01. Universidade Federal Rural de Pernambuco - UFRPE (Sede)
URI permanente desta comunidadehttps://arandu.ufrpe.br/handle/123456789/1
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Item Investigação do extrato de cladódios de Cereus jamacaru quanto à composição química, potencial antimicrobiano contra Staphylococcus aureus e efeito larvicida para Aedes aegypti(2023-09-21) Guimarães, Júlia Maria Rodrigues; Pontual, Emmanuel Viana; Alves, João Victor de Oliveira; http://lattes.cnpq.br/0882174483226946; http://lattes.cnpq.br/1777060469196142; http://lattes.cnpq.br/3701748857935689Cereus jamacaru (Cactaceae), mandacaru, is a plant from the Brazilian semi-arid region that has economic importance for livestock farming and use in folk medicine. The use of currently commercialized antibiotics leads to many unwanted effects and has led to the emergence of resistant bacteria, while synthetic insecticides generally have high persistence in the environment and strong non-target toxicity. In this sense, the search for new antimicrobial agents and insecticides has grown. The aim of this work was to investigate the cladode extract of C. jamacaru regarding its chemical composition (presence of lectins, protease inhibitors and secondary metabolites), antimicrobial potential against pathogenic bacteria and larvicidal effect against Aedes aegypti. Cladodes of C. jamacaru were collected in Recife, Pernambuco. The spines were removed and the cladodes were cut into slices and air-dried (28°C, 4 days). Then, the cladodes were crushed and the powder (10 g) was homogenized (28°C, 16 h) with 0.15 M NaCl solution (100 mL) in water, using a magnetic stirrer. The mixture was filtered and centrifuged (3,000 g, 15 min) and the clear supernatant corresponded to cladode extract (CjCE) which was investigated for the presence of lectins using rabbit erythrocytes, protease inhibitor using bovine trypsin (0.1 mg/ mL) and the chromogenic and peptidomimetic substrate BApNA (8 mM), and secondary metabolites by thin layer chromatography. The content of phenolic compounds in CjCE was determined using the Folin-Ciocalteu reagent (10%, v/v) and a gallic acid standard curve, while flavonoids were quantified using the aluminum chloride reagent (20%, m/v) and quercetin as standard. Then, the extract was investigated for antioxidant activity using the DPPH, ABTS and Phosphomolybdenum methods. The antibacterial potential of CjCE was determined using bacterial strains sensitive or resistant to antibiotics by the plate microdilution method. The minimum inhibitory concentration (MIC, lowest concentration of CjCE capable of inhibiting bacterial growth by 50%) was determined. Hemolysis assay by S. aureus was performed using human erythrocytes and the effect of CjCE (128, 64 and 32 µg/mL) on hemolysis was investigated. The larvicidal potential of CjCE (0.40 to 3.5%, m/v) was evaluated by treatment (48 h) of A. aegypti larvae in the third instar (L3). CjCE caused agglutination of rabbit erythrocytes (8 UAH), suggesting the presence of lectins. The extract reduced the hydrolysis of the BApNA substrate by trypsin, indicating the presence of a protease inhibitor. CjCE thin layer chromatography revealed the presence of reducing sugars and qualitative-quantitative analysis showed 40.20±0.97 mgEAG/g of total phenols, among which, 3.36±0.07 mgEAG/g (8, 36%) were flavonoids. CjCE showed relevant oxidant activity, with the ability to scavenge ABTS and DPPH radicals (IC50 of 3,735 µg/mL and 2704.50 µg/mL, respectively), but was not able to cause reduction of phosphomolybdenum. CjCE was toxic only to the Staphylococcus aureus strain (UFPEDA 02), revealing a strong bacteriostatic effect (MIC of 199.09±0.85 µg/mL), and reduced erythrocyte lysis caused by the bacteria by more than 90%, compared to to control. The treatment of L3 of Ae. aegypti with CjCE resulted in dose-dependent mortality (LC50 = 0.68%, m/v). On the other hand, when larvae were treated with CjCE at a concentration 10 times higher than the LC50, the intestinal contents covered by the peritrophic membrane were eliminated in an attempt to eliminate the toxic components of the extract. In conclusion, C. jamacaru cladode extract is a novel antimicrobial agent capable of strongly inhibiting the growth of S. aureus and reducing bacterial toxicity to human erythrocytes. Furthermore, the toxicity to A. aegypti larvae shown here points to the C. jamacaru cladode extract as an interesting starting material for obtaining larvicidal formulations. The antibacterial and insecticidal effects of the extract may be linked to the presence of lectins, protease inhibitors and phenolic compounds.Item Atividade antimicrobiana de óleos essenciais de orégano (Origanum vulgare), pimenta rosa (Schinus terebinthifolia) e melaleuca (Melaleuca alternifólia) frente aos patógenos de origem alimentar(2024-02-21) Silva, Esterfani Pereira da; Soares, Luciana Felizardo Pereira; http://lattes.cnpq.br/4071178363761831; http://lattes.cnpq.br/3144149210017027In recent years, the use of synthetic additives to prevent food spoilage by microorganisms has been a worrying factor for the food industry, given their negative impact on consumer health. In order to overcome this impasse, essential oils have emerged as an alternative, containing compounds and active principles that inhibit the development of microorganisms. The aim of this study was to evaluate the minimum inhibitory concentration (MIC) and minimum bactericidal concentration (MBC) of the commercially obtained essential oils of Tea tree (Melaleuca alternifolia), Oregano (Origanum vulgare) and Pink pepper (Schinus terebinthifolia). For the study, bacterial isolates at a concentration of 3.5 x 107 CFU/ml (0.5 on the Mc Farland scale) of Staphylococcus aureus (ATCC 25923) and Escherichia coli (ATCC 25922) obtained commercially from the American Type Culture Collection were used. The incubated plates were visually analyzed to determine the minimum inhibitory concentration (MIC). In the wells where inhibition of bacterial growth was observed, 20 μL of the suspensions were collected and sown on Mueller-Hinton agar plates in an oven at 37ºC for 24 hours to analyze bacterial growth and determine the minimum bactericidal concentration (MBC). The mean MIC values for oregano, pink pepper and tea tree essential oils were 2500 μg/ml, 650 μg/ml and 500 μg/ml for the E. coli strains, respectively, while the minimum inhibitory concentration of the treatments was 500 μg/ml for the S. aureus bacterial group. As far as CBM is concerned, the average concentrations for the essential oils of oregano, pink pepper and tea tree were 2500 μg/ml, 625 μg/ml and 5000 μg/ml for the E. coli strains and 1250 μg/ml, 2500 μg/ml and 625 μg/ml for the gram-positive bacteria S. aureus, respectively.Item Análise de mecanismos de resistência em bactérias clínicas oriundas de hospitais de Pernambuco(2021-02-17) Silva, Jonas de Melo Silvestre da; Almeida, Anna Carolina Soares; http://lattes.cnpq.br/4891800920829895; http://lattes.cnpq.br/9044602995334190The spread of resistant bacteria or superbugs has been considered a catastrophic threat to the health of the population and represents one of the main challenges in the area of health worldwide. This work's main objective is to identify genetic and molecular determinants, resistance mechanisms, and the clonal relationship between twenty-two isolates obtained from two hospitals in Pernambuco. Isolates of: Klebsiella pneumoniae, Klebsiella ozaenae, Escherichia coli, and Enterobacter spp were included, all of which showed a phenotypic profile of multidrug resistance (MDR). Isolates from the University Hospital of the Federal University of Vale do São Francisco had a higher resistance profile compared to isolates from the University Hospital Oswaldo Cruz located in Recife, mainly to aminoglycosides and 3rd and 4th generation cephalosporins. Using the polymerase chain reaction (PCR) technique, it was possible to detect at least one of the B-lactam resistance genes tested in all isolates, except for 2 isolates that did not present any of the genes evaluated. The blaCTX-M gene was the most prevalent found in this study. And despite half of the samples having a resistance profile to carbapenems, the blaKPC gene was the least detected. In addition, clonal relationship analysis using the REP-PCR technique revealed a possible endemicity of a single clonal type in the Intensive Care Unit at Hospital Universitário Oswaldo Cruz located in Recife. At the University Hospital of the Federal University of Vale do São Francisco, the establishment of two clonal groups that have been disseminated for at least 3 months was identified. The presence of multiresistant bacteria in hospital units reinforces the need for strategies to contain infections and spread these pathogens, especially in ICUs.Item Análise da suceptibilidade aos antimicrobianos em Pseudomonas spp. isoladas de produtos saneantes(2020-02-03) Vitor, Mizânia Cabral de Almeida; Almeida, Anna Carolina Soares; Souza, Paula Mariana Salgueiro de; http://lattes.cnpq.br/6281410502740086; http://lattes.cnpq.br/4891800920829895Item Emprego de antimicrobianos na pecuária bovina e suas implicações na saúde pública(2021-12-15) Gomes, Lucas da Silva Ferreira; Coutinho, Luiz Teles; http://lattes.cnpq.br/8812254003382110; http://lattes.cnpq.br/6350534197203776The use of antimicrobials (ATM) in ruminants is a tool responsible for a significant boost in animal production by reducing morbidity and mortality rates arising from health problems, thus providing an improvement in the health profile and production rates, and consequently greater quality and safety of animal foods. However, the high adaptability of the bacterial cell associated with the selective pressure imposed by the indiscriminate use of ATM's in animals and also in humans, has been promoting the development of antimicrobial resistance (AMR) worldwide, which is one of the most important problems that reaches and links Human and Veterinary Medicine, as both share the use of a range of common ATM's, combined with the fact that antimicrobial resistant bacteria (ARB's) and antimicrobial resistance related genes (ARG's) can be transferred between animals, the environment and human beings, making this phenomenon a unique global health problem. The need for constant monitoring of the use of ATM is highlighted, in order to contain the emergence and/or expansion of resistant bacterial strains, as well as the integration between professionals in the mobilization of society as a whole in order to preserve the unique health. In this context, the objective was to carry out this literature review on some aspects of the use of antimicrobials in cattle, as well as the emergence of resistant bacterial strains and their impacts on public health.Item Identificação química e atividade antimicrobiana de óleos essenciais das folhas de Piper marginatum obtidos em meio ácido, básico e neutro(2019-12-18) Claudino, Líbna Larissa Monteiro; Ramos, Clécio Souza; http://lattes.cnpq.br/3782004073843685; http://lattes.cnpq.br/1342247970543261The increasing resistance of pathogenic microorganisms to conventional antimicrobials has been faced as a worldwide public health problem. The generalized use of antimicrobials in the treatment of infections caused by pathogens indulges microbial resistance, rendering them ineffective. The search for new plant compounds becomes an innovative alternative as an excellent source of new bioactive molecules. This work aims to define the chemical composition, as well as to evaluate the antimicrobial activity of essential oils of Piper marginatum leaves in basic, acid and neutral environments. The collection of plant material was made in the reserve dois irmãos located in the city of Recife on the campus of the Universidade Federal Rural de Pernambuco (UFRPE). The essential oils extracted from Piper marginatum leaves were obtained by hydrodistillation technique, using Clevenger type apparatus and the identification of their chemical constituents were determined by GC-MS. To obtain the oil in acidic environments an acidic solution of sulfuric acid: nitric acid in the molar ratio (1: 1) was prepared, as well as to obtain in basic environments a basic solution of potassium hydroxide was prepared at a concentration of 5 Mol.L-1. Antimicrobial activity was evaluated using the MIC method (Minimum Inhibitory Concentration). The results showed that the oil obtained in acid environments had a better activity against gram-negative E. coli bacteria with a MIC of 78.1 μg/ml and the fungi C. Albicans and C. Utilis with a MIC of 312 μg/ml and 78.1 μg/ml respectively. The activities of oils in basic and neutral environments were considered moderate to weak for all microorganisms tested, and showed MIC ranging from 625 μg/ml to 2500 μg/ml for both oils. Regarding the identification of the constituents, the major compounds found in the oils obtained in the basic and neutral environments were Macrocarpene, and Z Asarone, respectively. These results contribute to the chemical and biological knowledge of P. Marginatum, which is widely publicized as an excellent plant for therapeutic purposes.Item Investigação do potencial antibiofilme da lectina de folhas de Schinus terebinthifolia Raddi contra Staphylococcus aureus(2019-12-20) Silva, Talyta Naldeska da; Pontual, Emmanuel Viana; Silva, Pollyanna Michelle da; http://lattes.cnpq.br/0563176148137978; http://lattes.cnpq.br/1777060469196142; http://lattes.cnpq.br/8762925956752737Biofilms are complex microbial communities that have been associated with the incidence of infections, including in the hospital environment. Its formation is considered a determining factor for virulence in microorganisms and strongly contributes with the microbial resistance to conventional antimicrobials. In this sense, the search for natural compounds with antimicrobial activity that are more effective and less toxic to host cells. Plants are important sources of bioactive compounds, including lectins, a class of carbohydrate-binding proteins whose antimicrobial action has been reported. SteLL is a leaf lectin isolated from Schinus terebinthifolia Raddi (Anacardiaceae) with antimicrobial action that was previously reported. In this work, the antibacterial and antibiofilm potential of SteLL against sensitive (UFPEDA 02) and oxacillin resistant (UFPEDA 670) isolates of Staphylococcus aureus was evaluated. SteLL was a bacteriostatic and bactericidal agent against UFPEDA 02 and UFPEDA 670 isolates with MIC50 (Minimum Inhibitory Concentration) of 12.5 and 25.0 μg/mL and CMB (Minimum Bactericidal Concentration) of 50.0 and 100 μg/mL, respectively. The growth kinetics of the cells treated with SteLL revealed a dose-dependent growth inhibition regarding to control. SteLL caused morphometric alterations in S. aureus cells and inhibited biofilm formation of UFPEDA 02 at concentrations between 400 and 25.0 μg/mL and UFPEDA 670 between 400 and 100 μg/mL. In conclusion, SteLL is an antibacterial agent against Staphylococcus aureus by inhibiting the growth, promoting cell death and inhibiting bacterial biofilm formation.Item Análise da Influência do número de cópias na expressão do gene blaKPC(2021-03-05) Oliveira, Michelly Maria Pereira e; Almeida, Anna Carolina Soares; http://lattes.cnpq.br/4153747599532886Enterobacteria has stood out in clinical practice by detecting enzymatic mechanisms that confer resistance to antimicrobials, especially Klebsiella pneumoniae carbapenemase (KPC) due to its rapid worldwide dissemination caused by the location of the blaKPC gene in large transferable plasmids and transposons. The expression of the blaKPC gene can be affected by intrinsic characteristics of the host that hosts it or the number of copies. An unusual phenotype was observed in clinical isolates of P. stuartii and M. morganii and their respective transformants, where E. coli cells that received plasmids that carried the blaKPC gene, showed MIC values, for some beta- lactams, higher than in clinical isolates. The objective of this work was to analyze the number of copies of the blaKPC gene, relating them to their respective MICs. The genomic DNA of the bacterial isolates was extracted from the PromegaTM WizardTM Genomic DNA Purification kit according to the manufacturer's guidelines, and was then quantified by spectrophotometry using the NanoDropTM Lite equipment from Thermo Fisher Scientific. The endogenous control genes were chosen from the literature after a robust search, after which they were analyzed in silico. Using databases, software and other tools, primers were designed. To carry out absolute quantification, an estimate was made based on a proportion of the relative quantitative relationship between target and endogenous control, using the formula 2-ΔCq. For the experiments, the SteponeTM Real-time PCR System (Applied Biosystems) and the SYBR Green PCR Master Mix (Applied Biosystems) were used. The designed primers underwent a validation step to evaluate their efficiency (tufMm - 93,019, tufPs - 90,228 and tufKp - 103,474, both with R2 close to 1). The data generated by the absolute qPCR experiments were associated with the different phenotypic profiles observed and from the tests it was determined that the number of copies of the blaKPC gene for transforming isolates and clinical isolates does not vary significantly, pointing out that another mechanism must be interfering in the expression of the blaKPC gene, directly influencing resistance levels.Item Prospecção da atividade antimicrobiana de polissacarídeos extraídos das paredes celulares das leveduras Kluyveromyces marxianus, Kluyveromyces lactis e Saccharomyces cerevisiae(2021-02-26) Araújo, Isabelle Maria Feitosa de; Ferreira, Éder Galinari; http://lattes.cnpq.br/7670722046479986; http://lattes.cnpq.br/5044579569126838Polysaccharides from the most diverse sources, may have pharmacological activities such as, for example, antioxidant, immunomodulatory, anticoagulant and antimicrobial. Bearing in mind that this last activity has not yet been evaluated, according to our bibliographic survey, for the cell wall polysaccharides of the yeasts Kluyveromyces marxianus and Kluyveromyces lactis, the objective of this study was to verify the antimicrobial activity of polysaccharides extracted from the cell walls of the yeasts Kluyveromyces marxianus CCT7735 and Kluyveromyces lactis CBS2359 and compare them to a non-Kluyveromyes yeast like Saccharomyces cerevisiae CAT-1. The susceptibility tests were performed in Petri dishes (90 x 15 mm) using the Kirby-Bauer disc-diffusion method as recommended by the M 100 supplement of the 29th edition of the Clinical & Laboratory Standards Institute. Ten microliters of the polysaccharide solution (10 mg/mL) solubilized in distilled water and sterilized by filtration were deposited on sterile paper discs (6 mm). Polysaccharides were tested against Escherichia coli ATCC 25922 (positive control: 100/10 μg of piperacillin-tazobactam); Staphylococcus aureus ATCC 29213 (positive controls: 30 μg of cefoxitin and 10 units of penicillin); Pseudomonas aeruginosa ATCC 27853 (positive controls: 100/10 μg of piperacillin-tazobactam and 10 μg of gentamicin); Klebsiella pneumoniae ATCC 700603 (positive control: 10 μg gentamicin) and Enterococcus faecalis ATCC 29212 (positive controls: 30 μg tetracycline and 10 units of penicillin). None of the cell wall polysaccharide samples evaluated inhibited the growth of the pathogenic bacteria strains tested. Thus, at least in native molecules, polysaccharides did not show antimicrobial activity. We suggest that further studies be carried out with the samples evaluated, either for other pharmacological applications/activities or with the chemical modification or modification of the concentration of these polysaccharides, followed by a new test for antimicrobial activity, among others.Item Estudo químico e atividade antimicrobiana das folhas de Piper callosum e Piper corcovadensis (Piperaceae)(2019-02-22) Lima, Jéssica Bruna de; Ramos, Clécio Souza; http://lattes.cnpq.br/3782004073843685; http://lattes.cnpq.br/8759155622677149