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1.
Lett Appl Microbiol ; 75(4): 924-932, 2022 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-35707938

RESUMO

The objectives were to study the diversity of Enterococcus spp. isolated from mastitis cases, milking equipment and the environment of dairy cows; and to determine in vitro resistance of isolates to antimicrobials that are relevant to human and animal health. Ten dairy farms were visited to collect samples from mastitis cases, faeces, bedding, aisles, water and milking equipment. Identification of Enterococcus at the species level and antimicrobial resistance testing was performed by MALDI-TOF and the disk-diffusion method, respectively. Of 365 isolates, Enterococcus hirae was the most prevalent, being more likely to be isolated from faeces than from milk (odds ratio (OR) = 39·2), liners (OR = 5·4) or bedding (OR = 2·2). Enterococcus saccharolyticus was the most prevalent in milk samples. The chances of isolating Enterococcus faecalis from milk were higher than from aisles (OR = 12·5), faeces (OR = 5·3), bedding (OR = 3·6) or liners (OR = 3·0). The odds of isolating Enterococcus faecium from faeces were higher than from liners (OR = 7·3), bedding (OR = 2·5) or aisles (OR = 2·4). Of 360 tested isolates, 1·9, 0·3 and 0·6% were resistant to penicillin, vancomycin and teicoplanin, respectively. Our results suggest that Enterococcus species can occupy specific ecological niches on dairy farms and pose a risk to public and animal health.


Assuntos
Mastite Bovina , Leite , Animais , Antibacterianos/farmacologia , Bovinos , Farmacorresistência Bacteriana , Enterococcus , Feminino , Humanos , Mastite Bovina/epidemiologia , Testes de Sensibilidade Microbiana , Penicilinas , Teicoplanina , Vancomicina , Água
2.
Arq. bras. med. vet. zootec. (Online) ; 72(3): 1034-1038, May-June, 2020.
Artigo em Inglês | LILACS, VETINDEX | ID: biblio-1129736

RESUMO

Algumas espécies de Staphylococcus causam infecções crônicas intramamárias e podem levar à formação de biofilme. No presente estudo, levantou-se a hipótese de que as espécies de Staphylococcus isolados da mastite bovina são capazes de formar biofilme in vitro associado à presença dos genes icaA, icaD ou bap. Um total de 200 isolados de Staphylococcus, sendo 100 Staphylococcus aureus de casos de mastite subclínica e 100 estafilococos não aureus (ENA) de casos de mastite subclínica e clínica, obtidos em duas fazendas leiteiras, no estado de São Paulo, foram avaliados quanto à capacidade de produzir biofilmes in vitro. A presença de icaA, icaD e bap foi confirmada por PCR, e a produção de biofilme em ágar vermelho congo (Congo Red Agar - CRA) e em teste de microplaca (Microtiter Plate - MtP) foi avaliada nos isolados de S. aureus e ENA. Os resultados mostraram a presença dos genes icaA, icaD e bap em S. aureus, mas não em ENA. A produção de biofilme pode estar associada à presença de outros fatores ou genes que estimulam a produção de biofilme in vitro. O ensaio de MtP serve como um modelo quantitativo para o estudo da aderência de espécies de estafilococos associados à mastite bovina.(AU)


Assuntos
Animais , Feminino , Bovinos , Staphylococcus/isolamento & purificação , Staphylococcus aureus/isolamento & purificação , Biofilmes , Mastite Bovina/diagnóstico , Reação em Cadeia da Polimerase/veterinária , Ágar
3.
Microb Pathog ; 132: 45-50, 2019 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-31015015

RESUMO

Bovine mastitis affects dairy cattle worldwide and Staphylococcus aureus is one of the most common microorganisms involved in subclinical and chronic disease. Superantigens, such as enterotoxins contribute to S. aureus persistence and pathogenicity in this disease. Subclinical and chronic mastitis cases were diagnosed and S. aureus isolates from sub-clinical cases were investigated for carriage of virulence and antibiotic resistance genes that may contribute to long-term carriage and infection. Over a 12-month period, 116 S. aureus strains were recovered from 68 cows with subclinical mastitis. Classical enterotoxin genes (sea-see) were detected in 24.1% of isolates, and pvl and tsst-1 were identified in 3.4% and 46.6% the isolates, respectively. 18.1% that were persistent isolates were identified and characterized by pulsed field gel electrophoresis (PFGE), MLST, spa typing. Four isolates were methicillin-resistant S. aureus (MRSA) and belonged to SCCmec type I. Molecular typing showed that the agrI group was the most frequent, and a rare isolate was positive for both agrI and agrIII groups. Molecular characterization revealed the persistence of the spa type t10856 (ST133, clonal complex CC133, agr I), in a single animal for nine months and the persistence t605 (ST126, CC126) colonizing four animals for four months. These strains have been described recently in other herds in the same region, indicating their transmissibility and clonal expansion. We conclude that animals with subclinical mastitis are an important and somewhat overlooked reservoir for transmission within and between herds, and may carry virulence and antibiotic resistance genes contributing to persistent colonization, hinder the control of mastitis and may cause risks to the public health.


Assuntos
Genótipo , Mastite Bovina/microbiologia , Infecções Estafilocócicas/microbiologia , Infecções Estafilocócicas/veterinária , Staphylococcus aureus/genética , Staphylococcus aureus/patogenicidade , Animais , Antibacterianos/farmacologia , Proteínas de Bactérias/genética , Toxinas Bacterianas/genética , Bovinos , DNA Bacteriano , Eletroforese em Gel de Campo Pulsado , Enterotoxinas/genética , Exotoxinas/genética , Feminino , Leucocidinas/genética , Staphylococcus aureus Resistente à Meticilina/genética , Testes de Sensibilidade Microbiana , Leite/microbiologia , Tipagem Molecular/métodos , Tipagem de Sequências Multilocus , Staphylococcus aureus/isolamento & purificação , Superantígenos/genética , Transativadores/genética , Virulência/genética , Fatores de Virulência/genética
4.
J Appl Microbiol ; 126(2): 516-522, 2019 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-30431699

RESUMO

AIMS: The study was focused on the evaluation of antimicrobial activity in vitro of the essential oil (EO) of leaves from Schinus molle against bacteria and fungi of clinical importance in the search for the discovery of new active compounds. METHODS AND RESULTS: The chemical composition of the S. molle EO was determined by gas chromatography/mass spectrometry and its antimicrobial effect was verified by broth microdilution method. The major compounds found were ß-pinene (25·23%), epi-α-cadinol (21·29%), α-pinene (18·72%), myrcene (11·54%) and sabinene (5·02%). The EO showed significant antifungal activity against Paracoccidioides brasiliensis (39·06 µg ml-1 ), weak action against Cryptococcus neoformans (625 µg ml-1 ) and Trichophyton quinckeanum (625 µg ml-1 ) and was inactive against Candida sp. In the analysis of the antibacterial action, the micro-organisms tested did not show sensitivity. CONCLUSIONS: This study showed a promising result of S. molle volatiles against the fungus P. brasiliensis, which causes paracoccidioidomycosis (PCM), a systemic mycosis of great clinical importance in Latin America. SIGNIFICANCE AND IMPACT OF THE STUDY: The results found here are novel and encourage investigations of the compounds present in this EO, which represents a source of molecules with potential use in the treatment of PCM.


Assuntos
Anacardiaceae/química , Antibacterianos/farmacologia , Antifúngicos/farmacologia , Óleos Voláteis/farmacologia , Óleos de Plantas/farmacologia , Monoterpenos Acíclicos , Alcenos/análise , Antibacterianos/química , Antifúngicos/química , Monoterpenos Bicíclicos , Compostos Bicíclicos com Pontes/análise , Cryptococcus neoformans/efeitos dos fármacos , Monoterpenos/análise , Óleos Voláteis/química , Paracoccidioides/efeitos dos fármacos , Folhas de Planta/química , Óleos de Plantas/química , Terpenos/análise , Trichophyton/efeitos dos fármacos
5.
Microb Pathog ; 124: 130-135, 2018 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-30138758

RESUMO

Bovine mastitis has been a concern for dairy herd for decades. The adaptation capacity of one of the main species responsible for this disease, Staphylococcus aureus (S. aureus), plays a pivotal role in this issue. The aim of this study was to establish a molecular and phenotypic profile of 285 S. aureus strains isolated from milk of subclinical mastitis cows from 18 different farms in São Paulo State using spa typing, multilocus sequence typing (MLST), pulsed field gel electrophoresis (PFGE), agr cluster (I, II, III and IV) typing, PCR for genes including enterotoxins (sea, seb, sec, sed, see, seg, seh, sei), toxic shock syndrome toxin (tsst-1), and Panton-Valentine leucocidin (pvl), as well as in vitro resistance assays for 12 antibiotics. The results showed a wide variety of strains with a high toxigenic potential; concomitantly, sec, seg and seh were prevalent. In addition, we observed a predominance of the spa types t605 (ST 126, CC126) and t127 (ST1, CC1) and the unusual presence of t321 causing bovine mastitis, which has been previously reported only in swine. The most frequent ST were ST126 (70.5%) and ST1 (10.5%). Regarding PFGE, we observed four major groups and six profile patterns. The highest resistance was observed for streptomycin (9.5%), followed by tetracycline (3.5%), clindamycin (9.3%), and erythromycin (2.8%). The tsst-1 gene was detected in 36.8% of isolates and pvl was not observed. One hundred and thirty-six (47.7%) isolates possessed agr type II, followed by types III (20%) and I (8.1%), with type IV not being detected. We observed that the same spa type could result in different PFGE profiles, so the exclusive use of spa type sequences can lead to incorrect interpretations regarding the spread of clones in an epidemiological context.


Assuntos
Infecções Assintomáticas , Mastite Bovina/epidemiologia , Mastite Bovina/microbiologia , Leite/microbiologia , Infecções Estafilocócicas/veterinária , Staphylococcus aureus/classificação , Staphylococcus aureus/genética , Animais , Antibacterianos/farmacologia , Brasil/epidemiologia , Bovinos , Farmacorresistência Bacteriana , Eletroforese em Gel de Campo Pulsado , Técnicas de Genotipagem , Epidemiologia Molecular , Tipagem de Sequências Multilocus , Reação em Cadeia da Polimerase , Infecções Estafilocócicas/epidemiologia , Infecções Estafilocócicas/microbiologia , Staphylococcus aureus/efeitos dos fármacos , Staphylococcus aureus/isolamento & purificação , Fatores de Virulência/genética
6.
J Dairy Sci ; 101(11): 10220-10229, 2018 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-30146291

RESUMO

The objectives of this study were to estimate the accuracy of Somaticell (Idexx Laboratories Inc., Westbrook, ME), California Mastitis Test (CMT), and microbiological examination of composite milk (MEC) to diagnose Streptococcus agalactiae intramammary infections (IMI), and to assess the agreement between Somaticell and CMT to detect these infections. A secondary objective was to estimate quarter- and cow-level prevalence of S. agalactiae IMI in the herds included in the study. Seven farms were included in the study. The CMT was performed and aseptic milk samples were collected from all quarters of all lactating cows. Composite milk samples were produced in the laboratory by mixing milk from all quarters of each sampled cow. The Somaticell test was performed on a subset of S. agalactiae-positive (n = 167) and S. agalactiae-negative (n = 152) quarter milk samples. Microbiological examination of quarter milk samples (MEQ) was considered the reference test for diagnosing S. agalactiae IMI. The accuracy of all tests at various thresholds was estimated using Bayesian latent class models. Apparent prevalence of S. agalactiae IMI was 15.8% (n = 184/1,164) at the quarter level (based on MEQ) and 28.5% (n = 83/291) at the cow level (based on MEC). True prevalence, as determined by Bayesian models, was 13.0% [95% credible interval (CR): 6.4-24.4%] at the quarter level, and 25.6% (95% CR: 15.3-39.5%) at the cow level. At the cow level (n = 285), sensitivity and specificity of MEC were 95.6 and 99.5%, respectively. The accuracy of Somaticell (n = 319 quarters) to identify S. agalactiae-infected quarters was 75.4, 86.4, 88.9, 89.4, and 91.0% at thresholds of 98,000, 147,000, 205,000, 244,000, and 282,000 cells/mL, respectively. The accuracy of CMT was 87.6, 90.7, 90.8, and 87.4% at thresholds of trace, 1, 2, and 3, respectively. The areas under the receiver operating characteristic curve for Somaticell and CMT were 94.5% (95% confidence interval: 91.8-97.2%) and 92.0% (88.6-95.4%), respectively. At the tested thresholds, the sensitivity of Somaticell ranged from 94.9 to 99.5% to detect S. agalactiae IMI, and specificity ranged from 48.1 to 87.1%. The sensitivity of Somaticell at the lowest threshold (69,000 cells/mL; sensitivity = 99.9%; 95% CR: 98.2-100%) was higher than that of CMT at any tested threshold. Results of this study could be used at the farm level to reduce the use of antimicrobials and reach specific goals in S. agalactiae eradication programs.


Assuntos
Mastite Bovina/diagnóstico , Leite/microbiologia , Infecções Estreptocócicas/veterinária , Streptococcus agalactiae/isolamento & purificação , Animais , Teorema de Bayes , California/epidemiologia , Bovinos , Fazendas , Feminino , Lactação , Mastite Bovina/epidemiologia , Mastite Bovina/microbiologia , Leite/normas , Prevalência , Sensibilidade e Especificidade , Infecções Estreptocócicas/diagnóstico , Infecções Estreptocócicas/epidemiologia , Infecções Estreptocócicas/microbiologia
7.
J Dairy Sci ; 98(9): 5899-904, 2015 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-26142866

RESUMO

Bovine mastitis is an inflammation of the mammary glands of cows and causes significant economic losses in dairy cattle. Staphylococcus aureus is one of the microorganisms most commonly isolated. Novel agents are required in agricultural industries to prevent the development of mastitis. The production of biofilm by Staph. aureus facilitates the adhesion of bacteria to solid surfaces and contributes to the transmission and maintenance of these bacteria. The effect of the essential oils of Syzygium aromaticum (clove; EOSA) and Cinnamomum zeylanicum (cinnamon; EOCZ) and their major components, eugenol and cinnamaldehyde, on Staph. aureus biofilm formation on different surfaces was investigated. The results showed a significant inhibition of biofilm production by EOSA on polystyrene and stainless steel surfaces (69.4 and 63.6%, respectively). However, its major component, eugenol, was less effective on polystyrene and stainless steel (52.8 and 19.6%, respectively). Both EOCZ and its major component, cinnamaldehyde, significantly reduced biofilm formation on polystyrene (74.7 and 69.6%, respectively) and on stainless steel surfaces (45.3 and 44.9%, respectively). These findings suggest that EOSA, EOCZ, and cinnamaldehyde may be considered for applications such as sanitization in the food industry.


Assuntos
Cinnamomum zeylanicum/química , DNA Bacteriano/isolamento & purificação , Mastite Bovina/microbiologia , Infecções Estafilocócicas/tratamento farmacológico , Staphylococcus aureus/isolamento & purificação , Syzygium/química , Acroleína/análogos & derivados , Acroleína/farmacologia , Animais , Biofilmes , Bovinos , DNA Bacteriano/genética , Eugenol/farmacologia , Feminino , Contaminação de Alimentos , Microbiologia de Alimentos , Cromatografia Gasosa-Espectrometria de Massas , Testes de Sensibilidade Microbiana , Leite/microbiologia , Óleos Voláteis/farmacologia , Infecções Estafilocócicas/veterinária , Staphylococcus aureus/efeitos dos fármacos , Staphylococcus aureus/crescimento & desenvolvimento
8.
Lett Appl Microbiol ; 59(6): 665-9, 2014 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-25236329

RESUMO

UNLABELLED: The objective of this study was to analyse the prevalence and molecular characteristics of methicillin-resistant Staphylococcus aureus (MRSA) in milk of cows with mastitis. The California mastitis test (CMT) was used to detect the presence of mastitis in all 100 cows of a farm in Brazil. The CMT was positive in milk of 115 mammary quarters from 36 cows (36%). MRSA isolates were recovered from 4 of these 36 cows with mastitis (11%), and they were further characterized (one MRSA/sample). The four MRSA isolates were typed as t011-ST398-agr1-SCCmecV and presented two different pulsed-field-gel-electrophoresis-ApaI patterns. These four MRSA isolates showed resistance to tetracycline, streptomycin and ciprofloxacin, carried the mecA, blaZ, tet(K), and tet(M) resistance genes, and presented the S84L and S80F amino acid substitutions in GyrA and GrlA proteins, respectively. Two ST398 isolates exhibited resistance to gentamicin and tobramycin [with aac(6)-aph(2") and ant(4)-Ia genes] and one isolate resistance to clindamycin [with lnu(B) and lsa(E) genes]; this latter isolate also carried the spectinomycin/streptomycin resistance genes spw and aadE. MRSA of lineage ST398 is worldwide spread, normally multidrug resistant and may be responsible for bovine mastitis. To our knowledge, this is the first detection of MRSA-ST398 in Brazil. SIGNIFICANCE AND IMPACT OF THE STUDY: Few studies on the epidemiology of methicillin-resistant Staphylococcus aureus (MRSA) from bovine isolates have been performed in Brazil. MRSA of lineage ST398 is worldwide spread and associated with farm animals. Multidrug-resistant MRSA-ST398 isolates were recovered in 11% of mastitic cows from a single farm, with one isolate carrying the unusual lsa(E), spw and aadE genes. To our knowledge, this is the first detection of MRSA-ST398 isolates in milk samples of cows with mastitis in Brazil.


Assuntos
Antibacterianos/farmacologia , Mastite Bovina/microbiologia , Staphylococcus aureus Resistente à Meticilina/efeitos dos fármacos , Staphylococcus aureus Resistente à Meticilina/isolamento & purificação , Leite/microbiologia , Infecções Estafilocócicas/veterinária , Animais , Brasil , Bovinos , Farmacorresistência Bacteriana Múltipla/genética , Eletroforese em Gel de Campo Pulsado , Feminino , Genes Bacterianos , Staphylococcus aureus Resistente à Meticilina/classificação , Staphylococcus aureus Resistente à Meticilina/genética , Testes de Sensibilidade Microbiana , Tipagem Molecular , Reação em Cadeia da Polimerase/veterinária , Infecções Estafilocócicas/microbiologia
9.
J Dairy Sci ; 97(2): 829-37, 2014 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-24359821

RESUMO

The objectives of this study were to determine the occurrence and diversity of Staphylococcus spp. in milk from healthy cows and cows with subclinical mastitis in Brazil and to examine the profile of enterotoxin genes and some enterotoxins produced by Staphylococcus spp. A total of 280 individual mammary quarter milk samples from 70 healthy cows and 292 samples from 73 cows with subclinical mastitis were collected from 11 farms in the state of São Paulo, Brazil. Staphylococcus spp. were recovered from 63 (22.5%) samples from healthy cows and from 80 samples (27.4%) from cows with mastitis. The presence of Staphylococcus aureus was significantly different between these 2 groups and was more prevalent in the cows with mastitis. The presence of Staphylococcus saprophyticus was also significantly different between these 2 groups, but this organism was more prevalent in healthy cows. No statistically significant differences were observed in the numbers of other staphylococci in milk samples from the 2 groups. The sea gene was the most prevalent enterotoxin gene in both groups. Eight of 15 (53.3%) Staph. aureus carried this gene and all produced the SEA toxin. In the coagulase-negative staphylococci (CNS) group, 61 of 128 (47.5%) had the same gene and just 1 (1.6%) Staphylococcus epidermidis strain produced the enterotoxin in vitro. Because CNS were isolated from both groups of cows and most CNS contained enterotoxin genes but did not produce toxins, the role of CNS in mastitis should be carefully defined.


Assuntos
Doenças dos Bovinos/epidemiologia , Enterotoxinas/genética , Genes Bacterianos , Mastite Bovina/epidemiologia , Staphylococcus/fisiologia , Animais , Infecções Assintomáticas/epidemiologia , Brasil/epidemiologia , Bovinos , Doenças dos Bovinos/microbiologia , Enterotoxinas/metabolismo , Feminino , Testes de Fixação do Látex/veterinária , Mastite Bovina/microbiologia , Microbiota , Leite/microbiologia , Reação em Cadeia da Polimerase/veterinária , Staphylococcus/genética
10.
J Dairy Sci ; 96(11): 6856-6862, 2013.
Artigo em Inglês | MEDLINE | ID: mdl-24054305

RESUMO

Mastitis is an important disease for the dairy industry worldwide, causing economic losses and reducing milk quality and production. Staphylococcus aureus is a worldwide agent of this intramammary infection, which also causes foodborne diseases. The objective of this study was to determine the frequency of methicillin-susceptible Staphylococcus aureus (MSSA) isolates in milk of mastitis cows in Brazil and to analyze the genetic lineages and the content of antimicrobial resistance genes and virulence factors among these isolates. Fifty-six MSSA isolates were recovered from 1,484 milk samples (positive for the California mastitis test) of 518 cows from 11 different farms in Brazil (representing 51% of total Staph. aureus obtained), and they were further characterized. Methicillin-susceptible Staphylococcus aureus were isolated from 3.7% of California mastitis test-positive tested milk samples and from 6.2% of tested mastitic cows. Methicillin-susceptible Staphylococcus aureus isolates were characterized by spa typing, agr typing, and multilocus sequence typing, and resistance and virulence traits were investigated by PCR. Seven spa types were identified among MSSA (% of isolates): t127 (44.6), t605 (37.5), t002, t1784, t2066 (1.8), and 2 new ones: t10856 (10.7) and t10852 (1.8). Five distinct sequence types (ST) were detected (% of isolates): ST1 (46.4), ST126 (37.5), ST133 (10.7), ST5 (3.6), and a novel ST registered as ST2493 (1.8). Resistances were detected for streptomycin, chloramphenicol, and tetracycline. One strain contained the chloramphenicol resistance gene (fexA; included within transposon Tn558) and 3 strains contained the tetracycline resistance gene [tet(K)]. Methicillin-susceptible Staphylococcus aureus strains were susceptible to most of the antibiotics studied and lacked the virulence genes of Panton-Valentine leukocidin (lukF/S-PV), toxic shock syndrome toxin 1 (tst), exfoliative toxin A (eta), and exfoliative toxin B (etb), as well as the genes of the immune evasion cluster. Methicillin-susceptible Staphylococcus aureus isolates were detected in a relatively low proportion of cows with mastitis (6.2%) and recovered isolates presented high diversity of genetic lineages, with CC1 and CC126 the predominant clonal complexes, and CC133 also being detected. Larger epidemiological studies with molecular characterization of isolates are required to deepen the knowledge on the circulating genetic lineages among the cow population with mastitis.


Assuntos
Variação Genética , Mastite Bovina/microbiologia , Leite/microbiologia , Infecções Estafilocócicas/veterinária , Staphylococcus aureus/genética , Animais , Antibacterianos/farmacologia , Técnicas de Tipagem Bacteriana , Brasil , Bovinos , Farmacorresistência Bacteriana/genética , Feminino , Testes de Sensibilidade Microbiana , Tipagem de Sequências Multilocus , Infecções Estafilocócicas/microbiologia , Staphylococcus aureus/classificação , Staphylococcus aureus/efeitos dos fármacos , Staphylococcus aureus/isolamento & purificação , Fatores de Virulência/genética
11.
Nat Prod Res ; 26(18): 1721-3, 2012.
Artigo em Inglês | MEDLINE | ID: mdl-21999302

RESUMO

The use of essential oils (EOs) in functional foods containing probiotic microorganisms must consider the antimicrobial activity of these oils against beneficial bacteria such as Lactobacillus rhamnosus. This study aimed to evaluate the sensitivity of L. rhamnosus cultures treated with cinnamon EO through viable cell counts and visualisation by transmission electron microscopy. Cinnamon EO at a concentration of 0.04% had a bacteriostatic activity after 2 h of incubation. Although slight alterations were detected in the cell structure, this concentration was considered to be bactericidal, since it led to a significant reduction in cell numbers after 24 h. On the other hand, cinnamon EO at a 1.00% concentration decreased cell counts by 3 log units after 2 h incubation and no viable cell count was detected after 24 h. Transmission electron microscopy indicated that cells treated with 1.00% cinnamon EO were severely damaged and presented cell membrane disruption and cytoplasmic leakage.


Assuntos
Cinnamomum zeylanicum/química , Lacticaseibacillus rhamnosus/efeitos dos fármacos , Lacticaseibacillus rhamnosus/ultraestrutura , Óleos Voláteis/química , Óleos Voláteis/farmacologia , Testes de Sensibilidade Microbiana , Microscopia Eletrônica de Transmissão
12.
J. venom. anim. toxins incl. trop. dis ; 17(2): 159-167, 2011. graf, tab
Artigo em Inglês | LILACS | ID: lil-587775

RESUMO

In the present study, Apis mellifera propolis and essential oils (EOs) obtained from aromatic plants were evaluated as alternative antimicrobials. We aimed to establish the antimicrobial activity of ethanolic extracts of propolis (EEP) from Apis mellifera and of EOs from Caryophyllus aromaticus, Zingiber officinale, Cinnamomum zeylanicum and Mentha piperita against 32 Staphylococcus aureus and Escherichia coli strains from human clinical specimens. The antimicrobials were diluted in agar and the minimal inhibitory concentrations (MIC) were found whereas MIC90 percent values were calculated. Time-kill curve assays using mixtures containing one quarter of MIC90 percent for EEP with all EOs as well cinnamon EO were performed. The cinnamon EO was found to be the most efficient, with MIC90 percent values of 1.22 and 0.96 mg x mL-1 respectively against S. aureus and E. coli, whereas MIC90 percent of EEP were 1.86 and 20.12 mg x mL-1 respectively against S. aureus and E. coli. The combinations of EEP with ginger and mint EOs, and cinnamon with ginger and clove EOs, showed synergistic effects. Consequently, further studies are necessary to confirm these activities in vivo and to evaluate the phytochemical characteristics of natural products.


Assuntos
Abelhas , Produtos Biológicos , Escherichia coli , Óleos Voláteis , Própole/antagonistas & inibidores , Staphylococcus aureus , Extratos Aromáticos
13.
Braz. j. microbiol ; 41(1): 59-65, Jan.-Mar. 2010. ilus, tab
Artigo em Inglês | LILACS | ID: lil-531735

RESUMO

Food handlers, an important factor in food quality, may contain bacteria that are able to cause foodborne disease. The present study aimed to research coagulase-negative (CNS) and -positive staphylococci (CPS) in 82 food handlers, analyzing nasal and hand swabs, with identification of 62 CNS (75.6 percent) and 20 CPS strains (24.4 percent). Staphylococcal enterotoxins genes were investigated by PCR. In 20 CPS strains, 19 were positive for one or more genes. The percentage of CNS presenting genes for enterotoxins was high (46.8 percent). Despite of the staphylococcal species, the most common gene was sea (35.4 percent), followed by seh and sej (29.2 percent). The detection of new staphylococcal enterotoxins (SEs) genes showed a higher pathogenic potential in this genus. The presence of these gene points out the importance of CNS not only as contaminant bacteria but also as a pathogen.


Assuntos
Coagulase/análise , Coagulase/isolamento & purificação , Enterotoxinas/genética , Enterotoxinas/isolamento & purificação , Manipulação de Alimentos , Cavidade Nasal , Reação em Cadeia da Polimerase , Amostras de Alimentos , Métodos , Métodos
14.
Braz J Microbiol ; 41(1): 59-65, 2010 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-24031464

RESUMO

Food handlers, an important factor in food quality, may contain bacteria that are able to cause foodborne disease. The present study aimed to research coagulase-negative (CNS) and -positive staphylococci (CPS) in 82 food handlers, analyzing nasal and hand swabs, with identification of 62 CNS (75.6%) and 20 CPS strains (24.4%). Staphylococcal enterotoxins genes were investigated by PCR. In 20 CPS strains, 19 were positive for one or more genes. The percentage of CNS presenting genes for enterotoxins was high (46.8%). Despite of the staphylococcal species, the most common gene was sea (35.4%), followed by seh and sej (29.2%). The detection of new staphylococcal enterotoxins (SEs) genes showed a higher pathogenic potential in this genus. The presence of these gene points out the importance of CNS not only as contaminant bacteria but also as a pathogen.

15.
J Food Prot ; 72(2): 421-4, 2009 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-19350991

RESUMO

The aim of this work was to assess the microbiological quality of spices sold in Botucatu, São Paulo, Brazil. A total of 233 samples were analyzed for mesophilic bacteria, thermotolerant coliforms, Bacillus cereus, Staphylococcus aureus, and Salmonella. Data showed that 21 and 5.6% of these samples were not in agreement with the standards of Brazilian law, due to an excess of coliforms and to the presence of Salmonella, respectively. Black pepper and cumin exhibited the lowest microbiological quality, whereas bay leaf showed the highest quality. It was concluded that the seasonings possessed poor microbiological quality, and new alternatives should be taken in the primary production in order to improve this quality. Irradiation may also be a tool to assure the safety of these products.


Assuntos
Enterobacteriaceae/isolamento & purificação , Contaminação de Alimentos/análise , Manipulação de Alimentos/métodos , Salmonella/isolamento & purificação , Especiarias/microbiologia , Brasil , Qualidade de Produtos para o Consumidor , Enterobacteriaceae/crescimento & desenvolvimento , Irradiação de Alimentos , Microbiologia de Alimentos , Controle de Qualidade , Salmonella/crescimento & desenvolvimento , Especiarias/normas
16.
Vet Microbiol ; 132(3-4): 408-13, 2008 Dec 10.
Artigo em Inglês | MEDLINE | ID: mdl-18572331

RESUMO

Milk is considered a nutritious food because it contains several important nutrients including proteins and vitamins. Conversely, it can be a vehicle for several pathogenic bacteria such as Staphylococcus aureus. This study aimed to analyze the frequency of genes encoding the staphylococcal enterotoxins (SEs) SEA, SEB, SEC, SED, SEE, SEG, SEH, SEI and SEJ in S. aureus strains isolated from raw or pasteurized bovine milk. S. aureus was found in 38 (70.4%) out of 54 raw milk samples at concentrations of up to 8.9 x 10(5) CFU/ml. This microorganism was present in eight samples of pasteurized milk before the expiration date and in 11 samples analyzed on the expiration date. Of the 57 strains studied, 68.4% were positive for one or more genes encoding the enterotoxins, and 12 different genotypes were identified. The gene coding for enterotoxin A, sea, was the most frequent (16 strains, 41%), followed by sec (8 strains, 20.5%), sed (5 strains, 12.8%), seb (3 strains, 7.7%) and see (2 strains, 5.1%). Among the genes encoding the other enterotoxins, seg was the most frequently observed (11 strains, 28.2%), followed by sei (10 strains) and seh and sej (3 strains each). With the recent identification of new SEs, the perceived frequency of enterotoxigenic strains has increased, suggesting that the pathogenic potential of staphylococci may be higher than previously thought; however, further studies are required to assess the expression of these new SEs by S. aureus, and their impact in foodborne disease. The quality of Brazilian milk is still low, and efforts from the government and the entire productive chain are required to attain consumer safety.


Assuntos
Enterotoxinas/genética , Leite/microbiologia , Reação em Cadeia da Polimerase , Staphylococcus aureus/genética , Animais , Bovinos , Microbiologia de Alimentos
17.
Arq. bras. med. vet. zootec ; 60(3): 667-674, jun. 2008. ilus, graf, tab
Artigo em Inglês | LILACS | ID: lil-487913

RESUMO

This study reported the pulmonary, microbiological, and hematological alterations in Crotalus durissus terrificus parasitized by nematodes of the genus Rhabdias. Histological, microbiological, and hematological analysis were performed on parasitized (n=6) and non-parasitized (n=6) snakes. Granulocytic and mononuclear cell infiltrates in the pulmonary parenchyma and epithelium were also observed during the histological analysis of parasitized snakes. Microbiological analysis of parasitized animals revealed the following Gram-negative bacteria: Citrobacter divergens, Burkholderia cepacia, Stenotrophomonas maltophilia, Proteus vulgaris, Enterobacter sakazakii, Enterobacter ammnigenus, Pseudomonas aeruginosa, Pantoea sp. and Providencia rettgeri. In non-parasitized snakes, the following species were identified: B. cepacia, Pseudomonas fluorescens, and Acinetobacter baumanii. Increased levels of plasmatic protein, decreased lymphocyte counts, and normal red blood cell values were observed in parasitized animals.


Este trabalho relata as alterações pulmonares, microbiológicas e hematológicas em Crotalus durissus terrificus parasitadas pelo nematódeo do gênero Rhabdias. As análises histológicas, microbiológicas e hematológicas foram realizadas em serpentes parasitadas (n=6) e não parasitadas (n=6). Foram observados infiltrados de células granulocíticas e mononucleares no parênquima pulmonar durante a análise histopatológica das serpentes parasitadas. A análise microbiológica revelou as seguintes bactérias Gram-negativas; Citrobacter divergens, Burkholderia cepacia, Stenotrophomonas maltophilia, Proteus vulgaris, Enterobacter sakazakii, Enterobacter ammnigenus, Pseudomonas aeruginosa, Pantoea sp. e Providencia rettgeri. Nas serpentes não parasitadas foram identificadas: B. cepacia, Pseudomonas fluorescens e Acinetobacter baumanii. Nos animais parasitados observaram-se: aumento da concentração de proteína plasmática, diminuição da contagem de linfócitos, e valores normais de hematimetria.


Assuntos
Animais , Bactérias/isolamento & purificação , Parasitos/isolamento & purificação , Pneumopatias Parasitárias/diagnóstico , Pulmão/anatomia & histologia , Pulmão/microbiologia , Pulmão/patologia , Serpentes
18.
Artigo em Inglês | LILACS | ID: lil-492205

RESUMO

Since the nineteenth century ships have been using ballast water (BW) for safety, stability, propulsion and maneuverability, as well as to redress loss of fuel weight and water consumption, and to maintain structural stress at acceptable levels. Ballast water has been spreading many non-native species around the globe, but little is known about the extent and potential significance of ship-mediated transfer of microorganisms. The global movements of ballast water by ships create a long-distance dispersal mechanism for human pathogens that may be important in the worldwide distribution of microorganisms, as well as for the epidemiology of waterborne diseases. Only a few studies have been carried out on this subject, most of them involving ballast water containing crustacean larvae and phytoplankton. Specialized microbiological studies on these waters are necessary to avoid a repeat of what happened in 1991, when epidemic cholera was reported in Peru and rapidly spread through Latin America and Mexico. In July of 1992, Vibrio cholerae was found in the USA and the Food and Drug Administration (FDA) determined that it came from ballast water of ships whose last port of call was in South America. In Brazil, just a few studies about the subject have been performed. An exploratory study by the Brazilian National Health Surveillance Agency (Agência Nacional de Vigilância Sanitária - ANVISA) found in ballast water different microorganisms, such as fecal coliforms, Escherichia coli, Enterococcus faecalis, Clostridium perfringens, coliphages, Vibrio cholerae O1 and Vibrio cholerae non-O1. Until now, Brazil has been focusing only on organisms transported to its territory from other countries by ballast water, to avoid their establishment and dissemination in Brazilian areas. Studies that can assess the probability that water ballast carries pathogenic microorganisms are extremely important, as is the examination of ships that arrive in the country. Treatment of the human...


Assuntos
Cólera/epidemiologia , Saúde Pública , Vibrio cholerae/patogenicidade , Poluição da Água
19.
J. venom. anim. toxins incl. trop. dis ; 14(2): 357-365, 2008. tab
Artigo em Inglês | LILACS | ID: lil-484570

RESUMO

Propolis is a natural resinous substance collected by bees from vegetal sources and its therapeutic properties have been investigated. In this work, we evaluated the inhibitory activity of ethanolic extracts of propolis (EEP) from the Southeast and South of Brazil on coagulase-negative Staphylococcus (CNS) growth as well as the EEP in vitro synergism with antimicrobial drugs by using the diffusion method (E-test). The EEP chemical characteristics (dry weight, pH, flavonoid and phenolic compounds) were determined. Seven drugs were tested, and synergism was observed between three drugs and Southeast EEP, six drugs and South EEP, and one drug and ethanol control. Ethanolic extracts of propolis from the South of Brazil presented the greatest flavonoid content and synergism rate, while EEP from the Southeast presented the greatest anti-CNS activity and phenolic compound content. Results showed the correlation among anti-CNS activity, synergism rate and chemical characteristics of propolis.


Assuntos
Antibacterianos/farmacologia , Coagulase , Própole , Staphylococcus , Brasil , Sinergismo Farmacológico
20.
J. venom. anim. toxins incl. trop. dis ; 11(2): 109-116, May-Aug. 2005. graf
Artigo em Inglês | LILACS, VETINDEX | ID: lil-400104

RESUMO

Propolis antibiotic action has been widely investigated. This assay was carried out in order to observe the in vitro antibacterial activity of propolis against Salmonella enteritidis isolated from food and Salmonella typhimurium isolated from human infections. Propolis was collected by Apis mellifera in two regions of Brazil (Mossoró, Rio Grande do Norte State; and Urubici, Santa Catarina State). Both strains survival percentage decreased with time of incubation in Ethanolic Extracts of Propolis (EEP), demonstrating bactericidal effect after 24 hours. It was also observed that EEP from Mossoró was more effective than that from Urubici. The control of the propolis solvent - 70 percent ethanol - was less effective than EEP, showing only a bacteriostatic effect. We can conclude that propolis shows an activity against Gram-negative bacteria that varies according to the geographical region where it was collected by bees.(AU)


Assuntos
Própole , Salmonella , Salmonella typhimurium , Antibacterianos/análise
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