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Electron. j. biotechnol ; 51: 67-78, May. 2021. graf, tab
Article in English | LILACS | ID: biblio-1343435


BACKGROUND: Endometritis is the most common disease of dairy cows and traditionally treated with antibiotics. Lactic acid bacteria can inhibit the growth of pathogens and also have potential for treatment of endometritis. Using PacBio single-molecule real-time sequencing technology, we sequenced the fulllength l6S rRNA of the microbiota in uterine mucus samples from 31 cows with endometritis, treated with lactic acid bacteria (experimental [E] group) and antibiotics (control [C] group) separately. Microbiota profiles taken before and after treatment were compared. RESULTS: After both treatments, bacterial species richness was significantly higher than before, but there was no significant difference in bacterial diversity. Abundance of some bacteria increased after both lactic acid bacteria and antibiotic treatment: Lactobacillus helveticus, Lactococcus lactis, Lactococcus raffinolactis, Pseudomonas alcaligenes and Pseudomonas veronii. The bacterial species that significantly decreased in abundance varied depending on whether the cows had been treated with lactic acid bacteria or antibiotics. Abundance of Staphylococcus equorum and Treponema brennaborense increased after lactic acid bacteria treatment but decreased after antibiotic treatment. According to COG-based functional metagenomic predictions, 384 functional proteins were significantly differently expressed after treatment. E and C group protein expression pathways were significantly higher than before treatment (p < 0.05). CONCLUSIONS: In this study, we found that lactic acid bacteria could cure endometritis and restore a normal physiological state, while avoiding the disadvantages of antibiotic treatment, such as the reductions in abundance of beneficial microbiota. This suggests that lactic acid bacteria treatment has potential as an alternative to antibiotics in the treatment of endometritis in cattle.

Animals , Female , Cattle , Cattle Diseases/drug therapy , Endometritis/drug therapy , Lactobacillales/metabolism , High-Throughput Nucleotide Sequencing/methods , Anti-Bacterial Agents/administration & dosage , Bacteria/isolation & purification , Bacteria/growth & development , Bacteria/drug effects , Uterus/microbiology , RNA, Ribosomal, 16S/genetics , Lactic Acid , Lactobacillales/genetics , Microbiota
Electron J Biotechnol ; 49: 34-41, Jan. 2021. tab, graf
Article in English | LILACS | ID: biblio-1291638


BACKGROUND: This work studied how the exposure to an unusual substrate forced a change in microbial populations during anaerobic fermentation of crude glycerol, a by-product of biodiesel production, with freshwater sediment used as an inoculum. RESULTS: The microbial associations almost completely (99.9%) utilized the glycerol contained in crude glycerol 6 g L 1 within four days, releasing gases, organic acids (acetic, butyric) and alcohols (ethanol, n-butanol) under anaerobic conditions. In comparison with control medium without glycerol, adding crude glycerol to the medium increased the amount of ethanol and n-butanol production and it was not significantly affected by incubation temperature (28 C or 37 C), nor incubation time (4 or 8 d), but it resulted in reduced amount of butyric acid. Higher volume of gas was produced at 37 C despite the fact that the overall bacterial count was smaller than the one measured at 20 C. Main microbial phyla of the inoculum were Actinobacteria, Proteobacteria and Firmicutes. During fermentation, significant changes were observed and Firmicutes, especially Clostridium spp., began to dominate, and the number of Actinobacteria and Gammaproteobacteria decreased accordingly. Concentration of Archaea decreased, especially in medium with crude glycerol. These changes were confirmed both by culturing and culture-independent (concentration of 16S rDNA) methods. CONCLUSIONS: Crude glycerol led to the adaptation of freshwater sediment microbial populations to this substrate. Changes of microbial community were a result of a community adaptation to a new source of carbon.

Bacteria/isolation & purification , Geologic Sediments/microbiology , Fresh Water/microbiology , Glycerol/metabolism , Bacteria/metabolism , Adaptation, Biological , Biofuels , Fermentation , Real-Time Polymerase Chain Reaction/methods , Anaerobiosis
Electron. j. biotechnol ; 45: 30-37, May 15, 2020. ilus, graf
Article in Spanish | LILACS | ID: biblio-1177412


BACKGROUND: Traditionally, microbial genome sequencing has been restrained to the species grown in pure culture. The development of culture-independent techniques over the last decade allows scientists to sequence microbial communities directly from environmental samples. Metagenomics is the study of complex genome by the isolation of DNA of the whole community. Next generation sequencing (NGS) of metagenomic DNA gives information about the microbial and taxonomical characterization of a particular niche. The objective of the present research is to study the microbial and taxonomical characterization of the metagenomic DNA, isolated from the frozen soil sample of a glacier in the north western Himalayas through NGS. RESULTS: The glacier community comprised of 16 phyla with the representation of members belonging to Proteobacteria and Acidobacteria. The number of genes annotated through the Kyoto Encyclopedia of Genes and Genomes (KEGG), GO, Pfam, Clusters of Orthologous Groups of proteins (COGs), and FIG databases were generated by COGNIZER. The annotation of genes assigned in each group from the metagenomics data through COG database and the number of genes annotated in different pathways through KEGG database were reported. CONCLUSION: Results indicate that the glacier soil taken in the present study, harbors taxonomically and metabolically diverse communities. The major bacterial group present in the niche is Proteobacteria followed by Acidobacteria, and Actinobacteria, etc. Different genes were annotated through COG and KEGG databases that integrate genomic, chemical, and systemic functional information.

Soil Microbiology , Bacteria/classification , High-Throughput Nucleotide Sequencing , Microbiota/genetics , Bacteria/isolation & purification , Cold Climate , Computational Biology , Ice Cover , Metagenomics , Genome, Microbial , India
Electron. j. biotechnol ; 43: 16-22, Jan. 2020. tab, graf
Article in English | LILACS | ID: biblio-1087512


Background: The intestinal bacterial community has an important role in maintaining human health. Dysbiosis is a key inducer of many chronic diseases including obesity and diabetes. Kunming mice are frequently used as a model of human disease and yet little is known about the bacterial microbiome resident to the gastrointestinal tract. Results: We undertook metagenomic sequencing of the luminal contents of the stomach, duodenum, jejunum, ileum, cecum, colon, and rectum of Kunming mice. Firmicutes was the dominant bacterial phylum of each intestinal tract and Lactobacillus the dominant genus. However, the bacterial composition differed among the seven intestinal tracts of Kunming mice. Compared with the small intestine, the large intestine bacterial community of Kunming mice is more stable and diverse. Conclusions: To our knowledge, ours is the first study to systematically describe the gastrointestinal bacterial composition of Kunming mice. Our findings provide a better understanding of the bacterial composition of Kunming mice and serves as a foundation for the study of precision medicine.

Animals , Mice , Bacteria/isolation & purification , Gastrointestinal Tract/microbiology , Bacteria/genetics , RNA, Ribosomal, 16S , Polymerase Chain Reaction , High-Throughput Nucleotide Sequencing , Firmicutes/isolation & purification , Gastrointestinal Microbiome , Lactobacillus/isolation & purification
Electron. j. biotechnol ; 43: 23-31, Jan. 2020. ilus, graf
Article in English | LILACS | ID: biblio-1087514


Background: Hong Qu glutinous rice wine (HQGRW) is brewed under non-aseptic fermentation conditions, so it usually has a relatively high total acid content. The aim of this study was to investigate the dynamics of the bacterial communities and total acid during the fermentation of HQGRW and elucidate the correlation between total acid and bacterial communities. Results: The results showed that the period of rapid acid increase during fermentation occurred at the early stage of fermentation. There was a negative response between total acid increase and the rate of increase in alcohol during the early fermentation stage. Bacterial community analysis using high-throughput sequencing technology was found that the dominant bacterial communities changed during the traditional fermentation of HQGRW. Both principal component analysis (PCA) and hierarchical clustering analysis revealed that there was a great difference between the bacterial communities of Hong Qu starter and those identified during the fermentation process. Furthermore, the key bacteria likely to be associated with total acid were identified by Spearman's correlation analysis. Lactobacillus, unclassified Lactobacillaceae, and Pediococcus were found, which can make significant contributions to the total acid development (| r| N 0.6 with FDR adjusted P b 0.05), establishing that these bacteria can associate closely with the total acid of rice wine. Conclusions: This was the first study to investigate the correlation between bacterial communities and total acid during the fermentation of HQGRW. These findings may be helpful in the development of a set of fermentation techniques for controlling total acid.

Bacteria/isolation & purification , Wine/microbiology , Pediococcus/isolation & purification , Pediococcus/genetics , Pediococcus/metabolism , Time Factors , Acetobacter/isolation & purification , Acetobacter/genetics , Acetobacter/metabolism , Cluster Analysis , Sequence Analysis , Computational Biology , Principal Component Analysis , Fermentation , Microbiota , Hydrogen-Ion Concentration , Lactobacillus/isolation & purification , Lactobacillus/genetics , Lactobacillus/metabolism
Medwave ; 20(8): e8029, 2020.
Article in Spanish | LILACS | ID: biblio-1128727


INTRODUCCIÓN: La intervención en poblaciones por medio de programas educativos logra aumentar el conocimiento en un determinado grupo y además, en algunos casos, se logra un cambio de conducta. OBJETIVO: Determinar si el programa educativo de lavado de manos aplicado a los estudiantes de educación secundaria reduce la colonización de bacterias infecciosas en las manos. METODOLOGÍA: Se realizó un estudio cuasi experimental no aleatorizado mediante muestreo consecutivo a los alumnos del último año de secundaria, quienes fueron divididos en dos grupos de intervención y control, analizados en dos etapas antes y después de la aplicación del programa educativo. Se tomaron las muestras de la mano dominante para el cultivo bacteriano. Además, se aplicó un cuestionario que evaluó los conocimientos sobre higiene de manos antes y después de la aplicación del programa, que estuvo dirigido a mejorar el nivel de conocimiento y de las actitudes de los estudiantes en relación a la higiene de manos. RESULTADOS: De 208 muestras obtenidas los agentes más frecuentes antes y después de la aplicación del programa educativo fueron Staphylococcus epidermidis (39% versus 23%) y Staphylococcus aureus (21%versus15%); el promedio del número de colonias fue 236 y 183 respectivamente (p = 0,35). CONCLUSIÓN: La aplicación del programa educativo logró mejorar el nivel de conocimiento sobre la higiene de manos. Sin embargo, no fue suficiente para reducir la colonización bacteriana, por lo que debería agregarse otras conductas como la supervisión directa.

INTRODUCTION: Educational interventions can raise awareness and understanding in population groups and may help to achieve changes in behavior. OBJECTIVE: To determine if the educational handwashing program applied to high-school students reduces the colonization of infectious bacteria on the hands. METHODS: A non-randomized quasi-experimental study was carried out using consecutive sampling of the students of the last year of high-school who were divided into an intervention group and a control group. Data were obtained before and after the implementation of the educational program. Samples were taken from the dominant hand for bacterial culture, and a questionnaire was applied that assessed knowledge of hand hygiene before and after the program. The program was aimed at improving the level of understanding and attitudes of students regarding hand hygiene. RESULTS: Of 208 samples obtained, the most frequent agents before and after the educational program were Staphylococcus epidermidis (39% versus 23%) and Staphylococcus aureus (21% versus 15%). The average number of colonies was 236 and 183 respectively (p = 0.35). CONCLUSION: The educational program managed to improve the level of understanding about hand hygiene; however, it was not enough to reduce bacterial colonization, so other behaviors such as direct supervision should be considered.

Humans , Male , Female , Adolescent , Students , Bacterial Infections/prevention & control , Hand Disinfection/standards , Health Knowledge, Attitudes, Practice , Bacteria/isolation & purification , Surveys and Questionnaires , Hand/microbiology
J. appl. oral sci ; 28: e20190266, 2020. graf
Article in English | LILACS, BBO | ID: biblio-1056586


Abstract Objective: The microbial composition of pericoronitis (Pc) is still controversial; it is not yet clear if the microbial profile of these lesions is similar to the profile observed in periodontitis (Pd). Therefore, the aim of the present study was to describe the microbial profile of Pc lesions and compare it directly with that of subjects with Pd. Methodology: Subjects with Pc and Pd were selected, and subgingival biofilm samples were collected from (i) third molars with symptomatic Pc (Pc-T), (ii) contralateral third molars without Pc (Pc-C) and (iii) teeth with a probing depth >3 mm from subjects with Pd. Counts and proportions of 40 bacterial species were evaluated using a checkerboard DNA-DNA hybridization technique. Results: Twenty-six patients with Pc and 18 with Pd were included in the study. In general, higher levels of microorganisms were observed in Pd. Only Actinomyces oris and Eubacterium nodatum were present in higher mean counts in the Pc-T group in comparison with the Pc-C and Pd-C groups (p<0.05). The microbiota associated with Pc-T was similar to that found in Pc-C. Sites with Pc lesions had lower proportions of red complex in comparison with the Pd sites. Conclusion: The microbiota of Pc is very diverse, but these lesions harbour lower levels of periodontal pathogens than Pd.

Humans , Male , Female , Adult , Middle Aged , Aged , Pericoronitis/microbiology , Periodontitis/microbiology , Bacteria/isolation & purification , Reference Values , Activation Analysis , DNA Probes , Cross-Sectional Studies , Biofilms , Bacterial Load , Gingiva/microbiology
J. appl. oral sci ; 28: e20190100, 2020. tab, graf
Article in English | LILACS, BBO | ID: biblio-1056594


Abstract Objective: This clinical study sought to evaluate the effectiveness of passive ultrasonic activation (PUA) in eliminating microorganisms in primary endodontic infection (PEI) after instrumentation of root canals using microbiological culture and checkerboard DNA-DNA hybridization. Methodology: Twenty root canals with PEI and apical periodontitis were selected. The root canals were instrumented and then randomly divided into 2 groups, according to the irrigation method: PUA and conventional needle irrigation (CNI). Microbiological samples were collected before instrumentation (S1), after instrumentation (S2) and after irrigation with 17% EDTA (S3). The samples were subjected to anaerobic culture technique and checkerboard DNA-DNA hybridization analysis. Results: A statistically significant difference was found between CNI (23.56%) and PUA (98.37%) regarding the median percentage values for culturable bacteria reduction (p<0.05). In the initial samples, the most frequently detected species was S. constellatus (50%), and after root canal treatment was E. faecalis (50%). Conclusion: Both treatments significantly decreased the number of bacterial species compared with the initial sample. However, no statistical difference in the total microbial load between PUA and CNI groups was detected. The number of cultivable anaerobic bacteria reduced significantly using PUA, and the bacterial composition and number of bacterial species after using either CNI or PUA was similar.

Humans , Male , Female , Adolescent , Adult , Middle Aged , Periapical Periodontitis/therapy , Root Canal Therapy/instrumentation , Ultrasonic Therapy/instrumentation , Dental Pulp Cavity/microbiology , Root Canal Irrigants/therapeutic use , Root Canal Therapy/methods , Sodium Hypochlorite/therapeutic use , Bacteria/isolation & purification , Ultrasonic Therapy/methods , Colony Count, Microbial , DNA Probes , Linear Models , Analysis of Variance , Treatment Outcome , Cone-Beam Computed Tomography , Bacterial Load , Therapeutic Irrigation/instrumentation , Therapeutic Irrigation/methods
Rev. Assoc. Med. Bras. (1992) ; 65(12): 1502-1507, Dec. 2019. tab, graf
Article in English | LILACS | ID: biblio-1057085


SUMMARY INTRODUCTION Despite the benefits, tracheostomized children are susceptible to respiratory infections, since the tube is located in a strategic region where there is colonization by several bacteria and biofilm formation. Biofilm is formed when the bacteria adhere strongly to the surfaces of the tubes, providing protection against various types of aggression, such as antibiotic treatment. OBJECTIVE To carry out a literature review of the last ten years on tracheostomized pediatric patients, in order to characterize the bacteria isolated in children's tracheal secretions, and verify which ones are the most frequent. METHODS Two authors searched the Lilacs, SciELO, Medline Plus, and PubMed databases. The MeSH terms used were: 'tracheostomy' and 'tracheotomy' associated with 'infections', 'children', 'child', and 'bacterial' as qualifiers. RESULTS Of the 512 studies on the subject, 19 were selected for review. The total number of children evaluated in the studies was 4,472, with a mean age of 7.5 years. As for the bacteria found in the secretions of tracheostomized children, 12 species of bacteria were more frequent, P. aeruginosa was the predominant bacterium, followed by S. aureus (63.1%), Klebsiella pneumoniae (57.8%), Streptococcus pneumoniae (47.3%), and Stenotrophomonas maltophilia (47.3%). CONCLUSION One of the main complications treated in tracheostomized patients were infections, since the respiratory system is colonized by several bacteria that can cause serious infections, which are associated with the formation of biofilms. The predominant bacterium in most of the studies was P. aeruginosa, and the second species commonly reported was S. aureus.

RESUMO INTRODUÇÃO Apesar dos benefícios, crianças traqueostomizadas estão suscetíveis a adquirir infecções respiratórias, pois o tubo se encontra em uma região estratégica, na qual existe colonização de diversas bactérias e formação de biofilme. O biofilme é formado quando as bactérias aderem fortemente às superfícies dos tubos, conferindo proteção contra diversos tipos de agressões, como o tratamento por antibióticos. OBJETIVO Realizar uma revisão de literatura dos últimos dez anos sobre pacientes pediátricos traqueostomizados, no intuito de caracterizar as bactérias isoladas em secreções traqueais de crianças, verificando-se quais são as mais frequentes. MÉTODOS Dois autores pesquisaram nas bases de dados do Lilacs, SciELO, Medline Plus e PubMed. Termos MeSH utilizados: tracheostomy e tracheotomy usados associados a infections, children, chlid e bacterial como qualificadores. RESULTADOS Dos 512 estudos relacionados ao tema, 19 foram selecionados para a revisão. O total de crianças avaliadas nos estudos foi de 4.472, com idade média de 7,5 anos. Quanto às bactérias encontradas nas secreções de crianças traqueostomizadas, 12 espécies de bactérias foram mais frequentes; P. aeruginosa foi a bactéria predominante, seguida de S. aureus (63,1%), Klebsiella pneumoniae (57,8%), Streptococcus pneumoniae (47,3%) e Stenotrophomonas maltophilia (47,3%). CONCLUSÃO Umas das principais complicações abordadas em pacientes traqueostomizados foram as infecções, já que o sistema respiratório é colonizado por diversas bactérias, que podem causar infecções graves, sendo estas associadas à formação de biofilmes. A bactéria predominante na maioria dos estudos foi a P. aeruginosa, e a segunda espécie comumente relatada foi a S. aureus.

Humans , Male , Female , Child , Trachea/microbiology , Tracheostomy/methods , Respiratory Tract Infections/microbiology , Bacteria/isolation & purification
Braz. j. infect. dis ; 23(6): 468-470, Nov.-Dec. 2019. tab
Article in English | LILACS | ID: biblio-1089315


ABSTRACT The precise diagnosis of bacterial meningitis is essential. Cytological and biochemical examination of cerebrospinal fluid (CSF) are not specific. Conventional methods for bacterial meningitis lack sensitivity or take too long for a final result. Therefore, other methods for rapid and accurate diagnosis of central nervous system infections are required. FilmArray meningitis/encephalitis (ME) panel is a PCR multiplex for simultaneous and rapid identification of 14 pathogens, including 6 bacteria, 7 viruses, and Cryptococcus. We evaluated 436 CSF samples submitted to FilmArray ME Panel. Among them, 25 cases were positive for bacteria, being Streptococcus pneumonia the most frequent (48 %). Among positive cases for bacteria, 60 % were positive only with FilmArray. All the bacterial meningitis cases in which the only positive test was FilmArray had CSF findings suggestive of bacterial meningitis, including neutrophilic pleocytosis, increased CSF protein and lactate, and decreased CSF glucose. These findings suggest that FilmArray may increase the diagnostic sensitivity for bacterial meningitis.

Humans , Cerebrospinal Fluid/microbiology , Cerebrospinal Fluid/virology , Meningitis, Bacterial/diagnosis , Multiplex Polymerase Chain Reaction/methods , Bacteria/isolation & purification , Viruses/isolation & purification , Microbial Sensitivity Tests/methods , Sensitivity and Specificity , Meningitis, Bacterial/cerebrospinal fluid
Braz. j. biol ; 79(4): 555-565, Nov. 2019. tab
Article in English | LILACS | ID: biblio-1001469


Abstract Different methodologies have been developed throughout the years to identify environmental microorganisms to improve bioremediation techniques, determine susceptibility profiles of bacteria in contaminated environments, and reduce the impact of microorganisms in ecosystems. Two methods of bacterial biochemical identification are compared and the susceptibility profile of bacteria, isolated from residential and industrial wastewater, is determined. Twenty-four bacteria were retrieved from the bacteria bank of the Environmental Microbiology Laboratory at the Institute of Biology (IB) of the Universidade Federal de Pelotas, Pelotas, Brazil. Bacteria were identified by conventional biochemical tests and by the VITEK ®2 automated system. Further, the susceptibility profile to antibiotics was also determined by the automated system. Six species of bacteria (Raoutella planticola, K. pneumoniae ssp. pneumoniae , Serratia marcescens, Raoutella sp., E. cloacae and Klebsiella oxytoca) were identified by conventional biochemical tests, while three species of bacteria (K. pneumoniae ssp. pneumoniae, S. marcescens and K. oxytoca ) were identified by VITEK®2 automated system. VITEK ®2 indicated agreement in 19 (79.17%) isolates and difference in five (20.83%) isolates when compared to results from conventional biochemical tests. Further, antibiotic susceptibility profile results showed that all isolates (100%) were resistant to at least one out of the 18 antibiotics tested by VITEK®2. Thus, no multi-resistant bacteria that may be used in effluent treatment systems or in bioremediation processes have been reported. Results indicate VITEK ® 2 automated system as a potential methodology in the determination of susceptibility profile and identification of environmental bacteria.

Resumo Diferentes metodologias foram desenvolvidas ao longo dos anos para identificar microrganismos ambientais para melhorar as técnicas de biorremediação, determinar perfis de suscetibilidade de bactérias em ambientes contaminados e reduzir o impacto de microrganismos nos ecossistemas. Dois métodos de identificação bioquímica bacteriana são comparados e o perfil de susceptibilidade de bactérias, isoladas de efluentes residenciais e industriais, é determinado. Vinte e quatro bactérias foram coletadas do banco de bactérias do Laboratório de Microbiologia Ambiental do Instituto de Biologia (IB) da Universidade Federal de Pelotas, Pelotas, Brasil. As bactérias foram identificadas por testes bioquímicos convencionais e pelo sistema automatizado VITEK®2. Além disso, o perfil de suscetibilidade aos antibióticos também foi determinado pelo sistema automatizado. Seis espécies de bactérias (Raoutella planticola , K. pneumoniae ssp. pneumoniae, Serratia marcescens, Raoutella sp., E. cloacae e Klebsiella oxytoca) foram identificadas por testes bioquímicos convencionais, enquanto três espécies de bactérias (K. pneumoniae ssp. pneumoniae, S. marcescens e K. oxytoca) foram identificados pelo sistema automatizado VITEK®2. VITEK®2 indicou concordância em 19 (79,17%) isolados e diferença em cinco (20,83%) isolados quando comparados aos resultados de testes bioquímicos convencionais. Além disso, os resultados do perfil de suscetibilidade aos antibióticos mostraram que todos os isolados (100%) foram resistentes a pelo menos um dos 18 antibióticos testados pelo VITEK®2. Assim, não foram relatadas bactérias multirresistentes que possam ser usadas em sistemas de tratamento de efluentes ou em processos de biorremediação. Os resultados indicam que o sistema automatizado VITEK ® 2 é uma metodologia potencial na determinação do perfil de suscetibilidade e identificação de bactérias ambientais.

Bacteria/isolation & purification , Bacteria/drug effects , Bacteriological Techniques/methods , Drug Resistance, Bacterial , Brazil , Bacteriological Techniques/instrumentation , Anti-Bacterial Agents/pharmacology
Electron. j. biotechnol ; 41: 72-80, sept. 2019. ilus, tab, graf
Article in English | LILACS | ID: biblio-1087172


Background: Microbial community analysis of electronic waste (e-waste)-polluted environments is of interest to understand the effect of toxic e-waste pollutants on the soil microbial community and to evaluate novel microorganisms resisting the toxic environment. The present study aims to investigate the bacterial community structure in soils contaminated with e-waste from various sites of Loni and Mandoli (National Capital Region (NCR), India) where e-waste dumping and recycling activities are being carried out for many years. Results: Interferences to soil metagenomic DNA extraction and PCR amplification were observed because of the presence of inhibiting components derived from circuit boards. Whole-metagenome sequencing on the Illumina MiSeq platform showed that the most abundant phyla were Proteobacteria and Firmicutes. Deltaproteobacteria and Betaproteobacteria were the most common classes under Proteobacteria. Denaturing gradient gel electrophoresis (DGGE) analysis of the bacterial 16S rRNA gene showed that e-waste contamination altered the soil bacterial composition and diversity. There was a decrease in the number of predominant bacterial groups like Proteobacteria and Firmicutes but emergence of Actinobacteria in the contaminated soil samples. Conclusions: This is the first report describing the bacterial community structure of composite soil samples of ewaste-contaminated sites of Loni and Mandoli, Delhi NCR, India. The findings indicate that novel bacteria with potential bioremediating properties may be present in the e-waste-contaminated sites and hence need to be evaluated further.

Soil Microbiology , Bacteria/isolation & purification , Bacteria/genetics , Electronic Waste/analysis , Soil Pollutants , Polymerase Chain Reaction , Metals, Heavy , Proteobacteria/isolation & purification , Metagenomics , Denaturing Gradient Gel Electrophoresis , Microbiota , Firmicutes/isolation & purification , India
Electron. j. biotechnol ; 39: 52-60, may. 2019. ilus, tab, graf
Article in English | LILACS | ID: biblio-1052027


BACKGROUND: Biologically active peptides produced from fish wastes are gaining attention because their health benefits. Proteases produced by halophilic microorganisms are considered as a source of active enzymes in high salt systems like fish residues. Hence, the aim of this study was the bioprospection of halophilic microorganisms for the production of proteases to prove their application for peptide production. RESULTS: Halophilic microorganisms were isolated from saline soils of Mexico and Bolivia. An enzymatic screening was carried out for the detection of lipases, esterases, pHB depolymerases, chitinases, and proteases. Most of the strains were able to produce lipases, esterases, and proteases, and larger hydrolysis halos were detected for protease activity. Halobacillus andaensis was selected to be studied for proteolytic activity production; the microorganism was able to grow on gelatin, yeast extract, skim milk, casein, peptone, fish muscle (Cyprinus carpio), and soy flour as protein sources, and among these sources, fish muscle protein was the best inducer of proteolytic activity, achieving a protease production of 571 U/mL. The extracellular protease was active at 50°C, pH 8, and 1.4 M NaCl and was inhibited by phenylmethylsulfonyl fluoride. The proteolytic activity of H. andaensis was used to hydrolyze fish muscle protein for peptide production. The peptides obtained showed a MW of 5.3 kDa and a radical scavenging ability of 10 to 30% on 2,2-diphenyl-1-picrylhydrazyl and 2,2-azinobis(3-ethylbenzothiazoline-6-sulfonic acid) and a ferric reducing ability of plasma. Conclusion: The use of noncommercial extracellular protease produced by H. andaensis for biologically active peptide production using fish muscle as the protein source presents a great opportunity for high-value peptide production.

Peptide Hydrolases/metabolism , Peptides/metabolism , Fish Proteins/metabolism , Halobacillus/enzymology , Soil , Bacteria/isolation & purification , Bolivia , Esterases , Salinity , Hydrolysis , Lipase , Mexico , Muscle Proteins , Antioxidants
Braz. j. biol ; 79(2): 191-200, Apr.-June 2019. tab, graf
Article in English | LILACS | ID: biblio-989448


Abstract The hygienic and sanitary control in Food and Nutrition Units (FNU) is considered a standard procedure to produce adequate meals and reduce the risk of foodborne diseases and hospital infections. This study aimed to evaluate the isolation and identification of bacteria from equipment and food contact surfaces in a hospital FNU as well as to evaluate the sanitary condition. Likewise, it was analyzed the adhesion of the microorganisms on polyethylene cutting boards. The presence of aerobic mesophilic microorganisms, yeasts, molds, coagulase-positive staphylococci, coliform and fecal coliform, and Escherichia coli were analyzed on eating tables, countertop surfaces and cutting boards used for meat or vegetable handling, and equipment such as microwaves and refrigerators. The molecular identification it was done by 16S rRNA gene sequencing. The adhesion of the microorganisms (biofilm formation) on meat and vegetable cutting boards was also evaluated by scanning electron microscopy. The results showed high numbers of all microorganisms, except for E. coli , which was not observed in the samples. The molecular analysis identified species of the Enterobacteriaceae family and species of the Pseudomonadaceae family. Scanning electron microscopy analyses revealed bacterial adhesion on the cutting board surfaces. The results obtained in this study indicated that the hygienic conditions of surfaces like plastic cutting boards and equipment in this hospital FNU were inadequate. The achievement and application of standard operating procedures could positively help in the standardization of sanitary control, reducing the microbial contamination and providing a safe food to hospitalized patients.

Resumo O controle higiênico e sanitário nas Unidades de Alimentação e Nutrição (UAN) é considerado um procedimento padrão para produzir refeições adequadas e reduzir o risco de doenças transmitidas pelos alimentos e infecções hospitalares. Este estudo teve como objetivo isolar e identificar bactérias de equipamentos e superfícies de contato com alimentos em uma UAN hospitalar, bem como avaliar a condição sanitária. Do mesmo modo, analisou-se a adesão dos micro-organismos em tábuas de corte de polietileno. A presença de micro-organismos aeróbios mesófilos, leveduras, fungos, Sthapylococcus coagulase-positivos, coliformes, coliformes fecais e Escherichia coli foi analisadas na superfície de mesas do refeitório, superfícies de bancada e tábuas de corte usadas para manuseio de carne ou vegetais e, em equipamentos como micro-ondas e refrigeradores. A identificação molecular foi feita pelo sequenciamento do gene 16S rRNA. A adesão dos micro-organismos (formação de biofilmes) em tábuas de corte de carne e de vegetais também foi avaliada por microscopia eletrônica de varredura. Os resultados mostraram elevada contagem para todos os micro-organismos analisados, exceto para E. coli, a qual não foi observada nas amostras. A análise molecular identificou espécies da família Enterobacteriaceae e Pseudomonadaceae. A análise de microscopia eletrônica de varredura revelaram adesão bacteriana nas superfícies das placsa de corte. Os resultados obtidos neste estudo indicaram que as condições higiênicas das superfícies e de equipamentos nesta UAN hospitalar estavam inadequadas. A aplicação de procedimentos operacionais padrão poderia auxiliar positivamente na padronização do controle higiênico-sanitário, reduzindo a contaminação microbiana e fornecendo um alimento seguro para pacientes hospitalizados.

Humans , Environmental Microbiology , Molecular Typing , Food Microbiology , Food Service, Hospital/trends , Bacteria/isolation & purification , Bacteria/classification , Bacteria/genetics , Biofilms , Fungi/isolation & purification , Fungi/classification , Fungi/genetics
Rev. argent. microbiol ; 51(1): 39-46, mar. 2019. ilus
Article in English | LILACS | ID: biblio-1003279


Tributyltin (TBT) is recognized as a major environmental problem at a global scale. Haloalkaliphilic tributyltin (TBT)-degrading bacteria may be a key factor in the remediation of TBT polluted sites. In this work, three haloalkaliphilic bacteria strains were isolated from a TBT-contaminated site in the Mediterranean Sea. After analysis of the 16S rRNA gene sequences the isolates were identified as Sphingobium sp. HS1, Stenotrophomonas chelatiphaga HS2 and Rhizobium borbori HS5. The optimal growth conditions for biodegradation of TBT by the three strains were pH 9 and 7% (w/v) salt concentration. S. chelatiphaga HS2 was the most effective TBT degrader and has the ability to transform most TBT into dibutyltin and monobutyltin (DBT and MBT). A gene was amplified from strain HS2 and identified as TBTB-permease-like, that encodes an ArsB-permease. A reverse transcription polymerase chain reaction analysis in the HS2 strain confirmed that the TBTB-permease-like gene contributes to TBT resistance. The three novel haloalkaliphilic TBT degraders have never been reported previously.

Se considera a la tributiltina (TBT) como un problema medioambiental serio a escala global. Las bacterias haloalcalifílicas degradadoras de TBT pueden constituir un factor clave para remediar áreas contaminadas con dicho xenobiótico. En este estudio se aislaron 3 cepas de bacterias haloalcalifílicas procedentes de un sitio contaminado con TBT en el mar Mediterráneo. Tras analizar las secuencias del gen de 16S del ARNr, se identificaron los aislados como Sphingo-bium sp. HS1, Stenotrophomonas chelatiphaga HS2 y Rhizobium borbori HS5. Las condiciones de crecimiento óptimas para la biodegradación de TBT por parte de las 3 cepas fueron pH 9 y 7% (p/v) de concentración de sal. S. chelatiphaga HS2 fue el degradador de TBT más efectivo, con capacidad de transformar la mayor parte de ese compuesto en dibutiltina y monobutiltina (DBT y MBT). Se amplificó un gen de la cepa HS2, que fue identificado como tipo TBTB-permeasa, que codifica para una ArsB permeasa. Un análisis de la cepa HS2 por reacción en cadena de la polimerasa con transcriptasa inversa (RT PCR) confirmó que el gen TBTB-permeasa contribuye a la resistencia al TBT. Estos 3 nuevos degradadores haloalcalifílicos de TBT no habían sido reportados previamente.

Bacteria/isolation & purification , Environmental Restoration and Remediation/methods , Biodegradation, Environmental , Mediterranean Sea/epidemiology , Polymerase Chain Reaction/methods , Reverse Transcription/genetics , Environmental Restoration and Remediation/analysis
J. appl. oral sci ; 27: e20180635, 2019. tab, graf
Article in English | LILACS | ID: biblio-1012524


Abstract Acetaldehyde, associated with consumption of alcoholic beverages, is known to be a carcinogen and to be related to the tongue dorsum. Objective The aim of this study was to investigate the relationship between acetaldehyde concentration in mouth air and bacterial characteristics on the tongue dorsum. Methodology Thirty-nine healthy volunteers participated in the study. Acetaldehyde concentrations in mouth air were evaluated by a high-sensitivity semiconductor gas sensor. A 16S rRNA gene sequencing technique was used to compare microbiomes between two groups, focusing on the six samples with the highest acetaldehyde concentrations (HG) and the six samples with lowest acetaldehyde concentrations (LG). Results Acetaldehyde concentration increased in correlation with the increase in bacterial count (p=0.048). The number of species observed in the oral microbiome of the HG was higher than that in the oral microbiome of the LG (p=0.011). The relative abundances of Gemella sanguinis, Veillonella parvula and Neisseria flavescens in the oral microbiome of the HG were higher than those in the oral microbiome of the LG (p<0.05). Conclusion Acetaldehyde concentration in mouth air was associated with bacterial count, diversity of microbiome, and relative abundance of G. sanguinis, V. parvula, and N. flavescens.

Humans , Male , Female , Adult , Young Adult , Tongue/microbiology , Microbiota , Acetaldehyde/analysis , Mouth/surgery , Reference Values , Bacteria/isolation & purification , Bacteria/genetics , Tongue/metabolism , Candida/isolation & purification , Alcohol Drinking/metabolism , RNA, Ribosomal, 16S/analysis , RNA, Ribosomal, 16S/metabolism , Smoking/metabolism , Cross-Sectional Studies , Surveys and Questionnaires , Statistics, Nonparametric , Bacterial Load , Japan , Acetaldehyde/metabolism , Mouth/metabolism
Rev. Soc. Bras. Med. Trop ; 52: e20180152, 2019. tab, graf
Article in English | LILACS | ID: biblio-1041546


Abstract INTRODUCTION: Introducing new antibiotics to the clinic is critical. METHODS: We adapted a plate method described by Kawaguchi and coworkers in 20131 for detecting inhibitory airborne microorganisms. RESULTS: We obtained 51 microbial colonies antagonist to Chromobacterium violaceum, purified and retested them, and of these, 39 (76.5%) were confirmed. They comprised 24 bacteria, 13 fungi, and 2 yeasts. Among the fungi, eight (61.5%) produced active extracts. Among the bacterial, yeast, and fungal strains, 17 (44.7%) and 12 (31.6%) were active against Candida albicans and Candida parapsilosis, respectively. CONCLUSIONS: The proposed screening method is a rapid strategy for discovering potential antibiotic producers.

Bacteria/isolation & purification , Candida/drug effects , Chromobacterium/drug effects , Air Microbiology , Quorum Sensing , Fungi/isolation & purification , Anti-Bacterial Agents/isolation & purification , Bacteria/metabolism , Colony Count, Microbial , Fungi/metabolism , Anti-Bacterial Agents/metabolism , Anti-Bacterial Agents/pharmacology
Article in Spanish | LILACS | ID: biblio-1150791


El género Klebsiella tiene importancia en hospitales y sanatorios por su tendencia a causar brotes. Una característica sobresaliente es la resistencia natural y/o adquirida a antimicrobianos. Según la red WHONET - Argentina, existe circulación de Klebsiella en nosocomios, particularmente en salas de terapia intensiva. En este trabajo se evaluó la presencia de Klebsiella spp. en 1233 pacientes de un sanatorio de la ciudad de Resistencia (Chaco), durante el período 2015 ­ 2017. La detección de la bacteria se realizó por cultivo y la sensibilidad se determinó por difusión en agar. Se detectó Klebsiella en 5.6% (69) de las muestras y multirresistencia en 84% de los aislamientos. Se concluye que existe circulación de Klebsiella en la institución, debe ser correctamente identificada y establecido su nivel de resistencia. Esto es fundamental para disminuir los fracasos terapéuticos

The Klebsiella genus is important in hospitals and sanatoriums because of its tendency to cause outbreaks. An outstanding characteristic is the natural and / or acquired resistance to antimicrobials. According to the WHONET-Argentina network, there is Klebsiella circulation in hospitals, particularly in intensive care rooms. In this work, we searched Klebsiella spp. in 1233 patients from a sanatorium in the city of Resistencia (Chaco), during the period 2015 - 2017. The detection of the bacteria was carried out by culture and the sensitivity was determined by agar diffusion. Klebsiella was detected in 5.6% (69) of the samples and multiresistance in 84% of the isolates. It is concluded that there is Klebsiella circulation in the institution, it must be correctly identified and its level of resistance established. This is essential to reduce therapeutic failures

Humans , Bacteria/isolation & purification , Bacterial Infections/diagnosis , Disease Outbreaks , Hospitals , Klebsiella , Nursing Homes , Patients
Braz. oral res. (Online) ; 33: e039, 2019. tab, graf
Article in English | LILACS | ID: biblio-1001610


Abstract: This clinical study compared the effectiveness of two rotary systems: HyFlex CM (Coltene-Whaledent, Altstetten, Switzerland) and ProTaper Next (Dentsply Sirona, Ballaigues, Switzerland) on the removal of cultivable bacteria and endotoxins from primarily infected root canals. This study was designed as a randomized single-blinded, 2-arm, clinical trial. Twenty-four primarily infected root canals were selected and randomly divided into 2 groups: HyFlex CM (n = 12); and ProTaper Next (n = 12). Samples were collected before and after the biomechanical preparation and inoculated in specific flasks. Irrigation was performed using 2.5% sodium hypochlorite. A kinetic turbidimetric lysate assay of limulus amoebocytes was used to quantify endotoxins. Microbiological culture technique was used to determine the count of bacterial colony forming units (CFU/mL). Data collected were statistically analyzed using SigmaPlot 12.0 for Windows. The Two-Way ANOVA statistical test was performed and the level of significance was 5%. In the samples before the biomechanical preparation, cultivable bacteria and endotoxins were evidenced in 100% of the cases. The culture analysis revealed that there was no statistically significant difference in the bacterial reduction between the two instrumentation systems. Endotoxins were present in 100% of the canals after instrumentation and there was no statistical difference between the two systems in endotoxin reduction. Thus, it was concluded that both instrumentation systems were effective in reducing root canal bacteria and endotoxins with primary endodontic infection and that there was no statistical difference between them. However, no system was able to eliminate 100% of the bacteria and their by-products.

Humans , Male , Female , Adult , Bacteria/isolation & purification , Lipopolysaccharides/analysis , Dental Instruments , Dental Pulp Cavity/microbiology , Materials Testing , Bacteriological Techniques , Treatment Outcome , Root Canal Preparation/instrumentation , Endotoxins/analysis , Bacterial Load , Middle Aged
Braz. oral res. (Online) ; 33(supl.1): e064, 2019. tab, graf
Article in English | LILACS | ID: biblio-1039323


Abstract The aim was of this study was to determine the current weight of evidence for the existence of specific differences between the microbiota of healthy teeth and healthy implants, or of teeth with periodontitis and implants with peri-implantitis. A systematic review was conducted according to the PRISMA statement. The MEDLINE, EMBASE and Cochrane databases were searched up to February 2018 for studies comparing microbiological data of biofilm samples collected from healthy teeth and implants or from teeth with periodontitis and implants with peri-implantitis. The weight of evidence was defined in three categories (strong, moderate and mild/some), according to the difference in number of studies showing statistically significantly higher counts and/or proportions and/or abundance and/or prevalence of microorganisms in health or in disease. Of the 132 articles identified, 8 were included. A wide range of microorganisms were present in different conditions but no microorganisms showed strong, moderate or mild/some evidence for a specific association with either teeth or implants. The results of this systematic review indicated that there is insufficient evidence in the literature to support specific differences between microorganisms colonizing teeth and implants, either in health or in disease.

Humans , Periodontitis/microbiology , Dental Implants/microbiology , Peri-Implantitis/microbiology , Gingiva/microbiology , Bacteria/isolation & purification , Case-Control Studies , Biofilms/growth & development , Dental Plaque/microbiology , Microbiota