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1.
Food Sci Technol Int ; 26(1): 11-20, 2020 Jan.
Artículo en Inglés | MEDLINE | ID: mdl-31370696

RESUMEN

Human ingestion of antimicrobial residues in dairy products is a problem of public health. In this study we evaluated antibacterial effectiveness of aqueous and ethanolic leaf extracts of Mangifera indica L. as a natural alternative for reduction of Staphylococcus spp. biofilms. Eight Staphylococcus spp. strains from cows with mastitis and the Staphylococcus aureus strain (ATCC 25923) were evaluated. High performance liquid chromatography indicated the presence of phenolic compounds in the aqueous extract. Agilent Technologies gas chromatography revealed the presence of phenolic compounds, carbohydrates, and gallic acid in ethanolic extract. The tannin contents were 2.27 ± 0.01 and 2.67 ± 0.01% for ethanolic extract and aqueous extract, respectively. Extracts were evaluated in agar diffusion test and the size of inhibition zones were compared. The ethanolic extract was the most effective, showing minimum inhibitory concentrations and minimum bactericidal concentrations between 1.8-7.5 and 15.1-45.3 mg/ml, respectively. After tannin removal, the extracts were less effective, indicating these secondary metabolites as one of the main antibacterial compounds. The ethanolic extract at 45.3 mg/ml reduced mature biofilms in teat rubber (average: 3.91 log reduction) and stainless steel (average: 3.87 log reduction) after 5 min of contact. The extracts of M. indica leaves represent natural alternatives against Staphylococcus spp. strains and the ethanolic extract shows potential as a natural sanitizer.


Asunto(s)
Antibacterianos/farmacología , Biopelículas/efectos de los fármacos , Mangifera/química , Extractos Vegetales/farmacología , Staphylococcus/efectos de los fármacos , Animales , Bovinos , Equipos y Suministros/microbiología , Femenino , Mastitis Bovina/microbiología , Pruebas de Sensibilidad Microbiana , Hojas de la Planta/química , Goma , Acero Inoxidable , Infecciones Estafilocócicas/microbiología , Taninos/análisis
2.
Pesqui. vet. bras ; 37(8): 840-846, Aug. 2017. tab, graf, ilus
Artículo en Inglés | LILACS, VETINDEX | ID: biblio-895496

RESUMEN

This study evaluated the antimicrobial activity and acute or chronic toxicity of the extract of Stryphnodendron adstringens. The stem bark dry extract was obtained by static maceration with ethanol. Quantification of tannins was performed by the Folin-Denis method, which indicated a total tannin content of 32.7%. The antimicrobial activity of the dry extract of S. adstringens was evaluated by agar-based disk diffusion assay with Escherichia coli (ATCC 25922) and Staphylococcus aureus (ATCC 25923) in the concentration of 200, 400 and 600µL/mL. The results indicated that 600µL/mL inhibited microbial growth, i.e. had antimicrobial activity against these species. Acute and chronic toxic effects of S. adstringens was evaluated in Wistar rats treated with 200, 400, 600 and 800mg/kg of extract, administrated by gavage. Liver degeneration was observed in the group of rats receiving 800mg/kg in chronic exposure, what may indicate some degree of toxicity at this concentration. However, no systemic toxicity was observed at lower doses. Considering the broad use of S. adstringens as a phytotherapeutic agent for various human and animal diseases and the livertoxicity observed at high concentrations, attention should be paid to the possible adverse effect of using the extract from this plant at high concentration.(AU)


Avaliou-se neste estudo a atividade antimicrobiana e a toxicidades aguda e crônica do extrato da entrecasca de Stryphnodendron adstringens. A partir do extrato seco, obtido através da maceração estática da casca do caule em etanol de cereais, foi realizada a quantificação de taninos totais (32,7%) pelo método de Folin-Denis. A atividade antimicrobiana do extrato seco extraído de cascas do caule de S. adstringens foi avaliada pela técnica de disco-difusão para os micro-organismos Escherichia coli (ATCC 25922) e Staphylococcus aureus (ATCC 25923) nas concentrações de 200, 400 e 600µL/mL. Os testes de concentração inibitória mínima revelaram que 600µL/mL inibiu o crescimento dos dois micro-organismos testados; o mesmo resultado foi observado para atividade bactericida na concentração de 600µL/mL sobre essas espécies. Efeitos tóxicos sistêmicos agudos e crônicos do extrato seco de S. adstringens administrados por gavagem foram estudados em ratos Wistar, utilizando as doses de 400, 600 e 800mg/kg. Foi observada degeneração hepática no grupo de animais que receberam 800mg/kg tanto no estudo da toxicidade aguda quanto crônica, que pode indicar algum grau de toxicidade de S. adstringens nessa concentração. Considerando o amplo uso de S. adstringens como fitoterápico para humanos e animais, atenção deve ser dispensada para ingestão em altas doses mediante os efeitos tóxicos observados neste estudo.(AU)


Asunto(s)
Animales , Ratas , Ratas Wistar/metabolismo , Fabaceae/efectos adversos , Fabaceae/toxicidad , Antiinfecciosos/toxicidad , Staphylococcus , Taninos , Extractos Vegetales/análisis , Escherichia coli , Enfermedad Hepática Inducida por Sustancias y Drogas/veterinaria
4.
Diagn Microbiol Infect Dis ; 83(4): 375-6, 2015 Dec.
Artículo en Inglés | MEDLINE | ID: mdl-26458280

RESUMEN

Few reports described the presence of bla(KPC) and qnr genes in the same isolate. This study reports the combination of bla(KPC-2) and qnrB19 genes in Klebsiella pneumoniae ST340 isolate in Brazil. These findings draw attention to this combination in ST340 isolate, which is part of the CC258, disseminated in Latin America.


Asunto(s)
Proteínas Bacterianas/metabolismo , Farmacorresistencia Bacteriana Múltiple , Infecciones por Klebsiella/microbiología , Klebsiella pneumoniae/enzimología , beta-Lactamasas/metabolismo , Proteínas Bacterianas/genética , Brasil , Humanos , Klebsiella pneumoniae/genética , Klebsiella pneumoniae/aislamiento & purificación , Masculino , Persona de Mediana Edad , beta-Lactamasas/genética
5.
Pesqui. vet. bras ; 34(12): 1153-1161, dez. 2014. graf, tab
Artículo en Inglés | LILACS | ID: lil-736044

RESUMEN

Currently, there is a growing interest in medicinal plants, because of an increased demand for alternate therapies. In this study, the antimicrobial activity and toxicity of the essential oil of Lippia origanoides (L. origanoides) were investigated. The essential oil of L. origanoides was extracted by steam-dragging distillation and its constituents were identified by chromatography coupled with mass spectrometry. Among the 15 compounds identified, the most abundant were carvacrol (29.00%), o-cymene (25.57%), and thymol methyl ether (11.50%). The essential oil was studied in antimicrobial assays to determine the MIC and MBC. The results indicated that a concentration of 120μL/mL of oil was sufficient to inhibit the growth of the following microorganisms: Escherichia coli (ATCC 25922), Staphylococcus aureus (ATCC 25923) and Salmonella cholerasuis (ATCC 10708). Acute and chronic toxic effects of orally administered oil were investigated in Wistar rats by using standard methods. Doses of 30, 60 and 120mg/kg of the essential oil did not induce significant changes in weight, behavior or hematological and biochemical parameters in the animals. There were no signs of any histopathological changes to the liver, kidneys or heart of the treated rats, suggesting that Lippia origanoides oil is non-toxic after oral administration in acute or chronic toxicity studies. The results obtained in this study show that the essential oil of L. origanoides has a high safety margin, with no detectable toxic effects in rats treated with doses to 120mg/kg. In addition, L. origanoides oil demonstrated potent antimicrobial activity against S. aureus, E. coli and S. cholerasuis. Based on these findings, this essential oil may have practical application as a veterinary antimicrobial.


Atualmente nota-se um aumento do interesse pelas plantas medicinais, fruto da grande procura por terapias alternativas. Neste trabalho foi avaliada a atividade antimicrobiana e a toxicidade do óleo essencial da Lippia origanoides (alecrim-pimenta). O óleo essencial de alecrim-pimenta foi obtido por arraste com vapor d’água e seus constituintes foram identificados por cromatografia acoplada a espectrofotômetro de massa (GC/MS). Entre os 15 compostos identificados os mais abundantes foram o carvacrol (29%), o-cimeno (25,57%) e metil timol éter (11,50%). Os óleos foram submetidos a ensaios antimicrobianos para determinação da CIM e da CBM. Os resultados mostraram que a dose de 120μl/mL de qualquer um dos óleos testados foi eficiente em inibir o crescimento dos micro-organismos Escherichia coli (ATCC 25922), Staphylococcus aureus (ATCC 25923) e Salmonella cholerasuis (ATTCC 10708). Os efeitos tóxicos agudos e crônicos foram verificados em animais segundo método de classes - Toxicidade aguda oral (dose fixas) - OECD 420. As concentrações de 30, 60 e 120 mg/kg de óleo essencial não induziram alterações significativas no peso, no comportamento dos animais e nem nos parâmetros hematológicos e bioquímicos. Também não houve presença de alterações histopatológicas no fígado, rins e coração sugerindo que o óleo de alecrim-pimenta é atóxico após administração oral em condições agudas ou crônicas. Os resultados obtidos neste trabalho levam a concluir que o óleo essencial de alecrim-pimenta possui uma margem elevada de segurança, com efeitos tóxicos inexistentes além de apresentar atividade antimicrobiana eficaz contra os micro-organimos S. aureus, E. coli e S. cholerasuis. Sua utilização na medicina veterinária deve ser considerada como uma grande viabilidade econômica e sustentável.


Asunto(s)
Animales , Lippia/efectos adversos , Lippia/microbiología , Lippia/química
6.
Antimicrob Agents Chemother ; 57(8): 4077-8, 2013 Aug.
Artículo en Inglés | MEDLINE | ID: mdl-23752512

RESUMEN

The present work reports the detection of the first case of nosocomial Klebsiella oxytoca producing class A carbapenemase KPC-2 in Brazil. The isolate KPN106 carried a 65-kb IncW-type plasmid that harbors the blaKPC gene and Tn4401b. Moreover, we detected the presence of a class 1 integron containing a new allele, arr-8, followed by a 5'-truncated dhfrIIIc gene. In view of the recent results, we emphasize the high variability of the bacterial and genetic hosts of this resistance determinant.


Asunto(s)
Genes Bacterianos , Klebsiella oxytoca/enzimología , beta-Lactamasas/genética , Anciano , Alelos , Brasil , Elementos Transponibles de ADN , ADN Bacteriano/genética , Farmacorresistencia Bacteriana , Resultado Fatal , Femenino , Variación Genética , Humanos , Integrones , Infecciones por Klebsiella/diagnóstico , Infecciones por Klebsiella/tratamiento farmacológico , Klebsiella oxytoca/efectos de los fármacos , Klebsiella oxytoca/genética , Klebsiella oxytoca/aislamiento & purificación , Pruebas de Sensibilidad Microbiana , Plásmidos/genética , Plásmidos/metabolismo , Polimixina B/farmacología , Rifampin/farmacología
7.
Pesqui. vet. bras ; 32(6): 490-494, jun. 2012. tab
Artículo en Portugués | LILACS | ID: lil-626492

RESUMEN

A ocorrência de miíases cutâneas foi verificada em 10 diferentes criatórios de ovinos no norte de Minas Gerais, Brasil, durante o período de um ano, onde foram analisados os fatores relacionados a essas parasitoses. Os rebanhos possuíam predominantemente animais mestiços Santa Inês, criados em sistemas semiextensivo. Foram registrados 50 casos e a maior incidência foi observada nos meses de março (22%) e abril (18%), períodos de maiores temperaturas e umidade relativa do ar. As patas foram as regiões mais frequentemente acometidas (34% dos casos). As lesões por pododermatites (38% dos casos), onfaloflebites (10%), linfadenite (6%) e dermatobiose (6%) foram os fatores mais frequentemente relacionados às miíases. As taxas de ocorrência não diferiram quanto ao sexo e idade dos animais. Foi constatado que a maioria dos proprietários não realizava o tratamento das miíases de forma correta, sendo que após a implantação de uma terapia preconizada nesta pesquisa, 92% das lesões apresentaram cura entre sete e trinta dias. Os resultados apontam a importância de estratégias para prevenção baseadas nos fatores relacionados neste estudo. A inspeção constante dos ovinos, identificando-se os ferimentos e tratando-se as lesões precocemente, devem constituir práticas rotineiras, principalmente no período chuvoso e quando estão presentes nas patas dos animais.


Cutaneous myiasis was investigated in 10 sheep herds during one year in northern Minas Gerais, Brazil, and factors related to its occurrence were analyzed. The sheep were predominantly hybrid Saint Inês, bred in semi-extensive systems. A total of 50 cases were registered and the highest incidence occurred during March (22%) and April (18%), months with high temperatures and high relative humidity of the air. There was no influence of sex and age for the occurrence of myiasis. The lesions were mostly found on the legs (34% of the cases). Pododermatitis (38% of the cases), omphalophlebitis (10%), lymphadenitis (6%) and dermatobiosis (6%) were the predisposing factors more frequently associated with myiasis. The myiasis was not correctly treated by the owners, but after implantation of a correct therapy, 92% of the lesions presented cure within 7 to 30 days. The results show the importance of preventive strategies based on the predisposing factors identified in this study. The constant inspection, identifying wounds and precociously treating the lesions, should be routine especially at the end of rainy season and when predisposing factors are present.


Asunto(s)
Animales , Causalidad , Dípteros/parasitología , Infección por Gusano Barrenador/veterinaria , Miasis/prevención & control , Miasis/veterinaria , Ovinos/parasitología , Estaciones del Año , Panadizo Interdigital , Hipodermosis/veterinaria , Ivermectina/uso terapéutico , Linfadenitis/parasitología , Ombligo/parasitología
8.
Antimicrob Agents Chemother ; 56(4): 2205-6, 2012 Apr.
Artículo en Inglés | MEDLINE | ID: mdl-22290946

RESUMEN

This work reports the identification of the first case of a KΡC-2-producing Pseudomonas putida isolate (PP36) in Brazil. The PP36 isolate was resistant to all the antimicrobials tested except polymyxin B. In addition to the discovered bla(KPC-2) gene, genetic analysis showed the presence of a class 1 integron containing the dhfrXVb gene and the new allele arr-6, which codes for resistance to rifampin. These elements were found in an IncFI 65-kb plasmid.


Asunto(s)
Pseudomonas putida/metabolismo , beta-Lactamasas/biosíntesis , Alelos , Antibacterianos/uso terapéutico , Brasil , Linfoma de Burkitt/complicaciones , Linfoma de Burkitt/tratamiento farmacológico , Niño , Humanos , Integrones/genética , Masculino , Meropenem , Pruebas de Sensibilidad Microbiana , Datos de Secuencia Molecular , Plásmidos/genética , Reacción en Cadena de la Polimerasa , Infecciones por Pseudomonas/tratamiento farmacológico , Infecciones por Pseudomonas/microbiología , Pseudomonas putida/genética , Tienamicinas/uso terapéutico , beta-Lactamasas/genética
9.
Vet Immunol Immunopathol ; 138(1-2): 129-33, 2010 Nov 15.
Artículo en Inglés | MEDLINE | ID: mdl-20709411

RESUMEN

The aim of the present study was to evaluate and standardize the ToBI test in vitro as a substitute for the serum neutralization test in mice for quality control of clostridial vaccines. The ToBI test in vitro was used to evaluate 40 serum samples of known antibody content, obtained from rabbits immunized against clostridiosis with experimental vaccine. The correlation between epsilon antitoxin titers in rabbit sera, determined by the ToBI test and serum neutralization in mice, ranged from 0.222% to 0.452% in polyvalent vaccines and from 0.154% to 0.387% in monovalent vaccines. Interplate coefficients of variation were not significant, reaching 0.350% in polyvalent vaccines and 0.400% in monovalent vaccines, indicating high homogeneity. In conclusion, the ToBI test in vitro is suitable for assessing the potency of clostridial vaccines and may be used as an alternative method able to replace current in vivo tests.


Asunto(s)
Antitoxinas/sangre , Toxinas Bacterianas/antagonistas & inhibidores , Clostridium perfringens/inmunología , Pruebas Serológicas/métodos , Animales , Toxinas Bacterianas/inmunología , Vacunas Bacterianas/inmunología , Vacunas Bacterianas/normas , Infecciones por Clostridium/diagnóstico , Infecciones por Clostridium/inmunología , Infecciones por Clostridium/prevención & control , Enterotoxemia/diagnóstico , Enterotoxemia/inmunología , Enterotoxemia/prevención & control , Inmunización , Técnicas In Vitro , Ratones , Pruebas de Neutralización/métodos , Control de Calidad , Conejos , Pruebas Serológicas/normas
10.
Artículo en Inglés | Sec. Est. Saúde SP, SESSP-IBPROD, Sec. Est. Saúde SP, SESSP-IBACERVO | ID: biblio-1068396

RESUMEN

The aim of the present study was to evaluate and standardize the ToBI test in vitro as a substitute for the serum neutralization test in mice for quality control of clostridial vaccines. The ToBI test in vitro was used to evaluate 40 serum samples of known antibody content, obtained from rabbits immunized against clostridiosis with experimental vaccine. The correlation between epsilon antitoxin titers in rabbit sera, determined by the ToBI test and serum neutralization in mice, ranged from 0.222% to 0.452% in polyvalent vaccines and from 0.154% to 0.387% in monovalent vaccines. Interplate coefficients of variation were not significant, reaching 0.350% in polyvalent vaccines and 0.400% in monovalent vaccines, indicating high homogeneity. In conclusion, the ToBI test in vitro is suitable for assessing the potency of clostridial vaccines and may be used as an alternative method able to replace current in vivo tests.


Asunto(s)
Animales , Ratones , Conejos , Antitoxinas , Clostridium perfringens , Animales de Laboratorio , Ética en Investigación
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