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1.
J Biotechnol ; 351: 109-121, 2022 Jun 10.
Article in English | MEDLINE | ID: mdl-35500704

ABSTRACT

Biosurfactants are capable of meeting the challenges of the oil industry by reducing its social, economic, and environmental impacts. The aim of the present study was to produce a biosurfactant from Pseudomonas cepacia CCT6659 in 2.0-L and 5.0-L bioreactors and evaluate its long-term stability over 120 days of storage. Ecotoxicological tests were performed with Artemia salina larvae during the use of the biosurfactant to increase in solubilisation of heavy oil in seawater compared to the use of a chemical surfactant. The biosurfactant was also applied as a bioremediation agent for sand contaminated with a petroleum product and as an inhibitor of corrosion on metallic surfaces. A concentration of 35.0 g/L of the biosurfactant was achieved in the 5.0-L reactor and low toxicity to the bioindicator was found, with an approximate 40% reduction in the mortality rate compared to the chemical surfactant. The stability of the biosurfactant was demonstrated by the maintenance of its tensioactive properties throughout the entire storage period. Besides its advantageous bioremediating capacity, with the removal of 94.5% of oil from sand, the biosurfactant proved to be an effective inhibitor of both metallic corrosion and microbial biofilm, with minimal loss of mass (15.7%) compared to the control condition, demonstrating its potential for industrial applications.


Subject(s)
Burkholderia cepacia , Petroleum , Biodegradation, Environmental , Corrosion , Sand , Surface-Active Agents/chemistry , Surface-Active Agents/pharmacology
2.
Food Res Int ; 122: 450-460, 2019 08.
Article in English | MEDLINE | ID: mdl-31229099

ABSTRACT

The aim of this study was to identify the phenotypic and genotypic profiles of Staphylococcus spp. isolated from mastitis milk and cheese processing plant.To evaluate the biofilm production of wild-type strains on contact surfaces by testing different factors through adhered cells and biofilm quantifications, finally, these biofilms were observed by Scanning Electron Microscopy (SEM). Congo red agar (CRA) plate method was used to identify slime production by strains. Screening of genes encoding adhesion factors and biofilm formation was carried out using PCR. After strains selection, adhesion and biofilm assays were designed testing different times (12, 48, 96 h), strains (n = 13), contact surfaces (stainless steel and polypropylene), and temperatures (5 °C and 25 °C); and then, bacterial count and crystal violet staining were conducted. Relative frequencies of positive on CRA and genes presence were determined, and Friedman test was applied for bacterial counts and OD values. Additionally, significant factors (P ≤ .05) were subjected to multiple comparisons using the Nemenyi test. The slime production in CRA was observed by visual inspection in 38.7% of strains. A large distribution of genes was described among strains, implying a high variability of genotypic profiles. Moreover, relative frequencies of CRA positive and gene presence were described. The developed assay showed that the strain, temperature, contact surface, were significant for both variables. The SEM corroborated the findings, showing greater biofilm formation on stainless steel at 25 °C. Thus, it is essential to highlight the importance of temperature control and material with low superficial energy to avoid biofilm formation by staphylococci.


Subject(s)
Bacterial Adhesion , Cheese/microbiology , Food Handling , Milk/microbiology , Staphylococcus/isolation & purification , Animals , Biofilms , Colony Count, Microbial , Culture Media , Food Contamination , Food Microbiology , Genes, Bacterial , Genotype , Microscopy, Electron, Scanning , Phenotype , Polypropylenes/chemistry , Stainless Steel/chemistry , Staphylococcus/metabolism , Temperature
3.
Comun. ciênc. saúde ; 28(3-4): 313-325, jul. 2017. tab
Article in Portuguese | LILACS | ID: biblio-972680

ABSTRACT

INTRODUÇÃO: As Parcerias para o Desenvolvimento Produtivo (PDP) são uma prática inovadora do Estado brasileiro. Usando o poder de compra da saúde, essas parcerias visam o desenvolvimento do Complexo Econômico Industrial da Saúde e a ampliação do acesso da população a produtos estratégicos. OBJETIVO: apresentar o diagnóstico situacional das PDP a partir da percepção dos atores envolvidos e recomendações para o aprimoramento da iniciativa. MÉTODOS: Foi realizado um inquérito com aplicação de questionários eletrônicos a atores envolvidos com as PDP, seguido de análise quali e quantitativa. Foram utilizadas as dimensões do Octógono da Inovação, um instrumento proprietário da Innoscience - Consultoria de Gestão da Inovação, para estruturar o questionário e a análise de dados. RESULTADOS: Obteve-se taxa de resposta de 51% (41/81), sendo 17 envios provenientes de produtores públicos, 10 de entidades privadas e 14 do setor governamental. As respostas foram organizadas e analisadas segundo as dimensões estratégia, pessoas, cultura, liderança, funding, relacionamento, estrutura e processos, e, a partir destas, foram identificadas fragilidades na implementação das PDP, bem como recomendações para aplicação prática pela governança para aprimoramento da iniciativa, inclusive nos instrumentos de monitoramento gerencial existentes e nos recursos disponíveis para essa ação. CONCLUSÕES: Os achados deste diagnóstico podem contribuir para apoiar a governança na continuidade e melhorias das PDP, além de apoiar novos estudos relacionados à avaliação dessa iniciativa inovadora no Brasil.


INTRODUCTION: Productive Development Partnerships (PDP) are an innovative practice of the Brazilian State. Using the purchasing power of health care sphere, these partnerships aim the development of the economic and industrial health care complex and the widening the population access to strategic products. OBJECTIVE: To present a situational diagnosis of PDP from the perspective of the actors involved and recommendations for enhancement of the initiative. METHODS: An inquiry with an electronic survey was applied to actors involved in PDP, followed by qualitative and quantitative analysis. The dimensions from the Octagon of Innovation, an instrument owned by Innoscience - Innovation Management Consulting, were used in order to structure the survey and analyze the data. RESULTS: A response rate of 51% (41/81) was obtained, with 17 of the submissions coming from public manufacturers, 10 from private entities and 14 from the government sector. The responses were organized and analyzed according to the following dimensions: strategy, people, culture, leadership, funding, relationship, structure, processes and henceforth. The fragilities in the PDP implementation process were identified as well as recommendations for the practical applications by the governance in order to enhance the initiative, including existing management monitoring instruments and resources available for this action. CONCLUSIONS: The findings of this diagnosis can contribute to support governance in the continuity and improvement of PDP, besides supporting new studies related to the evaluation of this innovativeinitiative in Brazil.


Subject(s)
Humans , Technological Development and Innovation Projects
4.
PLoS Negl Trop Dis ; 11(4): e0005525, 2017 04.
Article in English | MEDLINE | ID: mdl-28379952

ABSTRACT

BACKGROUND: Digestion of blood in the midgut of Aedes aegypti results in the release of pro-oxidant molecules that can be toxic to the mosquito. We hypothesized that after a blood meal, the antioxidant capacity of the midgut is increased to protect cells against oxidative stress. Concomitantly, pathogens present in the blood ingested by mosquitoes, such as the arboviruses Dengue and Zika, also have to overcome the same oxidative challenge, and the antioxidant program induced by the insect is likely to influence infection status of the mosquito and its vectorial competence. METHODOLOGY/PRINCIPAL FINDINGS: We found that blood-induced catalase mRNA and activity in the midgut peaked 24 h after feeding and returned to basal levels after the completion of digestion. RNAi-mediated silencing of catalase (AAEL013407-RB) reduced enzyme activity in the midgut epithelia, increased H2O2 leakage and decreased fecundity and lifespan when mosquitoes were fed H2O2. When infected with Dengue 4 and Zika virus, catalase-silenced mosquitoes showed no alteration in infection intensity (number of plaque forming units/midgut) 7 days after the infectious meal. However, catalase knockdown reduced Dengue 4, but not Zika, infection prevalence (percent of infected midguts). CONCLUSION/SIGNIFICANCE: Here, we showed that blood ingestion triggers an antioxidant response in the midgut through the induction of catalase. This protection facilitates the establishment of Dengue virus in the midgut. Importantly, this mechanism appears to be specific for Dengue because catalase silencing did not change Zika virus prevalence. In summary, our data suggest that redox balance in the midgut modulates mosquito vectorial competence to arboviral infections.


Subject(s)
Aedes/enzymology , Catalase/metabolism , Dengue Virus/physiology , Dengue/transmission , Insect Vectors/enzymology , Zika Virus/physiology , Aedes/physiology , Aedes/virology , Animals , Blood , Catalase/genetics , Female , Gastrointestinal Tract/enzymology , Gastrointestinal Tract/virology , Hydrogen Peroxide/analysis , Hydrogen Peroxide/metabolism , Insect Proteins/genetics , Insect Proteins/metabolism , Insect Vectors/physiology , Insect Vectors/virology , Oxidative Stress , RNA Interference , Rabbits , Zika Virus Infection/transmission
5.
Arq. ciências saúde UNIPAR ; 20(3): 151-158, set.-dez. 2016.
Article in Portuguese | LILACS | ID: biblio-832965

ABSTRACT

O interesse em terapias alternativas e o uso terapêutico por derivados de plantas vêm crescendo nos últimos anos, obtendo um grande avanço científico no aspecto químico e farmacológico, a Organização Mundial da Saúde (OMS), considera as plantas medicinais como importantes instrumentos da assistência farmacêutica. Objetivo: Determinar atividade antibacteriana comparada entre os extratos de Senna spectabilis, Rosmarinus officinalis e Eugenia uniflora frente à cepa padrão de Pseudomonas aeruginosa ATCC 27853, Staphylococcus aureus ATCC 6538 e Streptococcus pyogenes ATCC 19615. As folhas de E. uniflora, R. officinallis e S. spectabilis foram coletadas no Horto de plantas medicinais da Universidade Estadual de Maringá ­ UEM/PR e as cepas foram fornecidas pela Universidade Paranaense ­ Unipar. A atividade antibacteriana foi determinada por meio da técnica do microdiluição em placa, empregando revelador de crescimento Alamar Blue Assay (MABA). A concentração mínima inibitória (CIM) empregando R. officinalis, E. uniflora, frente a cepa de S. aureus ATCC pode revelar resultados de 125 µg/mL, para extratos de S. spectabilis o CIM foi de 250 µg/mL; para S. pyogenes o CIM de 125 µg/mL foi admitido apenas para R. officinalis e S. spectabilis, E. uniflora apresentou resultados de 500 µg/mL, para P. aeruginosa o CIM para os três extratos foi superior a 500 µg/mL. Os extratos são promissores quando empregados contra S. aureus e S. pyogenes, exceto para P. aeruginosa, no entanto cabe buscar novas alternativas para tratamento deste Gram-negativo.


The interest in alternative therapies and therapeutic use of plant extracts has been increasing in recent years, and has had great scientific advances regarding the chemical and pharmacological aspects. The World Health Organization (WHO) considers medicinal plants as important pharmaceutical care instruments. In order to determine the compared antibacterial activity between Senna spectabilis, Rosmarinus officinalis and Eugenia uniflora extracts against standard strains of Pseudomonas aeruginosa ATCC 27853, Staphylococcus aureus ATCC 6538 and Streptococcus pyogenes ATCC 19615, the leaves of E. uniflora, R.officinallis and S. spectabilis were collected in the medicinal plant garden of the State University of Maringa - UEM/PR, and strains were provided by University Paranaense - Unipar. The antibacterial activity was determined by broth microdilution plate technique using Alamar Blue Assay (MABA) growth revelant. The minimum inhibitory concentration (MIC) using R. officinalis, E. uniflora against the S. aureus ATCC strain revealed results of 125 µg/mL, for S. spectabilis extracts, MIC was of 250 µg/mL; S. pyogenes resulted in a MIC of 125 µg/mL was admitted only for R. officinalis and S. spectabilis, E. uniflora results showed 500 µg/mL, and for P. aeruginosa, MIC was greater than 500 µm/mL for the three extracts. The extracts are considered as promising when used against S. aureus and S. pyogenes, but not for P. aeruginosa. However, new alternatives are being sought for treating this gram-negative strain.


Subject(s)
Plant Extracts/pharmacology , Senna Plant/chemistry , Rosmarinus/chemistry , Eugenia/chemistry , Gram-Positive Bacteria/drug effects , Anti-Bacterial Agents/pharmacology , Plants, Medicinal , Pseudomonas aeruginosa/drug effects , Staphylococcus aureus/drug effects , Streptococcus pyogenes/drug effects , Microbial Sensitivity Tests
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