RESUMO
Polymeric films containing pomegranate peel extract (PPE) can act as a drug-delivery platform for topical treatment of candidiasis. The composition, mechanical resistance, and in vitro antifungal activity of a polymeric film containing PPE at 1.25 mg.mL-1 were investigated. Films were prepared using a solvent casting technique. The incorporation of PPE in the polymeric matrix gave rise to homogeneous, smooth, shiny, and yellowish-brown films. FTIR spectra of the film containing PPE showed differences without compromising the stability of the extract and the matrix. SEM analysis showed the existence of interruptions in the continuity of the films with extract, which promoted a reduction in the mechanical parameters without significantly changing the tensile strength and elongation at break. Films showed adequate mechanical properties and antifungal activity against Candida albicans, C. glabrata, C. krusei and C. tropicalis.
Assuntos
Candidíase , Punica granatum , Antifúngicos/farmacologia , Candida albicans , Polímeros , Extratos Vegetais/farmacologia , Candidíase/tratamento farmacológicoRESUMO
Chronic wounds constitute a serious public health problem, and developing pharmaceutical dosage forms to ensure patient comfort and safety, as well as optimizing treatment effectiveness, are of great interest in the pharmaceutical, medical and biomaterial fields. In this work, the preparation of films based on blends of poly(vinyl alcohol), starch and poly(acrylic acid), polymers widely used as pharmaceutical excipients, and pomegranate peel extract (PPE), a bioactive compound with antimicrobial and healing activities relevant to the use as a bioactive wound dressing, was proposed. Initially, the minimum inhibitory concentration (MIC) of the PPE was investigated by an in vitro method. Then, the best concentration of the PPE to be used to prepare the films was researched using an antimicrobial susceptibility test with the disc diffusion method. The microbiological assay was performed in films prepared by the solvent casting method in the presence of two concentrations of PPE: 1.25% w/v and 2.5% w/v. Films containing the lower PPE concentration showed antimicrobial activity against Staphylococcus aureus and Staphylococcus epidermidis, with a difference that was not considered statistically significant when compared to the higher concentration of the extract. Therefore, the films prepared with the lower proportion of PPE (1.25% w/v) were considered for the other studies. The miscibility and stability of the extract in the films were investigated by thermal analysis. Parameters that determine the barrier properties of the films were also investigated by complementary techniques. Finally, in vitro biological tests were performed for safety evaluation and activity research. Analysis of the results showed that the incorporation of the higher proportion of starch in the blend (15% v/v) (PVA:S:PAA:PPE4) yielded smooth, transparent, and domain-free films without phase separation. Additionally, the PVA:S:PAA:PPE4 film presented barrier properties suitable for use as a cover. These films, when subjected to the in vitro hemolytic activity assay, were nonhemolytic and biocompatible. No toxicity from the extract was observed at the concentrations studied. The results of the wound healing in vitro test showed that films containing 1.25% PPE are efficient in reducing the scratch open area, provoking almost total closure of the scratches within 48 h without cytotoxicity.
Assuntos
Antibacterianos/química , Bandagens , Membranas Artificiais , Álcool de Polivinil/química , Punica granatum/química , Amido/química , Animais , Linhagem Celular , Camundongos , Staphylococcus aureus/crescimento & desenvolvimento , Staphylococcus epidermidis/crescimento & desenvolvimentoRESUMO
Although lifestyle and physiology in obese individuals are accepted to lead to changes in the intestinal microbiota, uncertainty remains about microbiota dysbiosis, and xenobiotics intake, as a source of selective pressure, independent of antimicrobial chemotherapy. The aim of this study was to compare the occurrence of antimicrobial resistance genetic markers (ARG) in faecal specimens of eutrophic, overweight and obese individuals, and their correlation with xenobiotic intake and gut bacteria density. Methods: This was a cross-sectional case-controlled study including 72 adult participants with no record of intestinal or systemic diseases, or recent use of antimicrobials, grouped as eutrophic, overweight, or obese. Anthropometric profile, eating habits and oral xenobiotics intake were recorded. Faecal metagenomic DNA was used to screen for ARG by PCR, and to measure bacterial groups by fluorescence in situ hybridization (FISH). Student's t and Wilcoxon tests were used to compare means and differences in ARG detection (95% confidence intervals). Correlation analyses (odds ratio) and relationships between bacteria density and ARG were determined. Results: Increase in abdominal circumference, waist circumference, hip, waist-hip ratio, BMI, carbohydrate, fibres, and total calorie intakes were different from eutrophic to obese participants. Habitual use of antihypertensive and anti-inflammatory drugs, antacids, and artificial sweeteners were associated mainly with obesity and overweight. Nutritional supplements were associated to the eutrophic group. ARG screening showed differences being more frequent among obese, and positive for 27 genetic markers related to ß-lactams, tetracyclines, the macrolide lincosamide and streptogramin group, quinolones, sulfonamides, aminoglycosides, and efflux pump. Positive correlation between ARG and BMI, caloric intake, and intake of xenobiotics, was observed for obese individuals. Relationships among ARG detection and bacteria densities were also different. Conclusions: This study reinforces the hypothesis that obese individuals may harbour an altered gut microbiota, if compared to eutrophic. The overweight individuals display a transitional gut microbiota which seems to be between eutrophic and obese. Furthermore, the increased xenobiotic intake associated to obesity may play an important role in the antimicrobial resistance phenomenon.
Assuntos
Resistência Microbiana a Medicamentos/genética , Trato Gastrointestinal/microbiologia , Sobrepeso/microbiologia , Adulto , Antiácidos/uso terapêutico , Anti-Inflamatórios não Esteroides/uso terapêutico , Anti-Hipertensivos/uso terapêutico , Suplementos Nutricionais , Fezes/microbiologia , Feminino , Microbioma Gastrointestinal/genética , Humanos , Hibridização in Situ Fluorescente , Masculino , Pessoa de Meia-Idade , Edulcorantes/administração & dosagem , Xenobióticos/administração & dosagem , Adulto JovemRESUMO
Anaerobic digestion figures as a sustainable alternative to avoid discharge of cattle manure in the environment, which results in biogas and biofertilizer. Persistence of potentially pathogenic and drug-resistant bacteria during anaerobic digestion of cattle manure was evaluated. Selective cultures were performed for enterobacteria (ENT), non-fermenting Gram-negative rods (NFR) and Gram-positive cocci (GPC). Antimicrobial susceptibility patterns were determined and a decay of all bacterial groups was observed after 60days. Multidrug-resistant bacteria were detected both the influent and effluent. GPC, the most prevalent group was highly resistant against penicillin and levofloxacin, whereas resistance to ampicillin, ampicillin-sulbactam and chloramphenicol was frequently observed in the ENT and NFR groups. The data point out the need of discussions to better address management of biodigesters and the implementation of sanitary and microbiological safe treatments of animal manures to avoid consequences to human, animal and environmental health.