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1.
Meat Sci ; 184: 108666, 2022 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-34653801

RESUMO

Forty-eight Churra ewes and their suckling lambs were assigned to four dietary treatments: control (CTRL), VIT-E (500 mg kg-1 TMR vitamin E), GP-5 (5% grape pomace) and GP-10 (10% grape pomace). After slaughter (11.5 kg live weight), longissimus muscle of lambs was sliced, packaged under modified atmosphere (80,20%/O 2:CO 2) and stored in retail conditions. At each sampling point (0, 3, 7, 10, 14 days), microbiological, physicochemical and sensory characteristics were analysed. Vitamin E and GP-5 were found to be effective (p < 0.05) at preventing enterobacteria growth as of day 10. After day 10, vitamin E and grape pomace in the ewe's supplementation reduced metmyoglobin (p < 0.05) lipid oxidation (p < 0.05) and sensory spoilage throughout the storage period. An effect of the grape pomace dosage was observed, with the supplementation at 5% being more effective. Therefore, we can conclude that grape pomace was just as effective as vitamin E in preventing spoilage during retail storage.


Assuntos
Dieta/veterinária , Armazenamento de Alimentos , Carne Vermelha/análise , Vitis , Ração Animal/análise , Animais , Enterobacteriaceae/crescimento & desenvolvimento , Feminino , Lactação/fisiologia , Masculino , Carne Vermelha/microbiologia , Carneiro Doméstico , Vitamina E/administração & dosagem
2.
Food Microbiol ; 99: 103834, 2021 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-34119118

RESUMO

The antioxidant and antimicrobial effect of sesame oil (10, 30, and 50 g/kg) and sesamol (0.1, 0.3, and 0.5 g/kg) in meatballs during cold storage for 18 days at 3 ± 1 °C was investigated. Sesame oil and sesamol did not alter the sensory attributes of meatballs. Addition of either sesame oil or sesamol significantly delayed lipid oxidation when compared with control. Sesamol exhibited more potent antioxidant activities more than sesame oil. During storage, the aerobic plate counts (APCs) and Enterobacteriaceae counts (EBCs) were markedly (P < 0.01) decreased in meatballs treated with sesame oil or sesamol in comparison with untreated control samples. Control meatballs showed signs of quality deterioration at day 7 of storage, while treated meatballs exhibited longer shelf lifes ranged from 9-18 days according to sesame oil or sesamol concentrations. Both sesame oil and sesamol induced marked (P < 0.01) decline in the counts of E. coli O157:H7, Salmonella enterica serovar Typhimurium, Staphylococcus aureus and Listeria monocytogenes that artificially inoculated to meatballs. Sesamol was more effective than sesame oil in the reduction of APCs, EBCs as well as foodborne pathogens. The results suggest that both sesame oil and sesamol are potentially useful natural additives to fresh meat products for improving its microbial quality and extending its shelf life during cold storage.


Assuntos
Antibacterianos/farmacologia , Antioxidantes/farmacologia , Benzodioxóis/farmacologia , Aditivos Alimentares/farmacologia , Produtos da Carne/análise , Fenóis/farmacologia , Óleo de Gergelim/farmacologia , Animais , Enterobacteriaceae/efeitos dos fármacos , Enterobacteriaceae/crescimento & desenvolvimento , Manipulação de Alimentos , Armazenamento de Alimentos , Listeria monocytogenes/efeitos dos fármacos , Listeria monocytogenes/crescimento & desenvolvimento , Produtos da Carne/microbiologia , Salmonella typhimurium/efeitos dos fármacos , Salmonella typhimurium/crescimento & desenvolvimento , Suínos
3.
Commun Biol ; 4(1): 331, 2021 03 12.
Artigo em Inglês | MEDLINE | ID: mdl-33712689

RESUMO

Multidrug-resistant (MDR) bacteria pose a grave concern to global health, which is perpetuated by a lack of new treatments and countermeasure platforms to combat outbreaks or antibiotic resistance. To address this, we have developed a Facile Accelerated Specific Therapeutic (FAST) platform that can develop effective peptide nucleic acid (PNA) therapies against MDR bacteria within a week. Our FAST platform uses a bioinformatics toolbox to design sequence-specific PNAs targeting non-traditional pathways/genes of bacteria, then performs in-situ synthesis, validation, and efficacy testing of selected PNAs. As a proof of concept, these PNAs were tested against five MDR clinical isolates: carbapenem-resistant Escherichia coli, extended-spectrum beta-lactamase Klebsiella pneumoniae, New Delhi Metallo-beta-lactamase-1 carrying Klebsiella pneumoniae, and MDR Salmonella enterica. PNAs showed significant growth inhibition for 82% of treatments, with nearly 18% of treatments leading to greater than 97% decrease. Further, these PNAs are capable of potentiating antibiotic activity in the clinical isolates despite presence of cognate resistance genes. Finally, the FAST platform offers a novel delivery approach to overcome limited transport of PNAs into mammalian cells by repurposing the bacterial Type III secretion system in conjunction with a kill switch that is effective at eliminating 99.6% of an intracellular Salmonella infection in human epithelial cells.


Assuntos
Antibacterianos/farmacologia , Biologia Computacional , Desenho de Fármacos , Farmacorresistência Bacteriana Múltipla , Infecções por Enterobacteriaceae/tratamento farmacológico , Enterobacteriaceae/efeitos dos fármacos , Oligonucleotídeos Antissenso/farmacologia , Ácidos Nucleicos Peptídicos/farmacologia , Células 3T3 , Animais , Farmacorresistência Bacteriana Múltipla/genética , Enterobacteriaceae/genética , Enterobacteriaceae/crescimento & desenvolvimento , Infecções por Enterobacteriaceae/microbiologia , Células HeLa , Humanos , Camundongos , Testes de Sensibilidade Microbiana , Viabilidade Microbiana/efeitos dos fármacos , Estudo de Prova de Conceito , Células RAW 264.7
4.
Cell Host Microbe ; 28(2): 273-284.e6, 2020 08 12.
Artigo em Inglês | MEDLINE | ID: mdl-32668218

RESUMO

The clinical spectra of irritable bowel syndrome (IBS) and inflammatory bowel disease (IBD) intersect to form a scantily defined overlap syndrome, termed pre-IBD. We show that increased Enterobacteriaceae and reduced Clostridia abundance distinguish the fecal microbiota of pre-IBD patients from IBS patients. A history of antibiotics in individuals consuming a high-fat diet was associated with the greatest risk for pre-IBD. Exposing mice to these risk factors resulted in conditions resembling pre-IBD and impaired mitochondrial bioenergetics in the colonic epithelium, which triggered dysbiosis. Restoring mitochondrial bioenergetics in the colonic epithelium with 5-amino salicylic acid, a PPAR-γ (peroxisome proliferator-activated receptor gamma) agonist that stimulates mitochondrial activity, ameliorated pre-IBD symptoms. As with patients, mice with pre-IBD exhibited notable expansions of Enterobacteriaceae that exacerbated low-grade mucosal inflammation, suggesting that remediating dysbiosis can alleviate inflammation. Thus, environmental risk factors cooperate to impair epithelial mitochondrial bioenergetics, thereby triggering microbiota disruptions that exacerbate inflammation and distinguish pre-IBD from IBS.


Assuntos
Antibacterianos/efeitos adversos , Dieta Hiperlipídica/efeitos adversos , Disbiose/patologia , Metabolismo Energético/fisiologia , Doenças Inflamatórias Intestinais/microbiologia , Síndrome do Intestino Irritável/microbiologia , Animais , Anti-Inflamatórios não Esteroides/uso terapêutico , Disbiose/induzido quimicamente , Enterobacteriaceae/crescimento & desenvolvimento , Microbioma Gastrointestinal , Humanos , Mucosa Intestinal/microbiologia , Mucosa Intestinal/patologia , Complexo Antígeno L1 Leucocitário/metabolismo , Mesalamina/uso terapêutico , Camundongos , Camundongos Endogâmicos C57BL , Mitocôndrias/metabolismo , PPAR gama/agonistas
5.
J Anim Sci ; 98(6)2020 Jun 01.
Artigo em Inglês | MEDLINE | ID: mdl-32497185

RESUMO

The outer cell wall of yeast is characterized by high levels of ß-glucans and mannan-oligosaccharides (MOS), which have been linked with beneficial effects on intestinal health and immune status in dogs. In this study, a standardized in vitro simulation of the canine gastrointestinal tract (Simulator of the Canine Intestinal Microbial Ecosystem; SCIME) was used to evaluate the effect of a Saccharomyces cerevisiae-based product, consisting of 27.5% ß-glucans and 22.5% MOS, on the activity (as assessed by measurement of fermentative metabolites) and composition (as assessed by 16S-targeted Illumina sequencing) of canine intestinal microbiota. The S. cerevisiae-based product was tested at three different dosages, i.e., 0.5, 1.0, and 2.0 g/d. A dose-dependent fermentation pattern was observed along the entire length of the colon, as shown by the increased production of the health-related acetate, propionate, and butyrate for the three concentrations tested (0.5, 1.0, and 2.0 g/d). A consistent finding for all three tested concentrations was the increased propionate production (P < 0.05) in the simulated proximal and distal colon. These changes in terms of fermentative metabolites could be linked to specific microbial alterations at the family level, such as the specific stimulation of the propionate-producing families Porphyromonadaceae and Prevotellaceae upon in vitro exposure to the S. cerevisiae-based product. Other consistent changes in community composition upon repeated exposure included the decrease in the Enterobacteriaceae and the Fusobacteriaceae families, which both contain several potentially opportunistic pathogens. Altogether, the generated data support a possible health-promoting role of a product high in ß-glucans and MOS when supplemented to the dogs' diet.


Assuntos
Suplementos Nutricionais/análise , Cães/fisiologia , Microbioma Gastrointestinal/efeitos dos fármacos , Mananas/farmacologia , Oligossacarídeos/farmacologia , Saccharomyces cerevisiae/química , beta-Glucanas/farmacologia , Animais , Parede Celular/química , Dieta/veterinária , Cães/microbiologia , Enterobacteriaceae/efeitos dos fármacos , Enterobacteriaceae/crescimento & desenvolvimento , Fermentação , Fusobactérias/efeitos dos fármacos , Fusobactérias/crescimento & desenvolvimento , Trato Gastrointestinal/metabolismo , Trato Gastrointestinal/microbiologia , Fermento Seco/química
6.
PLoS One ; 14(11): e0224836, 2019.
Artigo em Inglês | MEDLINE | ID: mdl-31714906

RESUMO

The opportunistic pathogen Escherichia coli, a common member of the human gut microbiota belonging to the Enterobacteriaceae family, is the causative agent of the majority of urinary tract infections (UTIs). The gut microbiota serves as a reservoir for uropathogenic E. coli where they are shed in feces, colonize the periurethral area, and infect the urinary tract. Currently, front line treatment for UTIs consists of oral antibiotics, but the rise of antibiotic resistance is leading to higher rates of recurrence, and antibiotics cause collateral damage to other members of the gut microbiota. It is commonly believed that incorporation of the American cranberry, Vaccinium macrocarpon, into the diet is useful for reducing recurrence of UTIs. We hypothesized such a benefit might be explained by a prebiotic or antimicrobial effect on the gut microbiota. As such, we tested cranberry extracts and whole cranberry powder on a human gut microbiome-derived community in a gut simulator and found that cranberry components broadly modulate the microbiota by reducing the abundance of Enterobacteriaceae and increasing the abundance of Bacteroidaceae. To identify the specific compounds responsible for this, we tested a panel of compounds isolated from cranberries for activity against E. coli, and found that salicylate exhibited antimicrobial activity against both laboratory E. coli and human UTI E. coli isolates. In a gut simulator, salicylate reduced levels of Enterobacteriaceae and elevated Bacteroidaceae in a dose dependent manner.


Assuntos
Bacteroidaceae/crescimento & desenvolvimento , Enterobacteriaceae/crescimento & desenvolvimento , Microbioma Gastrointestinal , Modelos Biológicos , Extratos Vegetais/farmacologia , Vaccinium macrocarpon/química , Bacteroidaceae/efeitos dos fármacos , Enterobacteriaceae/efeitos dos fármacos , Escherichia coli/efeitos dos fármacos , Escherichia coli/isolamento & purificação , Microbioma Gastrointestinal/efeitos dos fármacos , Humanos , Hidroxibenzoatos/farmacologia , Testes de Sensibilidade Microbiana , Pós , Ácido Salicílico/farmacologia , Infecções Urinárias/microbiologia
7.
Artigo em Inglês | MEDLINE | ID: mdl-31358592

RESUMO

In this article, we report a case series of patients with infections caused by Enterobacteriales coresistant to carbapenems and polymyxins who were treated with ceftazidime/avibactam (CAZ-AVI) salvage therapy on a compassionate-use protocol. We enrolled 29 adult patients in 3 centers that had an infection due to a resistant microorganism and for whom the treatments available were considered ineffective, treated them with CAZ-AVI, and assessed clinical and microbiological cure at the end of treatment and all-cause mortality at 14 days and 30 days. The antimicrobial susceptibility profile was determined using broth microdilution, and total genomic DNA was sequenced. Twelve (41.4%) patients had bacteremia, and 48.3% (14/29) of the infections were treated with combination therapy. All strains were producers of KPC-2 and were susceptible to CAZ-AVI (MIC90, 1 µg/ml). Clinical success was high (24/29 [82.7%; 95% confidence interval, 64.2 to 94.2%]), even for the bacteremic cases (75%). The 14-day and 30-day mortality rates were 9/29 (31%) and 15/29 (51.7%), respectively. The 14-day mortality rate for pneumonia was the same as that for bloodstream infections (33.3%) and although not significant, we found that patients with renal impairment that received adjusted doses of CAZ-AVI had high mortality (4/9 [44%]; P = 0.22). We concluded that CAZ-AVI is an option for the treatment of severe infections due to difficult-to-treat drug-resistant Enterobacteriales.


Assuntos
Antibacterianos/uso terapêutico , Compostos Azabicíclicos/uso terapêutico , Bacteriemia/tratamento farmacológico , Ceftazidima/uso terapêutico , Farmacorresistência Bacteriana Múltipla/efeitos dos fármacos , Infecções por Enterobacteriaceae/tratamento farmacológico , Pneumonia Bacteriana/tratamento farmacológico , Terapia de Salvação/métodos , Adulto , Bacteriemia/microbiologia , Bacteriemia/mortalidade , Bacteriemia/patologia , Carbapenêmicos/uso terapêutico , Combinação de Medicamentos , Farmacorresistência Bacteriana Múltipla/genética , Enterobacteriaceae/efeitos dos fármacos , Enterobacteriaceae/enzimologia , Enterobacteriaceae/crescimento & desenvolvimento , Enterobacteriaceae/patogenicidade , Infecções por Enterobacteriaceae/microbiologia , Infecções por Enterobacteriaceae/mortalidade , Infecções por Enterobacteriaceae/patologia , Feminino , Expressão Gênica , Humanos , Masculino , Testes de Sensibilidade Microbiana , Pessoa de Meia-Idade , Pneumonia Bacteriana/microbiologia , Pneumonia Bacteriana/mortalidade , Pneumonia Bacteriana/patologia , Polimixinas/uso terapêutico , Estudos Prospectivos , Análise de Sobrevida , beta-Lactamases/genética , beta-Lactamases/metabolismo
8.
PLoS One ; 14(2): e0211888, 2019.
Artigo em Inglês | MEDLINE | ID: mdl-30735536

RESUMO

BACKGROUND: Empiric antibiotic therapy for suspected hematogenous vertebral osteomyelitis (HVO) should be initiated immediately in seriously ill patients and may be required in those with negative microbiological results. The aim of this study was to inform the appropriate selection of empiric antibiotic regimens for the treatment of suspected HVO by analyzing antimicrobial susceptibility of isolated bacteria from microbiologically proven HVO. METHOD: We conducted a retrospective chart review of adult patients with microbiologically proven HVO in five tertiary-care hospitals over a 7-year period. The appropriateness of empiric antibiotic regimens was assessed based on the antibiotic susceptibility profiles of isolated bacteria. RESULTS: In total, 358 cases of microbiologically proven HVO were identified. The main causative pathogens identified were methicillin-susceptible Staphylococcus aureus (33.5%), followed by methicillin-resistant S. aureus (MRSA) (24.9%), Enterobacteriaceae (19.3%), and Streptococcus species (11.7%). Extended spectrum ß-lactamase (ESBL)-producing Enterobacteriaceae and anaerobes accounted for only 1.7% and 1.4%, respectively, of the causative pathogens. Overall, 73.5% of isolated pathogens were susceptible to levofloxacin plus rifampicin, 71.2% to levofloxacin plus clindamycin, and 64.5% to amoxicillin-clavulanate plus ciprofloxacin. The susceptibility to these oral combinations was lower in cases of healthcare-associated HVO (52.6%, 49.6%, and 37.6%, respectively) than in cases of community-acquired HVO (85.8%, 84.0%, and 80.4%, respectively). Vancomycin combined with ciprofloxacin, ceftriaxone, ceftazidime, or cefepime was similarly appropriate (susceptibility rates of 93.0%, 94.1%, 95.8%, and 95.8%, respectively). CONCLUSIONS: Based on our susceptibility data, vancomycin combined with a broad-spectrum cephalosporin or fluoroquinolone may be appropriate for empiric treatment of HVO. Fluoroquinolone-based oral combinations may be not appropriate due to frequent resistance to these agents, especially in cases of healthcare-associated HVO.


Assuntos
Antibacterianos/uso terapêutico , Infecções Bacterianas/tratamento farmacológico , Enterobacteriaceae/efeitos dos fármacos , Staphylococcus aureus Resistente à Meticilina/efeitos dos fármacos , Osteomielite/tratamento farmacológico , Streptococcus/efeitos dos fármacos , Idoso , Combinação Amoxicilina e Clavulanato de Potássio/uso terapêutico , Infecções Bacterianas/diagnóstico , Infecções Bacterianas/microbiologia , Infecções Bacterianas/patologia , Ciprofloxacina/uso terapêutico , Clindamicina/uso terapêutico , Quimioterapia Combinada , Pesquisa Empírica , Enterobacteriaceae/crescimento & desenvolvimento , Enterobacteriaceae/patogenicidade , Feminino , Expressão Gênica , Humanos , Levofloxacino/uso terapêutico , Masculino , Staphylococcus aureus Resistente à Meticilina/crescimento & desenvolvimento , Staphylococcus aureus Resistente à Meticilina/patogenicidade , Testes de Sensibilidade Microbiana , Pessoa de Meia-Idade , Osteomielite/diagnóstico , Osteomielite/microbiologia , Osteomielite/patologia , Estudos Retrospectivos , Rifampina/uso terapêutico , Coluna Vertebral/efeitos dos fármacos , Coluna Vertebral/microbiologia , Coluna Vertebral/patologia , Streptococcus/crescimento & desenvolvimento , Streptococcus/patogenicidade , Vancomicina/uso terapêutico , beta-Lactamases/genética , beta-Lactamases/metabolismo
9.
BMC Infect Dis ; 18(1): 590, 2018 Nov 20.
Artigo em Inglês | MEDLINE | ID: mdl-30458721

RESUMO

BACKGROUND: Men with urinary retention secondary to benign prostatic hyperplasia (BPH) are prone to genitourinary infections. Physicians should be aware of the current antimicrobial susceptibility pattern in this population if empirical treatment is needed. The goal of this study was to evaluate variations in prevalence, composition and antimicrobial susceptibility of bacterial flora in men with indwelling catheters subjected to surgery for BPH in chosen time periods since 1994. Necessary changes in empirical therapy were also assessed. METHODS: All patients with indwelling catheters admitted to a single urological center for BPH surgery in the years 1994-1996, 2004-2006, and 2011-2015 were considered. Catheterization times and results of urine cultures from samples collected at admission were evaluated. Susceptibility for selected antimicrobials was compared separately for Gram negative and Gram positive species. For each agent and for their combinations effectiveness of empirical therapy was calculated dividing the number of patients with bacteriuria susceptible to the agents by the total number of patients with bacteriuria. RESULTS: Bacteriuria was present in 70% of 169, 72% of 132, and 69% of 156 men in the respective time periods. The incidence of Gram-positive strains increased from 10 to 37% (P < 0.001). Their susceptibility to amoxicillin/clavulanate was fluctuating (81, 61, 77%; P=NS). No vancomycin-resistant strain was present. Gram-negative flora composition was stable. Their susceptibility decreased to ciprofloxacin (70 to 53%; P = 0.01) and amoxicillin/clavulanate (56 to 37%; P < 0.01) while it increased to gentamycin (64 to 88%; P < 0.001) and co-trimoxazole (14 to 62%; P < 0.001); susceptibility to amikacin remained high (> 85%). Only two cases of resistance to carbapenems in 2004-2006 were found. In vitro effectiveness of amikacin + amoxicillin/clavulanate in empirical therapy was slowly decreasing (87 to 77%; P=NS). Imipenem was found the most effective single agent (90-95%) and its efficacy was even improved by adding vancomycin (97-98%). CONCLUSIONS: Substantial rise in the incidence of Gram-positive species and fluctuations in antimicrobial susceptibility patterns were found. Empirical therapy of genitourinary infection in catheterized men with BPH should now involve antimicrobial agents effective both to Enterococci and Enterobacteriaceae. Periodic monitoring and publishing data on antimicrobial susceptibility for this population is necessary.


Assuntos
Anti-Infecciosos/uso terapêutico , Infecções Relacionadas a Cateter/epidemiologia , Infecções Relacionadas a Cateter/microbiologia , Farmacorresistência Bacteriana , Hiperplasia Prostática/microbiologia , Cateteres Urinários/microbiologia , Anti-Infecciosos/classificação , Bacteriúria/epidemiologia , Bacteriúria/microbiologia , Infecções Relacionadas a Cateter/complicações , Infecções Relacionadas a Cateter/tratamento farmacológico , Cateterismo/efeitos adversos , Cateterismo/estatística & dados numéricos , Farmacorresistência Bacteriana/efeitos dos fármacos , Enterobacteriaceae/classificação , Enterobacteriaceae/efeitos dos fármacos , Enterobacteriaceae/crescimento & desenvolvimento , Enterobacteriaceae/isolamento & purificação , Humanos , Masculino , Testes de Sensibilidade Microbiana , Prevalência , Hiperplasia Prostática/complicações , Hiperplasia Prostática/epidemiologia , Hiperplasia Prostática/terapia , Estudos Retrospectivos , Cateteres Urinários/efeitos adversos , Retenção Urinária/complicações , Retenção Urinária/epidemiologia , Retenção Urinária/microbiologia , Retenção Urinária/terapia
10.
PLoS One ; 13(10): e0205711, 2018.
Artigo em Inglês | MEDLINE | ID: mdl-30312341

RESUMO

Potato blackleg and soft rot caused by Pectobacterium and Dickeya species are among the most significant bacterial diseases affecting potato production globally. In this study we estimate the impact of future temperatures on establishment of non-indigenous but confirmed Pectobacterium and Dickeya species in Great Britain (GB). The calculations are based on probabilistic climate change data and a model fitted to disease severity data from a controlled environment tuber assay with the dominant potato blackleg and soft rot-causing species in GB (P. atrosepticum), and three of the main causative agents in Europe (P. carotovorum subsp. brasiliense, P. parmentieri, Dickeya solani). Our aim was to investigate if the European strains could become stronger competitors in the GB potato ecosystem as the climate warms, on the basis of their aggressiveness in tubers at different temperatures. Principally, we found that the tissue macerating capacity of all four pathogens will increase in GB under all emissions scenarios. The predominant Pectobacterium and Dickeya species in Europe are able to cause disease in tubers under field conditions currently seen in GB but are not expected to become widely established in the future, at least on the basis of their aggressiveness in tubers relative to P. atrosepticum under GB conditions. Our key take-home messages are that the GB potato industry is well positioned to continue to thrive via current best management practices and continued reinforcement of existing legislation.


Assuntos
Mudança Climática , Enterobacteriaceae , Pectobacterium , Doenças das Plantas/microbiologia , Tubérculos/microbiologia , Solanum tuberosum/microbiologia , Enterobacteriaceae/crescimento & desenvolvimento , Pectobacterium/crescimento & desenvolvimento , Doenças das Plantas/etiologia , Temperatura , Reino Unido
11.
Food Res Int ; 111: 524-533, 2018 09.
Artigo em Inglês | MEDLINE | ID: mdl-30007715

RESUMO

The use of antioxidants and refrigeration storage in modified atmosphere packaging, MAP, are the main strategies to slow down the oxidative and microbial deterioration of fresh meat. Synthetic antioxidants are commonly used for this purpose, however due to their controversial health effects, natural alternatives for their replacement are being looked for. The main aim of this work is the evaluation of pressurised aqueous extracts from oak wood as natural preservative of pork patties. The effect of different amounts of oak wood extracts (0.05, 0.5 and 1.0%) on the self-life of pork patties packed in MAP in refrigeration during 12 days were studied in comparison with the use of sodium ascorbate as synthetic preservative. Samples treated with oak wood extracts showed lower lipid oxidation, higher antioxidant capacity and an inhibitory effect on the enterobacteria growth. Furthermore, the addition of oak wood extracts resulted in a dramatically decrease of the volatile compounds coming from the lipid oxidation reactions. On the other hand, it is noteworthy that the use of oak wood extracts modified sensorial characteristics. Intensity colour was higher and new sensorial features such as oak wood and sweet spices appeared which were well appreciated.


Assuntos
Antioxidantes/farmacologia , Embalagem de Alimentos , Produtos da Carne , Extratos Vegetais/farmacologia , Quercus/química , Madeira/química , Adulto , Animais , Fenômenos Químicos , Cor , Enterobacteriaceae/efeitos dos fármacos , Enterobacteriaceae/crescimento & desenvolvimento , Feminino , Contaminação de Alimentos , Microbiologia de Alimentos , Qualidade dos Alimentos , Armazenamento de Alimentos , Humanos , Metabolismo dos Lipídeos/efeitos dos fármacos , Produtos da Carne/microbiologia , Pessoa de Meia-Idade , Oxirredução , Carne Vermelha/microbiologia , Refrigeração , Suínos , Paladar , Substâncias Reativas com Ácido Tiobarbitúrico , Compostos Orgânicos Voláteis/análise , Adulto Jovem
12.
Lett Appl Microbiol ; 67(2): 175-182, 2018 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-29763981

RESUMO

Multidrug-resistant bacteria have become common all over the world, necessitating the development of new therapeutic strategies. Synergistic interactions between conventional antibiotics and natural bioactive may have therapeutic benefits in a clinical setting. There are plenty of medicinal plants that have proven efficacy against broad spectrum of micro-organisms. The aim of the work was to assess the antibacterial activity of Cladanthus arabicus, a Moroccan medicinal plant, and Bubonium imbricatum, a Moroccan endemic plant. The evaluation of the synergistic effect of extracted essential oils (EOs) together with some conventional antibiotics was also investigated. Checkerboard test was used to evaluate the interaction of EOs in combination with amoxicillin and neomycin. The results showed that EOs contain a potent activity against the tested Enterobacteriaceae isolates, with inhibition zones values in the range of 8·05 ± 0·1 and 13·1 ± 0·11 mm and MIC values between 200 µg ml-1 to 800 µg ml-1 for C. arabicus and from 400 µg ml-1 to 1600 µg ml-1 for B. imbricatum, respectively. Moreover, the current study allowed concluding that both EOs showed not only satisfactory antibacterial properties but also active effects combined with conventional antibiotics demonstrated by the Fractional Inhibitory Concentration Index (FICI). These findings are very interesting since there are no previous studies on synergistic interactions of these two plants with antibiotics. SIGNIFICANCE AND IMPACT OF THE STUDY: The development of antibiotic resistance is multifactorial, including the specific nature of the relationship of bacteria to antibiotics. This situation has forced scientists to search for new antimicrobial substances from various sources as novel antimicrobial chemotherapeutic agents. Recently, medicinal plants and their derivatives (essential oils, extracts) have become very important in therapeutics because they encounter minimal challenges of the emergence of resistance. In this direction, the antimicrobial activity of the endemic Bubonium imbricatum plant and medicinal Cladanthus arabicus plant essential oils against multidrug-resistant Enterobacteriaceae strains was demonstrated.


Assuntos
Amoxicilina/farmacologia , Antibacterianos/farmacologia , Asteraceae/química , Enterobacteriaceae/crescimento & desenvolvimento , Neomicina/farmacologia , Óleos Voláteis/farmacologia , Óleos de Plantas/farmacologia , Combinação de Medicamentos , Farmacorresistência Bacteriana Múltipla , Sinergismo Farmacológico , Enterobacteriaceae/efeitos dos fármacos , Humanos , Testes de Sensibilidade Microbiana
13.
Biol Pharm Bull ; 41(2): 208-212, 2018.
Artigo em Inglês | MEDLINE | ID: mdl-29386480

RESUMO

Mume fruit, the Japanese apricot (Prunus mume SIEB. et ZUCC.), is popular in Japan and is mostly consumed in the pickled form called umeboshi. This fruit is known to have anti-microbial properties, but the principal constituents responsible for the antimicrobial properties have not yet been elucidated. We investigated the antimicrobial activities of the phenolic compounds in P. mume against enterobacteria. In this study, growth inhibitory activities were measured as an index of the antibacterial activities. The phenolic compounds were prepared from a byproduct of umeboshi called umesu or umezu (often translated as "mume vinegar"). Umesu or umezu phenolics (UP) contain approximately 20% phenolic compounds with p-coumaric acid as a standard and do not contain citric acid. We observed the inhibitory effects of UP against the growth of some enterobacteria, at a relatively high concentration (1250-5000 µg/mL). Alkali hydrolysates of UP (AHUP) exhibited similar antibacterial activities, but at much lower concentrations of 37.5-300 µg/mL. Since AHUP comprises hydroxycinnamic acids such as caffeic acid, p-coumaric acid, and ferulic acid, the antibacterial activities of each of these acids were examined. Our study shows that the phenolic compounds in P. mume other than citric acid contribute to its antimicrobial activity against enterobacteria in the digestive tract.


Assuntos
Antibacterianos/farmacologia , Descoberta de Drogas , Enterobacteriaceae/efeitos dos fármacos , Alimentos em Conserva/análise , Frutas/química , Fenóis/farmacologia , Prunus/química , Antibacterianos/química , Antibacterianos/isolamento & purificação , Cromatografia Líquida de Alta Pressão , Ácidos Cumáricos/química , Ácidos Cumáricos/isolamento & purificação , Ácidos Cumáricos/farmacologia , Enterobacteriaceae/crescimento & desenvolvimento , Etnofarmacologia , Indústria de Processamento de Alimentos/economia , Liofilização , Hidrólise/efeitos dos fármacos , Indicadores e Reagentes/química , Resíduos Industriais/análise , Resíduos Industriais/economia , Japão , Medicina Tradicional do Leste Asiático , Testes de Sensibilidade Microbiana , Estrutura Molecular , Fenóis/química , Fenóis/isolamento & purificação , Hidróxido de Sódio/química
14.
Water Res ; 134: 292-300, 2018 05 01.
Artigo em Inglês | MEDLINE | ID: mdl-29433079

RESUMO

This study achieves a better operational simplicity for the phycoremediation of reverse osmosis (RO) concentrate using Scenedesmus quadricauda microalgae. Under continuous illumination with CO2 supplementation, algal growth in the RO concentrate resulted in a conversion of polymeric organic matter (a mixture of humic substances and polysaccharides) to biodegradable fractions and their prompt removal along with inorganic nutrients (NO3- and PO43-). The algal-induced degradation of humic-like substances which are typically refractory to microbial decomposition was demonstrated in an indirect manner. In this study, we also investigated the effects of algal treatment on the growth of Escherichia coli and removal of trace organic compounds (TOrCs) from the RO concentrate. Our results indicate that algal treatment of the RO concentrate using aeration with 10% (v/v) CO2 under continuous illumination is highly feasible as a safe and inexpensive technology to remove non- or slowly-biodegradable organic matter, reduce enteric bacteria, and attenuate TOrCs in wastewater. However, the results should not be generalized, but critically discussed, due to limitations of using the synthetic RO concentrate in evaluating the performance of wastewater remediation with microalgae.


Assuntos
Microalgas/crescimento & desenvolvimento , Osmose , Scenedesmus/crescimento & desenvolvimento , Eliminação de Resíduos Líquidos/métodos , Enterobacteriaceae/crescimento & desenvolvimento , Escherichia coli/crescimento & desenvolvimento , Filtração , Substâncias Húmicas , Nitratos , Compostos Orgânicos , Fosfatos , Polissacarídeos , Águas Residuárias , Poluentes da Água
15.
Nat Microbiol ; 3(2): 132-140, 2018 02.
Artigo em Inglês | MEDLINE | ID: mdl-29358683

RESUMO

The development of innovative high-throughput genomics and metabolomics technologies has considerably expanded our understanding of the commensal microorganisms residing within the human body, collectively termed the microbiota. In recent years, the microbiota has been reported to have important roles in multiple aspects of human health, pathology and host-pathogen interactions. One function of commensals that has attracted particular interest is their role in protection against pathogens and pathobionts, a concept known as colonization resistance. However, pathogens are also able to sense and exploit the microbiota during infection. Therefore, obtaining a holistic understanding of colonization resistance mechanisms is essential for the development of microbiome-based and microbiome-targeting therapies for humans and animals. Achieving this is dependent on utilizing physiologically relevant animal models. In this Perspective, we discuss the colonization resistance functions of the gut microbiota and sieve through the advantages and limitations of murine models commonly used to study such mechanisms within the context of enteric bacterial infection.


Assuntos
Microbioma Gastrointestinal/fisiologia , Trato Gastrointestinal/microbiologia , Interações Hospedeiro-Patógeno/fisiologia , Animais , Antibacterianos/uso terapêutico , Enterobacteriaceae/crescimento & desenvolvimento , Enterobacteriaceae/patogenicidade , Infecções por Enterobacteriaceae/tratamento farmacológico , Infecções por Enterobacteriaceae/microbiologia , Vida Livre de Germes , Interações Hospedeiro-Patógeno/efeitos dos fármacos , Humanos , Camundongos , Modelos Animais , Simbiose
16.
Plant Dis ; 102(3): 619-627, 2018 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-30673477

RESUMO

Colonization of Solanum dulcamara (bittersweet nightshade) plants by a GFP-tagged Dickeya solani type strain IPO2222 (IPO2254) was investigated by selective plating and epifluorescence stereomicroscopy (ESM), using in vitro plants and plants grown in compost soil. Replicated experiments were carried out in a growth chamber and the progress of infection and disease symptoms on tissue of the cultured plants, following leaf- and stem-base inoculations with bacteria, was evaluated. Microscopy observations were confirmed by spread-plating dilutions of plant extracts onto agar medium directly after the harvest. In experiments where the stem base of in vitro plants inoculated with a range of inocula of D. solani (104 to 108 colony forming units [cfu] ml-1) was examined at 14 days post infection (dpi), blackleg-like symptoms developed in more than 80% plants together with a reduction of the plant fitness (disease symptoms, weight, height, and appearance). In leaf-inoculated plants at 14 dpi, 15% of the plants exhibited severe blackleg-like symptoms. In detached S. dulcamara leaf assays, IPO2254 survived on the adaxial surface for 14 days at populations of 106 cfu per leaf. Thirty days after stem inoculation of plants grown in compost soil in pots, up to 104 cfu g-1 of GFP-tagged D. solani were found inside the stems. D. solani were detected inside the vascular tissue (xylem vessels) of stems, in the pith tissue in roots, and on the internal surface of the stem hollow. The implications of S. dulcamara infection by D. solani for the long-distance dispersal of the bacterial inoculum are discussed.


Assuntos
Enterobacteriaceae/fisiologia , Doenças das Plantas/microbiologia , Solanum/microbiologia , Enterobacteriaceae/crescimento & desenvolvimento , Proteínas de Fluorescência Verde , Folhas de Planta/microbiologia , Raízes de Plantas/microbiologia , Xilema/microbiologia
17.
Arh Hig Rada Toksikol ; 68(2): 116-126, 2017 Jun 27.
Artigo em Inglês | MEDLINE | ID: mdl-28665797

RESUMO

This study was conducted to determine the bacterial colonization of some bacterial groups, including extended-spectrum ß-lactamase (ESBLs) producers and methicillin-resistant Staphylococcus aureus (MRSA), on surfaces of the equipment and instruments in patient rooms and other workspaces in three different medical wards. The number of microorganisms on swabs was determined with the colony count method on selective microbiological mediums. The aerobic mesophylic microorganisms were found in 73.5 % out of 102 samples, with the average and maximum values of 2.6 × 102 and 4.6 × 103 colony forming units (CFU) 100 cm-2, respectively. Members of the family Enterobacteriaceae, coagulase positive staphylococci, coagulase-negative staphylococci, and enterococci were detected in 23.4, 31.4, 53.2, and 2.9 % of samples, respectively. The differences in bacterial counts on the surfaces of the psychiatric, oncology, and paediatric wards were statistically significant (P<0.001). About 40 % out of 19 isolates from the family Enterobacteriaceae showed multiple resistance to three or more different groups of tested antibiotics, while ESBL was confirmed for only one strain. Staphylococci isolates were mostly resistant to penicillin. MRSA was confirmed in 5.2 % of the tested S. aureus isolates. Greater attention should be paid to cleaning and the appropriate choice of disinfectants, especially in the psychiatric ward. Employees should be informed about the prevention of the spreading of nosocomial infections. Routine application of rapid methods for hygiene control of surfaces is highly recommended.


Assuntos
Antibacterianos/uso terapêutico , Infecção Hospitalar/prevenção & controle , Enterobacteriaceae/crescimento & desenvolvimento , Contaminação de Equipamentos , Staphylococcus aureus Resistente à Meticilina/crescimento & desenvolvimento , Quartos de Pacientes , Staphylococcus aureus/crescimento & desenvolvimento , Contagem de Colônia Microbiana , Humanos , Testes de Sensibilidade Microbiana
18.
Genomics ; 109(5-6): 374-382, 2017 10.
Artigo em Inglês | MEDLINE | ID: mdl-28625866

RESUMO

Franconibacter pulveris strain DJ34, isolated from Duliajan oil fields, Assam, was characterized in terms of its taxonomic, metabolic and genomic properties. The bacterium showed utilization of diverse petroleum hydrocarbons and electron acceptors, metal resistance, and biosurfactant production. The genome (4,856,096bp) of this strain contained different genes related to the degradation of various petroleum hydrocarbons, metal transport and resistance, dissimilatory nitrate, nitrite and sulfite reduction, chemotaxy, biosurfactant synthesis, etc. Genomic comparison with other Franconibacter spp. revealed higher abundance of genes for cell motility, lipid transport and metabolism, transcription and translation in DJ34 genome. Detailed COG analysis provides deeper insights into the genomic potential of this organism for degradation and survival in oil-contaminated complex habitat. This is the first report on ecophysiology and genomic inventory of Franconibacter sp. inhabiting crude oil rich environment, which might be useful for designing the strategy for bioremediation of oil contaminated environment.


Assuntos
Enterobacteriaceae/crescimento & desenvolvimento , Genoma Bacteriano , Hidrocarbonetos/metabolismo , Petróleo/microbiologia , Composição de Bases , Biodegradação Ambiental , Enterobacteriaceae/classificação , Enterobacteriaceae/genética , Enterobacteriaceae/isolamento & purificação , Tamanho do Genoma , Filogenia , Análise de Sequência de DNA
19.
Br J Nutr ; 117(7): 964-978, 2017 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-28460652

RESUMO

The aim of this study was to characterise the gut microbiota composition of piglets fed bovine colostrum (BC), milk replacer (MR) or sow milk (SM) in the post-weaning period. Piglets (n 36), 23-d old, were randomly allocated to the three diets. Faecal samples were collected at 23, 25, 27 and 30 d of age. Digesta from the stomach, ileum, caecum and mid-colon was collected at 30 d of age. Bacterial DNA from all samples was subjected to amplicon sequencing of the 16S rRNA gene. Bacterial enumerations by culture and SCFA analysis were conducted as well. BC-piglets had the highest abundance of Lactococcus in the stomach (P<0·0001) and ileal (P<0·0001) digesta, whereas SM-piglets had the highest abundance of Lactobacillus in the stomach digesta (P<0·0001). MR-piglets had a high abundance of Enterobacteriaceae in the ileal digesta (P<0·0001) and a higher number of haemolytic bacteria in ileal (P=0·0002) and mid-colon (P=0·001) digesta than SM-piglets. BC-piglets showed the highest colonic concentration of iso-butyric and iso-valeric acid (P=0·02). Sequencing and culture showed that MR-piglets were colonised by a higher number of Enterobacteriaceae, whereas the gut microbiota of BC-piglets was characterised by a change in lactic acid bacteria genera when compared with SM-piglets. We conclude that especially the ileal microbiota of BC-piglets had a closer resemblance to that of SM-piglets in regard to the abundance of potential enteric pathogens than did MR-piglets. The results indicate that BC may be a useful substitute for regular milk replacers, and as a feeding supplement in the immediate post-weaning period.


Assuntos
Ração Animal/efeitos adversos , Colostro , Dieta/veterinária , Disbiose/veterinária , Microbioma Gastrointestinal , Sus scrofa/microbiologia , Doenças dos Suínos/prevenção & controle , Animais , Bovinos , Cruzamentos Genéticos , Dinamarca , Dieta/efeitos adversos , Disbiose/etiologia , Disbiose/microbiologia , Disbiose/prevenção & controle , Enterobacteriaceae/classificação , Enterobacteriaceae/crescimento & desenvolvimento , Enterobacteriaceae/isolamento & purificação , Enterobacteriaceae/metabolismo , Ácidos Graxos Voláteis/metabolismo , Fezes/microbiologia , Conteúdo Gastrointestinal/química , Conteúdo Gastrointestinal/microbiologia , Lactobacillus/classificação , Lactobacillus/crescimento & desenvolvimento , Lactobacillus/isolamento & purificação , Lactobacillus/metabolismo , Lactococcus/classificação , Lactococcus/crescimento & desenvolvimento , Lactococcus/isolamento & purificação , Lactococcus/metabolismo , Tipagem Molecular , Especificidade de Órgãos , Distribuição Aleatória , Sus scrofa/crescimento & desenvolvimento , Sus scrofa/imunologia , Suínos , Doenças dos Suínos/etiologia , Doenças dos Suínos/imunologia , Doenças dos Suínos/microbiologia , Desmame
20.
Expert Rev Anti Infect Ther ; 15(6): 605-612, 2017 06.
Artigo em Inglês | MEDLINE | ID: mdl-28395551

RESUMO

INTRODUCTION: Tigecycline, a derivative of minocycline, is an extended-spectrum antimicrobial agent. It has a restricted approval field in children and the experience of its adoption in clinical practice is reserved for cases of challenging infections. The aim of this review was to summarize evidence regarding the use of tigecycline in infants and children, focusing on the drug's clinical efficacy data and tolerability profile. Areas covered: We have conducted a literature search of the Cochrane Library, EMBASE, and MEDLINE databases, from their inception through 5 January 2017, using the following terms: tigecycline, newborn, infant, child, pediatrics, adolescent, human, clinical trial, and case report. Articles were excluded if they were redundant or not pertinent. Bibliographies of all relevant articles were also evaluated. Seventeen publications were included: 1 pharmacokinetic study, 16 case reports. In the selected publications, the patients' mean age was 4.45 years, 38.7% of children was <3 years old and favorable clinical response was achieved in 74.2% of cases. Expert commentary: Tigecycline may be a considerable option in life-threatening infections in pediatric patients. Its administration is well tolerated and has demonstrated a good clinical response in nonbacteremic patients. However, the available clinical records are limited and more studies are needed.


Assuntos
Infecções por Acinetobacter/tratamento farmacológico , Antibacterianos/uso terapêutico , Infecções por Enterobacteriaceae/tratamento farmacológico , Minociclina/análogos & derivados , Infecções Estafilocócicas/tratamento farmacológico , Infecções por Acinetobacter/microbiologia , Infecções por Acinetobacter/patologia , Acinetobacter baumannii/efeitos dos fármacos , Acinetobacter baumannii/crescimento & desenvolvimento , Acinetobacter baumannii/patogenicidade , Adolescente , Criança , Pré-Escolar , Enterobacteriaceae/efeitos dos fármacos , Enterobacteriaceae/crescimento & desenvolvimento , Enterobacteriaceae/patogenicidade , Infecções por Enterobacteriaceae/microbiologia , Infecções por Enterobacteriaceae/patologia , Humanos , Lactente , Recém-Nascido , Staphylococcus aureus Resistente à Meticilina/efeitos dos fármacos , Staphylococcus aureus Resistente à Meticilina/crescimento & desenvolvimento , Staphylococcus aureus Resistente à Meticilina/patogenicidade , Testes de Sensibilidade Microbiana , Minociclina/uso terapêutico , Infecções Estafilocócicas/microbiologia , Infecções Estafilocócicas/patologia , Tigeciclina , Resultado do Tratamento
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