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1.
Lett Appl Microbiol ; 75(2): 249-260, 2022 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-35429170

RESUMO

This study evaluated the effects of a fibre and phenolic-rich flour (IGF) prepared from Isabel grape by-products on the growth and metabolism of different probiotics and distinct bacterial populations part of the human intestinal microbiota during an in vitro colonic fermentation. IGF was submitted to simulated gastrointestinal digestion before use in the experiments. IGF favoured the growth of the probiotics Lactobacillus acidophilus La-05, L. casei L-26 and Bifidobacterium lactis Bb-12, with viable counts of >7 log CFU per ml, as well as caused decreases in pH values and increases in organic acid production in the growth medium during 48 h of cultivation. IGF increased the population of beneficial micro-organisms forming the human intestinal microbiota, particularly Lactobacillus spp., decreased the pH values, and increased the lactic acid and short-chain fatty acid (acetic, butyric and propionic acids) production during 24 h of in vitro colonic fermentation. These results indicate the potential prebiotic effects of IGF, which should represent a novel sustainable added-value ingredient with functional properties and gut-health benefits.


Assuntos
Microbiota , Probióticos , Vitis , Fermentação , Farinha , Humanos , Lactobacillus acidophilus/metabolismo , Fenóis/análise , Fenóis/farmacologia , Probióticos/metabolismo , Probióticos/farmacologia
2.
J Environ Manage ; 237: 595-608, 2019 May 01.
Artigo em Inglês | MEDLINE | ID: mdl-30826641

RESUMO

The purpose of this research was the preparation and photocatalytic evaluation of a novel nanocomposite (NC) based on Fe3O4/ZnO, to eliminate four persistent antibiotics in surface waters: sulfamethoxazole, trimethoprim, erythromycin and roxithromycin. Prior to the operation of the photocatalytic reactor, the influence of pH (3-9), catalyst concentration (50-800 mg L-1), oxidant dose (0-100 mg L-1) and concentration of different targets (10-100 µg L-1) on the catalytic efficiency was evaluated. The analysis of reaction kinetics showed that degradation processes of the four antibiotics followed a pseudo-first-order kinetic model. Antibiotics adsorption onto the nanocomposite surface depended on their electrostatic nature and played an important role when decreasing the initial concentration of antibiotics. In this context, kinetic rates were higher at lower initial levels of organic pollutants, which is a favourable effect from a practical application perspective. On the other hand, a synergistic effect of the available Fe in the nanocomposite was found, contributing to the oxidation of antibiotics by photo-Fenton as a secondary reaction. Then, a magnetic photocatalytic reactor was operated under optimal conditions. The enhanced photonic efficiency of Fe3O4/ZnO in the system, as well as the ease of the magnetic separation and catalyst reusability, indicate the viability of this reactor configuration.


Assuntos
Nanocompostos , Poluentes Químicos da Água , Óxido de Zinco , Antibacterianos , Catálise , Sulfametoxazol
3.
Chaos ; 28(6): 063112, 2018 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-29960390

RESUMO

This paper, based on the concept of symbolic correlation integral, introduces a set of symbolic recurrence plots and associated invariant measures, which are independent of the distance parameter, serving as a tool for quantifying the dynamic structure. These new measures allow the study of transient behavior, coexistence of attractors, bifurcations, and structural change. The final user does not have to choose the free distance parameter. An empirical application to electrocardiography data illustrates the use of symbolic recurrence measures.

4.
J Food Sci Technol ; 55(1): 42-51, 2018 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-29358794

RESUMO

Yam (Dioscorea spp) is an essential tuber crop for hundreds of millions of people in many African, Asian and South American countries. Considering in particular Southwest Nigeria, chips, flakes and flours are amongst the most common shelf-stable traditionally-processed yam products. This paper reports a systematic study on the proximate (moisture, protein, carbohydrate, fibre, fat, ash and gross energy) and mineral composition of these three food commodities sold in Nigerian markets. Results showed no significant differences in the moisture, crude protein and fibre content of all samples (10.0-12.3, 2.7-4.3 and 1.3-2.0 wt%, respectively). Gross energy was also comparable for all yam derived food items (between 3300 and 3507 kcal/kg), contradicting the common belief that yam flakes have lower nutritional value than chips and flours. Considering the mineral composition, Ca, Mg, P and K were the predominant macronutrients. Micronutrients such as Zn, Co, Mn and Cu were also detected. Significant differences existed between products, and their various sources (markets). Principal component analysis showed a direct correlation between ash content of the samples and the assessed macronutrients, irrespective of the market, or the seller of the commodities. This study confirmed that yam derived food stuffs have an adequate nutritional composition, irrespective of their form and/or origin.

5.
Crit Rev Food Sci Nutr ; 57(14): 3072-3083, 2017 Sep 22.
Artigo em Inglês | MEDLINE | ID: mdl-26529399

RESUMO

Anthocyanins have gathered the attention of the scientific community mostly due to their vast range of possible applications. They have been the center point of the research in many different fields, among which is food development, where their innate coloring, antioxidant capacity, and biological potential open interesting venues to the development of new food additives and functional foodstuffs. As the range of application grows, so does the necessity to obtain these compounds, and since they are naturally occurring, the most common way to obtain anthocyanins is to extract them from different plant sources, such as fruits and flowers. Several efforts have been made to develop methods that allow for better extraction yields and higher purification rates therefore this review aims to compile the information regarding extraction and purification procedures in a comprehensive manner.


Assuntos
Antocianinas/análise , Antioxidantes/análise , Flores/química , Frutas/química , Extratos Vegetais/análise , Antocianinas/isolamento & purificação , Antioxidantes/isolamento & purificação , Extratos Vegetais/isolamento & purificação
6.
J Appl Microbiol ; 122(6): 1547-1557, 2017 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-28370752

RESUMO

AIMS: Chitosan is a natural compound that has been validated as a viable antimicrobial agent against Staphylococcus aureus. With this work we sought to evaluate the planktonic and sessile sensitivity of methicillin-resistant S. aureus to chitosan's activity and evaluate if methicillin-resistant S. aureus (MRSA) would be more or less sensitive to chitosan's activity than methicillin-sensitive S. aureus (MSSA). METHODS AND RESULTS: A group comprised of reference strains and clinical multiresistant isolates of MSSA and MRSA were used. Methicilin resistance effect upon chitosan activity was assessed in planktonic setting and in different phases of sessile colonization, namely adhesion, biofilm formation and mature biofilm through biomass and metabolism inhibition. The results obtained showed that S. aureus methicillin resistance mechanism did not impair chitosan's activity as the highest bacterial susceptibility was registered for MRSA. Chitosan was highly effective in inhibiting MSSA and MRSA strains in both planktonic and sessile settings with biofilm inhibition percentages reaching as high as 90% for MRSA. CONCLUSIONS: Staphylococcus aureus methicillin resistance did not impair chitosan's antimicrobial and antibiofilm activities and MRSA and MSSA were inhibited both in planktonic and sessile settings at low concentrations with great efficacy. SIGNIFICANCE AND IMPACT OF THE STUDY: Considering the obtained results chitosan shows potential as an alternative for the control of biofilm-related recalcitrant MRSA infections.


Assuntos
Biofilmes/efeitos dos fármacos , Quitosana/farmacologia , Staphylococcus aureus Resistente à Meticilina/efeitos dos fármacos , Antibacterianos/farmacologia , Humanos , Resistência a Meticilina , Staphylococcus aureus Resistente à Meticilina/isolamento & purificação , Testes de Sensibilidade Microbiana
7.
Med Intensiva ; 41(5): 277-284, 2017.
Artigo em Inglês, Espanhol | MEDLINE | ID: mdl-27776936

RESUMO

OBJECTIVE: To study the effect of setting positive end-expiratory pressure (PEEP) in an individualized manner (based on highest static compliance) compared to setting PEEP according to FiO2 upon mortality at 28 and 90 days, in patients with different severity acute respiratory distress syndrome (ARDS). SETTING: A Spanish medical-surgical ICU. DESIGN: A post hoc analysis of a randomized controlled pilot study. PATIENTS: Patients with ARDS. INTERVENTIONS: Ventilation with low tidal volumes and pressure limitation at 30cmH2O, randomized in two groups according to the method used to set PEEP: FiO2-guided PEEP group according to FiO2 applied and compliance-guided group according to the highest compliance. PRIMARY VARIABLES OF INTEREST: Demographic data, risk factors and severity of ARDS, APACHE II and SOFA scores, daily Lung Injury Score, ventilatory measurements, ICU and hospital stay, organ failure and mortality at day 28 and 90 after inclusion. RESULTS: A total of 159 patients with ARDS were evaluated, but just 70 patients were included. Severe ARDS patients showed more organ dysfunction-free days at 28 days (12.83±10.70 versus 3.09±7.23; p=0.04) and at 90 days (6.73±22.31 vs. 54.17±42.14, p=0.03), and a trend toward lower 90-days mortality (33.3% vs. 90.9%, p=0.02), when PEEP was applied according to the best static compliance. Patients with moderate ARDS did not show these effects. CONCLUSIONS: In patients with severe ARDS, individualized PEEP selection based on the best static compliance was associated to lower mortality at 90 days, with an increase in organ dysfunction-free days at 28 and 90 days.


Assuntos
Complacência Pulmonar , Respiração com Pressão Positiva/métodos , Síndrome do Desconforto Respiratório/terapia , APACHE , Idoso , Feminino , Humanos , Tempo de Internação/estatística & dados numéricos , Masculino , Pessoa de Meia-Idade , Escores de Disfunção Orgânica , Oxigênio/análise , Projetos Piloto , Ensaios Clínicos Controlados Aleatórios como Assunto/estatística & dados numéricos , Síndrome do Desconforto Respiratório/mortalidade , Volume de Ventilação Pulmonar , Lesão Pulmonar Induzida por Ventilação Mecânica/etiologia , Lesão Pulmonar Induzida por Ventilação Mecânica/prevenção & controle
8.
J Appl Microbiol ; 121(3): 693-703, 2016 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-27349348

RESUMO

AIMS: The present work aimed to characterize the impact of an anthocyanin-rich blueberry extract upon the growth, adhesion and biofilm formation of several pathogens including some multiresistant bacteria. METHODS AND RESULTS: A group comprised of reference strains and clinical multiresistant isolates of Pseudomonas aeruginosa, Escherichia coli, Proteus mirabilis, Acinetobacter baumannii and Staphylococcus aureus, were used to screen for antimicrobial activity. Microbial growth was determined through the measurement of the optical density while adhesion and biofilm formation was determined using the standard crystal violet staining procedure. The results showed that, while blueberry extract was only effective in hindering the growth of Staph. aureus and E. coli, it was capable of significantly inhibiting biofilm formation and bacterial adhesion for all micro-organisms tested. CONCLUSIONS: The extract demonstrated a considerable potential as a natural, alternative antimicrobial capable of either interfering with microbial growth or hamper the adhesion to surfaces, with Staph. aureus proving to be the most susceptible micro-organism. SIGNIFICANCE AND IMPACT OF THE STUDY: The overall study demonstrates the potential of anthocyanin extracts as natural effective alternative antimicrobial agents. Additionally, the extract's capacity to reduce adhesion without reducing bacterial growth reduces the likeliness of resistance development while reducing the probability of infection.


Assuntos
Antibacterianos/isolamento & purificação , Bactérias/efeitos dos fármacos , Mirtilos Azuis (Planta)/química , Extratos Vegetais/farmacologia , Antocianinas/análise , Bactérias/classificação , Aderência Bacteriana/efeitos dos fármacos , Fenômenos Fisiológicos Bacterianos , Biofilmes/efeitos dos fármacos , Cinética , Testes de Sensibilidade Microbiana , Extratos Vegetais/química , Extração em Fase Sólida
9.
Biofouling ; 32(8): 853-60, 2016 09 13.
Artigo em Inglês | MEDLINE | ID: mdl-27434592

RESUMO

Phenolic acids are a particular group of small phenolic compounds which have exhibited some anti-biofilm activity, although the link between their activity and their intrinsic pH is not clear. Therefore, the present work examined the anti-biofilm activity (inhibition of biomass and metabolic activity) of phenolic acids in relation to the environmental pH, as well as other physico-chemical properties. The results indicate that, while Escherichia coli was not inhibited by the phenolic acids, both methicillin resistant Staphylococcus aureus and methicillin resistant Staphylococcus epidermidis were susceptible to the action of all phenolic acids, with the pH playing a relevant role in the activity: a neutral pH favored MRSE inhibition, while acidic conditions favored MRSA inhibition. Some links between molecular polarity and size were associated only with their potential as metabolic inhibitors, with the overall interactions hinting at a membrane-based mechanism for MRSA and a cytoplasmic effect for MRSE.


Assuntos
Antibacterianos/farmacologia , Biofilmes/efeitos dos fármacos , Escherichia coli/efeitos dos fármacos , Hidroxibenzoatos/farmacologia , Staphylococcus aureus Resistente à Meticilina/efeitos dos fármacos , Staphylococcus epidermidis/efeitos dos fármacos , Antibacterianos/química , Biomassa , Escherichia coli/metabolismo , Escherichia coli/fisiologia , Concentração de Íons de Hidrogênio , Hidroxibenzoatos/química , Staphylococcus aureus Resistente à Meticilina/metabolismo , Staphylococcus aureus Resistente à Meticilina/fisiologia , Testes de Sensibilidade Microbiana , Peso Molecular , Staphylococcus epidermidis/metabolismo , Staphylococcus epidermidis/fisiologia
10.
Med Intensiva ; 40(5): 289-97, 2016.
Artigo em Inglês, Espanhol | MEDLINE | ID: mdl-26706825

RESUMO

OBJECTIVE: To evaluate mortality and functional status at one year of follow-up in patients>75 years of age who survive Intensive Care Unit (ICU) admission of over 14 days. DESIGN: A prospective observational study was carried out. SETTING: A Spanish medical-surgical ICU. PATIENTS: Patients over 75 years of age admitted to the ICU. PRIMARY VARIABLES OF INTEREST: ICU admission: demographic data, baseline functional status (Barthel index), baseline mental status (Red Cross scale of mental incapacity), severity of illness (APACHE II and SOFA), stay and mortality. One-year follow-up: hospital stay and mortality, functional and mental status, and one-year follow-up mortality. RESULTS: A total of 176 patients were included, of which 22 had a stay of over 14 days. Patients with prolonged stay did not show more ICU mortality than those with a shorter stay in the ICU (40.9% vs 25.3% respectively, P=.12), although their hospital (63.6% vs 33.8%, P<.01) and one-year follow-up mortality were higher (68.2% vs 41.2%, P=.02). Among the survivors, one-year mortality proved similar (87.5% vs 90.6%, P=.57). These patients presented significantly greater impairment of functional status at hospital discharge than the patients with a shorter ICU stay, and this difference persisted after three months. The levels of independence at one-year follow-up were never similar to baseline. No such findings were observed in relation to mental status. CONCLUSIONS: Patients over 75 years of age with a ICU stay of more than 14 days have high hospital and one-year follow-up mortality. Patients who survive to hospital admission did not show greater mortality, though their functional dependency was greater.


Assuntos
Unidades de Terapia Intensiva , Tempo de Internação , APACHE , Idoso , Idoso de 80 Anos ou mais , Grupos Diagnósticos Relacionados , Feminino , Seguimentos , Humanos , Vida Independente , Masculino , Testes de Estado Mental e Demência , Escores de Disfunção Orgânica , Alta do Paciente , Estudos Prospectivos , Recuperação de Função Fisiológica , Espanha/epidemiologia , Análise de Sobrevida , Centros de Atenção Terciária
11.
Eur J Clin Microbiol Infect Dis ; 34(6): 1255-62, 2015 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-25754770

RESUMO

Daptomycin may offer an antibacterial alternative for the treatment of endophthalmitis caused by methicillin-resistant Staphylococcus aureus (MRSA) and other potential agents. In the present project, mucoadhesive chitosan-coated alginate (CS-ALG) nanoparticles are proposed as an effective delivery system for daptomycin permeation across ocular epithelia, with potential for the treatment of bacterial endophthalmitis. CS-ALG nanoparticles were prepared by ionotropic pre-gelation of an alginate core followed by chitosan polyelectrolyte complexation, and characterized regarding particle size, polydispersity, and zeta potential. The encapsulation efficiency was determined and antimicrobial activity was also tested after encapsulation of the antibiotic. Also, in vitro ocular permeability of free daptomycin and encapsulation into chitosan and CS-ALG nanoparticles was evaluated using ocular epithelial cell culture models. Formulated daptomycin-loaded CS-ALG nanoparticles were negatively charged, with a size range of 380-420 nm, suitable for ocular application. The encapsulation efficiency was between 79 and 92 %, with decreasing alginate:daptomycin mass ratios. The antibacterial activity of daptomycin against major microorganisms responsible for bacterial endophthalmitis was not affected by encapsulation into nanoparticles. Daptomycin permeability was up to 16 % (chitosan nanoparticles) and 9 % (CS-ALG nanoparticles) through corneal cell monolayer, and 18 % (chitosan nanoparticles) and 12 % (CS-ALG nanoparticles) for retinal cell monolayer after 4 h, demonstrating epithelial retention of the drug compared to free drug. The developed daptomycin-loaded CS-ALG nanoparticles seem to be an interesting and potential system for ocular daptomycin delivery and treatment of bacterial endophthalmitis.


Assuntos
Antibacterianos/farmacologia , Daptomicina/farmacologia , Portadores de Fármacos/metabolismo , Nanopartículas/metabolismo , Alginatos/metabolismo , Antibacterianos/metabolismo , Infecções Bacterianas/tratamento farmacológico , Linhagem Celular , Quitosana/metabolismo , Daptomicina/metabolismo , Portadores de Fármacos/síntese química , Endoftalmite/tratamento farmacológico , Ácido Glucurônico/metabolismo , Ácidos Hexurônicos/metabolismo , Humanos , Testes de Sensibilidade Microbiana
12.
J Appl Microbiol ; 116(1): 32-8, 2014 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-24107088

RESUMO

AIMS: The main objective of this study was to evaluate the capacity of wild mushroom extracts to potentiate the action of standard antibiotics, through synergisms that allow a decrease in their therapeutic doses and ultimately contribute to the reduction of resistances. METHODS AND RESULTS: Wild mushroom extracts were applied to different multiresistant micro-organisms (Escherichia coli, extended-spectrum beta-lactamase-producing (ESBL) E. coli and methicillin-resistant Staphylococcus aureus (MRSA), combined with commercial antibiotics (penicillin, ampicillin, amoxicillin/clavulanic acid, cefoxitin, ciprofloxacin, cotrimoxazol, levofloxacin). Microdilution method was used to determine minimum inhibitory concentrations (MICs). The results obtained showed higher synergistic effects against MRSA than against E. coli. Mycena rosea and Fistulina hepatica were the best extracts for synergistic effects against MRSA. The efficiency of Russula delica extract against E. coli 1 (resistant to ampicillin, ciprofloxacin and trimethoprim/sulfasoxazole) and E. coli 2 (resistant to amoxicillin/clavulanic acid and ampicillin) was higher than that of Leucopaxillus giganteus extract; nevertheless, the latter extract exhibited better synergistic effects against ESBL E. coli. CONCLUSIONS: This study shows that, similarly to plants, some mushroom extracts can potentiate the action of antibiotics extensively used in clinical practice for Gram-positive or Gram-negative bacteria, with positive action even against multiresistant bacteria. SIGNIFICANCE AND IMPACT OF THE STUDY: Mushroom extracts could decrease therapeutic doses of standard antibiotics and reduce micro-organism's resistance to those drugs.


Assuntos
Antibacterianos , Staphylococcus aureus Resistente à Meticilina , Agaricales , Antibacterianos/farmacologia , Bactérias/efeitos dos fármacos , Escherichia coli/efeitos dos fármacos , Humanos , Staphylococcus aureus Resistente à Meticilina/efeitos dos fármacos , Testes de Sensibilidade Microbiana
13.
Med Intensiva ; 38(8): 498-501, 2014 Nov.
Artigo em Inglês, Espanhol | MEDLINE | ID: mdl-24485531

RESUMO

Current treatment of acute respiratory distress syndrome is based on ventilatory support with a lung protective strategy, avoiding the development of iatrogenic injury, including ventilator-induced lung injury. One of the mechanisms underlying such injury is atelectrauma, and positive end-expiratory pressure (PEEP) is advocated in order to avoid it. The indicated PEEP level has not been defined, and in many cases is based on the patient oxygen requirements for maintaining adequate oxygenation. However, this strategy does not consider the mechanics of the respiratory system, which varies in each patient and depends on many factors-including particularly the duration of acute respiratory distress syndrome. A review is therefore made of the different methods for adjusting PEEP, focusing on the benefits of individualized application.


Assuntos
Respiração com Pressão Positiva/métodos , Síndrome do Desconforto Respiratório/terapia , Hemodinâmica , Humanos , Complacência Pulmonar , Oxigênio/sangue , Medicina de Precisão , Atelectasia Pulmonar/terapia , Síndrome do Desconforto Respiratório/fisiopatologia , Mecânica Respiratória
14.
Radiologia ; 56(4): 290-4, 2014.
Artigo em Espanhol | MEDLINE | ID: mdl-23183275

RESUMO

Sonoelastography combines elastography and B mode ultrasonography to show parameters related to the structural organization of tissues in real time. Thus, this noninvasive technique shows us the mechanical characteristics of each tissue. The different elastography techniques (qualitative and quantitative, in ultrasonography or magnetic resonance imaging) are based on the hypothesis that soft tissues are more deformable than stiff tissues and that these differences can be captured in images. Elastography adds a new perspective to conventional ultrasonography: it reflects the stiffness of the tissues, and this information, together with the anatomic information from B mode imaging and the vascular information from Doppler, is key for the diagnosis. This article aims to provide a brief summary of what elastography is, the different types of elastography, and the range of possible applications of this technique.


Assuntos
Técnicas de Imagem por Elasticidade , Técnicas de Imagem por Elasticidade/métodos , Humanos
15.
J Appl Microbiol ; 115(6): 1411-9, 2013 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-23910049

RESUMO

AIMS: The aim of this study was to determine the biodiversity of the skin staphylococcal community from patients with atopic dermatitis (AD) and superantigen (SAg) detection from Staphylococcus aureus isolates. METHODS AND RESULTS: In this study, we developed a novel multiplex PCR that allows the identification and discrimination of bacteria belonging to the Staphylococcus genus both Staph. aureus and coagulase-negative Staphylococcus - Staph. capitis, Staph. epidermidis, Staph. haemolyticus and Staph. hominis isolated from the skin of patients with AD. In addition, a multiplex PCR assay that allows the rapid screening of the 19 genes that encode staphylococcal enterotoxins (SEs), SE-like toxins and toxic shock syndrome toxin-1 was also performed and applied in Staph. aureus isolates. The microflora of the skin of patients with AD was dominated by Staph. aureus (69 isolates, 35·6%) followed by Staph. epidermidis (59 isolates, 30·4%) species. The SElM and SElN genes were the most frequently detected in our study (15 isolates, 71·4%), followed by SEG and SElO (14 isolates, 66·7%). CONCLUSIONS: Our molecular-based approach successfully identified the staphylococcal microflora that was relatively specific to patients with AD. Considering skin colonization and expression of virulence factors, the Staph. aureus may play a relevant role in AD pathophysiology. SIGNIFICANCE AND IMPACT OF THE STUDY: This ability to classify disease-related microbial species provides new insights into the relevance of those microbes in human disorders.

16.
J Appl Microbiol ; 115(2): 346-57, 2013 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-23510516

RESUMO

AIM AND METHODS: Although the antimicrobial activity of extracts from several mushroom species has been reported, studies with the individual compounds present in that extracts are scarce. Herein, the antimicrobial activity of different phenolic compounds identified and quantified in mushroom species from all over the world was evaluated. Furthermore, a structure-activity relationship (SAR) analysis and molecular docking studies were performed, in order to provide insights into the mechanism of action of potential antimicrobial drugs for resistant micro-organisms. RESULTS: 2,4-Dihydroxybenzoic and protocatechuic acids were the phenolic compounds with higher activity against the majority of Gram-negative and Gram-positive bacteria. Furthermore, phenolic compounds inhibited more MRSA than methicillin-susceptible Staphylococcus aureus. MRSA was inhibited by 2,4-dihydroxybenzoic, vanillic, syringic (MICs = 0.5 mg ml(-1) ) and p-coumaric (MIC = 1 mg ml(-1) ) acids, while these compounds at the same concentrations had no inhibitory effects against methicillin-susceptible Staph. aureus. CONCLUSIONS: The presence of carboxylic acid (COOH), two hydroxyl (OH) groups in para and ortho positions of the benzene ring and also a methoxyl (OCH3 ) group in the meta position seems to be important for anti-MRSA activity. SIGNIFICANCE AND IMPACT OF THE STUDY: Phenolic compounds could be used as antimicrobial agents, namely against some micro-organisms resistant to commercial antibiotics.


Assuntos
Agaricales/química , Antibacterianos/química , Antibacterianos/farmacologia , Fenóis/química , Fenóis/farmacologia , Bactérias Gram-Negativas/efeitos dos fármacos , Bactérias Gram-Positivas/efeitos dos fármacos , Testes de Sensibilidade Microbiana , Simulação de Acoplamento Molecular , Proteínas de Ligação às Penicilinas/química , Relação Estrutura-Atividade
17.
Anaerobe ; 20: 27-31, 2013 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-23454497

RESUMO

The main aim of this work was to access the potential use of high and low molecular weight chitosans as potential oral antimicrobials, particularly as antibiofilm agents. Chitosan's interference with Streptococcus mutans capability to adhere and form biofilms was assessed. Additionally the effect upon mature and polymicrobial biofilms was also evaluated. The results obtained showed that chitosan was capable of interfering with S. mutans adhesion and primary biofilm formation. This action was observed up to a week with little to none decrease in efficiency. In addition chitosan was capable of inhibiting biofilms formed by two microorganisms and was capable of acting upon mature biofilms leading to significant reductions (94%) in biofilm survival. However clear statistical differences (p < 0.05) were registered in all assays with, in most assays, HMw chitosan presenting higher efficiency than LMw chitosan. Considering this results chitosan's potential as a valid alternative to traditional antimicrobials in oral health it's evident.


Assuntos
Aderência Bacteriana/efeitos dos fármacos , Biofilmes/efeitos dos fármacos , Quitosana/farmacologia , Streptococcus mutans/efeitos dos fármacos , Biofilmes/crescimento & desenvolvimento , Humanos , Testes de Sensibilidade Microbiana , Boca/efeitos dos fármacos , Boca/microbiologia , Streptococcus mutans/crescimento & desenvolvimento , Streptococcus mutans/fisiologia
18.
J Environ Manage ; 121: 87-95, 2013 May 30.
Artigo em Inglês | MEDLINE | ID: mdl-23524400

RESUMO

Selected bacterial strains were immobilised on the surface of hydroxyapatite (Ca10(PO4)6(OH)2 - HAp) of natural origin (fish bones). The capacity of the material, alone and in combination with the bacterial strains to act as heavy metal removers from aqueous streams was assessed. Pseudomonas fluorescens (S3X), Microbacterium oxydans (EC29) and Cupriavidus sp. (1C2) were chosen based on their resistance to heavy metals and capacity of adsorbing the metals. These systems were tested using solutions of Zn(II), Cd(II) and in solutions containing both metals. A synergistic effect between the strains and HAp, which is effective in removing the target heavy metals on its own, was observed, as the combination of HAp with the bacterial strains led to higher adsorption capacity for both elements. For the solutions containing only one metal the synergistic effect was greater for higher metal concentrations; 1C2 and EC29 were the most effective strains for Zn(II) and Cd(II) respectively, while S3X was less effective. Overall, an almost four-fold increase was observed for the maximum adsorption capacity for Zn(II) when 1C2 was employed - 0.433 mmol/g in comparison of 0.121 mmol/g for the unmodified HAp. For Cd(II), on the other hand, an almost three-fold increase was registered with EC29 bacterial strain - 0.090 vs 0.036 mmol/g for the unmodified HAp. When the solutions containing both metals were tested, the effect was more marked for lower concentrations.


Assuntos
Biofilmes , Cupriavidus/metabolismo , Durapatita , Metais Pesados/isolamento & purificação , Pseudomonas fluorescens/metabolismo , Poluentes Químicos da Água/isolamento & purificação , Adsorção , Animais , Osso e Ossos , Gadus morhua , Metais Pesados/metabolismo , Poluentes Químicos da Água/metabolismo
19.
Food Chem ; 410: 135319, 2023 Jun 01.
Artigo em Inglês | MEDLINE | ID: mdl-36634564

RESUMO

The tomato processing industry is one of the world's most important markets. This industry aims to optimise production, minimise energy costs and waste streams while ensuring high-quality products. This sector produces substantial amounts of by-products frequently disposed of as waste rather than reintroducing them with a new intent into the supply chain. However, these by-products are rich in bioactive compounds (BC), including carotenoids, fibre, which exhibit antioxidant, anti-inflammatory and chemopreventive properties, and cardiovascular protection. Reusing these compounds is favourable to reducing the environmental impact and enables the development of added-value products with various possible uses such as food and feed additives, nutraceuticals, cosmeceuticals, etc. This review summarises relevant issues towards the recovery and valorisation of BC from industrial tomato by-products within a circular economy context.


Assuntos
Solanum lycopersicum , Humanos , Carotenoides/análise , Antioxidantes , Manipulação de Alimentos , Suplementos Nutricionais
20.
Phytomedicine ; 115: 154824, 2023 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-37119762

RESUMO

BACKGROUND: Every day the skin is constantly exposed to several harmful factors that induce oxidative stress. When the cells are incapable to maintain the balance between antioxidant defenses and reactive oxygen species, the skin no longer can keep its integrity and homeostasis. Chronic inflammation, premature skin aging, tissue damage, and immunosuppression are possible consequences induced by sustained exposure to environmental and endogenous reactive oxygen species. Skin immune and non-immune cells together with the microbiome are essential to efficiently trigger skin immune responses to stress. For this reason, an ever-increasing demand for novel molecules capable of modulating immune functions in the skin has risen the level of their development, particularly in the field of natural product-derived molecules. PURPOSE: In this review, we explore different classes of molecules that showed evidence in modulate skin immune responses, as well as their target receptors and signaling pathways. Moreover, we describe the role of polyphenols, polysaccharides, fatty acids, peptides, and probiotics as possible treatments for skin conditions, including wound healing, infection, inflammation, allergies, and premature skin aging. METHODS: Literature was searched, analyzed, and collected using databases, including PubMed, Science Direct, and Google Scholar. The search terms used included "Skin", "wound healing", "natural products", "skin microbiome", "immunomodulation", "anti-inflammatory", "antioxidant", "infection", "UV radiation", "polyphenols", "polysaccharides", "fatty acids", "plant oils", "peptides", "antimicrobial peptides", "probiotics", "atopic dermatitis", "psoriasis", "auto-immunity", "dry skin", "aging", etc., and several combinations of these keywords. RESULTS: Natural products offer different solutions as possible treatments for several skin conditions. Significant antioxidant and anti-inflammatory activities were reported, followed by the ability to modulate immune functions in the skin. Several membrane-bound immune receptors in the skin recognize diverse types of natural-derived molecules, promoting different immune responses that can improve skin conditions. CONCLUSION: Despite the increasing progress in drug discovery, several limiting factors need future clarification. Understanding the safety, biological activities, and precise mechanisms of action is a priority as well as the characterization of the active compounds responsible for that. This review provides directions for future studies in the development of new molecules with important pharmaceutical and cosmeceutical value.


Assuntos
Produtos Biológicos , Envelhecimento da Pele , Humanos , Espécies Reativas de Oxigênio , Produtos Biológicos/farmacologia , Produtos Biológicos/uso terapêutico , Produtos Biológicos/química , Antioxidantes/farmacologia , Antioxidantes/uso terapêutico , Antioxidantes/química , Inflamação/tratamento farmacológico , Anti-Inflamatórios/farmacologia , Anti-Inflamatórios/uso terapêutico , Polifenóis , Peptídeos/química , Polissacarídeos
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