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1.
Pesqui. vet. bras ; 41: e06696, 2021. tab
Article in English | ID: biblio-1340354

ABSTRACT

The grey-breasted parakeet (Pyrrhura griseipectus) is an endangered psittacine species that have been affected by illegal trade and deforestation. Currently, this endemic species is only found in three areas in Ceará state, in Brazil. This study aimed to investigate the frequency and diversity of Enterobacteriaceae in wild adult grey-breasted parakeets and determine their susceptibility to antimicrobial agents. Cloacal swab samples were collected from 27 individuals and environmental swabs (drag swabs) from five nests used by these birds. Twenty-seven strains from nine species of Enterobacteriaceae were recovered from cloacal swabs, and the most prevalent bacteria strains were Hafnia alvei (22%) and Pantoea agglomerans (22%). From environmental nest samples, seven strains from three bacterial species were isolated, being the P. agglomerans the most frequent species (100%). Twenty-two of the 27 isolates (81.4%) exhibited antibiotic resistance, varying from one to eight of the 12 antimicrobials commonly used. Resistance to amoxicillin was the most prevalent (70.4%), followed by azithromycin (22.2%) and ceftriaxone (18.5%). None of the strains were resistant to gentamicin, tobramycin, ciprofloxacin or tetracycline. The H. alvei was the main species presenting multidrug resistance, including resistance against meropenem, which is an important finding. These results could provide interesting information on the health of these endangered wild grey-breasted parakeets. They could also indicate that the obtained isolates are part of a group of bacteria that are typical components of the enteric microbiota of birds, which present elevated rates of resistance to amoxicillin.(AU)


O periquito-de-cara-suja (Pyrrhura griseipectus) é uma espécie de psitacídeo considerado pela IUCN como ameaçado de extinção, resultado do comércio ilegal e do desmatamento. Atualmente, essa espécie endêmica é encontrada apenas em três áreas no estado do Ceará, Brasil. O objetivo deste estudo foi investigar a frequência e a diversidade de Enterobacteriaceae em periquitos de peito cinza adultos selvagens e determinar sua suscetibilidade a agentes antimicrobianos. Amostras de suabes cloacais foram coletadas de 27 indivíduos e de suabes ambientais (suabes de arrasto) de cinco ninhos utilizados por essas aves. Vinte e sete cepas de nove espécies de Enterobacteriaceae foram isoladas a partir de suabes cloacais, sendo as cepas bacterianas mais prevalentes Hafnia alvei (22%) e Pantoea agglomerans (22%). Das amostras ambientais de ninhos foram isoladas sete linhagens de três espécies bacterianas, sendo P. agglomerans a espécie mais frequente (100%). Vinte e dois dos 27 isolados (81,4%) exibiram resistência a antibióticos, variando de um a oito dos 12 antimicrobianos comumente usados. A resistência a amoxicilina foi a mais prevalente (70,4%), seguida por azitromicina (22,2%) e ceftriaxona (18,5%). Nenhuma das cepas era resistente à gentamicina, tobramicina, ciprofloxacina ou tetraciclina. H. alvei foi a principal espécie que apresentou resistência a múltiplas drogas e que também esteve associada a um outro achado relevante desta pesquisa, que foi a detecção de um caso de resistência ao meropenem. Esses dados fornecem informações relevantes sobre a saúde desses periquitos selvagens ameaçados e permite concluir que os isolados obtidos fazem parte de um grupo de bactérias que normalmente compõe a microbiota entérica das aves, sendo a amoxicilina envolvida em elevadas taxas de resistência.(AU)


Subject(s)
Animals , Parakeets/microbiology , Parrots/microbiology , Enterobacteriaceae/isolation & purification , Animals, Wild , Enterobacteriaceae Infections , Anti-Infective Agents/analysis
2.
Pesqui. vet. bras ; 41: e06818, 2021. tab, graf
Article in English | ID: biblio-1340351

ABSTRACT

Salmonella is a major cause of foodborne illness worldwide, and poultry and its derived products are the most common food products associated with salmonellosis outbreaks. Some countries, including Brazil, have experienced an increased prevalence of Salmonella Heidelberg among their poultry flocks. Some isolates have also presented high resistance to antimicrobial agents and persist in the poultry farm environment. This study aimed to compare the susceptibility of S. Heidelberg strains isolated in 2006 with those isolated in 2016 against disinfectants and antimicrobial agents. The results showed that all the strains were highly susceptible to sodium hypochlorite, regardless of the conditions and year of isolation. Resistance to benzalkonium chloride varied according to the conditions applied, but not to the year of isolation. Increased antimicrobial resistance from 2006-2016 was observed only for tetracycline. The results suggest that the antimicrobial and disinfectant resistance of S. Heidelberg did not increase for ten years (2006-2016). However, further analysis should include a larger number of S. Heidelberg isolates from poultry origin and additional antimicrobial agents for more precise conclusions about the increasing in antimicrobial resistance in the last years.(AU)


Salmonella é uma das principais causas das doenças transmitidas por alimento em todo o mundo, e a carne de frango e produtos derivados são os principais alimentos associados com surtos de salmonelose em humanos. Alguns países, incluindo o Brasil, têm observado um aumento da ocorrência de Salmonella Heidelberg nas suas granjas avícolas. Além disto, alguns isolados têm apresentado alta resistência aos antimicrobianos e têm persistido no ambiente de produção avícola. Neste contexto, o objetivo deste estudo foi comparar a susceptibilidade de cepas de S. Heidelberg isoladas em 2006 com aquelas isoladas em 2016 contra desinfetantes e agentes antimicrobianos. Os resultados demonstraram que as cepas foram altamente resistentes a hipoclorito de sódio, independentemente das condições e do ano de isolamento. A resistência ao cloreto de benzalcônio variou de acordo com as condições testadas, mas não com o ano de isolamento. Um aumento da resistência aos antimicrobianos de 2006 a 2016 foi observado apenas para tetraciclina. Os resultados sugerem que a resistência aos desinfetantes e aos antimicrobianos não aumentou em um período de dez anos (2006-2016). Entretanto, novas análises devem incluir um número maior de cepas de S. Heidelberg isoladas de fontes avícolas e outros agentes antimicrobianos para uma conclusão mais precisa sobre o aumento da resistência antimicrobiana nos últimos anos.(AU)


Subject(s)
Animals , Poultry/microbiology , Salmonella Infections, Animal/microbiology , Disinfectants/analysis , Anti-Infective Agents/analysis
3.
Braz. arch. biol. technol ; 64: e21190749, 2021. tab, graf
Article in English | LILACS | ID: biblio-1278444

ABSTRACT

Abstract Bacteriocin has been identified as an excellent alternative to chemical preservatives due to its astonishing antimicrobial activity against food spoiling and food-borne pathogens. So there is a need to identify the newer and potent sources of bacteriocin producers. This study aims the isolation of potent bacteriocin producing microorganism from fresh fruits and vegetables, its production, purification, and characterization. Firstly, 43 isolates were analysed for its antimicrobial potential, out of which7 were found to inhibit the growth of various pathogens. Considering the results of antimicrobial activity; the microorganism isolated from mango was regarded as the most potent one; which was identified as Bacillus subtilis VS.70% ammonium sulphate precipitated and dialysed bacteriocin was purified using DEAE cellulose and sephadex G75 chromatography. Bacteriocin was purified by 24.64 fold with 8.65% recovery and its molecular weight was found to be 31.2kDa. The Purified bacteriocin was found to be stable at broad pH and temperature. It was found to be degraded by various proteases studied confirming its proteinaceous nature. Considering all these attributes; the purified bacteriocin isolated from Bacillus subtilis VS can be exploited by various food industries.


Subject(s)
Peptide Hydrolases/analysis , Bacteriocins/analysis , Anti-Infective Agents/analysis , Bacillus subtilis , Chromatography
4.
Arq. odontol ; 56: 1-10, jan.-dez. 2020. ilus, tab
Article in Portuguese | LILACS, BBO | ID: biblio-1145405

ABSTRACT

Objetivo: Avaliar e comparar os efeitos antimicrobiano e antibiofilme, e a citotoxicidade promovida pela associação do hidróxido de cálcio ao óleo essencial de Melaleuca alternifolia (MA), em diferentes concentrações, e ao propilenoglicol (PG). Métodos: As seguintes medicações compuseram os grupos experimentais: G1) HC/MA 1%; G2) HC/MA 5%; G3) HC/MA 10%; G4) HC/MA 20%; e G5) HC/PG. Solução salina 0,85% e meio DMEM serviram como controle nos testes antimicrobianos e de citotoxidade em fibroblastos do ligamento periodontal humano (FbLP), respectivamente. A atividade antimicrobiana (n = 12) foi avaliada por meio do teste de difusão em ágar. O efeito antibiofilme (n = 12) imediato das medicações foi avaliado por meio do teste de viabilidade bacteriana em biofilmes de 72 horas de E. faecalis, formados sobre discos de dentina e tratados por sete dias com as medicações. Após a coleta microbiológica do biofilme remanescente, os discos de dentina foram imersos em meio estéril e armazenados por mais sete dias, para a análise do efeito antibiofilme residual das medicações, quando nova coleta microbiológica foi realizada. A atividade metabólica de FbLP foi avaliada por meio do ensaio colorimétrico MTS (n = 9). Os valores médios dos halos de inibição, em mm, das unidades formadoras de colônia, e o percentual de atividade metabólica celular foram analisados pelos testes Kruskal-Wallis e post hoc Dunn (α = 5%). Resultados:Todas as medicações experimentais apresentaram superior ação antimicrobiana e antibiofilme comparadas ao controle, solução salina (p < 0,05), e mantiveram viáveis os FbLP, semelhante ao controle DMEM (p > 0,05). Conclusão: A associação do óleo essencial de Melaleuca alternifolia, nas concentrações de 1%, 5%, 10% e 20%, ao hidróxido de cálcio promoveu excelente ação antimicrobiana, antibiofilme e biocompatibilidade com fibroblastos, de forma semelhante à associação com propilenoglicol.


Aim:To evaluate and compare the antimicrobial and antibiofilm effect, as well as the cytotoxicity of calcium hydroxide (CH) associated with the Melaleuca alternifolia (MA)essential oil, in different concentrations, and with propylene glycol. Methods: The following medications composed the experimental groups: G1) CH/MA 1%; G2) CH/MA 5%; G3) CH/MA 10%; G4) CH/MA 20%; and G5) CH/PG. Saline solution and culture medium DMEM were used as a control in antimicrobial and cytotoxicity tests in human periodontal ligament fibroblasts (PDLF), respectively. The antimicrobial activity (n = 12) was evaluated by the disk-diffusion agar method. The immediate antibiofilm effect (n = 12) of the medications was evaluated for bacterial viability in 72 hours-biofilms of E. faecalis, formed on the dentin disc surface and treated for seven days with medications. After microbiological sampling of the remaining biofilm, the dentin discs were immersed in sterile culture medium and stored for another seven days, for analysis of the residual antibiofilm effect of the medications, when a new microbiological sampling was performed. PDLF viability was evaluated by MTS colorimetric assay (n = 9). The mean values of the inhibition halos, in mm, the colony forming units, and the metabolic cell activity percentage were analyzed by means of Kruskal-Wallis and post hoc Dunn (α = 5%) tests. Results:All of the experimental medications presented higher antimicrobial and antibiofilm effects, when compared to the saline solution control (p < 0.05), and maintained the PDLF feasible, similar to the DMEM control (p > 0.05). Conclusions:The association of the Melaleuca alternifolia essential oil, at concentrations of 1%, 5%, 10%, and 20%, with calcium hydroxide promoted an excellent antimicrobial and antibiofilm activity, and biocompatibility with fibroblasts, similarly to the association with propylene glycol.


Subject(s)
Calcium Hydroxide/analysis , Oils, Volatile/therapeutic use , Endodontics , Anti-Infective Agents/analysis , Antibiotics, Antineoplastic , Enterococcus faecalis , Fibroblasts , Regenerative Endodontics
5.
Arq. bras. med. vet. zootec. (Online) ; 71(4): 1251-1259, jul.-ago. 2019. tab, graf
Article in Portuguese | ID: biblio-1038617

ABSTRACT

O objetivo deste estudo foi avaliar a atividade antimicrobiana in vitro do óleo essencial de Tagetes minuta L. contra Staphylococcus aureus e Escherichia coli e a citotoxicidade sobre células epiteliais da glândula mamária bovina (MAC-T), visando a seu uso no tratamento da mastite bovina. A análise qualitativa do óleo revelou cis-tagetona (24,24%), di-hidrotagetona (16,65%), 1,3,6-octatrieno-3,7-dimetil-E (13,61%), trans-ocimenona (13,52%) e cis-ocimenona (10,06%) como compostos majoritários. Nos ensaios da atividade antimicrobiana, a concentração inibitória mínima (CIM) verificada foi de 1 mg/mL para a cepa padrão (ATCC 25923), cinco isolados de S. aureus provenientes de leite de vacas com mastite e a cepa padrão resistente à meticilina (MRSA) (ATCC 33592). Para a cepa padrão de E. coli (ATCC 8739) e dois isolados de leite de vacas com mastite, a CIM foi de 3 mg/mL. Elevado efeito citóxico do óleo sobre as células da linhagem MAC-T foi constatado. Concentrações superiores a 10 (g/mL do óleo resultaram em mais de 90% de morte celular. Tais resultados sugerem que, apesar da atividade antimicrobiana contra agentes causadores da mastite bovina, a utilização intramamária do óleo de T. minuta não seria recomendada. É importante destacar a sensibilidade da cepa MRSA ao óleo essencial, o que evidencia seu potencial como antisséptico e sanitizante.(AU)


The aim of this study was to evaluate the in vitro antimicrobial activity of Tagetes minuta L. essential oil against Staphylococcus aureus and Escherichia coli, and its cytotoxicity to bovine mammary epithelial cells (MAC-T line), aiming at its use for bovine mastitis treatment. The qualitative analysis of the oil by GC-MS identified cis-tagetone (24.24%), dihydrotagetone (16.65%), 1,3,6-Octatriene 3,7-Dimethyl-E (13.61%); trans-ocimenone (13.52%) and cis-ocimenone (10.06%) as major compounds. Antimicrobial activity was determined by broth microdilution technique and revealed the minimum inhibitory concentration of 1mg/mL for the standard strain of S. aureus (ATCC 25923) and five bacterias isolated from mastitic milk, including a multiresistant strain (ATCC 33592); and 3mg/ml for the standard strain of E. coli (ATCC 8739) and two bacterias isolated from mastitic milk. However, a strong citotoxic effect on MAC-T cells was found. Oil concentrations from 10(g/mL resulted in over 90% of cell death. The results suggest that although the antimicrobial activity was identified against the main agents of bovine mastitis, the intramammary use of T. minuta oil may not be recommended. On the other hand, it is important to highlight the sensibility of the MSRA strain to the essential oil, which evidences its potential as an antiseptic or sanitizer.(AU)


Subject(s)
Animals , Female , Cattle , Oils, Volatile/therapeutic use , Tagetes , Mastitis, Bovine/prevention & control , Anti-Infective Agents/analysis , Plants, Medicinal
6.
Pesqui. vet. bras ; 39(5): 308-316, May 2019. tab
Article in English | ID: biblio-1012746

ABSTRACT

Bovine mastitis is the most frequent disease worldwide in dairy herds, causing high economic losses to producers and industry, as well as having implications for public health due to the zoonotic potential of some agents involved in its etiology and the increased risk of antimicrobial residues in milk and its derivatives. Considering the multifactorial aspect of this disease, knowledge of the agents involved in its etiology and their antimicrobial susceptibility profiles is very important. This study was conducted with 306 dairy herds from the Campo das Vertentes region, located in the south of Minas Gerais state, whose owners were milk suppliers to a dairy in the same region. The study involved approximately 34,000 dairy cows and covered an area of approximately 12,564 km2. In these herds, prevalence rates of Staphylococcus aureus and Streptococcus agalactiae and their relationship with bulk milk somatic cell counts (BMSCC), total bacterial counts (TBC), and daily production were evaluated. In addition, analyses of resistance of these pathogens to the antimicrobials most commonly used in the treatment of mastitis in dairy herds were performed. Microbiological analyses of milk samples from collect from bulk milk tanks were performed aiming to evaluate the prevalence of S. aureus and S. agalactiae. For these proposes, the modified Baird-Parker Agar medium was used for detection of S. aureus and the modified Edwards Agar medium, enriched with 5% defibrinated sheep blood, was used for detection of S. agalactiae. The disc diffusion technique was applied to evaluate antimicrobial resistance. Results show high prevalence rates of S. aureus (70.3%) and S. agalactiae (67.0%) in the dairy farms studied, with 47.71% of the herds showing both pathogens. Associations between BMSCC and the presence of pathogens S. aureus and S. agalactiae and between TBC and the presence of S. agalactiae were observed, demonstrating the influence of these pathogens in milk quality. No variation was observed in the distribution of S. aureus and S. agalactiae in the different strata of daily production. High levels of resistance and multi-resistance were observed among the pathogens S. aureus and S. agalactiae. The results indicate the need for more effective control measures for mastitis caused by S. aureus and S. agalactiae in the dairy herds of the region studied and more judicious use of antimicrobials in order to reduce the problem of resistance to them.(AU)


A mastite bovina é a doença de maior frequência em rebanhos leiteiros em nível mundial, acarretando grandes prejuízos econômicos aos produtores e à indústria. Além disso, esta enfermidade tem implicações na saúde pública, devido ao potencial zoonótico de alguns agentes envolvidos em sua etiologia e por aumentar os riscos de resíduos de antimicrobianos no leite e derivados. Considerando o aspecto multifatorial da mastite bovina, o conhecimento dos agentes envolvidos em sua etiologia e os perfis de suscetibilidade aos antibióticos é de suma importância. O estudo envolveu 306 fazendas de leite da região de Campo das Vertentes, localizada no sul de Minas Gerais, cujos proprietários eram fornecedores de leite para um laticínio da região, totalizando aproximadamente 34.000 animais e abrangendo uma área aproximada 12.564 km2. Nestes rebanhos, avaliaram-se a prevalência de Staphylococcus aureus e Streptococcus agalactiae e a relação destes agentes com os índices de contagem de células somáticas do leite do tanque de expansão (CCSt), contagem bacteriana total (CBT) e produção diária. Analisou-se também a resistência destes patógenos aos antimicrobianos mais comumente utilizados no tratamento da mastite em rebanhos leiteiros. Análises microbiológicas de amostras de leite dos tanques de expansão foram realizadas para se determinar as prevalências dos patógenos S. aureus e S. agalactiae. Para a detecção de S. aureus, utilizou-se o meio seletivo Ágar Baird-Parker modificado e para a detecção de S. agalactiae, o meio seletivo Ágar Edwards modificado, enriquecido com 5% de sangue ovino desfibrinado. Foi utilizada a técnica de difusão em discos para a avaliação de resistência aos antimicrobianos. Os resultados apontaram altas prevalências de S. aureus (70,3%) e de S. agalactiae (67,0%), com 47,71% dos rebanhos examinados apresentando ambos os agentes. Verificaram-se associações entre a CCSt e a presença dos patógenos S. aureus e S. agalactiae, e também entre a CBT e a presença de S. agalactiae, demonstrando a interferência negativa destes patógenos nestes quesitos de qualidade. Não se observaram variações nas distribuições dos patógenos S. aureus e nem S. agalactiae em função da produção diária das propriedades estudadas. Níveis elevados de resistência e de multirresistência foram observados para ambos os agentes. Os resultados apontam a necessidade de medidas mais efetivas de controle para S. aureus e S. agalactiae nos rebanhos da região estudada e do uso mais criterioso dos antimicrobianos, visando minimizar o problema da resistência aos mesmos.(AU)


Subject(s)
Animals , Female , Cattle , Staphylococcus aureus , Streptococcus agalactiae , Milk/microbiology , Anti-Infective Agents/analysis
7.
Braz. J. Pharm. Sci. (Online) ; 55: e17200, 2019. tab, graf
Article in English | LILACS | ID: biblio-1039047

ABSTRACT

Natural products are rapidly becoming the primary sources of novel antimicrobial agents, as resistance to existing antimicrobial agents is increasing. Apart from determining the antimicrobial activity of natural products, it is also important to understand their effects on the virulence factors of microorganisms. This study aimed to determine the antimicrobial activity of Sternbergia species prevalent in Turkey and investigate their role in the inhibition of germination tube and biofilm formation, both of which are known to be important virulence factors of Candida albicans. The antimicrobial activities of the plant extracts were evaluated using bore-plate and broth microdilution method. The extracts' capacity to inhibit the formation of the germ-tube was also evaluated. The findings of our study revealed that Sternbergia lutea, Sternbergia vernalis possessed antimicrobial activities, with MIC values ranging between 0.048 mg/mL and 0.39 mg/mL. The highest antimicrobial activity was observed against Candida dubliniensis (0.048 mg/mL). While evaluating the inhibition of fungal germination activities, S. vernalis extract (at a concentration of 0.09 mg/mL) was found to be the most effective against C. albicans ATCC 90028 strain. The results also indicated that S. vernalis extracts at sub-MIC levels inhibited germ tube formation and modulated the tail-length of germinated cells, both of which are important virulence factors of C. albicans. Furthermore, the inhibition of biofilm-formation was also investigated, and it was found that two Sternbergia spp. extracts at or below MIC levels inhibited biofilm formation.


Subject(s)
Biofilms/drug effects , Amaryllidaceae/classification , Anti-Infective Agents/analysis , Candida albicans , Plant Extracts/adverse effects , Virulence Factors
8.
São Paulo; s.n; s.n; 2019. 126 p. ilus, graf, tab.
Thesis in Portuguese | LILACS | ID: biblio-1007440

ABSTRACT

O desenvolvimento de resistência antimicrobiana e a consequente seleção de microrganismos multirresistentes consolidam-se como grandes ameaças à saúde global. Neste contexto, a busca por novas drogas antimicrobianas/microbicidas é fundamental e compostos como os peptídeos antimicrobianos (AMPs) tornaram-se alvos atraentes. Os AMPs são compostos químicos de massa molar média e grande diversidade estrutural, produzidos por todos os seres vivos e com capacidade de inibir o crescimento de e/ou matar microrganismos. O AMP Cheferina I (Chef I) foi isolado das raízes de Capsella bursa-pastoris e é resultado da proteólise de uma proteína da família das proteínas ricas em glicina, que em plantas estão relacionadas às funções de defesa e cicatrização. O nosso grupo de pesquisa foi pioneiro no desenvolvimento e estudo de análogos truncados amidados deste AMP atípico rico em glicina (67,9%) e histidina (28,6%), que se mostraram ativos frente às diferentes cepas de Candida e a S. cerevisiae pela internalização/ação celular acompanhada de manutenção da integridade da membrana plasmática; o análogo amidado (Chef Ia) e o análogo marcado com 5(6)-carboxifluoresceína/FAM (FAM-Chef Ia) tiveram as suas atividades antifúngicas potencializadas por íons Zn2+. Este trabalho deu continuidade ao estudo do efeito dos íons metálicos divalentes Zn2+, Cu2+, Ca2+ e Mg2+ nas atividades anticandida/fungistática e candidacida/fungicida a diferentes pHs e forças iônicas, estruturas e localizações intracelulares destes análogos. Os resultados na ausência de íons em pH 5,1 revelaram maior atividade do análogo fluorescente em relação à do não fluorescente. Neste mesmo pH, as atividades anticandida e candidacida de Chef Ia foram influenciadas negativamente pelos íons Ca2+ e Mg2+ (2-4 vezes) enquanto que, na presença de íons Zn2+ as atividades anticandida de ambos os análogos foram aumentadas (Chef Ia: 8-64 vezes; FAM-Chef Ia: 4-32 vezes). Os íons Cu2+ aumentaram a atividade anticandida de Chef Ia (2-4 vezes), mas não a do análogo fluorescente, mas as atividades candidacidas de ambos foram melhoradas (Chef Ia: 2-8 vezes; FAM-Chef Ia: 2 vezes). Em pH 5,1, os íons Zn2+ mantiveram a atividade anticandida de Chef Ia em alta força iônica, mas só FAM-Chef Ia exibiu atividade candidacida. Em pH 7,4 ambos análogos foram inativos em baixa e alta forças iônicas na ausência e presença de Zn2+ ou Cu2+. As maiores porcentagens de folhas-ß-antiparalelas e dobras foram observadas no espectro de DC de Chef Ia em pH 7,4, sendo que aqueles registrados em pH 5,1 e 7,4 em presença de íons Zn2 e Cu2+ indicaram a formação de quelatos estruturalmente distintos. Ambos os peptídeos são bioquelantes em potencial, sendo as proporções peptídeo: íon obtidas as seguintes: FAM-Chef Ia = 1:2 para Cu2+, 1:10 para Zn2+; Chef Ia = 1:1 para Cu2+. A análise da internalização celular de FAM-Chef Ia permitiu a suposição de dois mecanismos de internalização (translocação direta e endocitose), sendo que nas células vivas a presença de Zn2+ afetou negativamente a translocação direta (p 0,0343) e potencializou a endocitose (p 0,0002)


The development of antimicrobial resistance and the consequent selection of multiresistant microorganisms have become major threats to global health. In this context, the search for new antimicrobial/microbicidal drugs is crucial and the antimicrobial peptides (AMPs) have been seen as attractive targets. AMPs are chemical compounds of medium molecular mass and high structural diversity produced by all living beings, capable of inhibiting the growth of microorganisms and killing them. The AMP Shepherin I (Shep I) was isolated from the roots of Capsella bursa-pastoris, being a bioactive peptide encrypted in a glycine-rich protein from a family that in plants are strictly related to defense and healing functions. Our research group has pioneered the development and study of amidated truncated analogues of this atypical glycine- (67.9%) and histidine-rich (28.6%) AMP, which has shown activity against different strains of Candida and S. cerevisiae through cellular internalization with maintenance of the plasma membrane integrity. The amide analogue (Chef Ia) and its fluorescent analog labeled with 5 (6) - carboxyfluorescein / FAM (FAM-Chef Ia) had their antifungal activities potentiated by Zn2+ ions, so the present work continued examining the effect of the divalent metallic ions Zn2+, Cu2+, Ca2+ and Mg2+ on the anticandidal/fungistatic and candidacidal/fungicide activities at different pHs and ionic forces, structures and intracellular locations of these analogues. The results in the absence of those ions at pH 5.1 revealed that the fluorescently labelled analog was more potent than the nonfluorescent. At the same pH, Shep Ia anticandidal and candidacidal activities were negatively influenced by Ca2+ and Mg2+ ions (2-4 fold), whereas in the presence of Zn2+ ions the anticandidal activities of both analogues were increased (Shep Ia: 8-64 fold, FAM- Shep Ia: 4-32 fold). Cu2+ ions increased Shep Ia anticandidal activity (2-4 fold) but not that of FAM-Shep Ia, nevertheless, the candidacidal activities of both analogues were increased (Shep Ia: 2-8 fold, FAM-Shep Ia: 2 fold). Also at pH 5.1, the Zn2+ ions helped retaining the anticandidal activity of Shep Ia at high ionic strength, although only FAM-Shep Ia exhibited candidacidal activity. At pH 7.4 both analogues were inactive at low and high ionic strengths in the absence or presence of Zn2+ or Cu2+. The highest percentages of antiparallel ß-sheet and turns were observed in Shep Ia CD spectrum at pH 7.4, while those recorded at pH 5.1 and 7.4 in the presence of Zn2+ or Cu2+ ions indicated the formation of structurally different chelates. Both peptides are potential biochelates, with the following peptide:ion ratios: FAM-Shep Ia = 1: 2 for Cu2+, 1:10 for Zn2+; Shep Ia = 1: 1 for Cu2+. The analysis of the cellular internalization of FAM-Chef Ia allowed the assumption of two mechanisms of internalization (direct translocation and endocytosis) and in the living cells the presence of Zn2+ negatively affected the direct translocation (p 0.0343) and potentiated endocytosis (p 0.0002)


Subject(s)
Cell-Penetrating Peptides/adverse effects , Anti-Infective Agents/analysis , Plant Roots/adverse effects , Capsella/anatomy & histology
9.
Pesqui. vet. bras ; 38(2): 244-249, fev. 2018. tab, graf, ilus
Article in Portuguese | ID: biblio-895570

ABSTRACT

O uso indiscriminado de antimicrobianos tem proporcionado a algumas bactérias patogênicas a seleção de cepas multirresistentes, situação que pode ser agravada pela formação do biofilme. Desta forma, as nanopartículas de prata (AgNPs) vêm se destacando como uma alternativa inovadora, de baixo custo e eficiente contra doenças causadas por bactérias. O objetivo deste estudo foi determinar a atividade antimicrobiana das AgNPs e a interferência na formação do biofilme de Aeromonas spp. obtidas de organismos aquáticos. As AgNPs foram sintetizadas quimicamente utilizando como agente redutor o citrato trissódico e caracterizadas por espectrofotometria ultravioleta-visível (UV-Vis). A atividade antimicrobiana foi realizada contra três isolados pelo método de microdiluição em caldo para determinar a concentração bactericida mínima (CBM) e um cultivo com CCCP, um inibidor da bomba de efluxo, foi realizado para complementar o efeito das AgNPs. A interferência no biofilme foi realizada segundo o protocolo de formação e consolidado, além da caracterização desta estrutura de resistência por microscopia eletrônica de varredura. No teste da CBM, as AgNPs não foram capazes de inativar o crescimento dos isolados, ao passo que o nitrato de prata obteve eficiência em diferentes concentrações. Na presença do inibidor de bomba de efluxo, dos isolados analisados, um passou de resistente a sensível na presença das nanopartículas. As AgNPs foram eficazes em diminuir a formação de biofilme, como também atuaram sobre o biofilme consolidado em todos os isolados testados. Estes resultados indicam o potencial das nanopartículas de prata em interferir com o biofilme de Aeromonas spp. de organismos aquáticos e seres humanos.(AU)


The indiscriminate use of antibiotics has selected some pathogenic bacteria being multidrug-resistant, a situation that can be exacerbated by biofilms formation. Thus, silver nanoparticles (AgNPs) have been highlighted as an innovative alternative, low-cost and effective against bacterial diseases. The aim of this study was to determine the antimicrobial activity of AgNPs and the interference in Aeromonas spp. biofilm formation. The strains were obtained from aquatic organisms. The AgNPs were chemically synthesized using as reducing agent trisodium citrate and characterized by ultraviolet-visible spectroscopy (UV-Vis). The antimicrobial activity was carried out against three isolates by the microdilution broth method for determining minimum bactericidal concentration (CBM) and cultivation of CCCP, an inhibitor of the efflux pump, was carried out to complement the effect of AgNPs. Interference in the biofilm formation was performed according to the protocol and consolidated, within the resistance structure characterization by scanning electron microscopy. In the test of the CBM, the AgNPs were unable to inactivate the growth of the isolates, while the silver nitrate obtained efficiency in different concentrations. In the efflux pump inhibitor presence the isolates were analyzed, one went from resistant to nanoparticles to sensitive. The AgNPs were effective in reducing of biofilm formation and acted on the consolidated biofilm in all tested isolates. These results indicate the silver nanoparticles to interfere with Aeromonas spp. biofilm from aquatic organisms and human bodies.(AU)


Subject(s)
Animals , Aeromonas , Anti-Infective Agents/analysis , Aquatic Organisms/microbiology , Biofilms , Metal Nanoparticles/analysis , Silver , Drug Resistance, Bacterial , Microbial Sensitivity Tests/veterinary
10.
Pesqui. bras. odontopediatria clín. integr ; 18(1): 4150, 15/01/2018. tab
Article in English | LILACS, BBO | ID: biblio-966923

ABSTRACT

Objective: To determine the antimicrobial efficacy of silver, titanium dioxide and zinc oxide nanoparticles against Streptococcus mutans. Material and Methods: Serial dilution method was employed for preparing 1%, 0.5%, 0.25% concentrations of the three test compounds. ATCC 25175 strain of streptococcus mutans was used to assess the antimicrobial activity of test compounds. Equal quantity of BHI broth was dispensed in test tubes containing sectioned tooth and to this the prepared bacterial inoculum was added. Prepared concentrations of test compounds were added accordingly and incubated for 24hrs at 370C. Then, the sectioned tooth was removed and the adherent bacteria were transferred into saline solution by vortexing. These suspensions were transferred onto sterile blood agar plate to make lawn culture and were further incubated at 370C for 24hrs to determine viable bacterial count. The number of colonies were counted manually from each plate and recorded for further analysis. Decrease in number of colonies represents the effective concentration of the test compound against the inhibition of biofilm formation. Results: A significant difference in the colony forming units among all three concentrations of silver (Ag), titanium dioxide (TiO2) and zinc (ZnO) nanoparticles was noted and the antimicrobial effect of nanoparticles was concentration dependent. Inter group comparison of colony forming units with 1%, 0.5% and 0.25% of the test compound revealed that the colony forming units on the ZnO nanoparticles demonstrated highest value followed by TiO2 and the least were with that of the Ag nano particles. Conclusion: Silver, Zinc oxide and Titanium dioxide showed significant antimicrobial effects and the antimicrobial effect of nanoparticles was concentration dependent.


Subject(s)
Silver , Streptococcus mutans , Nanoparticles , Anti-Infective Agents/analysis , Zinc Oxide , Data Interpretation, Statistical , Evaluation Study
11.
Pesqui. vet. bras ; 38(3): 462-469, mar. 2018. tab, graf
Article in Portuguese | ID: biblio-964900

ABSTRACT

Este estudo objetivou avaliar a ação antimicrobiana e antisséptica do extrato etanólico bruto da folha da Hymenaea martiana (Jatobá). O estudo foi realizado no Laboratório de Microbiologia e Imunologia da UNIVASF, na cidade de Petrolina-PE. Os extratos foram preparados utilizando diferentes diluentes, sendo estes: álcool etílico absoluto e a água destilada. Em seguida, foi empregada a técnica da Concentração Inibitória Mínima (MIC) e da Concentração Bactericida Mínima (CBM). Todos os ensaios foram realizados em triplicata. A CBM média do extrato diluído em etanol foi de 358µg/µL e do extrato diluído em água destilada foi igual a 520,82µg/mL. Não houve diferença (P<0,05) quanto à inibição bacteriana para o extrato diluído em álcool etílico absoluto ou água destilada autoclavada. Ao comparar a atividade do extrato diluído em álcool etílico absoluto e a relação com a presença do gene blaZ, observou-se que os isolados negativos para o gene pesquisado apresentaram uma CBM igual a 412,3µg/mL, e, quando comparadas aos que foram positivos para o gene blaZ, que foi de 308,80µg/mL, contudo sem diferença estatística. Quanto à inibição das bactérias utilizando extrato aquoso, a atividade foi igual para as bactérias com ou sem o gene (520,82µg/mL). Desse modo, tanto o extrato diluído em álcool etílico absoluto quanto em agua destilada autoclavada demonstrou atividade antimicrobiana, sugerindo que ocorreu extração de substâncias bioativas. Em relação ao potencial antisséptico, H. martiana teve ação pareada com o cloro, contudo aquele agiu mais rapidamente, enquanto o cloro agiu de modo ideal uma hora após a aplicação; ambos os resultados destacam que o extrato etanólico bruto das folhas de H. martiana possui potencial de combate à proliferação de bactérias ambientais e infecciosas, surgindo como uma forma de prevenir a mastite.(AU)


This study aimed to evaluate the antimicrobial and antiseptic action of the crude ethanolic extract of Hymenaea martiana leaves. The study was conducted at the Laboratory of Microbiology and Immunology of UNIVASF, city of Petrolina, state o Pernambuco. The extracts were prepared using different solvents, such as absolute ethyl alcohol and distilled water. Then, Minimum Inhibitory Concentration (MIC) and Minimum Bactericidal Concentration (MBC) techniques were used. All assays were performed in triplicate. The average of MBC extract diluted in ethanol was 358µg/mL, and the extract diluted in distilled water was equal to 520.82µg/mL. There was no difference (P<0.05) and bacterial inhibition to extract diluted in absolute ethanol or autoclaved distilled water. Comparing the activity of the extract diluted in ethanol and the relation with the presence of blaZ gene, it was observed that the negative strains for there searched gene showed a MBC equal to 412.3µg/mL in relation to those that were positive for blaZ gene, that was 308.80µg/µL, and, however, there was no statistical difference. The bacterial inhibition activity using an aqueous extract was equal for the bacteria that had or not the blaZ gene (520.82µg/mL). Thus, the extract diluted in absolute ethanol in autoclaved distilled water as demonstrated antimicrobial activity, suggesting that occurred extraction of bioactive substances. Regarding the antiseptic potential, H. martiana had the same action of chlorine, although, this acted immediately, while the chlorine action happened properly an hour after the application. Both results pointed out that the crude ethanolic extract of H. martiana leaves has potential to combat the proliferation of environmental and infectious bacteria, emerging as a way to prevent mastitis.(AU)


Subject(s)
Animals , Staphylococcus/pathogenicity , Goats/microbiology , Anti-Infective Agents/analysis , Hymenaea/chemistry , Mammary Glands, Animal
12.
São Paulo; s.n; s.n; 2018. 76 p. tab.
Thesis in Portuguese | LILACS | ID: biblio-997669

ABSTRACT

Listeria monocytogenes é o microrganismo patogênico de maior relevância em carnes processadas prontas para consumo. A presença frequente de L. monocytogenes no ambiente pode levar a uma contaminação dos produtos após o processamento industrial e como esses produtos não passam por tratamento bactericida antes de serem consumidos, a saúde do consumidor pode estar em risco. Para inibir a multiplicação de L. monocytogenes nos produtos cárneos durante o armazenamento em refrigeração após o processamento, os fabricantes podem utilizar diversos aditivos antimicrobianos na formulação destes produtos. Este estudo objetivou avaliar a atividade antimicrobiana de aditivos tradicionalmente empregados em produtos cárneos processados, e de quatro novos blends preparados à base de nisina (Nisaplin®) contra cepas de L. monocytogenes, fazendo-se a avaliação in vitro e in situ, em mortadelas experimentalmente contaminadas, formuladas com os compostos estudados, armazenadas à vácuo e em refrigeração (8 °C) por 70 dias. Os compostos extrato de alecrim, diacetato de sódio e Nisaplin®, quando testados in vitro, apresentaram maior eficiência na inibição das cepas de L. monocytogenes que lactato de sódio e vinagre tamponado. Quando testados in vitro, os produtos comerciais BioVia® CL600 e NovaGARD® LM100 e os quatro blends utilizados no preparo das mortadelas foram igualmente efetivos na inibição de L. monocytogenes. De acordo com os resultados dos testes in situ, o melhor controle de L. monocytogenes em mortadelas durante 70 dias a 8 °C ocorreu nos produtos preparados com o blend contendo extrato de alecrim, diacetato de sódio, vinagre tamponado e Nisaplin®. O blend contendo extrato de alecrim, lactato de sódio e Nisaplin®, foi o menos efetivo entre os blends testados


Listeria monocytogenes is the most important microbial pathogen in ready-to-eat processed meat products. The frequent presence of L. monocytogenes in the environment can lead to product contamination after industrial processing and since these products do not have a bactericidal step before consumed, consumer health may be at risk. To inhibit the multiplication of L. monocytogenes in processed meat products during refrigerated storage, manufacturers may use various antimicrobial additives in the formulation of these products. This study aimed to evaluate the in vitro and in situ activity of additives traditionally used in processed meat products and four new blends based on nisin (Nisaplin®) against L. monocytogenes, in experimentally contaminated bolognas, formulated with the studied compounds and stored under vacuum and refrigerated (8 °C) for 70 days. Rosemary extract, sodium diacetate and Nisaplin®, when tested in vitro, were more effective than sodium lactate and buffered vinegar for the inhibition of the L. monocytogenesstrains. When tested in vitro, the commercial products BioVia® CL600 and NovaGARD® LM100 and the four blends used in bologna preparation were equally effective in inhibiting L. monocytogenes. According to the results of the in situ tests, the best control of L. monocytogenes in bolognas for 70 days at 8 °C occurred in the products prepared with the blend containing rosemary extract, sodium diacetate, buffered vinegar and Nisaplin®. The blend containing rosemary extract, sodium lactate and Nisaplin®, was the least effective among the tested blends


Subject(s)
Food Additives/analysis , Listeria monocytogenes/isolation & purification , Anti-Infective Agents/analysis , Foods of Animal Origin
13.
São Paulo; s.n; s.n; 2018. 114 p. graf, tab, ilus.
Thesis in Portuguese | LILACS | ID: biblio-995936

ABSTRACT

Pacientes com queimaduras e outras lesões cutâneas de grande extensão apresentam alta propensão a infecções multirresistentes. Neste contexto, o objetivo deste trabalho é a obtenção de nanopartículas de quitosana carregadas com composto derivado de 5-nitro-heterocíclico com estrutura análoga à nifuroxazida, N'-((5-nitrofurano-2-il)metileno)-2-benzidrazida (C-H), que apresentou importante atividade frente a diversas cepas de bactérias multirresistentes. Por sua vez, a quitosana é um biopolímero com atividade antimicrobiana, analgésica, regeneradora tecidual e que, mediante contato com exsudato de lesões cutâneas forma filmes hidrogéis protetores no local de aplicação, sendo estas atividades importantes para a prevenção e tratamento de infecções e da exsudação excessiva de lesões de grande extensão. As nanopartículas de quitosana carregadas com o composto (Nps-H) foram obtidas pelo método de gelificação iônica com tripolifosfato de sódio como agente reticulante, variando a concentração de NaCl e polissorbato 80 do sistema, orientada por análise fatorial. As Nps-H obtidas foram caracterizadas por Dynamic Light Scattering (DLS) para determinação do tamanho, índice de polidispersão (IPD) e potencial zeta (ζ). A eficiência de encapsulação (EE%) foi determinada por espectrofotometria UV/VIS a 370 nm por método indireto. Entre os experimentos desenvolvidos, aquele que apresentou os melhores resultados resultou em partículas de tamanho médio de 321 d.nm, IPD 0,18, Pζ +37 mV e EE% de 48%. A morfologia e superfície das Nps-H foram analisadas por Microscopia Eletrônica de Varredura (MEV) e mostraram que as Nps-H são esféricas e de superfície irregular. A partir da obtenção e caracterização das Nps-H determinou-se a concentração inibitória mínima (CIM) das Nps-H, do composto livre (C-H) e das nanopartículas de quitosana vazias (Nps-Cs) por método colorimétrico e microdiluição frente às cepas de Staphylococcus aureus ATCC 29213, hVISA e ORSA. As Nps-H apresentaram atividade bastante superior comparando-se ao C-H e as Nps-Cs frente às cepas de S. aureus estudadas. Com vista à preparação de uma formulação farmacêutica estável, partiu-se para a liofilização das Nps-H e com esse objetivo realizou-se análises térmicas das Nps-H por Differential Scanning Calorimetric (DSC) para determinação das temperaturas de transição vítrea e eutética (Tg' e Teut) e análise por criomicroscopia para determinação da temperatura de colapso (Tcol). Amostras de Nps-H com lio/crioprotetores glicina, lactose e sacarose a diferentes concentrações foram liofilizadas a -40 ºC a 100 mTorr. As amostras de Nps-H com lactose e sacarose ambas a 2,5% e 5% demonstraram preservar as características originais das Nps-H após o processo de liofilização. Observou-se, com os resultados obtidos neste trabalho que as Nps-H representam uma promissora alternativa na prevenção e tratamento de pacientes com lesões cutâneas infeccionadas por bactérias multirresistentes e no controle da exsudação excessiva, principalmente por suas atividades terapêuticas em conjunto, diminuindo a mortalidade e morbidade desses quadros


Patients with burns and others extensive skin lesions show high propension to multiresistant infections. In this context, the aim of this project is to obtain chitosan nanoparticles carried with 5-nitro-heterocyclic derivate with structure analogue to nifuroxazide N'-((5-nitrofuran-2-yl) methylene)-2-benzhydrazide, that showed important activity against multiresistant bacteria strains. In its turn, the chitosan is a biopolymer with antimicrobial, analgesic, tecidual regenerator activities and by contact with excessive burns and extensive skin lesions exsudate process, form protective hydrogel films on place of application, being these activities important to infection and excessive exsudate treatment and prevention of extensive burns and lesions. The chitosan nanoparticles carried with compound (Nps-H) were obtained by ionic gelation method with sodium tripolyphosphate as crosslinker agent, varing the NaCl and polysorbate 80 concentrations in the system, oriented by factorial analyze. The Nps-H obtained were characterized by Dynamic Light Scattering (DLS) to size determination, polydispersion index (PDI) and zeta potential (ζ-P). The encapsulation efficiency (EE%) were determined by spectrophotometry UV/VIS at 370 nm by indirect method. Bepolissorbato the experiments developed, the one who showed the best results, resulted in particles with size of 321 d.nm, PDI of 0,18, ζ-P of +37 mV and EE% of 48%. The Nps-H morphology and surface were analyzed by Scanning Electronic Microscopy (SEM) and showed that Nps-H are spherical and with irregular surface. Starting of Nps-H obtain and characterization were determined the Nps-H, free compound (C-H) and empty chitosan nanoparticles (Nps-Cs) Minimal Inhibitory Concentrations (MIC) by colorimetric method and microdilution against Staphylococcus aureus ATCC 29213, ORSA and hVISA strains. The Nps-H showed the superior activity comparing to C-H and Nps-H against all strains tested. With a view to preparation of stable pharmaceutic formulation, started to Nps-H freeze-drying and with this aim, were realized Nps-H thermal analyzes by Differential Scanning Calorimetric (DSC) to determine glass transition and euthetic temperatures (Tg' and Teut) and the cryomicroscopy analyze to determine collapse temperature (Tcol). The Nps-H samples with lyo/cryoprotectants as glycine, lactose and sucrose at different concentrations were lyophilized at -40 ºC at 100 mTorr. The Nps-H samples with lactose and sucrose both at 2,5% and 5% demonstrated to preserve the original Nps-H characteristics after freeze-drying process. Were observed, with the results obtained in this project that Nps-H represent the promising alternative to prevention and treatment of patients with infected skin lesions by multiresitant bacteria and to control of excessive exudate process, mainly by their therapeutic activities combined, decreasing the mortality and morbidity of these cases


Subject(s)
Chitosan/analysis , Nanoparticles/classification , Anti-Infective Agents/analysis , Skin , Staphylococcus aureus/classification , Burns , Drug Discovery
15.
Pesqui. vet. bras ; 37(3): 261-268, Mar. 2017. tab, graf
Article in Portuguese | ID: biblio-842068

ABSTRACT

Este estudo isolou e determinou o perfil de sensibilidade e de resistência a antimicrobianos de cepas bacterianas isoladas da cloaca de Trachemys scripta elegans (T. s. elegans) criadas em cativeiro. Após 120 dias de adaptação, amostras de swab cloacal obtidas de 20 animais adultos foram cultivadas e, após a identificação dos patógenos através de testes bioquímicos, submetidas ao teste de suscetibilidade a nove antimicrobianos. Enterobacter aerogenes (85%); Shigella spp. (10%) e Edwadsiella spp. (5%) foram isolados e identificados. Os isolados de E. aerogenes foram sensíveis à gentamicina (86%), enrofloxacina (79%), estreptomicina (50%), sulfazotrim (36%) e ampicilina (29%) e resistentes a penicilina (100%), eritromicina (93%), cefalexina (86%) ampicilina (71%) e sulfazotrim (64%). Isolados de Shigella spp. apresentaram sensibilidade à gentamicina (100%), enrofloxacina (50%), doxicilina (50%), estreptomicina (50%), ampicilina (50%), penicilina (50%) e sulfazotrim (50%) e resistência a doxicilina (50%), estreptomicina (50%), ampicilina (50%), penicilina (100%), cefalexina (50%) e sulfazotrim (50%), enquanto que os de Edwardsiella spp. foram sensíveis apenas à gentamicina (100%) e altamente resistentes (100%) aos demais antimicrobianos. Os resultados sugerem a participação de T. s. elegans na cadeia epidemiológica, como reservatório de patógenos importantes, como E. aerogenes, Shigella spp. e Edwardisiella spp., tornando importante a adoção de medidas preventivas pelo risco zoonótico que apresentam e corretas de tratamento e de controle em cativeiros e domicílios, assim como de estudos que enfoquem as características de sensibilidade e de resistência antimicrobiana dos isolados cloacais, pois a multirresistência a drogas pode ser transmitida aos humanos e comprometer o tratamento de indivíduos com doenças graves.(AU)


This study isolated and determined the profile of susceptibility and antimicrobials resistance of bacterial strains isolated from the cloaca Trachemys scripta elegans (T. s. elegans) raised in captivity. After 120 days of adaptation, cloacal swab samples obtained from 20 adults animals were grown and, after the pathogens identification through biochemical tests, submitted to the test of susceptibility to nine antimicrobials. Enterobacter aerogenes (85%); Shigella spp. (10%) and Edwadsiella spp. (5%) were isolated and identified. Isolates from E. aerogenes were sensitive to gentamicin (86%), enrofloxacin (79%), streptomycin (50%), sulfazotrim (36%) and ampicillin (29%) and resistant to penicillin (100%), erythromycin (93%), cephalexin (86%), ampicillin (71%) and sulfazotrim (64%). Isolates from Shigella spp. showed sensitivity to gentamicin (100%), enrofloxacin (50%), doxycycline (50%), streptomycin (50%), ampicillin (50%), penicillin (50%) and sulfazotrim (50%) and resistance to doxycycline (50 %), streptomycin (50%), ampicillin (50%), penicillin (100%), cephalexin (50%) and sulfazotrim (50%), while the Edwardsiella spp. were sensitive only to gentamicin (100%) and were highly resistant (100%) to other antibiotics. The results suggest the participation of T. s. elegans in the epidemiological chain, as reservoir of important pathogens, such as E. aerogenes, Shigella spp. and Edwardisiella spp., making it important to adopt preventive measures for zoonotic risk that present and correct treatment and control in captivity and households, as well as studies that address the sensitivity characteristics and antimicrobial resistance of isolates from cloaca, as it multidrug resistance to drugs can be transmitted to humans and compromise the treatment of patients with serious diseases.(AU)


Subject(s)
Animals , Anti-Infective Agents/analysis , Drug Resistance, Bacterial , Turtles/microbiology , Edwardsiella , Enterobacter aerogenes , Microbial Sensitivity Tests/veterinary , Shigella
16.
Rev. argent. microbiol ; 49(1): 3-6, mar. 2017. ilus, tab
Article in English | LILACS | ID: biblio-1041774

ABSTRACT

Antibiotic resistance results in higher medical costs, prolonged hospital stays and increased mortality and is rising to dangerously high levels in all parts of the world. Therefore, this study aims to search for new antimicrobial agents through bioprospecting of extracts of endophytic fungi from Bauhinia guianensis, a typical Amazonian plant used in combating infections. Seventeen (17) fungi were isolated and as result the methanolic extract of the fungus Exserohilum rostratum showed good activity against the bacteria tested. The polyketide monocerin was isolated by the chromatographic technique, identified by NMR and MS, showing broad antimicrobial spectrum.


La resistencia a los antibióticos conduce a mayores costos médicos, hospitalizaciones prolongadas e incremento de la mortalidad, y está aumentando a niveles peligrosamente altos en todas partes del mundo. Este estudio tuvo como objetivo la búsqueda de nuevos agentes antimicrobianos a través de la bioprospección de extractos de hongos endófitos de Bauhinia guianensis, una planta amazónica típica, utilizada en la lucha contra problemas infecciosos. Fueron aislados 17 hongos; el extracto metanólico del hongo Exserohilum rostratum mostró buena actividad contra las bacterias probadas. Se aisló monocerina policétido por la técnica de cromatografía; este compuesto fue identificado por RM y EM, y mostró un amplio espectro antimicrobiano.


Subject(s)
Bauhinia/microbiology , Endophytes/isolation & purification , Polyketides/isolation & purification , Fungi/drug effects , Anti-Infective Agents/analysis , Anti-Bacterial Agents/analysis , Drug Resistance, Microbial/drug effects , Chromatography/methods , Bioprospecting/methods
17.
Pesqui. vet. bras ; 37(2): 97-104, fev. 2017. tab
Article in English | ID: biblio-833981

ABSTRACT

A survey of veterinary drug residues in bulk milk tank from Minas Gerais State, Brazil, was carried out through a broad scope analysis. Here, 132 raw milk samples were collected at 45 dairy farms in Minas Gerais from August 2009 to February 2010, and analyzed for 42 analytes, comprising pyrethroids, macrocyclic lactones and antibacterials, using liquid chromatography coupled with mass spectrometry in tandem mode and gas chromatography with electron capture detection. Within all milk samples, at least one veterinary drug residue was identified in 40 milk samples (30.30%) by confirmatory tests, whereas 16 samples (12.12%) showed the presence of at least two residues. With regard to the Brazilian maximum residue levels, 11 milk samples (8.33%) were non-compliant according to Brazilian Legislation. The veterinary drugs detected in the non-compliant milk samples include penicillin V (one sample), abamectin (one sample) and cypermethrin (nine samples). Furthermore, the antibacterial screening methods failed to identify most of the positive samples that were detected by confirmatory tests, leading to a large discrepancy between the screening and confirmatory antimicrobial tests. Thus, the present study indicated that the veterinary drugs residues still represents a great concern for the milk production chain.(AU)


Avaliou-se a presença de 42 analitos, incluindo piretróides, lactonas macrocíclicas e antimicrobianos em 132 amostras de leite de tanque proveniente de 45 propriedades leiteiras localizadas no Estado de Minas Gerais. Para tal, utilizou-se a cromatografia líquida acoplada a espectrofotometria de massas tandem e cromatografia gasosa com detector com captura de elétrons. Dentre todas as amostras de leite, 40 (30,30%) amostras de leite de tanque apresentaram a presença de pelo menos um analito, enquanto 16 amostras (12,12%) de leite demonstraram a presença de pelo menos dois analitos. Considerando os limites estabelecidos pela legislação brasileira, 11 amostras de leite (8,33%) seriam consideradas como não conforme. Ademais, os testes de triagem para detecção de antimicrobianos no leite não conseguiram identificar a maioria das amostras positivas nos testes confirmatórios, levando a grande discrepância entre estes testes. Desta forma, os resultados do presente estudo indicam que os períodos de descarte do leite, especialmente para piretróides, não foram plenamente respeitados por todos os produtores de leite. Além disto, uma discrepância entre os resultados dos testes confirmatórios e os testes de triagem foi observada.(AU)


Subject(s)
Anti-Infective Agents/analysis , Drug Residues/analysis , Lactones/analysis , Milk/chemistry , Pyrethrins/analysis , Anthelmintics , Cattle , Pesticides , Veterinary Drugs/analysis
18.
Braz. J. Pharm. Sci. (Online) ; 53(1): e15237, 2017. tab, graf
Article in English | LILACS | ID: biblio-839448

ABSTRACT

Abstract In the study presented here, a new series of 2-furyl(4-{4-[(substituted)sulfonyl]benzyl}-1-piperazinyl)methanone derivatives was targeted. The synthesis was initiated by the treatment of different secondary amines (1a-h) with 4-bromomethylbenzenesulfonyl chloride (2) to obtain various 1-{[4-(bromomethyl)phenyl]sulfonyl}amines (3a-h). 2-Furyl(1-piperazinyl)methanone (2-furoyl-1-piperazine; 4) was then dissolved in acetonitrile, with the addition of K2CO3, and the mixture was refluxed for activation. This activated molecule was further treated with equi-molar amounts of 3a-h to form targeted 2-furyl(4-{4-[(substituted)sulfonyl]benzyl}-1-piperazinyl)methanone derivatives (5a-h) in the same reaction set up. The structure confirmation of all the synthesized compounds was carried out by EI-MS, IR and 1H-NMR spectral analysis. The compounds showed good enzyme inhibitory activity. Compound 5h showed excellent inhibitory effect against acetyl- and butyrylcholinesterase with respective IC50 values of 2.91±0.001 and 4.35±0.004 µM, compared to eserine, a reference standard with IC50 values of 0.04±0.0001 and 0.85±0.001 µM, respectively, against these enzymes. All synthesized molecules were active against almost all Gram-positive and Gram-negative bacterial strains tested. The cytotoxicity of the molecules was also checked to determine their utility as possible therapeutic agents.


Subject(s)
Computer Simulation/statistics & numerical data , Anti-Infective Agents/analysis , Piperazines/analysis , Complement Hemolytic Activity Assay , Cholinesterases/pharmacology
19.
Braz. J. Pharm. Sci. (Online) ; 53(1): e15075, 2017. tab, graf
Article in English | LILACS | ID: biblio-839452

ABSTRACT

ABSTRACT Unsymmetrically substituted imidazolium salts were synthesized and characterized using 1H-NMR and 13C-NMR. The antimicrobial activities of the salts were evaluated using the agar-well diffusion method against 14 bacteria and five yeasts. The minimal inhibitory concentrations (MIC) against seven bacteria and one yeast were also determined. Among the test compounds applied, 1, 2, 3, 6 and 11 showed activities against Micrococcus luteus ATCC 9341, Staphylococcus aureus ATCC 25923, Staphylococcus epidermidis ATCC 12228, Bacilllus cereus ATCC 11778, Bacillus subtilis ATCC 6633, Bacillus thuringiensis, Listeria monocytogenes ATCC 19112 and Candida trophicalis. However, compounds 1, 2 and 3 showed the highest antimicrobial activities against Micrococcus luteus ATCC 9341, Stapylococcus aureus ATCC 25923, Staphylococcus epidermidis ATCC 12228, Bacilllus cereus ATCC 11778 and Bacillus subtilis ATCC 6633 with inhibition zones of 14-20 mm. In addition, compound 6 have only demonstrated activities against Candida trophicalis while compounds 4, 5, 7, 8, 9, 10, 12, 13 and 14 had no effect on test microorganisms.


Subject(s)
Salts/analysis , Imidazoles/pharmacokinetics , Anti-Infective Agents/analysis , Magnetic Resonance Spectroscopy/instrumentation , Imidazoles/metabolism
20.
Braz. J. Pharm. Sci. (Online) ; 53(4): e00076, 2017. tab, graf
Article in English | LILACS | ID: biblio-889414

ABSTRACT

ABSTRACT Considering the reported activity of carvone in the literature, this study aimed to evaluate the antimicrobial, cytotoxic and chemopreventive activities of (+)- and (-)-carvone, (+)- and (-)- hydroxydihydrocarvone and α,ß-epoxycarvone. (+)-Hydroxydihydrocarvone (HC+), (-)-hydroxydihydrocarvone (HC-) and α,ß-epoxycarvone (EP) were obtained by synthesis using (+)-carvone (C+) or (-)-carvone (C-) as precursors. The antifungal activity (MIC and MFC) were evaluated against Candida parapsilosis, C. tropicalis, C. krusei and C. albicans and the antibacterial activity (MIC and MBC) against Escherichia coli and Staphylococcus aureus. The cytotoxicity assays were performed with human cancer cell lines HepG-2 and SiHa and the normal strain MRC-5 through sulphorrodamine B assay. Chemoprevention was evaluated through quinone reductase assay. Our results showed no cytotoxicity on tumor and normal cell lines and no induction of the quinone reductase enzyme. C- and HC- presented activity against E. coli. All compounds presented weak antifungal activity against C. tropicalis and C. parapsilosis. EP and C+ showed moderate activity against C. krusei. Results suggest the potential use of carvones and its derivatives as antifungal agents against Candida yeasts. The absence of cytotoxicity in cell lines indicates safety in the use of these compounds


Subject(s)
Oils, Volatile/analysis , Chemoprevention , Carum/classification , Anti-Infective Agents/analysis , Chemoprevention , Antifungal Agents
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