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Arq. Ciênc. Vet. Zool. UNIPAR (Online) ; 24(2, cont.): e2407, jul-dez. 2021. tab, graf
Article in English | LILACS, VETINDEX | ID: biblio-1352314


The factors that arouse interest in the study of essential oils as biocidal agents are numerous, such as the fact that they have antibacterial, antifungal, insecticidal, antioxidant, anti-inflammatory and larvicidal properties. The objective of this work was to evaluate the antimicrobial activity, in vitro, of the laurel (Laurus nobilis L) essential oil on the growth of pathogenic bacteria Salmonella enterica serovar Typhimurium ATCC 14028 and Staphylococcus aureus ATCC 25923, at different exposure times, as well as to perform the chemical characterization. Twenty compounds were identified and quantified, representing 96.57% of the total composition. The class of oxygenated monoterpenes represented the majority class of the essential oil, with 1,8-cineol (33.8%) as the substance found in greater quantity, followed by linalool (17.79%). The third constituent in greater quantity was sabinene (12.23%), belonging to the group of monoterpene hydrocarbons. Terpinyl acetate (9.41%) was also considered to be quantitatively representative. Laurel essential oil showed bacteriostatic activity against S. Typhimurium ATCC 14028 and S. aureus ATCC 25923.(AU)

Os fatores que despertam interesse no estudo dos óleos essenciais como agentes biocidas são inúmeros, como o fato de possuírem propriedades antibacteriana, antifúngica, inseticida, antioxidante, antiinflamatória e larvicida. O objetivo deste trabalho foi avaliar a atividade antimicrobiana, in vitro, do óleo essencial de louro (Laurus nobilis L) sobre o crescimento das bactérias patogênicas Salmonella enterica sorovar Typhimurium ATCC 14028 e Staphylococcus aureus ATCC 25923, em diferentes tempos de exposição, assim como realizar a caracterização química do óleo. Vinte compostos foram identificados e quantificados, representando 96,57% da composição total. A classe dos monoterpenos oxigenados representou a classe majoritária do óleo essencial, sendo o 1,8-cineol (33,8%) a substância encontrada em maior quantidade, seguido do linalol (17,79%). O terceiro constituinte em maior quantidade foi o sabineno (12,23%), pertencente ao grupo dos hidrocarbonetos monoterpênicos. O acetato de terpinila (9,41%) também foi considerado quantitativamente representativo. O óleo essencial de louro apresentou atividade bacteriostática contra S. Typhimurium ATCC 14028 e S. aureus ATCC 25923.(AU)

Los factores que despiertan interés en el estudio de los aceites esenciales como agentes biocidas son innumerables, como el hecho de que tienen propiedades antibacterianas, anti fúngicas, insecticidas, antioxidantes, antiinflamatorias y larvicidas. El objetivo de este trabajo ha sido evaluar la actividad antimicrobiana, in vitro, del aceite esencial de laurel (Laurus nobilis L) sobre el crecimiento de bacterias patógenas Salmonella enterica serovar Typhimurium ATCC 14028 y Staphylococcus aureus ATCC 25923, en diferentes momentos de exposición, así como realizar la caracterización química del aceite. Se identificaron y cuantificaron veinte compuestos, que representan el 96,57% de la composición total. La clase de mono terpenos oxigenados representó la clase principal de aceite esencial, siendo el 1,8-cineol (33,8%) la sustancia que se encuentra en mayor cantidad, seguida del linalol (17,79%). El tercer constituyente en mayor cantidad fue el sabineno (12,23%), perteneciente al grupo de los hidrocarburos monoterpénicos. El acetato de terpinilo (9,41%) también se consideró cuantitativamente representativo. El aceite esencial de laurel mostró actividad bacteriostática contra S. Typhimurium ATCC 14028 y S. aureus ATCC 25923.(AU)

Staphylococcus aureus , Salmonella enterica , Laurus/chemistry , Antioxidants , In Vitro Techniques , Anti-Bacterial Agents
Alerta (San Salvador) ; 4(3): 175-170, jul. 29, 2021. graf, tab
Article in Spanish | LILACS, BISSAL | ID: biblio-1283003


Introducción. Los patrones de susceptibilidad antimicrobiana de Salmonella enterica serotipo Typhi se han modificado globalmente durante las últimas tres décadas. Objetivo. Describir los patrones de susceptibilidad antimicrobiana de las cepas de Salmonella enterica Typhi, aisladas en El Salvador de enero 2017 a junio 2020. Metodología. Evaluación secundaria de las bases de datos del Laboratorio Nacional de Salud Pública, de los aislamientos de Salmonella enterica Typhi con sus respectivos antibiogramas, de muestras de pacientes que adolecieron de fiebre tifoidea en El Salvador, de enero 2017 a junio 2020. Resultados. 1406 aislamientos de Salmonella enterica Typhi fueron reportados. El 100 % de los aislamientos analizados presentó susceptibilidad a la ceftriaxona y a la azitromicina. El 99,9 % de los aislamientos analizados presentó susceptibilidad a la ampicilina, al cloranfenicol, a la tetraciclina y al trimetoprim-sulfametoxazol. Para ciprofloxacina, se detectó susceptibilidad en el 8,5% de las cepas analizadas, susceptibilidad intermedia en el 91,5% y resistencia en el 0,08 %. Conclusión. Los hallazgos son compatibles con lo reportado a nivel mundial: el desarrollo rápido de susceptibilidad intermedia o resistencia a la ciprofloxacina, una vez esta es adoptada como el tratamiento de elección para la fiebre tifoidea. En El Salvador, los antibióticos antes considerados como de primera línea contra Salmonella enterica Typhi, deben ser reciclados

Introduction. The antimicrobial susceptibility patterns of Salmonella enterica serotype Typhi have been modified globally for the past three decades. Target. Describe the antimicrobial susceptibility patterns of Salmonella enterica Typhi strains, isolated in El Salvador from January 2017 to June 2020. Methodology. Secondary assessment from the databases of the National Public Health Laboratory, of the isolates of Salmonella enterica Typhi with their respective antibiograms, of samples of patients who suffered from typhoid fever in El Salvador, from January 2017 to June 2020. Results. 1406 isolates of Salmonella enterica Typhi were reported. 100% of the isolations analyzed showed susceptibility to ceftriaxone and azithromycin. 99.9% of the isolates analyzed presented susceptibility to ampicillin, chloramphenicol, tetracycline, and trimethoprim-sulfamethoxazole. For ciprofloxacin, detected susceptibility in 8.5% of the strains analyzed, intermediate susceptibility in 91.5% and resistance in the 0.08%. Conclution. The findings are consistent with what has been reported worldwide: the rapid development of susceptibility intermediate or resistance to ciprofloxacin, once it is adopted as the treatment of choice for typhoid fever. In El Salvador, antibiotics previously considered first-line against Salmonella enterica Typhi, must be recycled

Microbial Sensitivity Tests , Salmonella enterica , Laboratories , Public Health , Disease Susceptibility
Braz. J. Pharm. Sci. (Online) ; 57: e19139, 2021. graf
Article in English | LILACS | ID: biblio-1350244


Dehydroepiandrosterone (DHEA) is a steroid hormone secreted by the adrenal glands, gonads and brain. It is a precursor to sex hormones and also is known to have immune modulatory activity. However, little is known about the relationship between DHEA and neutrophils and thus our study evaluates the influence of DHEA in the effector functions of neutrophils. Human neutrophils were treated in vitro with DHEA and further infected with Salmonella enterica serovar Typhimurium. The treatment of neutrophils with 0.01 µM of DHEA increased the phagocytosis of Salmonella independent of TLR4 as the treatment did not modulate the TLR4 expression. Additionally, DHEA caused a decrease in ROS (reactive oxygen species) production and did not influence the formation of the neutrophil extracellular trap (NET). Steroid treated neutrophils, infected or stimulated with LPS (lipopolysaccharide), showed reduced production of IL-8, compared to untreated cells. Also, the protein levels of p-NFκB were decreased in neutrophils treated with DHEA, and this reduction could explain the reduced levels of IL-8. These results led us to conclude that the steroid hormone DHEA has important modulatory functions in neutrophils

Humans , Male , Adult , In Vitro Techniques , Dehydroepiandrosterone/analysis , Neutrophils/metabolism , Phagocytosis/genetics , Gonadal Steroid Hormones/pharmacology , Adrenal Glands/metabolism , Salmonella enterica/classification
Arq. Inst. Biol ; 88: e01052018, 2021. tab
Article in English | LILACS, VETINDEX | ID: biblio-1349026


Ammonium quaternary compounds are widely used in poultry and swine production as disinfectants in the control of pathogens. They act on gram-positive bacteria, gram-negative bacteria, enveloped fungi and viruses. However, in some conditions of pH and presence of organic matter can be inactivated. This study evaluated the action of ammonium quaternary compounds at 1:1,000 and 1:2,000 dilutions against Salmonella enterica serovarTyphimurium and Salmonella enterica serovar Enteritidis in the presence of three different organic matter simulators, fetal bovine serum, skim milk and whole milk concentration of 1, 3, 5, and 7% and at pH 6 and 9, with 15 min of contact. It was possible to verify that the organic matter simulators adjusted in the same conditions of contact time and percentage, in the in vitro tests, presented different results and the fetal bovine serum did not inactivate the disinfectant. However, the best result against S. Typhimurium and S. Enteritidis was obtained at pH 6 at the dilution of 1:1,000 in all organic matter simulators.

Salmonella enteritidis , Containment of Biohazards , Salmonella enterica , Organic Matter , Quaternary Ammonium Compounds , Swine , Birds , In Vitro Techniques , Serum Albumin, Bovine , Milk , Disinfectants , Gram-Negative Bacteria , Gram-Positive Bacteria
Arq. Inst. Biol ; 88: e00402020, 2021. mapas, tab, graf
Article in English | LILACS, VETINDEX | ID: biblio-1349004


The epidemiology of salmonellosis in poultry is complex, which makes it difficult to identify the origin and spread of this disease in poultry farms. The aims of this study were to characterize the spatial distribution of Salmonella enterica in epidemiological units in Paraná, Brazil; and to investigate correlations between this microorganism and associated factors. Among the epidemiological units, 78 of 243 (32.10%) were positive. Spatially, the northwestern and western regions had higher concentrations of positive cases than the other regions. In bivariate analyses, the presence of other animal species in the epidemiological unit (prevalence ratio, PR = 0.64; 95% confidence interval, CI = 0.43­0.95; p = 0.022) and proximity to establishments at risk (PR = 0.51; 95% CI = 0.32­0.81; p = 0.001) did not influence positivity, but the average population per poultry shed (between 30,501 and 32,500; PR = 2.57; 95% CI = 1.72­3.83; p = 0.001) was associated with Salmonella positivity. Multiple logistic regression demonstrated that the average population per poultry shed, presence of surrounding risk-posing establishments and presence of surrounding poultry sheds produced a significant multiple model for S. enterica. The results indicated that the presence of S. enterica may be related to higher density broiler in poultry sheds, presence of surrounding poultry sheds, proximity between positive and negative epidemiological units and altitude of the municipality. The information obtained showed that some factors were related to positivity for this microorganism and emphasizes the importance of serotyping to obtain other epidemiological data.

Poultry , Salmonella Infections/epidemiology , Salmonella enterica , Birds , Serotyping , Retrospective Studies , Prevalence Ratio , Farms
Pesqui. vet. bras ; 40(10): 781-790, Oct. 2020. tab, graf
Article in English | LILACS, VETINDEX | ID: biblio-1143415


The intensification of pig production and advances in the sanitary control of herds profoundly changed the profile of risk attributed to pork consumption. In the actual scenario, most microorganisms related to macroscopic lesions observed in the post mortem inspection are not transmitted by food, while foodborne bacteria of importance to consumer health do not cause macroscopic lesions. In Brazil, the "Ministério da Agricultura, Pecuária e Abastecimento" requested a scientific opinion on the prioritizing of pathogens potentially transmitted by unprocessed pork. After conducting a qualitative risk assessment, only Salmonella enterica was classified as of high risk to consumers. The present study was part of the validation step of the risk assessment and aimed to investigate the frequency of S. enterica, Yersinia enterocolitica and Listeria monocytogenes and hygienic-sanitary indicators in pig carcasses of pigs rose under intensive production and slaughtered under the Federal Inspection System in three slaughterhouses located in Southern Brazil. Additionally, the antimicrobial resistance profile of the isolated pathogens was also investigated. A total of 378 carcasses were sampled by superficial sponges before the chilling step in three slaughterhouses. Samples were investigated for the presence of the three aforementioned pathogens and subjected to enumeration of Colony Formation Units (log of total aerobic mesophiles (TAM) and Enterobacteriaceae. Salmonella strains were tested by disc diffusion test for resistance to eleven antimicrobials. There were significantly statistical differences (p<0.0001) on the median counts of both indicators between the slaughterhouses. The median of TAM was very close for Slaughterhouses A and B: 1.573 log and 1.6014 log, respectively. While in Slaughterhouse C, a higher TAM median was detected (2.216 log A similar profile was observed regarding to Enterobacteriaceae, and medians were calculated as follow: -0.426 log in Slaughterhouse A; 0.2163 log in B; and 0.633 log in C. Regarding the pathogens investigated, L. monocytogenes was not detected and only one carcass from Slaughterhouse C was positive for Y. enterocolitica. Thus, the results suggest a very low prevalence of L. monocytogenes and Y. enterocolitica in the sampled population. A total of 65 (17.2%) carcasses were positive for S. enterica, with a difference in frequencies between slaughterhouses and slaughter days. The prevalence of Salmonella positive carcasses was higher in the Slaughterhouse C (25.4%; CI 95% 19-32%) in comparison with A (9.5%; CI 95% 9-14%) and B (18.3%; CI 95% 12-24%). There was no significantly statistical association between Enterobacteriaceae counts and Salmonella isolation on carcass surface (p=0.69). The slaughtering day, nested within the slaughterhouse, explains 31.3% of Salmonella prevalence variability. S. Typhimurium (38.1%) was the most prevalent, followed by S. Infantis (30.1%). Among the 61 Salmonella strains tested for resistance to antimicrobials, 18 (31.6%) were full-susceptible. No strain displayed resistance to azithromycin, ceftazidime, cefotaxime and meropenem. The highest resistance frequency was displayed to tetracycline (54.1%), followed by ampicillin (50.82%), nalidixic acid (42.62%) and chloramphenicol (42.62). Multi-resistance was detected in 52.54% of the, strains. In conclusion, S. enterica is more prevalent in pre-chill pig carcasses than Y. enterocolitica and L. monocytogenes and thus should be prioritized in monitoring and control programs at slaughter. Salmonella serovars varied among slaughterhouses and present significant differences in their resistance to antimicrobials. Slaughterhouses that present higher medians of TAM or Enterobacteriaceae in a monitoring period may have higher S. enterica prevalences as well. However, there is a high variation of S. enterica prevalence among slaughter days, which cannot be always related to the hygienic indicators counts observed on a given day.(AU)

A intensificação da produção de suínos e os avanços no controle sanitário dos rebanhos alterou de forma importante o perfil de risco do consumo de carne suína. No cenário atual, a maioria dos microrganismos causadores de lesões macroscópicas detectáveis na inspeção post mortem não são transmissíveis por alimentos, enquanto bactérias de importância como causadoras de doenças transmitidas por alimentos não causam lesões macroscópicas. No Brasil, o Ministério da Agricultura, Pecuária e Abastecimento solicitou uma opinião científica sobre a priorização de patógenos potencialmente transmitidos pela carne suína in natura. Após conduzir uma avaliação de risco qualitativa, apenas Salmonella enterica foi classificada como de alto risco para o consumidor. O presente estudo foi parte da etapa de validação da avaliação de risco e objetivou: investigar a frequência de S. enterica, Yersinia enterocolitica e Listeria. monocytogenes; e enumerar indicadores higiênico-sanitários em carcaças de suínos abatidos sob inspeção federal em frigoríficos dedicados ao abate de suínos sob sistema intensivo de criação no sul do Brasil. Além disso, o perfil de resistência a antimicrobianos dos patógenos isolados foi investigado. A superfície de um total de 378 carcaças foi amostrada por esponjas, na etapa de pré-resfriamento em três matadouros frigoríficos (A, B, C). As amostras foram investigadas quanto à presença dos três patógenos acima mencionados e quanto à enumeração de Unidades Formadoras de Colônia (log de mesófilos aeróbios totais (MAT) e Enterobacteriaceae. As cepas isoladas de Salmonella foram testadas quanto à resistência a onze antimicrobianos pela técnica de disco difusão. As medianas de contagem de ambos os indicadores apresentaram diferença significativa (p<0,0001) entre matadouros-frigoríficos. A mediana de MAT foi bastante próxima para A e B (1,573 log e 1,6014 log, respectivamente), enquanto em C uma mediana de MAT mais elevada foi determinada (2,216 log Um perfil semelhante foi observado em relação a Enterobacteriaceae, sendo as medianas calculadas para A, B e C, respectivamente: -0,426 log; 0,2163 log; e 0,633 log Em relação aos patógenos investigados, L. monocytogenes não foi detectada e apenas uma carcaça, do Matadouro C, foi positiva para Y. enterocolitica. Portanto, os resultados sugerem uma prevalência muito baixa desses patógenos na população amostrada. Em um total de 65 (17,2%) carcaças houve isolamento de S. enterica, com diferença nas frequências observadas entre matadouros e dias de abate. A prevalência de carcaças positivas para S. enterica foi maior no Matadouro C (25,4%; IC95% 19-32%) em comparação com A (9,5%; IC95% 9-14%) e B (18,3%; IC95% 12-24%). Não houve associação estatística entre o número de Enterobacteriaceae e o isolamento de S. enterica na superfície das carcaças (p=0,69). O dia de abate agrupado por frigorífico explica 31,3% da variação na prevalência de Salmonella. O sorovar mais frequente de S. enterica foi Typhimurium (38,1%) seguido de S. Infantis (30,1%). Entre as 61 cepas de S. enterica testadas quanto à resistência a antimicrobianos, 18 (31,6%) foram totalmente suscetíveis aos antimicrobianos testados. Nenhuma cepa apresentou resistência a azitromicina, ceftazidima, cefotaxima e meropenem. As maiores frequências de resistência foram demonstradas contra tetraciclina (54,1%), ampicilina (50,8%), ácido nalidíxico (42,62%) e cloranfenicol (42,62%). Em 52,54% das cepas foi detectada multi-resistência. Em conclusão, S. enterica é mais prevalente em carcaças suínas no pré-resfriamento do que Y. enterocolitica e L. monocytogenes. Portanto, S. enterica deve ser priorizada em programas de monitoramento e controle ao abate. Os sorovares de Salmonella variam entre matadouros e apresentam diferenças significativas na resistência a antimicrobianos. Matadouros de suínos que apresentam medianas de MAT e Enterobacteriaceae num período de monitoramento podem apresentar também prevalências mais de altas de presença de S. enterica. Entretanto, há uma alta variabilidade na frequência de S. enterica entre dias de abate, e nem sempre há relação entre essa frequência e a contagem de indicadores higiênico-sanitários determinados num determinado dia.(AU)

Animals , Yersinia enterocolitica/isolation & purification , Salmonella enterica/isolation & purification , Drug Resistance, Bacterial , Pork Meat/microbiology , Listeria monocytogenes/isolation & purification , Abattoirs , Sus scrofa
Rev. chil. infectol ; 37(4): 395-401, ago. 2020. tab, graf
Article in Spanish | LILACS | ID: biblio-1138564


Resumen Introducción: La salmonelosis es una zoonosis universal, causante de frecuentes brotes de enfermedades transmitidas por alimentos; Salmonella enterica es la especie con la mayor prevalencia, describiéndose un aumento progresivo de su resistencia a antimicrobianos. Objetivo: Determinar la frecuencia de serotipos y los patrones de resistencia antimicrobiana en aislados de S. enterica remitidos al Instituto Nacional de Salud, Lima, Perú. Materiales y Métodos: Se realizó un estudio descriptivo, transversal. Se incluyeron en el estudio todas las cepas remitidas como parte de la vigilancia nacional basada en laboratorio entre los años 2012 y 2015. Las cepas fueron confirmadas mediante pruebas convencionales y serotipificadas por el esquema de Kauffmann-White; la susceptibilidad antimicrobiana y la confirmación del fenotipo BLEE se realizó según el método de Kirby-Bauer y método de Jarlier. Resultados: Un total de 540 cepas de S. enterica fueron incluidos en el estudio, de las que 96% (520/540) correspondió a cepas de origen humano y 4% (20/540) de origen no humano (aves, alimentos y ambiental). En muestras humanas, el serovar más frecuente fue S. Infantis (57%), seguido de S. Enteritidis (27%) y S. Typhimurium (6%). Se encontró una alta resistencia a nitrofurantoína (74%), ácido nalidíxico (64%), ciprofloxacina (63%), tetraciclina (63%), ampicilina (56%), cotrimoxazol (56%), cefotaxima (53%) y cloranfenicol (50%). En muestras no humanas, el serotipo más frecuente fue S. Infantis (45%), seguido de S. Typhimurium (40%) y S. Enteritidis (10%). encontrándose una alta resistencia a ciprofloxacina (45%), cotrimoxazol (40%), y tetraciclina (40%). El 65% del total de las cepas presentó resistencia a más de dos antimicrobianos, 43,3% fueron productoras de BLEE y 99% de éstas presentaron resistencia a entre seis y ocho antimicrobianos. Conclusiones: Se encontró una alta frecuencia de Salmonella Infantis productoras de BLEE, con multi-resistencia a los antimicrobianos en los aislados de muestras humanas y no humanas recibidas en el Instituto Nacional de Salud.

Abstract Background: Salmonellosis is a universal zoonosis, causing frequent outbreaks of foodborne illness; Salmonella enterica is the species with the highest prevalence, a progressive increase in its resistance to antimicrobials is described. Aim: To determine the frequency of serovars and antimicrobial resistance patterns in S. enterica isolates submitted to the National Institute of Health, Lima, Peru. Methods: This is a cross-sectional study. All strains referred as part of national laboratory-based surveillance between 2012 and 2015 were included in the study. Strains were confirmed by conventional tests and serotyped by the Kauffmann-White scheme; antimicrobial susceptibility and confirmation of the BLEE phenotype was performed according to the method of Kirby-Bauer and Jarlier's method. Results: A total of 540 strains of S. enterica were included in the study, where 96% (520/540) corresponded to human strains and 4% (20/540) to non-human strains (birds, food and environmental). In human samples, the most frequent serovar was S. Infantis (57%), followed by S. Enteritidis (27%) and S. Typhimurium (6%). High resistance to nitrofurantoin (74%), nalidixic acid (64%), ciprofloxacin (63%), tetracycline (63%), ampicillin (56%), sulfamethoxazole-trimethoprim (56%), cefotaxime (53%) and chloramphenicol (50%) was detected. In non-human samples, the most frequent serotype was S. Infantis (45%), followed by S. Typhimurium (40%) and S. Enteritidis (10%); a high resistance to nalidixic acid (55%), ciprofloxacin (45%), sulfamethoxazole-trimethoprim (40%), nitrofurantoin (40%), tetracycline (40%) was found. 65% of all strains had resistance to more than two antibiotics, 43,3% were ESBL producers and 99% of these had resistance between six and eight antibiotics. Conclusions: We found a high frequency of S. Infantis producing ESBL with multi-resistance to the antimicrobials in human and nonhuman samples received by the National Institute of Health.

Salmonella enterica/drug effects , Peru/epidemiology , Microbial Sensitivity Tests , Cross-Sectional Studies , Drug Resistance, Multiple, Bacterial/drug effects , Serogroup , Anti-Bacterial Agents/pharmacology
Biosci. j. (Online) ; 36(1): 223-234, jan./feb. 2020. tab
Article in English | LILACS | ID: biblio-1049244


The Brazilian flora is known for its vast biodiversity; however, many species have been still little studied regarding to their chemical composition and biological potential. Thus, this study aimed to determine the antimicrobial, antioxidant and acaricidal activity of the extracts of leaves of Zanthoxylum caribaeum L. In addition, phytochemical screening of these extracts was carried out to determine the main classes of secondary metabolites present in Z. caribaeum. Using the Z. caribaeum leaves, aqueous and organic extracts were obtained using the following solvents (ethanol, methanol, hexane, acetone, dichloromethane and ethyl acetate). The antimicrobial activity of extracts was determined by broth microdilution method, and to detect antioxidant activity the method of capturing the free radical 2,2-diphenyl-1-picryl hydrazyl (DPPH) was used. The acaricidal activity of the extracts was tested on Dermanyssus gallinae (De Geer) (Acari: Dermanissidae). Ethanolic and methanolic extracts presented antimicrobial activity for most of the bacterial strains tested, as well as for yeast Candida albicans. The ethanolic extract presented high free radical sequestration potential (71.2%) and antioxidant capacity (the lowest IC50 value - 24.39 µg mL-1). The crude extracts obtained with methanol and acetone were the most promising. In general, phytochemical screening indicated the presence of steroids, flavanones, flavones, flavonols, saponins, tannins, triterpenoids and xanthones.

A flora brasileira é conhecida pela sua vasta biodiversidade, no entanto, muitas espécies ainda são pouco estudadas quanto à composição química e ao potencial biológico. Assim, esse trabalho teve como objetivo determinar a atividade antimicrobiana, antioxidante e acaricida dos extratos vegetais das folhas de Zanthoxylum caribaeum L. Adicionalmente, foi realizada triagem fotoquímica desses extratos para determinar as principais classes de metabólitos secundários presentes em Z. caribaeum. Empregando-se as folhas de Z. caribaeum foram obtidos o extrato aquoso e orgânicos, utilizando os seguintes solventes (etanol, metanol, hexano, acetona, diclorometano e acetato de etila). A atividade antimicrobiana dos extratos foi determinada pelo método de microdiluição em caldo, e para detecção da atividade antioxidante foi empregado o método de captura do radical livre 2,2-difenil-1-picril hidrazil (DPPH). A atividade acaricida dos extratos foi avaliada frente a Dermanyssus gallinae (De Geer) (Acari: Dermanissidae). Os extratos brutos etanólico e metanólico apresentaram atividade antimicrobiana para a maioria das cepas bacterianas testadas, e também para a levedura Candida albicans. O extrato etanólico apresentou elevado potencial de sequestro de radicais livres (71,2%) e o menor valor de IC50 (24,39µg mL-1), revelando, portanto, sua capacidade antioxidante. No que se refere à atividade acaricida, os extratos obtidos com metanol e acetona foram os mais promissores. De modo geral, a triagem fitoquímica indicou a presença de esteroides, flavanonas, flavonas, flavonóis, saponinas, taninos, triterpenóides e xantonas.

Plant Extracts/pharmacology , Zanthoxylum , Acaricides/pharmacology , Anti-Infective Agents/pharmacology , Antioxidants/pharmacology , Plant Extracts/chemistry , Microbial Sensitivity Tests , Plant Leaves , Salmonella enterica/drug effects , Zanthoxylum/chemistry , Mites/drug effects
Braz. arch. biol. technol ; 63: e20180568, 2020. tab, graf
Article in English | LILACS | ID: biblio-1132273


Abstract Sophorolipids are glycolipids that have natural antimicrobial properties and present great potential in the pharmaceutical field. The present study aimed to produce sophorolipids from Candida bombicola using a chicken fat-based medium and evaluate the antimicrobial activity against Gram-negative (Proteus mirabilis, Escherichia coli, Salmonella enterica subsp. enterica) and Gram-positive bacteria (Enterococcus faecium, Staphylococcus aureus and Streptococcus mutans). The production of sophorolipids reached 27.86 g L-1. Based on the structural characterization, 73.55% of the sophorolipids present a mixture of acidic monoacetylated C18:2 and lactonic diacetylated C16:0, and 26.45% were present in the diacetylated C18:1 lactonic form. Bacteria submitted to sophorolipid exposure showed a reduction in viability at doses of 500 μg mL-1 and 2,000 μg mL-1 against Gram-positive and Gram-negative bacteria, respectively. These results suggest that sophorolipids produced in chicken fat medium may be used as antimicrobial agents to prevent or eliminate contamination by different pathogens.

Candida/metabolism , Glycolipids/pharmacology , Enterococcus faecium/drug effects , Gram-Negative Bacteria/drug effects , Anti-Bacterial Agents/pharmacology , Proteus mirabilis/drug effects , Glycolipids/isolation & purification , Salmonella enterica/drug effects , Escherichia coli/drug effects , Anti-Bacterial Agents/isolation & purification
Pesqui. vet. bras ; 39(3): 201-208, Mar. 2019. tab
Article in English | LILACS, VETINDEX | ID: biblio-1002799


This study aimed to verify the presence of members from the Enterobacteriaceae family and determine antimicrobial susceptibility profiles of the isolates in canaries bred in northeastern Brazil; in addition, the presence of diarrheagenic Escherichia coli (DEC) and avian pathogenic Escherichia coli (APEC) was also verified in these birds. Samples were collected during an exhibition organized by the Brazilian Ornithological Federation in July 2015 in Fortaleza, Brazil. A total of 88 fecal samples were collected and submitted to pre-enrichment step using buffered peptone water, followed by enrichment with the following broths: brain-heart infusion, Rappaport-Vassiliadis, and Selenite-Cystine. Subsequently, aliquots were streaked on MacConkey, brilliant green and salmonella-shigella agar plates. Colonies were selected according to morphological characteristics and submitted to biochemical identification and antimicrobial susceptibility tests with disk-diffusion technique. E. coli strains were evaluated for the presence of eight DEC genes and five APEC genes through conventional polymerase chain reaction (PCR) screening. The most frequent species observed were Pantoea agglomerans (25%), Serratia liquefaciens (12.5%), and Enterobacter aerogenes (9.1%). A single rough strain of Salmonella enterica subsp. enterica was identified in one sample (1.1%). High resistance rates to amoxicillin (78.7%) and ampicillin (75.4%) were identified. Polymyxin B (9.8%), gentamycin (6.6%), and enrofloxacin (6.6%) were the most efficient antibiotics. The total number of multidrug-resistant strains (isolates resistant to more than three antimicrobial classes) was 23 (37.7%). Four E. coli strains were tested for the virulence genes, and two were positive for APEC virulence genes: one strain was positive for iutA and the other for hlyF. In conclusion, canaries in northeastern Brazil participating in exhibitions may present Salmonella spp., Escherichia coli and other enterobacteria in the intestinal microbiota with antimicrobial resistance. These results indicate that, although the E. coli strains recovered from canaries in this study have some virulence genes, they still do not fulfill all the requirements to be considered APEC.(AU)

O objetivo deste trabalho foi verificar a presença de enterobactérias e determinar o perfil de sensibilidade aos antimicrobianos dos isolados oriundos de canários belgas criados em cativeiro do Nordeste do Brasil, adicionalmente verificou-se a presença de Escherichia coli diarreiogênicas (DEC) e E. coli patogênica aviária (APEC) nesses animais. A colheita das amostras ocorreu durante uma exposição de canários belgas organizada pela Federação Ornitológica do Brasil (FOB), em julho de 2015, na cidade de Fortaleza, Ceará, Brasil. Um total de 88 amostras de fezes foram coletadas e submetidas a pré-enriquecimento utilizando água peptonada, caldo de enriquecimento Brain Heart Infusion, Rappaport-Vassiliadis e Selenito-Cistina. Fez-se triagem em placas de ágar MacConkey, Verde Brilhante e ágar Salmonella Shigella. As colônias foram selecionadas e submetidas à identificação bioquímica e susceptibilidade antimicrobiana. Estirpes de Escherichia coli foram avaliadas quanto a presença de 8 genes de virulência de DEC e cinco de APEC por reação em cadeia da polimerase convencional (PCR). As enterobactérias encontradas com maior frequência foram Pantoea agglomerans (25%), Serratia liquefaciens (12,5%) e Enterobacter aerogenes (9,1%). Uma única estirpe de Salmonella enterica subsp. enterica (rugosa) esteve presente em um dos isolados (1,1%). Altos percentuais de resistência foram encontrados para dois antibióticos: amoxicilina (78,7%) e ampicilina (75,4%). Polimixina B (9,8%), gentamicina (6,8%) e enrofloxacina (6,5%) foram os antibióticos com melhor eficiência. O total de estirpes multirresistentes (a mais de três classes de antimicrobianos) foi de 23 (37,7%). Das quatro estirpes de E. coli isoladas, duas foram positivas para os genes de APEC, sendo uma estipe para o gene iss e outra para os genes iutA e hlyF. Portanto, canários belgas criados em cativeiro no Brasil que participam de exposições podem apresentar Salmonella spp., Escherichia coli e outras enterobactérias em sua microbiota intestinal com resistência antimicrobiana. Estes resultados indicam que as estirpes de E. coli isoladas de canário belga no presente estudo apresentam alguns, mas não todos, genes de virulência para serem caracterizadas como E. coli patogênica para aves (APEC).(AU)

Animals , Canaries/microbiology , Drug Resistance, Microbial , Salmonella enterica/isolation & purification , Pantoea/isolation & purification , Serratia liquefaciens/isolation & purification , Enterobacteriaceae/isolation & purification , Enterobacteriaceae Infections/veterinary , Escherichia coli/isolation & purification , Virulence , Enterobacter aerogenes/isolation & purification
Rev. Soc. Bras. Med. Trop ; 52: e20180253, 2019.
Article in English | LILACS | ID: biblio-977118


Abstract An eleven-year-old boy presented with fever and hip pain, with limited mobility of the right side of the hip. Computed tomography scan revealed an increased volume of the right coxo-femoral joint, requiring surgical drainage of purulent secretion, from which Salmonella enterica was isolated. After four weeks of treatment with third-generation cephalosporin, he was discharged with a favorable evolution. Invasive disease caused by Salmonella spp represents a small proportion of salmonellosis cases, although it is responsible for greater rates of hospitalization, morbidity and mortality. Children under 5 years, elders over 60 years and immunodeficient patients have greater risk for invasive salmonellosis.

Humans , Child , Salmonella Infections/microbiology , Arthritis, Infectious/microbiology , Salmonella enterica/isolation & purification , Salmonella Infections/diagnosis , Salmonella Infections/drug therapy , Arthritis, Infectious/diagnosis , Arthritis, Infectious/drug therapy
Rev. Soc. Bras. Med. Trop ; 52: e20180285, 2019. tab, graf
Article in English | LILACS | ID: biblio-1041544


Abstract INTRODUCTION Salmonella enterica serovar Panama belongs to the D1 serogroup and is frequently associated with nontyphoidal salmonellosis in humans. This study aimed to characterize isolates collected from Northeast Brazil by phenotypic and molecular methods. METHODS Forty four S. Panama strains were examined for antimicrobial susceptibility, virulence genes, and pulsed field gel electrophoresis (PFGE) types. RESULTS All strains were susceptible to antibiotics (except for streptomycin), presented classical virulence factors, and could be clustered into four groups and 18 pulsotypes. CONCLUSIONS This work calls for continuous surveillance for the emergence of antibiotic resistance and new clones in a geographical area.

Animals , Salmonella enterica/genetics , Virulence Factors/genetics , Genetic Variation , Brazil , Microbial Sensitivity Tests , Electrophoresis, Gel, Pulsed-Field , Salmonella enterica/isolation & purification , Salmonella enterica/drug effects , Salmonella enterica/pathogenicity , Drug Resistance, Multiple, Bacterial , Anti-Bacterial Agents/pharmacology
Arq. Inst. Biol ; 86: e0982018, 2019. tab
Article in English | LILACS, VETINDEX | ID: biblio-1024594


In this study, chitin and chitosan were extracted from Litopenaeus vannamei waste using chemical and microwave methods. Shrimp waste was cleaned, dried and ground sieved to 16, 32 and 60 mesh, and the samples were depigmented, demineralized, and deproteinized. Then, the chitin was submitted to a deacetylation process by 45% NaOH solution under microwave irradiation at 600w, for intermittent 15 min or using 5 pulses of 5 minutes. The study showed that the effectiveness of the particle size of 32 mesh and 6 pulses of 5 min to deacetylation with 92% of degree and chitosan yield (52.2%). The polymer chitosan showed higher antimicrobial activity against to Staphylococcus aureus, Escherichia coli, Salmonella enterica and the yeast Candida sp., respectively. The results indicated the feasibility of the microwave radiation as an attractive method to recover chitin and chitosan from shrimp wastes.(AU)

Neste estudo, a quitina e a quitosana foram extraídas de resíduos de Litopenaeus vannamei utilizando métodos químicos e do micro-ondas. Os resíduos de camarão foram limpos, secos e peneirados a 16, 32 e 60 mesh, e as amostras foram despigmentadas, desmineralizadas e desproteinizadas. Posteriormente, a quitina foi submetida a processo de desacetilação por solução de NaOH a 45% sob irradiação de micro-ondas a 600w, durante 15 min intermitentes ou utilizando 6 pulsos de 5 min. O estudo mostrou eficácia nas partículas com tamanho de 32 mesh e 6 pulsos de 5 minutos, com 92% grau de desacetilação e rendimento de quitosana (52,2%). A atividade antimicrobiana foi para Staphylococcus aureus, Escherichia coli e Salmonella enterica contra a levedura Candida sp., respectivamente. Os resultados indicaram a viabilidade da radiação de micro-ondas como um método atraente para recuperação de quitina e quitosana a partir de resíduos de camarão.(AU)

Chitin , Penaeidae , Chitosan , Anti-Bacterial Agents , Staphylococcus aureus , Salmonella enterica , Escherichia coli , Antifungal Agents
Epidemiology and Health ; : e2019002-2019.
Article in English | WPRIM | ID: wpr-763760


OBJECTIVES: This study aimed to reveal the epidemiologic characteristics of the outbreak of gastroenteritis caused by Salmonella enterica serovar Thompson in Busan Metropolitan City and to identify points for improvement to prevent of food-borne disease outbreak. METHODS: This was a case-control study. The control group comprised asymptomatic students in the same classes of the cases. The presence or absence of symptoms, ingestion of each food provided by school meal service, and commonly ingested foods in addition to those foods in meal service were investigated. Moreover, specimens collected from rectal swab, preserved foods, and environmental surface were tested. RESULTS: Of the 6,092 subjects, 1,111 (1,083 students, 22 school personnel, and 6 foodservice employees) were included in the case group; this corresponded to an 18.4% attack rate. Symptoms included diarrhea (n=1,051, 94.6%), abdominal pain (n=931, 83.8%), febrile sensation (n=502, 45.2%), and vomiting (n=275, 24.8%). The epidemic curves of each 10 schools were unimodal. Investigation of food intake showed a significantly high odds ratio for chocolate cake in 5 out of the 10 schools. Laboratory test detected Salmonella enterica serovar Thompson both in rectal swab specimens of 9 schools and in collected preserved chocolate cakes of 9 schools. Pulsed-field gel electrophoresis test result showed that Salmonella enterica seorvar Thompson isolated from human and foods were the same. CONCLUSIONS: The source of infection for the Salmonella enterica serovar Thompson outbreak in the 10 schools of Busan Metropolitan City is chocolate cake. Traceback investigation for origin of contaminated food in food-borne disease outbreak and safety control during food production should be more enhanced.

Abdominal Pain , Cacao , Case-Control Studies , Diarrhea , Eating , Electrophoresis, Gel, Pulsed-Field , Food, Preserved , Foodborne Diseases , Gastroenteritis , Humans , Korea , Meals , Odds Ratio , Salmonella enterica , Salmonella Infections , Salmonella , Sensation , Serogroup , Vomiting
Article in English | WPRIM | ID: wpr-758893


It is crucial to optimize the dose of fluoroquinolones to avoid antibiotic resistance and to attain clinical success. We undertook this study to optimize the dose of enrofloxacin against Salmonella enterica subsp. enterica serovar Enteritidis (S. Enteritidis) in chicken by assessing its pharmacokinetic/pharmacodynamic (PK/PD) indices. The antibacterial activities of enrofloxacin against S. Enteritidis were evaluated. After administering 10 mg/kg body weight (b.w.) of enrofloxacin to broiler chickens of both sexes by intravenous (IV) and peroral (PO) routes, blood samples were drawn at different intervals and enrofloxacin concentrations in plasma were determined. PK/PD indices were calculated by integrating the PK and PD data. The elimination half-lives (T(1/2)), time required to reach peak concentration (T(max)), peak concentration (C(max)), and area under curve (AUC) after administering enrofloxacin by PO and IV routes were 25.84 ± 1.40 h, 0.65 ± 0.12 h, 3.82 ± 0.59 µg/mL, and 20.84 ± 5.0 µg·h/mL, and 12.84 ± 1.4 h, 0.22 ± 0.1 h, 6.74 ± 0.03 µg/mL, and 21.13 ± 0.9 µg.h/mL, respectively. The bioavailability of enrofloxacin was 98.6% ± 8.9% after PO administration. The MICs of enrofloxacin were 0.0625–1 µg/mL against S. Enteritidis strains, and the MIC₅₀ was 0.50 µg/mL. The C(max)/MIC₅₀ were 7.64 ± 0.2 and 13.48 ± 0.7 and the 24 h AUC/MIC₅₀ were 41.68 ± 0.1 and 42.26 ± 0.3 after administering the drug through PO and IV routes, respectively. The data in this study indicate that the application of 50 mg/kg b.w. of enrofloxacin to chicken through PO and IV routes with a dosing interval of 24 h can effectively cure S. Enteritidis infection, indicating the need for a 5-fold increase in the recommended dosage of enrofloxacin in chicken.

Area Under Curve , Biological Availability , Body Weight , Chickens , Drug Resistance, Microbial , Fluoroquinolones , Pharmacokinetics , Plasma , Salmonella enterica , Salmonella enteritidis , Salmonella , Serogroup
Epidemiology and Health ; : 2019002-2019.
Article in English | WPRIM | ID: wpr-785784


OBJECTIVES: This study aimed to reveal the epidemiologic characteristics of the outbreak of gastroenteritis caused by Salmonella enterica serovar Thompson in Busan Metropolitan City and to identify points for improvement to prevent of food-borne disease outbreak.METHODS: This was a case-control study. The control group comprised asymptomatic students in the same classes of the cases. The presence or absence of symptoms, ingestion of each food provided by school meal service, and commonly ingested foods in addition to those foods in meal service were investigated. Moreover, specimens collected from rectal swab, preserved foods, and environmental surface were tested.RESULTS: Of the 6,092 subjects, 1,111 (1,083 students, 22 school personnel, and 6 foodservice employees) were included in the case group; this corresponded to an 18.4% attack rate. Symptoms included diarrhea (n=1,051, 94.6%), abdominal pain (n=931, 83.8%), febrile sensation (n=502, 45.2%), and vomiting (n=275, 24.8%). The epidemic curves of each 10 schools were unimodal. Investigation of food intake showed a significantly high odds ratio for chocolate cake in 5 out of the 10 schools. Laboratory test detected Salmonella enterica serovar Thompson both in rectal swab specimens of 9 schools and in collected preserved chocolate cakes of 9 schools. Pulsed-field gel electrophoresis test result showed that Salmonella enterica seorvar Thompson isolated from human and foods were the same.CONCLUSIONS: The source of infection for the Salmonella enterica serovar Thompson outbreak in the 10 schools of Busan Metropolitan City is chocolate cake. Traceback investigation for origin of contaminated food in food-borne disease outbreak and safety control during food production should be more enhanced.

Abdominal Pain , Cacao , Case-Control Studies , Diarrhea , Eating , Electrophoresis, Gel, Pulsed-Field , Food, Preserved , Foodborne Diseases , Gastroenteritis , Humans , Korea , Meals , Odds Ratio , Salmonella enterica , Salmonella Infections , Salmonella , Sensation , Serogroup , Vomiting
Pesqui. vet. bras ; 38(11): 2150-2154, Nov. 2018. tab
Article in English | LILACS, VETINDEX | ID: biblio-976397


This study aimed to isolate Escherichia coli and Salmonella enterica from captured feral pigeons in Fortaleza, Brazil, and, in addition to evaluate the antimicrobial susceptibility profiles and diagnose diarrheagenic E. coli strains. Pigeons were captured in four public locations in Fortaleza with three techniques. Individual cloacal swab samples were collected and submitted to bacterial isolation, biochemical identification and antimicrobial susceptibility test. Disk diffusion technique was used with twelve antibiotics. E. coli strains were submitted to DNA extraction followed by PCR to diagnose five diarrheagenic pathotypes. A total of 124 birds were captured. One bird was positive for Salmonella enterica (0.81%) and 121 (97.58%) were positive for E. coli. Among these, 110 isolates were submitted to antimicrobial susceptibility test and 28.18% (31/110) presented resistance to at least one antibiotic. Resistance to azithromycin was the most frequent (21.82%), followed by tetracycline (10.91%) and sulfamethoxazole with trimethoprim (8.9%). Multidrug resistance, calculated as a resistance to at least 3 antimicrobial classes, was identified in 3.64% (4/110) of strains. The maximum number of antimicrobial classes to which one strain was resistant was seven. Results demonstrated nine different resistance profiles and the most frequent was tetracycline and sulfamethoxazole with trimethoprim (4 strains), followed by chloramphenicol, azithromycin, tetracycline and sulfamethoxazole with trimethoprim (3 strains). Amoxicillin with clavulanic acid and tobramycin presented lowest levels of antimicrobial resistance, to which none of the tested strains were resistant. A single strain was positive for the eltB gene, which is a diagnostic tool to identify the Enterotoxigenic E. coli (ETEC) pathotype. None of the other investigated genes (stx1, stx2, estA, eaeA, ipaH, aatA and aaiC) were identified. The single isolate of S. enterica was a rough strain of Salmonella enterica subsp. enterica, but serotype identification was not possible. However, this isolate presented resistance to amoxicillin, amoxicillin with clavulanic acid, tetracycline and sulfamethoxazole with trimethoprim. Therefore, captured feral pigeons of Fortaleza presented a low prevalence of S. enterica and diarrheagenic E. coli. Considering the investigated pathogens, our results suggest a good health status and a low public health risk. However, important antimicrobial resistance profiles were identified.(AU)

O objetivo deste estudo foi isolar cepas de Escherichia coli e Salmonella enterica de pombos urbanos capturados em Fortaleza, Brasil, e avaliar os perfis de resistência antimicrobiana dos isolados, bem como diagnosticar patotipos diarreiogênicos de E. coli. Pombos foram capturados em quatro locais públicos de Fortaleza utilizando três técnicas. Amostras individuais de suabes cloacais foram coletadas e submetidas a isolamento bacteriano, seguido de identificação bioquímica e teste de susceptibilidade a antimicrobianos. A técnica de disco difusão foi utilizada para avaliar resistência antimicrobiana a doze antibióticos. Cepas de E. coli foram submetidas à extração de DNA seguido de PCR para o diagnóstico de cinco patotipos diarreiogênicos. Um total de 124 aves foram capturadas, a partir das quais em uma houve isolamento de Salmonella enterica (0,81%) e em 121 (97,58%) houve isolamento de E. coli. Destas, 110 isolados foram submetidos a teste de suscetibilidade a antimicrobianos e 28,18% (31/110) apresentaram resistência a pelo menos um antibiótico. Resistência a azitromicina foi a mais frequente (21,82%), seguida por tetraciclina (10,91%) e sulfametoxazol com trimetoprim (8,9%). Resistência a múltiplas drogas foi identificada em 3,64% (4/110) dos isolados e o número máximo de antibióticos aos quais uma única cepa foi resistente foi sete. Resultados demonstraram nove diferentes perfis de resistência e o mais frequente foi tetraciclina e sulfametoxazol com trimetoprim (4 cepas), seguido por cloranfenicol, azitromicina, tetraciclina e sulfametoxazol com trimetoprim (3 cepas). Amoxicilina com ácido clavulânico e tobramicina foram os antibióticos com menor resistência antimicrobiana, aos quais nenhuma cepa apresentou resistência. Uma única cepa foi positiva para o gene eltB que é usado para diagnóstico do patotipo E. coli enterotoxigênica (ETEC), enquanto que os demais genes investigados (stx1, stx2, estA, eaeA, ipaH, aatA e aaiC) não foram identificados. A única cepa de S. enterica isolada foi identificada como uma cepa rugosa de Salmonella enterica subsp. enterica e, portanto, a identificação do sorotipo não foi possível. Entretanto, este isolado apresentou resistência a amoxicilina, amoxicilina com ácido clavulânico, tetraciclina e sulfametoxazol com trimetoprim. Portanto, pombos urbanos capturados em Fortaleza apresentaram baixa prevalência de cepas de S. enterica e E. coli diarreiogênicas. Considerando os patógenos investigados, os resultados encontrados sugerem um bom status sanitário destas aves e um baixo risco à saúde pública. Entretanto, importantes perfis de resistência antimicrobiana foram identificados.(AU)

Animals , Columbidae/microbiology , Drug Resistance, Microbial , Salmonella enterica/isolation & purification , Escherichia coli/isolation & purification
Braz. j. microbiol ; 49(3): 559-563, July-Sept. 2018. tab
Article in English | LILACS | ID: biblio-951811


Abstract The growth of the population of cattle egrets (Bubulcus ibis) in the archipelago of Fernando de Noronha constitutes a threat to public health and biological diversity because of their competition with and predation on native species and the possibility of transmission of pathogens to human beings, livestock and native wildlife. The aim here was to search for, isolate and identify serovars of Salmonella in clinically healthy local cattle egrets. Cloacal swabs were obtained from 456 clinically healthy cattle egrets of both sexes and a variety of ages. The swabs were divided into 51 pools. Six of these (11.7%) presented four serovars of Salmonella enterica subspecies enterica: Salmonella serovar Typhimurium; Salmonella serovar Newport; Salmonella serovar Duisburg; and Salmonella serovar Zega. One sample was identified as S. enterica subspecies enterica O16:y:-. Results in this study suggest that cattle egrets may be reservoirs of this agent on Fernando de Noronha and represent a risk to public health and biological diversity.

Animals , Male , Female , Salmonella Infections, Animal/microbiology , Bird Diseases/microbiology , Salmonella enterica/isolation & purification , Phylogeny , Birds/microbiology , Brazil , Salmonella enterica/classification , Salmonella enterica/genetics
Braz. j. microbiol ; 49(3): 601-606, July-Sept. 2018. tab, graf
Article in English | LILACS | ID: biblio-951806


Abstract Salmonella Gallinarum is a host-restrict pathogen that causes fowl typhoid, a severe systemic disease that is one of the major concerns to the poultry industry worldwide. When infecting the bird, SG makes use of evasion mechanisms to survive and to replicate within macrophages. In this context, phoPQ genes encode a two-component regulatory system (PhoPQ) that regulates virulence genes responsible for adaptation of Salmonella spp. to antimicrobial factors such as low pH, antimicrobial peptides and deprivation of bivalent cations. The role of the mentioned genes to SG remains to be investigated. In the present study a phoPQ-depleted SG strain (SG ΔphoPQ) was constructed and its virulence assessed in twenty-day-old laying hens susceptible to fowl typhoid. SG ΔphoPQ did cause neither clinical signs nor mortality in birds orally challenged, being non-pathogenic. Furthermore, this strain was not recovered from livers or spleens. On the other hand, chickens challenged subcutaneously with the mutant strain had discreet to moderate pathological changes and also low bacterial counts in liver and spleen tissues. These findings show that SG ΔphoPQ is attenuated to susceptible chickens and suggest that these genes are important during chicken infection by SG.

Animals , Female , Poultry Diseases/microbiology , Salmonella Infections, Animal/microbiology , Bacterial Proteins/genetics , Salmonella enterica/metabolism , Salmonella enterica/pathogenicity , Gene Silencing , Poultry Diseases/pathology , Salmonella Infections, Animal/pathology , Spleen/microbiology , Spleen/pathology , Bacterial Proteins/metabolism , Virulence , Chickens , Salmonella enterica/genetics
Pesqui. vet. bras ; 38(7): 1300-1306, July 2018. ilus
Article in English | LILACS, VETINDEX | ID: biblio-976436


Salmonella detection is a key point in food safety testing, because of the frequent association of this pathogen with food poisoning in humans. The standard bacteriological tests currently used for Salmonella-detection are time-consuming; therefore, there is a need to develop alternative methods to accelerate the detection. In order to accelerate Salmonella diagnosis, we used the immunomagnetic separation assay associated with bacteriophage P22 for the rapid detection of the following Salmonella serovars in chicken rinses of drumsticks, artificially contaminated with 5, 10, and 100 CFU/25mL of bacteria: Salmonella enterica subsp. enterica serovar Heidelberg (S. Heidelberg), Salmonella enterica subsp. enterica serovar Enteritidis (S. Enteritidis) and Salmonella enterica subsp. enterica serovar Typhimurium (S. Typhimurium). The efficiency of the technique, represented by the time required for detection of positive and negative samples, was compared with that of the standard diagnostic tests used for this pathogen, the bacteriological assay and the polymerase chain reaction (PCR)-based test. This study confirmed the ability of the bacteriophage-associated immunomagnetic separation assay to identify 99.6% of Salmonella-positive samples of the three serovars tested. In contrast, the bacteriological assay and PCR-based test detected 95.1% and 98.5% of the Salmonella-positive samples respectively.(AU)

A detecção de Salmonella é um ponto crucial para a segurança alimentar, devido a frequente associação deste patógeno com infecções alimentares em humanos. O método padrão para detecção de Salmonella é o bacteriológico, mas o tempo requerido para o processamento das amostras e o diagnóstico final é longo, por isso existe a necessidade de desenvolvimento de métodos alternativos que visem acelerar esta etapa. Para isto utilizamos a separação imunomagnética associada ao bacteriófago P22 como técnica de detecção rápida para os seguintes sorovares de Salmonella: Salmonella enterica subsp. enterica sorovar Heidelberg (S. Heidelberg), Salmonella enterica subsp. enterica sorovar Enteritidis (S. Enteritidis) e Salmonella enterica subsp. enterica sorovar Typhimurium (S. Typhimurium), os quais foram inoculados artificialmente em lavados de sobre-coxas de frango nas seguintes concentrações: 5, 10 e 100 UFC/25mL. A eficiência da técnica, representada pelo tempo requerido para detecção de amostras positivas ou negativas, foi comparado com os testes rotineiramente utilizados para detecção de Salmonella, o exame bacteriológico e a reação em cadeia da polimerase (PCR). Este estudo confirmou a capacidade do teste de separação imunomagnética associado a bacteriófago, o qual identificou 99,6% das amostras positivas para Salmonella, dos três sorovares testados. Já o bacteriológico e PCR identificaram respectivamente 95,1% e 98,5% das amostras positivas.(AU)

Animals , Poultry/microbiology , Salmonella enterica/pathogenicity , Diagnostic Techniques and Procedures/veterinary