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This study aimed to analyze the phytochemical profile of essential oil obtained from the leaves of Coriandrum sativum L., and its antifungal activity against Candida spp. The research consisted of an in vitro study including collecting the vegetable product, analysis of its macronutrients, extraction, and chemical analysis of the essential oil, and assaying antifungal activity through minimum inhibitory concentration (MIC) and minimum fungicidal concentration (MFC), with growth inhibition kinetics, and the product's effects on multi-species Candida biofilm. Nitrogen (47.08 g Kg-1), phosphorus (5.3 g Kg-1) and potassium (50.46 g Kg-1) levels were within the normal range. The major constituents were octanal, decanal, dec-(2E)-enal, and dodecanal. The MIC and MFC of the product evaluated against 11 tested Candida strains ranged from 31.25 to 250 µg/mL. There was inhibition of fungal growth during 24 hours of exposure at the 3 concentrations tested (250, 125, and 62.5 µg/mL). The concentration of 80 mg/mL promoted the greatest reduction in multispecies biofilm (70% reduction in biofilm). Coriandrum sativum L. essential oil extract is principally constituted of alcohols and aldehydes and presents fungicidal activity against Candida spp. in its in planktonic and biofilm forms.

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This study aimed to analyze the phytochemical profile of essential oil obtained from the leaves of Coriandrum sativum L., and its antifungal activity against Candida spp. The research consisted of an in vitro study including collecting the vegetable product, analysis of its macronutrients, extraction, and chemical analysis of the essential oil, and assaying antifungal activity through minimum inhibitory concentration (MIC) and minimum fungicidal concentration (MFC), with growth inhibition kinetics, and the product's effects on multi-species Candida biofilm. Nitrogen (47.08 g Kg-1), phosphorus (5.3 g Kg-1) and potassium (50.46 g Kg-1) levels were within the normal range. The major constituents were octanal, decanal, dec-(2E)-enal, and dodecanal. The MIC and MFC of the product evaluated against 11 tested Candida strains ranged from 31.25 to 250 µg/mL. There was inhibition of fungal growth during 24 hours of exposure at the 3 concentrations tested (250, 125, and 62.5 µg/mL). The concentration of 80 mg/mL promoted the greatest reduction in multispecies biofilm (70% reduction in biofilm). Coriandrum sativum L. essential oil extract is principally constituted of alcohols and aldehydes and presents fungicidal activity against Candida spp. in its in planktonic and biofilm forms.

Este trabalho teve como objetivo analisar o perfil fitoquímico do óleo essencial obtido das folhas de Coriandrum sativum L., e sua atividade antifúngica contra Candida spp. A pesquisa consistiu em um estudo in vitro incluindo a coleta do produto vegetal, análise de seus macronutrientes, extração e análise química do óleo essencial e ensaio da atividade antifúngica por meio da concentração inibitória mínima (CIM) e concentração fungicida mínima (MFC), com crescimento cinética de inibição e os efeitos do produto no biofilme de Candida multi-espécies. Os níveis de nitrogênio (47,08 g Kg-1), fósforo (5,3 g Kg-1) e potássio (50,46 g Kg-1) estavam dentro da normalidade. Os principais constituintes foram octanal, decanal, dec-(2E)-enal e dodecanal. A CIM e CFM do produto avaliado contra 11 cepas de Candida testadas variaram de 31,25 a 250 µg/mL. Houve inibição do crescimento fúngico durante 24 horas de exposição nas 3 concentrações testadas (250, 125 e 62,5 µg/mL). A concentração de 80 mg/mL promoveu a maior redução no biofilme multiespécies (redução de 70% no biofilme). O extrato do óleo essencial de Coriandrum sativum L. é constituído principalmente por álcoois e aldeídos e apresenta atividade fungicida contra Candida spp. em suas formas planctônicas e biofilme.

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Staphylococcus aureus is one of the main pathogens found in cheeses produced with raw milk, including Minas artisanal cheese from Brazil. However, information about S. aureus isolated from artisanal cheeses and its sources of production in small-scale dairies is very limited. We aimed to characterize the virulence factors of S. aureus isolated from raw milk, endogenous starter culture, Minas artisanal cheese, and cheese handlers from the region of Campo das Vertentes, Minas Gerais, Brazil. We identified the staphylococcal isolates by MALDI-TOF mass spectrometry. We evaluated biofilm production on Congo red agar and polystyrene plates. We used PCR to detect icaA, icaB, icaC, sea, seb, sec, sed, see, tsst-1, agr, and mecA. We evaluated the expression of staphylococcal toxin genes in PCR-positive staphylococcal isolates using quantitative reverse-transcription PCR, and we evaluated the production of these toxins and their hemolytic activity in vitro. We also evaluated the antimicrobial resistance profile of the staphylococcal isolates. For statistical analysis, we used cluster analysis, χ2 tests, and correspondence tests. We analyzed 76 staphylococcal isolates. According to PCR, 18.42, 18.42, 2.63, and 77.63% were positive for sea, tsst-1, sec, and agr, respectively. We found low expression of staphylococcal toxin genes according to quantitative reverse-transcription PCR, and only 2 staphylococcal isolates produced toxic shock syndrome toxins. A total of 43 staphylococcal isolates (56.58%) had hemolytic activity; 53 were biofilm-forming on Congo red agar (69.73%), and 62 on polystyrene plates (81.58%). None of the staphylococcal isolates expressed the mecA gene, and none presented a multi-drug resistance pattern. The highest resistance was observed for penicillin G (67.11%) in 51 isolates and for tetracycline (27.63%) in 21 isolates. The staphylococcal isolates we evaluated had toxigenic potential, with a higher prevalence of sea and tsst-1. Biofilm production was the main virulence factor of the studied bacteria. Six clusters were formed whose distribution frequencies differed for hemolytic activity, biofilm formation (qualitative and quantitative analyses), and resistance to penicillin, tetracycline, and erythromycin. These findings emphasize the need for effective measures to prevent staphylococcal food poisoning by limiting S. aureus growth and enterotoxin formation throughout the food production chain and the final product.

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AIM: To evaluate the activity and effectiveness of impregnated central venous catheters (CVC) against Klebsiella pneumoniae biofilms. METHODS AND RESULTS: The antimicrobial activity and durability of impregnated-CVCs were evaluated over time and the size of zones of inhibition (ZI) was measured. Biofilm formation was observed by quantitative culture and also by scanning electron microscopy. The catheters impregnated with chlorhexidine/silver sulfadiazine (CHX/SS) reduced bacteria counts by 0·3 log and were most effective (P < 0·01) against Klebsiella pneumoniae biofilms N-acetylcysteine/levofloxacin (NAC/LEV) catheters. It was observed that the catheter impregnated with NAC/LEV had initially the largest average ZI size being statistically significant (P < 0·01). The NAC/LEV combination remained active until day 30, whereas the combination of CHX/SS was completely inactivated from day 15 on. CONCLUSIONS: The NAC/LEV combination showed greater durability on the catheters, but it was the CHX/SS combination that had the greater initial efficacy in bacterial inhibition. It was also observed that NAC/LEV-impregnated catheters do not prevent the emergence of resistant subpopulations inside the inhibition halos during antimicrobial susceptibility tests. SIGNIFICANCE AND IMPACT OF THE STUDY: Our results highlighted that the in vitro efficacy of antimicrobial-impregnated CVCs is limited by time and that their colonization occurred earlier than expected. Our data also demonstrated that NAC/LEV remained active until day 30 of evaluation and CHX/SS combination was completely inactivated from day 15 on. Our findings suggested that implantable devices should be carefully used by medical community.

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Infectious wastes are potential sources of pathogenic micro-organisms, which may represent a risk to the professionals who manage them. In this study, we aimed to characterize the infectious bacteria present in dental waste and waste workers. The dental waste produced over 24 h was collected and waste workers were sampled by swabbing. Isolate resistance profiles were characterized by Vitek® and PCR and biofilm formation by Congo Red agar, string test and microtitre assay. To assess similarity between the waste and the workers' samples, a random amplified polymorphic DNA test was used. Twenty-eight bacteria were identified as clinically relevant. The most frequent gene was blaTEM present in five Gram-negative micro-organisms, and one blaSHV in Klebsiella pneumoniae. All Pseudomonas aeruginosa were positive to extracellular polymeric substances formation, except one isolated from a worker. Klebsiella pneumoniae had negative results for the string test. Pseudomonas aeruginosa showed better adherence at 25°C after 48 h of incubation and K. pneumonia had the best biofilm formation at the same temperature, after 24 h. The similarity between P. aeruginosa recovered from dental waste and from workers was low, however, it is important to note that a pathogen was found on a worker's hands and that improvements in biosafety are required. SIGNIFICANCE AND IMPACT OF THE STUDY: Infectious dental waste can contain clinically relevant bacteria with important resistance and biofilm profiles. These micro-organisms could be transmitted to waste workers, other professionals and patients if the principles of biosafety measures are neglected. To our knowledge, no study has ever evaluated the microbial characterization and the potential contamination risk of dental infectious waste and waste handlers. The presence of clinically relevant bacteria in the hands and nasal mucosa of waste workers highlights the need for studies in this field to clarify the risk of these pathogens in dental healthcare services, and to stress the need for an efficient waste management.

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Coagulase-negative staphylococci (CNS) represent one of the most prevalent microorganisms in nosocomial infections worldwide, nevertheless little is known about their pathogenicity features. Thus, our aim was to characterize virulence aspects of CNS isolated from patients with bloodstream infections assisted in hospitals of Belo Horizonte, MG, Brazil. Strains were identified using bioMérieuxVitek® and for biofilm production evaluation, Congo Red Agar (CRA) and polystyrene plates were used. PCR was applied to detect icaA, icaB, icaC, atlE, sea, sec, sed, tsst-1 and agr. For statistical analyses were used hierarchical cluster, chi-square test and correspondence. 59 strains were analyzed, being S. haemolyticus the most prevalent. On CRA, 96.5% were biofilm producer, whereas on polystyrene plate, 100% showed adhesion at different times evaluated. Regarding genotypic analyses, 15.2%, 38.9%, 8.4%, 49.1%, 76.2%, 23.7%, 1.6%, 30.5% and 38.9% were positive for icaA, icaB, icaC, atlE, sea, sec, sed, tsst-1 and agr, respectively. Six clusters were formed and frequency distributions of agr, atlE, icaA, icaB, sea, sec, tsst-1 differed (P < 0.001). In conclusion, all strains were biofilm producer, with high prevalence of atlE, and had potential of toxin production, with high prevalence of sea. According to the group-analyses, icaB showed relationship with the strong adherence in samples.

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ETHNOPHARMACOLOGICAL RELEVANCE: Hyptis suaveolens is used by the traditional population in several parts of the world to treat inflammation, gastric ulcer and infection and is used as a crude drug to relieve symptoms related with gastric ulcer or gastritis in northeaster and central region of Brazil. MATERIALS AND METHODS: the standardized ethanolic extract (Hs-EtOHE) and hexanic fraction (Hs-HexF) of Hyptis suaveolens (62,5, 125, 250 and 500 mg/kg) was evaluated in several models of acute gastric ulcers. The participation of NO was evaluated by pretreatment with L-NAME and non-protein sulfyhydryls by NEM in the gastroprotective effect. RESULTS: Hs-EtOHE and Hs-HexF markedly reduced the gastric lesions induced by all ulcerogenic agents (HCl/ethanol, ethanol, NSAIDs and hypothermic restraint-stress). Gastric ulcerations were exacerbated by administration of NEM suggesting that the gastroprotective mechanism of action of Hs-EtOHE and Hs-HexF involves sulfhydryl groups. CONCLUSION: Ours results show that an extract of Hyptis suaveolens, administered orally to rodents, present gastro protective activity in different models of acute of gastric ulcer and give some support to the reported claims on the use of this plant as a gastro protective agent.

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The production of Toxic Shock Syndrome Toxin-1 (TSST-1), enterotoxins and bacteriocin-like substances was evaluated in 95 strains of Staphylococcus aureus recovered from raw bovine milk (n=31) and from food samples involved in staphylococcal food poisoning (n=64). Enterotoxigenicity tests with the membrane over agar associated to optimal sensibility plate assays were performed and showed that 96.77% of strains recovered from milk and 95.31% from food samples produced enterotoxins A, B, C, D or TSST-1. Reference strains S. epidermidis, Bacillus cereus, Listeria monocytogenes, Lactobacillus casei, Pseudomonas aeruginosa, S. aureus, Salmonella Typhimurium, Escherichia coli, Enterococcus faecalis and Bacteroides fragilis were used as indicator bacteria in the antagonistic assays, the first five being sensitive to antagonistic substances. Brain heart infusion agar, in pH values ranging from 5.0 to 7.0 in aerobic atmosphere showed to be the optimum condition for antagonistic activity as evaluated with the best producer strains against the most sensitive indicator bacterium, L. monocytogenes. Sensitivity to enzymes confirmed the proteinaceous nature of these substances. Neither bacteriophage activity nor fatty acids were detected and the antagonistic activity was not due to residual chloroform. Results did not establish a positive correlation between the bacteriocinogenic profile and toxigenicity in the tested S. aureus strains.

Avaliou-se a produção de toxina-1 da síndrome do choque tóxico (TSST-1), enterotoxinas e substâncias antagonistas tipo bacteriocina em 95 amostras de Staphylococcus aureus recuperadas de leite bovino in natura (n=31) e de alimentos envolvidos em surto de intoxicação (n=64). Testes de enterotoxigenicidade pelo método da membrana sobre ágar, associado à técnica da sensibilidade ótima em placa, revelaram que 96,77% das amostras do leite e 95,31% daquelas dos alimentos produziram enterotoxinas estafilocócicas tipos A, B, C, D ou TSST-1. Nos ensaios de antagonismo, foram utilizadas como reveladoras amostras de referência de S. epidermidis, Bacillus cereus, Listeria monocytogenes, Lactobacillus casei, Pseudomonas aeruginosa, S. aureus, Salmonella typhimurium, Escherichia coli, Enterococcus faecalis e Bacteroides fragilis, sendo as cinco primeiras sensíveis às substâncias produzidas. As condições ótimas para a atividade antagonista, avaliadas com as melhores produtoras contra a indicadora mais sensível, L. monocytogenes, foram observadas em aerobiose, em ágar infuso de cérebro-coração, nos valores de pH entre 5,0 e 7,0. A sensibilidade a enzimas confirmou a natureza proteica destas substâncias. Não foram detectadas atividades de bacteriófagos nem de ácidos graxos, e a atividade antagonista não foi devido ao clorofórmio residual. Os resultados não mostraram correlação entre o perfil bacteriocinogênico e a toxigenicidade nas amostras de Staphylococcus testadas.

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The production of Toxic Shock Syndrome Toxin-1 (TSST-1), enterotoxins and bacteriocin-like substances was evaluated in 95 strains of Staphylococcus aureus recovered from raw bovine milk (n=31) and from food samples involved in staphylococcal food poisoning (n=64). Enterotoxigenicity tests with the membrane over agar associated to optimal sensibility plate assays were performed and showed that 96.77% of strains recovered from milk and 95.31% from food samples produced enterotoxins A, B, C, D or TSST-1. Reference strains S. epidermidis, Bacillus cereus, Listeria monocytogenes, Lactobacillus casei, Pseudomonas aeruginosa, S. aureus, Salmonella Typhimurium, Escherichia coli, Enterococcus faecalis and Bacteroides fragilis were used as indicator bacteria in the antagonistic assays, the first five being sensitive to antagonistic substances. Brain heart infusion agar, in pH values ranging from 5.0 to 7.0 in aerobic atmosphere showed to be the optimum condition for antagonistic activity as evaluated with the best producer strains against the most sensitive indicator bacterium, L. monocytogenes. Sensitivity to enzymes confirmed the proteinaceous nature of these substances. Neither bacteriophage activity nor fatty acids were detected and the antagonistic activity was not due to residual chloroform. Results did not establish a positive correlation between the bacteriocinogenic profile and toxigenicity in the tested S. aureus strains.(AU)

Avaliou-se a produção de toxina-1 da síndrome do choque tóxico (TSST-1), enterotoxinas e substâncias antagonistas tipo bacteriocina em 95 amostras de Staphylococcus aureus recuperadas de leite bovino in natura (n=31) e de alimentos envolvidos em surto de intoxicação (n=64). Testes de enterotoxigenicidade pelo método da membrana sobre ágar, associado à técnica da sensibilidade ótima em placa, revelaram que 96,77% das amostras do leite e 95,31% daquelas dos alimentos produziram enterotoxinas estafilocócicas tipos A, B, C, D ou TSST-1. Nos ensaios de antagonismo, foram utilizadas como reveladoras amostras de referência de S. epidermidis, Bacillus cereus, Listeria monocytogenes, Lactobacillus casei, Pseudomonas aeruginosa, S. aureus, Salmonella typhimurium, Escherichia coli, Enterococcus faecalis e Bacteroides fragilis, sendo as cinco primeiras sensíveis às substâncias produzidas. As condições ótimas para a atividade antagonista, avaliadas com as melhores produtoras contra a indicadora mais sensível, L. monocytogenes, foram observadas em aerobiose, em ágar infuso de cérebro-coração, nos valores de pH entre 5,0 e 7,0. A sensibilidade a enzimas confirmou a natureza proteica destas substâncias. Não foram detectadas atividades de bacteriófagos nem de ácidos graxos, e a atividade antagonista não foi devido ao clorofórmio residual. Os resultados não mostraram correlação entre o perfil bacteriocinogênico e a toxigenicidade nas amostras de Staphylococcus testadas.(AU)

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AIMS: This study was undertaken to detect, identify and determine antifungal susceptibility of yeast strains isolated from dental solid waste and to evaluate airborne fungi in the Brazilian dental health care environment and in the waste storage room. METHODS AND RESULTS: A group of 17 yeast strains were identified by macroscopic and microscopic characteristics, API 20C Aux system and Multiplex PCR. All 104 airborne fungal colonies were identified by macroscopic and microscopic morphology. The CLSI broth microdilution method was utilized as the susceptibility test. Candida parapsilosis was the prevailing yeast species recovered from waste, followed by Rhodotorula glutinis. Three strains of Candida guilliermondii presented minimal inhibitory concentration values considered to be susceptible dose dependent (2 µg ml(-1)) to voriconazole. Of all airborne fungal species, 69% were recovered from the waste storage room and 31% were recovered from the clinical/surgical environment. Most of them were identified as Cladosporium spp. CONCLUSIONS: These findings reinforce the potential risk of waste handling and point out the need for safe management to minimize the spread of these agents to the environment. Filamentous fungi isolation in almost all sampled environments indicates that a periodic monitoring of airborne microbiota in the dental health care service environment is required. SIGNIFICANCE AND IMPACT OF THE STUDY: The survival of yeast strains for 48 h suggests that dental waste should be carefully controlled and monitored.

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