very first cell generations. Populations of lactobacilli are under the control of autometabolites at the initial stages of interaction with the environment under various rheological conditions. Rheological conditions of the culture medium of the first generation cells determine the development of cells of the second and probably further cell generations under the same culturing conditions.


Asunto(s)
Adaptación Biológica/fisiología , Técnicas Bacteriológicas , Medios de Cultivo/química , Lactobacillus/fisiología , Reología , Técnicas Bacteriológicas/instrumentación , Técnicas Bacteriológicas/métodos , Reactores Biológicos/microbiología , División Celular/efectos de los fármacos , Medios de Cultivo/farmacología , Ambiente , Lactobacillus/citología , Lactobacillus/crecimiento & desarrollo , Microtecnología/métodos , Reología/instrumentación , Reología/métodos , Factores de Tiempo
4.
Anaerobe ; 62: 102103, 2020 Apr.
Artículo en Inglés | MEDLINE | ID: mdl-31525452

RESUMEN

Screening for probiotic characteristics is usually associated with a series of assays and a large number of isolates to be tested, which can be sometimes costly and frustrating. For this reason, finding some indicators to predict the probiotic potential would be of great significance. In this study, 10 Lactobacillus strains including L. sakei, L. reuteri, L. delbrueckii subsp. lactis, L. delbrueckii subsp. delbrueckii, L. plantarum, L. acidophilus, L. rhamnosus, L. paracasei, L. salivarius, and L. gasseri were characterized by cell morphology and growth properties. The strains were then examined in terms of some probiotic characteristics including resistance to acid and bile conditions, ability to adhesion to intestinal epithelial cells, antioxidant activity, aggregation characteristics, antibacterial activity, hemolytic activity, and resistance to different antibiotics. Correlations between different quantitative features were analyzed using Pearson's coefficient (r). Results of this study provided first-time evidence for the effects of cell length on probiotic features. Based on statistical analysis, long Lactobacillus strains had often higher antioxidant and aggregation activities. Moreover, these long strains were usually more sensitive to acid and bile conditions and resulted in a lower CFU yield compared to short strains. By conducting morphological tests at the first step of screening, some strains would gain higher priority because of predicting a high performance in some of the desired characteristics. Therefore, the cost and time required for the subsequent tests would be significantly reduced.


Asunto(s)
Lactobacillus/citología , Probióticos , Antibacterianos/farmacología , Antibiosis , Antioxidantes/metabolismo , Adhesión Bacteriana , Ácidos y Sales Biliares/farmacología , Línea Celular , Hemólisis , Humanos , Lactobacillus/efectos de los fármacos , Lactobacillus/fisiología , Microscopía
5.
Prep Biochem Biotechnol ; 49(9): 884-890, 2019.
Artículo en Inglés | MEDLINE | ID: mdl-31259668

RESUMEN

Whole cell applications are one of the main methodologies for the bioreduction of prochiral ketones to obtain enantiomerically rich chiral secondary alcohols which are mainly affected by the culture parameters of the whole cell. In this study, whole cell of Lactobacillus senmaizukei as a safe Lactic Acid Bacteria (LAB) was used for the reduction of acetophenone and Response Surface Methodology (RSM) application was used to optimize the culture parameters in terms of temperature, pH, incubation time, and agitation level to obtain the highest enantiomeric excess (ee) and conversion rate. The predicted optimum conditions for the bioreduction with whole cell Lactobacillus senmaizukei were found to be pH of 5.25, temperature of 25 °C, incubation time of 72 hr, and agitation level of 100 rpm. Importantly, the efficiency of the reduction of the acetophenone was significantly affected by the linear and quadratic effects of culture parameters. These findings are important to show the role of culture parameters for the bioreduction reactions and also the efficiency of the RSM technique to optimize these parameters.


Asunto(s)
Acetofenonas/metabolismo , Lactobacillus/metabolismo , Alcoholes/metabolismo , Biocatálisis , Concentración de Iones de Hidrógeno , Microbiología Industrial , Lactobacillus/citología , Oxidación-Reducción , Temperatura
6.
Int J Mol Sci ; 20(10)2019 May 23.
Artículo en Inglés | MEDLINE | ID: mdl-31126033

RESUMEN

Nowadays, the oral use of probiotics is widespread. However, the safety profile with the use of live probiotics is still a matter of debate. Main risks include: Cases of systemic infections due to translocation, particularly in vulnerable patients and pediatric populations; acquisition of antibiotic resistance genes; or interference with gut colonization in neonates. To avoid these risks, there is an increasing interest in non-viable microorganisms or microbial cell extracts to be used as probiotics, mainly heat-killed (including tyndallized) probiotic bacteria (lactic acid bacteria and bifidobacteria). Heat-treated probiotic cells, cell-free supernatants, and purified key components are able to confer beneficial effects, mainly immunomodulatory effects, protection against enteropathogens, and maintenance of intestinal barrier integrity. At the clinical level, products containing tyndallized probiotic strains have had a role in gastrointestinal diseases, including bloating and infantile coli-in combination with mucosal protectors-and diarrhea. Heat-inactivated probiotics could also have a role in the management of dermatological or respiratory allergic diseases. The reviewed data indicate that heat-killed bacteria or their fractions or purified components have key probiotic effects, with advantages versus live probiotics (mainly their safety profile), positioning them as interesting strategies for the management of common prevalent conditions in a wide variety of patients´ characteristics.


Asunto(s)
Bifidobacterium/citología , Lactobacillus/citología , Probióticos/uso terapéutico , Animales , Infecciones Bacterianas/microbiología , Infecciones Bacterianas/terapia , Enfermedades Gastrointestinales/microbiología , Enfermedades Gastrointestinales/terapia , Calor , Humanos , Inmunomodulación , Viabilidad Microbiana , Probióticos/efectos adversos
7.
Int J Biol Macromol ; 133: 987-997, 2019 Jul 15.
Artículo en Inglés | MEDLINE | ID: mdl-31029624

RESUMEN

This study investigates the purification and biochemical characteristics of the protease secreted by Lactobacillus curvatus R5, which was isolated from Harbin dry sausages. The optimized fermentation conditions were fermentation time 36 h, initial pH 6 and fermentation temperature 37 °C. An extracellular protease was purified using ammonium sulfate precipitation, ion-exchange layer and gel filtration. Sodium dodecyl sulphate-polyacrylamide gel electrophoresis (SDS-PAGE) analysis showed that molecular weight of the purified protease was 45.3 kDa. Protease produced by L. curvatus R5 reached a higher relative protease activity at pH 6, 40 °C, and the purified protease exhibited pH and thermal stability at pH 6 and 40 °C. The microbial protease activity can be inhibited by ethylene diamine tetraacetic acid disodium salt (EDTA). The Vmax and Km of the protease were 53 mg/min and 15.9 mg/mL, respectively. SDS-PAGE reflects the ability of the protease to hydrolyse myofibrillar protein and sarcoplasmic protein, especially on myosin heavy chain, actin, myosin light chain and phosphorylase. The 3D structure and the Ramachandran plot of L. curvatus R5 protease was obtained by homology modelling. The Ramachandran plot analysis revealed that the purified protease was composed of 366 amino acids, and its residues in favoured, allowed, generously allowed and disallowed regions were 84.6%, 11.3%, 3.2% and 0.9% residues, respectively. Molecular docking showed that the substrate actin bound to the protease active site by hydrogen bonding and hydrophobic interaction. This research provides a basis for understanding the enzymatic properties of L. curvatus R5 protease. In conclusion, L. curvatus R5 can be used as a starter culture or protease-producing strain to inoculate Harbin dry sausages.


Asunto(s)
Espacio Extracelular/enzimología , Lactobacillus/citología , Productos de la Carne/microbiología , Péptido Hidrolasas/aislamiento & purificación , Péptido Hidrolasas/metabolismo , Dominio Catalítico , Estabilidad de Enzimas , Fermentación , Concentración de Iones de Hidrógeno , Hidrólisis , Lactobacillus/aislamiento & purificación , Lactobacillus/metabolismo , Simulación del Acoplamiento Molecular , Miofibrillas/metabolismo , Péptido Hidrolasas/química , Temperatura
8.
Parasitol Res ; 118(2): 693-699, 2019 Feb.
Artículo en Inglés | MEDLINE | ID: mdl-30623233

RESUMEN

Chinese liver fluke Clonorchis sinensis changes the host's immune system. Recently, it has been reported that helminths including C. sinensis can ameliorate immune-related diseases such as allergy. In addition, recent studies showed that helminth infection can alleviate immune-mediated disorders by altering the gut microbiome. However, changes in the gut microbiome due to C. sinensis have not been reported yet. In this study, changes in the gut microbiome of C57BL/6 mice infected with C. sinensis metacercariae were evaluated over time. Stool was analyzed by 16S rRNA amplicon analysis using high-throughput sequencing technology. There was no apparent difference in species richness and diversity between the infected and control groups. However, the composition of the microbiome was different between the infected and control groups at 20 days and 30 days post-infection, and the difference disappeared at 50 days post-infection. In particular, this microbiome alteration was associated with a change in the relative abundance of genus Lactobacillus and the probiotic Lactobacillus species that are known to have an immune-modulation role in immune-mediated diseases.


Asunto(s)
Clonorquiasis/inmunología , Clonorchis sinensis/inmunología , Microbioma Gastrointestinal/fisiología , Lactobacillus/crecimiento & desarrollo , Probióticos/análisis , Animales , Clonorquiasis/parasitología , Clonorchis sinensis/crecimiento & desarrollo , Heces/microbiología , Secuenciación de Nucleótidos de Alto Rendimiento , Lactobacillus/clasificación , Lactobacillus/citología , Metacercarias/citología , Ratones , Ratones Endogámicos C57BL , ARN Ribosómico 16S/genética
9.
Allergy ; 74(1): 100-110, 2019 01.
Artículo en Inglés | MEDLINE | ID: mdl-29888398

RESUMEN

BACKGROUND: There is an increasing interest in targeted application of probiotic bacteria for prevention and treatment of airway diseases, including allergies. Here, we investigated the beneficial effects of preventive intranasal treatment with probiotics Lactobacillus rhamnosus GG and L. rhamnosus GR-1 in a mouse model of allergic asthma. METHODS: Lactobacillus rhamnosus was administered intranasally eight times on days 1-4 and 8-11 at 5 × 108  CFU/dose, followed by a 2-week asthma induction protocol with birch pollen extract on alternating days. Effects of preventive treatment were analyzed based on serum antibody levels, bronchoalveolar lavage cell counts, lung histology, lung cytokine levels, and airway hyperreactivity. Colonization and translocation of L. rhamnosus were assessed by bacterial cell counts in nasal mucosa, fecal samples, cervical lymph nodes, and blood. Binding of fluorescent L. rhamnosus to fixed murine nasal mucosal cells and airway macrophages was visualized by fluorescence microscopy. RESULTS: Transient colonization of the murine upper airways by L. rhamnosus GG was demonstrated and was approximately ten times higher compared to L. rhamnosus GR-1. Marked binding of fluorescent L. rhamnosus GG to murine nasal mucosal cells and airway macrophages was visualized. Preventive treatment with L. rhamnosus GG (but not L. rhamnosus GR-1) resulted in a significant decrease in bronchoalveolar lavage eosinophil counts, lung interleukin-13 and interleukin-5 levels, and airway hyperreactivity. A tendency toward a decrease in serum Bet v 1-specific immunoglobulin G1 was likewise observed. CONCLUSION: Intranasally administered L. rhamnosus GG prevents the development of cardinal features of birch pollen-induced allergic asthma in a strain-specific manner.


Asunto(s)
Asma/prevención & control , Lactobacillus/citología , Probióticos/uso terapéutico , Administración Intranasal , Animales , Asma/inmunología , Adhesión Bacteriana , Betula/inmunología , Modelos Animales de Enfermedad , Macrófagos Alveolares/metabolismo , Ratones , Mucosa Nasal/metabolismo , Polen/inmunología , Especificidad de la Especie
10.
PLoS One ; 13(7): e0201003, 2018.
Artículo en Inglés | MEDLINE | ID: mdl-30036385

RESUMEN

BACKGROUND: Hormonal contraception has been associated with a reduced risk of vaginal dysbiosis, which in turn has been associated with reduced prevalence of sexually transmitted infections (STIs), including HIV. Vaginal rings are used or developed as delivery systems for contraceptive hormones and antimicrobial drugs for STI and HIV prevention or treatment. We hypothesized that a contraceptive vaginal ring (CVR) containing oestrogen enhances a lactobacilli-dominated vaginal microbial community despite biomass accumulation on the CVR's surface. METHODS: We enrolled 120 women for 12 weeks in an open-label NuvaRing® study at Rinda Ubuzima, Kigali, Rwanda. Vaginal and ring microbiota were assessed at baseline and each ring removal visit by Gram stain Nugent scoring (vaginal only), quantitative PCR for Lactobacillus species, Gardnerella vaginalis and Atopobium vaginae, and fluorescent in situ hybridization to visualize cell-adherent bacteria. Ring biomass was measured by crystal violet staining. RESULTS: Bacterial vaginosis (BV) prevalence was 48% at baseline. The mean Nugent score decreased significantly with ring use. The presence and mean log10 concentrations of Lactobacillus species in vaginal secretions increased significantly whereas those of G. vaginalis and presence of A. vaginae decreased significantly. Biomass accumulated on the CVRs with a species composition mirroring the vaginal microbiota. This ring biomass composition and optical density after crystal violet staining did not change significantly over time. CONCLUSIONS: NuvaRing® promoted lactobacilli-dominated vaginal microbial communities in a population with high baseline BV prevalence despite the fact that biomass accumulated on the rings.


Asunto(s)
Dispositivos Anticonceptivos Femeninos/efectos adversos , Dispositivos Anticonceptivos Femeninos/microbiología , Lactobacillus/fisiología , Vagina/microbiología , Vaginosis Bacteriana/epidemiología , Vaginosis Bacteriana/etiología , Adulto , Biomasa , Células Epiteliales/citología , Femenino , Humanos , Lactobacillus/citología , Lactobacillus/efectos de los fármacos , Estudios Longitudinales , Prevalencia , Rwanda , Vagina/citología , Vagina/efectos de los fármacos
11.
Nature ; 557(7706): 580-584, 2018 05.
Artículo en Inglés | MEDLINE | ID: mdl-29769727

RESUMEN

Somatic mutations in tet methylcytosine dioxygenase 2 (TET2), which encodes an epigenetic modifier enzyme, drive the development of haematopoietic malignancies1-7. In both humans and mice, TET2 deficiency leads to increased self-renewal of haematopoietic stem cells with a net developmental bias towards the myeloid lineage1,4,8,9. However, pre-leukaemic myeloproliferation (PMP) occurs in only a fraction of Tet2-/- mice8,9 and humans with TET2 mutations1,3,5-7, suggesting that extrinsic non-cell-autonomous factors are required for disease onset. Here we show that bacterial translocation and increased interleukin-6 production, resulting from dysfunction of the small-intestinal barrier, are critical for the development of PMP in mice that lack Tet2 expression in haematopoietic cells. Furthermore, in symptom-free Tet2-/- mice, PMP can be induced by disrupting intestinal barrier integrity, or in response to systemic bacterial stimuli such as the toll-like receptor 2 agonist. PMP was reversed by antibiotic treatment and failed to develop in germ-free Tet2-/- mice, which illustrates the importance of microbial signals in the development of this condition. Our findings demonstrate the requirement for microbial-dependent inflammation in the development of PMP and provide a mechanistic basis for the variation in PMP penetrance observed in Tet2-/- mice. This study will prompt new lines of investigation that may profoundly affect the prevention and management of haematopoietic malignancies.


Asunto(s)
Enfermedades Asintomáticas , Fenómenos Fisiológicos Bacterianos , Proliferación Celular , Proteínas de Unión al ADN/deficiencia , Leucemia/microbiología , Leucemia/patología , Proteínas Proto-Oncogénicas/deficiencia , Animales , Infecciones Bacterianas/inmunología , Infecciones Bacterianas/microbiología , Fenómenos Fisiológicos Bacterianos/inmunología , Proteínas de Unión al ADN/genética , Dioxigenasas , Femenino , Vida Libre de Gérmenes , Inflamación/microbiología , Interleucina-6/inmunología , Mucosa Intestinal/metabolismo , Lactobacillus/química , Lactobacillus/citología , Lactobacillus/inmunología , Masculino , Ratones , Penetrancia , Permeabilidad , Proteínas Proto-Oncogénicas/genética , Receptor Toll-Like 2/agonistas
12.
J Biosci Bioeng ; 125(5): 513-518, 2018 May.
Artículo en Inglés | MEDLINE | ID: mdl-29331529

RESUMEN

For the industrial production of probiotics powder, various sugars have been used as cryoprotectants to preserve probiotics during freeze-drying. Some of these sugars can be metabolized by Lactobacillus with the production of acids during the mix. In this study, we investigated the effect of acids on ATPase, ß-galactosidase, lactate dehydrogenase (LDH), integrity and fluidity of cell membrane and the survival rate of Lactobacillus during freeze-drying. In the presence of Lactobacillus, acids were produced from cryoprotectants containing fermentable sugars before freezing, resulting in a decrease in the pH of the bacterial suspension to below 5.0. During freeze-drying, the acids caused a loss of viability of Lactobacillus due to aggravated damage to ATPase, ß-galactosidase and cell membrane fluidity, but not LDH and cell membrane integrity. This finding implied that cryoprotectants that do not lead to the production of acids are effective in improving the survival rate of freeze-dried Lactobacillus. Here, a new formula was proposed for a protectant containing whey protein isolate (WPI) and rhamnose, which were not metabolized. In addition, linear-regression analyses were performed on the proportion of cryoprotectants (M) against cell paste (m), total cell count (N), total surface area (St) and total volume (Vt) of bacteria for 100% survival rate. The total surface areas of bacteria were found to be highly correlated with the amount of proposed cryoprotectant. The following prediction equation was established for the optimal initial cell concentration for a 100% survival rate of freeze-dried Lactobacillus: N (4πr2+2πl)=(0.66±0.03)M.


Asunto(s)
Ácidos/farmacología , Metabolismo de los Hidratos de Carbono/efectos de los fármacos , Crioprotectores/farmacología , Lactobacillus/efectos de los fármacos , Lactobacillus/metabolismo , Viabilidad Microbiana/efectos de los fármacos , Preservación Biológica , Ácidos/metabolismo , Carga Bacteriana/normas , Membrana Celular/efectos de los fármacos , Crioprotectores/química , Fermentación , Liofilización/normas , Lactobacillus/citología , Preservación Biológica/métodos , Preservación Biológica/normas , Probióticos/normas
13.
Obes Facts ; 10(5): 473-482, 2017.
Artículo en Inglés | MEDLINE | ID: mdl-29020671

RESUMEN

BACKGROUND: Recent studies have shown an association between weight change and the makeup of the intestinal microbiota in humans. Specifically, Lactobacillus, a part of the entire gastrointestinal tract's microbiota, has been shown to contribute to weight regulation. AIM: We examined the association between the level of oral Lactobacillus and the subsequent 6-year weight change in a healthy population of 322 Danish adults aged 35-65 years at baseline. DESIGN: Prospective observational study. RESULTS: In unadjusted analysis the level of oral Lactobacillus was inversely associated with subsequent 6-year change in BMI. A statistically significant interaction between the baseline level of oral Lactobacillus and the consumption of complex carbohydrates was found, e.g. high oral Lactobacillus count predicted weight loss for those with a low intake of complex carbohydrates, while a medium intake of complex carbohydrates predicted diminished weight gain. A closer examination of these relations showed that BMI change and Lactobacillus level was unrelated for those with high complex carbohydrate consumption. CONCLUSION: A high level of oral Lactobacillus seems related to weight loss among those with medium and low intakes of complex carbohydrates. Absence, or a low level of oral Lactobacillus, may potentially be a novel marker to identify those at increased risk of weight gain.


Asunto(s)
Susceptibilidad a Enfermedades/microbiología , Microbioma Gastrointestinal/fisiología , Lactobacillus/citología , Boca/microbiología , Obesidad/diagnóstico , Obesidad/microbiología , Aumento de Peso , Adulto , Anciano , Carga Bacteriana , Dinamarca , Femenino , Estudios de Seguimiento , Tracto Gastrointestinal/microbiología , Humanos , Masculino , Persona de Mediana Edad , Sobrepeso/diagnóstico , Sobrepeso/microbiología , Pronóstico
14.
FEMS Microbiol Lett ; 364(3)2017 02 01.
Artículo en Inglés | MEDLINE | ID: mdl-28087614

RESUMEN

In this study, the potential of Fourier transform infrared (FTIR) spectroscopy for assessing putative biochemical and structural differences between the two variants, rough (R) and smooth (S), of Lactobacillus farciminis CNCM-I-3699, a pleomorphic strain, was investigated. The main differences observed were localized in the polysaccharide (1200-900 cm-1) and protein (1700-1500 cm-1) regions. Based on spectral information in these two spectral ranges, clustering resulted in a dendrogram that showed a clear discrimination between both morphotypes. Significant increases in favor of morphotype S compared to R at specific wavenumbers for polysaccharides (22.18% vs. 5.24% at 1068 cm-1) and capsular polysaccharides (16% vs. 13.17% at 1048 cm-1) were recorded. Compared to S, the morphotype R exhibits a 1.27-fold higher signal at the wavenumber of 1637 cm-1 assigned to the amide I ß-sheet and a 2.71-fold higher signal at the wavenumber of 1513 cm-1 assigned to the tyrosine involved in the ß-sheet arrangement of proteins. The FTIR analysis is efficient to separate and give data on mainly surface component differences observed previously between S colony morphotype (ropy and exopolysaccharide positive) and the R colony morphotype (non-ropy but highly autoaggregative).


Asunto(s)
Proteínas Bacterianas/análisis , Lactobacillus/química , Polisacáridos Bacterianos/análisis , Espectroscopía Infrarroja por Transformada de Fourier , Lactobacillus/citología
15.
Appl Microbiol Biotechnol ; 101(8): 3415-3425, 2017 Apr.
Artículo en Inglés | MEDLINE | ID: mdl-28004153

RESUMEN

Accumulation of toxic metal ions in food and water is nowadays a growing health-related problem. One detoxification method involves the use of microorganisms naturally inhabiting the gastrointestinal tract (GIT). The purpose of this study was to prove that lactic acid bacteria derived from the GIT are able to effectively remove Cd2+ from water solution. Seven strains of lactobacilli, out of 11 examined, showed tolerance to high concentrations of cadmium ions. The metal-removal efficiencies of these seven lactobacilli ranged from 6 to 138.4 µg/h mg. Among these bacteria, Lactobacillus gallinarum and Lactobacillus crispatus belonged to the highest (85%) Cd-removal efficiency class. An analysis of the zeta potential (ζ) indicated that the bacterial cell surface had a negative charge at the pH ranging from 3 to 10. The presence of carboxyl, amide, and phosphate groups was favorable for Cd2+ binding to the cell surface, which found confirmation in FTIR-ATR spectra. Elemental SEM/EDS analysis and TEM imaging not only confirmed the adsorption of Cd2+ on the cell envelope but also gave us a reason to suppose that Lb. crispatus accumulates metal ions inside the cell. Our findings open perspectives for further research on the new biological function of GIT lactobacilli as natural biosorbents.


Asunto(s)
Cadmio/metabolismo , Tracto Gastrointestinal/microbiología , Lactobacillus/efectos de los fármacos , Lactobacillus/metabolismo , Contaminantes Químicos del Agua/metabolismo , Adsorción , Cadmio/farmacología , Concentración de Iones de Hidrógeno , Iones , Lactobacillus/citología , Microscopía Electrónica de Transmisión , Contaminantes Químicos del Agua/farmacología
16.
Methods Mol Biol ; 1479: 273-279, 2017.
Artículo en Inglés | MEDLINE | ID: mdl-27738944

RESUMEN

Probiotics are dietary concepts to improve the dynamics of intestinal microbial balance favorably. Careful screening of probiotic strains for their technological suitability can also allow selection of strains with the best manufacturing and food technology characteristics. However, even the most robust probiotic bacteria are currently in the range of food applications to which they can be applied. Additionally, bacteria with exceptional functional heath properties are ruled out due to technological limitations. New process and formulation technologies will enable both expansion of the range of products in to which probiotics can be applied and the use of efficacious stains that currently cannot be manufactured or stored with existing technologies. Viability of probiotics has been both a marketing and technological concern for many industrial produces. Probiotics are difficult to work with, the bacteria often die during processing, and shelf life is unpredictable. Probiotics are extremely susceptible environmental conditions such as oxygen, processing and preservation treatments, acidity, and salt concentration, which collectively affect the overall viability of probiotics. Manufacturers have long been fortifying products with probiotics; they have faced significant processing challenges regarding the stability and survivability of probiotics during processing and preservation treatments, storage as well during their passage through GIT. Application of microencapsulation significantly improves the stability of probiotics during food processing and gastrointestinal transit.


Asunto(s)
Alginatos/química , Células Inmovilizadas/citología , Emulsiones/química , Lactobacillus/citología , Probióticos/administración & dosificación , Cloruro de Calcio/química , Composición de Medicamentos/métodos , Ácido Glucurónico/química , Ácidos Hexurónicos/química , Aceite de Soja/química
17.
BMC Microbiol ; 16: 49, 2016 Mar 22.
Artículo en Inglés | MEDLINE | ID: mdl-27001290

RESUMEN

BACKGROUND: Most lactic acid bacteria are non-motile but some of them are flagellated and exhibit motility. So far, motile lactobacilli have rarely been studied, and characteristics of their flagellins are poorly understood. In this study, a highly motile strain of Lactobacillus agilis was recruited for transcriptional analysis and characterization of its flagellins. RESULTS: Unlike another motile lactic acid bacteria of intestinal isolate, Lactobacillus ruminis, flagellar filaments of the L. agilis strain probably consist of two homologous but distinct flagellins. Glycosylation of the flagellar filaments and their resistance to heat, acid and SDS were also observed. The immunological activity of the flagellins was evaluated through the stimulation of Caco-2 cells. The results show that TLR5-stimulating activity of the protein is attenuated, likely due to an incomplete TLR5-recognition site. CONCLUSIONS: The flagella filaments of L. agilis BKN88 consist of two homologous glycosylated flagellins, which likely have an incomplete TLR5-recognition site. The characteristics of the flagellin are presumably a consequence of adaptation as a commensal microbe in the gastrointestinal tract.


Asunto(s)
Proteínas Bacterianas/metabolismo , Flagelina/metabolismo , Lactobacillus/citología , Lactobacillus/metabolismo , Secuencia de Aminoácidos , Proteínas Bacterianas/química , Proteínas Bacterianas/genética , Flagelina/química , Flagelina/genética , Glicosilación , Humanos , Lactobacillus/genética , Lactobacillus/aislamiento & purificación , Datos de Secuencia Molecular , Alineación de Secuencia
18.
Food Funct ; 7(1): 104-9, 2016 Jan.
Artículo en Inglés | MEDLINE | ID: mdl-26437130

RESUMEN

The dietary modulation of gut microbiota, suggested to be involved in allergy processes, has recently attracted much interest. While several studies have addressed the use of fibres to modify intestinal microbial populations, information about other components, such as phenolic compounds, is scarce. The aim of this work was to identify the dietary components able to influence the microbiota in 23 subjects suffering from rhinitis and allergic asthma, and 22 age- and sex-matched controls. The food intake was recorded by means of an annual food frequency questionnaire. Dietary fibre tables were obtained from Marlett et al., and the Phenol-Explorer database was used to assess the phenolic compound intake. The quantification of microbial groups was performed using an Ion Torrent 16S rRNA gene-based analysis. The results showed a direct association between the intake of red wine, a source of stilbenes, and the relative abundance of Bacteroides, and between the intake of coffee, rich in phenolic acids, and the abundance of Clostridium, Lactococcus and Lactobacillus genera. Despite epidemiological analyses not establishing causality, these results support the association between polyphenol-rich beverages and faecal microbiota in allergic patients.


Asunto(s)
Café/química , Microbioma Gastrointestinal/efectos de los fármacos , Hipersensibilidad/inmunología , Hipersensibilidad/microbiología , Fenoles/administración & dosificación , Vino/análisis , Adulto , Asma/microbiología , Carga Bacteriana , Bacteroides/citología , Bacteroides/efectos de los fármacos , Clostridium/citología , Clostridium/efectos de los fármacos , Dieta , Fibras de la Dieta/administración & dosificación , Heces/microbiología , Femenino , Flavonoides/administración & dosificación , Humanos , Hidroxibenzoatos/administración & dosificación , Lactobacillus/citología , Lactobacillus/efectos de los fármacos , Lactococcus/citología , Lactococcus/efectos de los fármacos , Masculino , Persona de Mediana Edad , Rinitis Alérgica/microbiología , Estilbenos/administración & dosificación
19.
Int J Syst Evol Microbiol ; 66(1): 236-242, 2016 Jan.
Artículo en Inglés | MEDLINE | ID: mdl-26486967

RESUMEN

The analysis of the bacterial microbiota of retain samples of pork salami revealed an isolate (strain TMW 1.2011T) that could neither be assigned to typical genera of starter organisms nor to any other known meat-associated species. Cells were Gram-stain-positive, short, straight rods occurring singly, in pairs or short chains. Phylogenetic analysis of the 16S rRNA gene sequence and specific phenotypic characteristics showed that strain TMW 1.2011T belonged to the phylogenetic Lactobacillus alimentarius group, and the closest neighbours were Lactobacillus nodensis JCM 14932T (97.8 % 16S rRNA gene sequence similarity), Lactobacillus tucceti DSM 20183T (97.4 %), 'Lactobacillus ginsenosidimutans' EMML 3041 (97.3 %), Lactobacillus versmoldensis DSM 14857T (96.9 %) and Lactobacillus furfuricola JCM 18764T (97.2 %). Similarities using partial gene sequences of the alternative chronometers pheS, dnaK and rpoA also support these relationships. DNA-DNA relatedness between the novel isolate and L. nodensis JCM 14932T, L. versmoldensis DSM 14857T and L. tucceti DSM 20183T, L. furfuricola JCM 18764T and 'L. ginsenosidimutans' EMML 3041 were below 70 % and the DNA G+C content was 36.3 mol%. The cell-wall peptidoglycan type is l-Lys-Gly-d-Asp. Based on phylogenetic, chemotaxonomic and physiological evidence, strain TMW 1.2011T represents a novel species of the genus Lactobacillus, for which the name Lactobacillus insicii sp. nov. is proposed. The type strain is TMW 1.2011T ( = CECT 8802T = DSM 29801T).


Asunto(s)
Microbiología de Alimentos , Lactobacillus/citología , Productos de la Carne/microbiología , Filogenia , Animales , Técnicas de Tipificación Bacteriana , Composición de Base , ADN Bacteriano/genética , Dipéptidos/química , Ácidos Grasos/química , Fermentación , Lactobacillus/genética , Lactobacillus/aislamiento & purificación , Datos de Secuencia Molecular , Hibridación de Ácido Nucleico , Peptidoglicano/química , ARN Ribosómico 16S/genética , Análisis de Secuencia de ADN , Porcinos
20.
Klin Lab Diagn ; 60(6): 41-5, 2015 Jun.
Artículo en Ruso | MEDLINE | ID: mdl-26466451

RESUMEN

The article presents analysis of laboratory criteria and classifcations used to interpret results of laboratory analysis by technique of microscopy on bacterial vaginosis or dysbacteriosis of vagina. Their advantages and restrictions are demonstrated The unified criteria of evaluation are proposed concerning results of microscopy of mucosal discharge of vagina and corresponding classification. Thereafter, three degrees of bacterial vaginosis (dysbacteriosis of vagina) are differentiated: first degree--compensated dysbacteriosis of vagina, second degree--sub compensated dysbacteriosis of vagina and third degree--decompensated dysbacteriosis of vagina. The corresponding laboratory report of physician is formulated. The proposals are presented concerning development of common unified requirements to stages (pre-analytical, analytical, post-analytical) of laboratory diagnostic of bacterial vaginosis (dysbacteriosis of vagina) with purpose of their unambiguous understanding by clinicians and hence their decision making concerning necessity and tactics of management of patient.


Asunto(s)
Disbiosis/diagnóstico , Membrana Mucosa/microbiología , Vagina/microbiología , Vaginosis Bacteriana/diagnóstico , Técnicas de Tipificación Bacteriana , Bacteroides/citología , Candida albicans/citología , Candida albicans/patogenicidad , Disbiosis/clasificación , Disbiosis/microbiología , Disbiosis/patología , Femenino , Gardnerella vaginalis/citología , Gardnerella vaginalis/patogenicidad , Humanos , Lactobacillus/citología , Microscopía , Membrana Mucosa/patología , Neisseria gonorrhoeae/citología , Neisseria gonorrhoeae/patogenicidad , Trichomonas vaginalis/citología , Trichomonas vaginalis/patogenicidad , Vagina/patología , Vaginosis Bacteriana/clasificación , Vaginosis Bacteriana/microbiología , Vaginosis Bacteriana/patología
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