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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.
Lett Appl Microbiol ; 75(3): 565-577, 2022 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-34687563

RESUMO

This study aimed to evaluate the inhibitory effects of phenolic-rich extracts from acerola (Malpighia emarginata D.C., PEA), cashew apple (Anacardium occidentale L., PEC) and mango (Mangifera indica L., PEM) by-products on distinct enterotoxigenic Escherichia coli (ETEC) strains. The capability of PEA and PEC of impairing various physiological functions of ETEC strains was investigated with multiparametric flow cytometry. Procyanidin B2 , myricetin and p-coumaric acid were the major phenolic compounds in PEA, PEC and PEM, respectively. PEA and PEC had lower minimum inhibitory concentration (MIC) and minimum bactericidal concentration (MBC) (MIC: 31·25 mg ml-1 ; MBC: 62·5 mg ml-1 ) on ETEC strains than PEM (MIC and MIC: >1000 mg ml-1 ). PEA and PEC (15·6, 31·2, 62·5 mg ml-1 ) caused viable count reductions (P < 0·05) on ETEC strains after 24 h of exposure, notably the ≥3 log reductions caused by 62·5 mg ml-1 . The 24 h exposure of ETEC strains to PEA and PEC (31·2, 62·5 mg ml-1 ) led to high sizes of cell subpopulations with concomitant impairments in cell membrane polarization and permeability, as well as in enzymatic, respiratory and efflux activities. PEA and PEC are effective in inhibiting ETEC through a multi-target action mode with disturbance in different physiological functions.


Assuntos
Anacardium , Escherichia coli Enterotoxigênica , Infecções por Escherichia coli , Mangifera , Fenóis/farmacologia , Extratos Vegetais/farmacologia
3.
J Dairy Sci ; 104(1): 179-197, 2021 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-33131813

RESUMO

Cheeses are able to serve as suitable matrices for supplying probiotics to consumers, enabling appropriate conditions for bacteria to survive gastric transit and reach the gut, where they are assumed to promote beneficial processes. The present study aimed to evaluate the microbiological, immunological, and histological changes in the gut of Salmonella Enteritidis-challenged rats fed goat cheese supplemented with the probiotic strain Lactobacillus rhamnosus EM1107. Thirty male albino Wistar rats were randomly distributed into 5 experimental groups with 6 animals each: negative (NC) and positive (PtC) control groups, control goat cheese (CCh), goat cheese added with L. rhamnosus EM1107 (LrCh), and L. rhamnosus EM1107 only (EM1107). All animals, except NC group were challenged with Salmonella Enteritidis (109 cfu in 1 mL of saline through oral gavage). Microbial composition was assessed with high-throughput 16S rRNA sequencing by means of Illumina MiSeq (Illumina, San Diego, CA). Nuclear factor kappa B (NF-κB) from the animal cecum tissue was determined by real-time PCR and interleukins (TNF-α, IL-1ß, IL-10, and IFN-γ) by means of ELISA. Myeloperoxidase and malondialdehyde levels were determined biochemically. The administration of the L. rhamnosus EM1107 probiotic strain, either as a pure culture or added to a cheese matrix, was able to reduce Salmonella colonization in the intestinal lumen and lessen tissue damage compared with rats from PtC group. In addition, the use of cheese for the probiotic strain delivery (LrCh) was associated with a marked shift in the gut microbiota composition toward the increase of beneficial organisms such as Blautia and Lactobacillus and a reduction in NF-κB expression. These findings support our hypothesis that cheeses might be explored as functional matrices for the efficacious delivery of probiotic strains to consumers.


Assuntos
Queijo/microbiologia , Cabras , Intestinos/imunologia , Intestinos/microbiologia , Lacticaseibacillus rhamnosus/metabolismo , Probióticos , Salmonella enteritidis/imunologia , Animais , Ceco/metabolismo , Ceco/microbiologia , Microbioma Gastrointestinal , Masculino , RNA Ribossômico 16S , Ratos , Ratos Wistar
4.
J Appl Microbiol ; 130(4): 1323-1336, 2021 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-32808408

RESUMO

AIMS: This study evaluated whether by-products from industrial processing of acerola (Malpighia glabra L.; AB) and guava (Psidium guajava L.; GB) fruit may stimulate the growth and metabolism of probiotic Lactobacillus and Bifidobacterium and induce changes in human colonic microbiota. METHODS AND RESULTS: The ability of non-digested and digested AB or GB to stimulate the growth ad metabolism of Lactobacillus acidophilus LA-05, Lactobacillus casei L-26 and Bifidobacterium animalis subsp. lactis BB-12 was evaluated. Changes in populations of distinct bacterial groups of human colonic microbiota induced by digested AB and GB were evaluated using an in vitro colonic fermentation system. Non-digested and digested AB and GB favoured probiotic growth. No difference among counts of probiotics in media with glucose, fructooligosaccharides and non-digested and digested AB and GB was found during a 48-h cultivation. Cultivation of probiotics in media with non-digested and digested AB and GB resulted in decreased pH, increased organic acid production and sugar consumption over time. Digested AB and GB caused overall beneficial changes in abundance of Bifidobacterium spp., Lactobacillus-Enterococcus, Eubacterium rectall-Clostridium coccoides and Bacteroides-Provotella populations, besides to decrease the pH and increase the short-chain fatty acid production during a 24-h in vitro colonic fermentation. CONCLUSION: AB and GB could be novel prebiotic ingredients because they can stimulate the growth and metabolism of probiotics and induce overall beneficial changes in human colonic microbiota. SIGNIFICANCE AND IMPACT OF THE STUDY: AB and GB stimulated the growth and metabolism of probiotics, in addition to induce beneficial alterations in human colonic microbiota composition and increase short-chain fatty acid production. These results characterize AB and GB as potential prebiotic ingredients and fruit processing by-products as sources of added-value compounds.


Assuntos
Bifidobacterium animalis/crescimento & desenvolvimento , Colo/microbiologia , Lactobacillus/crescimento & desenvolvimento , Malpighiaceae/metabolismo , Prebióticos/análise , Probióticos/análise , Psidium/metabolismo , Resíduos/análise , Bifidobacterium animalis/metabolismo , Clostridiales , Ácidos Graxos Voláteis/metabolismo , Fermentação , Frutas/química , Frutas/metabolismo , Microbioma Gastrointestinal , Humanos , Lactobacillus/metabolismo , Lactobacillus acidophilus/crescimento & desenvolvimento , Malpighiaceae/química , Oligossacarídeos/análise , Oligossacarídeos/metabolismo , Probióticos/metabolismo , Psidium/química
5.
Benef Microbes ; 11(8): 779-790, 2020 Dec 02.
Artigo em Inglês | MEDLINE | ID: mdl-33191778

RESUMO

Inflammatory bowel diseases (IBD) are chronic processes involving a deregulated immune response against intestinal microbiota in genetically susceptible individuals. Ulcerative colitis (UC) is an IBD restricted to colonic mucosa and its chronicity is a predisposing factor for colorectal cancer (CRC). Probiotics have been investigated as an adjuvant treatment for UC, and Escherichia coli Nissle 1917 (EcN) was the focus of our investigation. The aim of this study was to investigate the preventive effect of the EcN probiotic in an experimental model of chronic colitis in germ-free (GF) and conventional (CV) mice. CV female mice were used for clinical, immunological and permeability experiments. GF mice were used for a faecal microbiota transplantation assay. To induce colitis, three cycles of 3.0% dextran sulphate sodium (DSS) were administered to the animals. For probiotic treatment, the mice received a daily intragastric gavage of 9.0 log10 cfu of EcN, beginning 10 days before colitis induction and continuing until the end of the experiment. EcN presented beneficial effects when administered preventively. Daily Disease Activity Index (DAI) evolution demonstrated significant difference in remission periods after the first two DSS cycles and during the third one. Reduction in bacterial translocation after probiotic treatment indicated protection of the intestinal barrier. Associated with mucosal preservation, restoration of secretory immunoglobulin A levels and reduction of interleukin (IL)-5, IL-13, tumour necrosis factor and interferon-γ levels were observed in EcN treatment. Finally, when microbiota modification was verified, 16S rRNA-based compositional analysis showed variation of intestinal microbiota between the control and colitis groups. After faecal transplantation using GF mice, it was observed that EcN treatment in CV mice might result in modulated intestinal microbiota. This was observed indirectly in the reduced daily DAI, when colitis was compared with treated group. In conclusion, EcN presented beneficial effects in this model, suggesting its usefulness for treating UC.


Assuntos
Colite Ulcerativa/prevenção & controle , Escherichia coli/fisiologia , Transplante de Microbiota Fecal , Mucosa Intestinal/microbiologia , Probióticos/farmacologia , Animais , Colo/patologia , Sulfato de Dextrana/toxicidade , Modelos Animais de Doenças , Escherichia coli/classificação , Feminino , Microbioma Gastrointestinal/fisiologia , Vida Livre de Germes , Imunoglobulina A/análise , Interferon gama/sangue , Interleucina-13/sangue , Interleucina-5/sangue , Mucosa Intestinal/patologia , Camundongos , RNA Ribossômico 16S/genética , Fator de Necrose Tumoral alfa/sangue
6.
J Appl Microbiol ; 128(2): 376-386, 2020 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-31448524

RESUMO

AIMS: This study evaluated the efficacy of essential oil from Origanum vulgare L. (oregano; OVEO) and Rosmarinus officinalis L. (rosemary; ROEO) to inactivate sessile cells of Salmonella enterica serovar Enteritidis 86 (SE86) in young and mature biofilms formed on stainless steel. METHODS AND RESULTS: Ultrastructural alterations and damage in different physiological functions caused by OVEO and ROEO in noncultivable sessile cells of SE86 were investigated using scanning electron microscopy and flow cytometry. OVEO (2·5 µl ml-1 ) and ROEO (40 µl ml-1 ) were effective to eradicate young and mature biofilms formed by SE86 sessile cells on stainless steel surfaces; however, the efficacy varied with exposure time. OVEO and ROEO caused alterations in morphology of SE86 sessile cells, inducing the occurrence of bubbles or spots on cell surface. OVEO and ROEO compromised membrane polarization, permeability and efflux activity in noncultivable SE86 sessile cells. These findings show that OVEO and ROEO act by a multitarget mechanism on SE86 membrane functions. CONCLUSIONS: ROEO and OVEO showed efficacy to eradicate SE86 sessile cells in preformed biofilms on stainless steel, displaying a time-dependent effect and multitarget action mode on bacterial cell membrane. SIGNIFICANCE AND IMPACT OF THE STUDY: The study provides for the first time the effects of OVEO and ROEO on morphology and physiological functions of noncultivable sessile cells of S. Enteritidis biofilms preformed on stainless steel surfaces.


Assuntos
Biofilmes/efeitos dos fármacos , Óleos Voláteis/farmacologia , Origanum/química , Óleos de Plantas/farmacologia , Rosmarinus/química , Salmonella enteritidis/efeitos dos fármacos , Salmonella enteritidis/crescimento & desenvolvimento , Salmonella enteritidis/fisiologia , Aço Inoxidável/análise
7.
J Dairy Sci ; 102(8): 6756-6765, 2019 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-31178187

RESUMO

Fermented whey dairy beverages are dairy products obtained by fermentation from a mixture of milk and whey. These beverages have important health benefits, which could be improved with the addition of probiotic cultures. This study assessed the protective effect of the cosupplementation of a probiotic culture (Lactobacillus casei 01) with a fermented whey dairy beverage against infection by Salmonella enterica ssp. enterica serovar Typhimurium in a murine model. Two fermented whey dairy beverages were prepared: conventional (FWB; starter culture) and probiotic (PFWB; starter and probiotic cultures). In the first set of experiments, Balb/C female mice were treated with FWB or PFWB, challenged with Salmonella Typhimurium, and analyzed for clinical signs, weight loss, and mortality for 20 d postinfection. In the second set of experiments, mice were treated with FWB or PFWB, challenged with Salmonella Typhimurium, and killed on d 10 postinfection. The liver, colon, and ileum were used for myeloperoxidase, eosinophil peroxidase, and histological analysis and translocation to the liver. The contents from the small intestine were used for secretory IgA determination. The FWB treatment showed a better effect on animal survival (70%), translocation of the pathogen to the liver (2 out of 10), histopathology (fewer lesions), and inflammation than PFWB, which presented 50% animal survival, translocation in 5 out of 10 animals, and higher lesions. The control group presented 40% animal survival, translocation in 6 out of 10 animals, and severe lesions. Therefore, FWB was deemed to have a greater protective effect against Salmonella Typhimurium infection in the murine model compared with PFWB.


Assuntos
Produtos Fermentados do Leite , Salmonelose Animal/prevenção & controle , Salmonella typhimurium , Soro do Leite , Animais , Bebidas , Feminino , Promoção da Saúde , Imunoglobulina A Secretora/análise , Inflamação/prevenção & controle , Intestino Delgado/imunologia , Intestino Delgado/patologia , Lacticaseibacillus casei/fisiologia , Fígado/microbiologia , Fígado/patologia , Camundongos , Camundongos Endogâmicos BALB C , Probióticos , Salmonelose Animal/imunologia , Salmonelose Animal/patologia , Proteínas do Soro do Leite
8.
Microb Pathog ; 130: 259-270, 2019 May.
Artigo em Inglês | MEDLINE | ID: mdl-30917922

RESUMO

Fruits are among the main natural sources of phenolic compounds (PC). These compounds exert important antioxidant properties primarily associated with the presence of hydroxyl groups in their molecular structure. Additionally, the antibacterial effects of fruit phenolic-rich extracts or individual PC commonly found in fruits have been an emerging research focus in recent years. This review discusses by first time the available literature regarding the inhibitory effects of fruit PC on pathogenic bacteria, including not only their direct effects on bacterial growth and survival, but also their effects on virulence factors and antibiotic resistance, as well as the possible mechanism underlying these inhibitory properties. The results of the retrieved studies show overall that the antibacterial effects of fruit PC vary with the target bacteria, type of PC and length of exposure to these compounds. The type of solvent and procedures used for extraction and fruit cultivar also seem to influence the antibacterial effects of phenolic-rich fruit extracts. Fruit PC have shown wide-spectrum antibacterial properties besides being effective antibiotic resistance modifying agents in pathogenic bacteria and these effects have shown to be associated with interruption of efflux pump expression/function. Furthermore, fruit PC can cause down regulation of a variety of genes associated with virulence features in pathogenic bacteria. Results of available studies indicate the depolarization and alteration of membrane fluidity as mechanisms underlying the inhibition of pathogenic bacteria by fruit PC. These data reveal fruit PC have potential antimicrobial properties, which should be rationally exploited in solutions to control pathogenic bacteria.


Assuntos
Antibacterianos/farmacologia , Bactérias/efeitos dos fármacos , Frutas/química , Fenóis/farmacologia , Compostos Fitoquímicos/farmacologia , Antibacterianos/isolamento & purificação , Viabilidade Microbiana/efeitos dos fármacos , Fenóis/isolamento & purificação , Compostos Fitoquímicos/isolamento & purificação , Virulência/efeitos dos fármacos
9.
Benef Microbes ; 9(3): 477-486, 2018 Apr 25.
Artigo em Inglês | MEDLINE | ID: mdl-29633632

RESUMO

The use of probiotics to prevent or treat mucosal inflammation has been studied; however, the combined effect of probiotics and prebiotics is unclear. The aim of this study was to test whether oral administration of a synbiotic (Simbioflora®) preparation containing Lactobacillus paracasei, Lactobacillus rhamnosus, Lactobacillus acidophilus and Bifidobacterium lactis plus fructooligosaccharide could help control mucosal inflammation in experimental mucositis induced by 5-fluorouracil (5-FU). Male BALB/c mice were randomly divided into six groups: control (CTL), control + prebiotic (CTL+P), control + synbiotic (CTL+S), mucositis (MUC), mucositis + prebiotic (MUC+P), and mucositis + synbiotic (MUC+S). Mice from the CTL+S, MUC+S, CTL+P, and MUC+P groups received synbiotic or prebiotic daily by oral gavage for 13 days. Mice in the CTL and MUC groups received the same volume of saline. On day 11, mice in the MUC, MUC+P, and MUC+S groups received an intraperitoneal injection of 300 mg/kg 5-FU to induce mucositis. After 72 h, all mice were euthanised. Intestinal permeability, intestinal histology, and biochemical parameters were analysed. Group MUC showed a greater weight loss and increased intestinal permeability (0.020 counts per min [cpm]/g) compared to the CTL group (0.01 cpm/g) P<0.05. Both treatments attenuated weight loss compared to the MUC group. Nonetheless, the synbiotic caused a greater reduction in intestinal permeability (0.012 cpm/g) compared to the MUC (0.020 cpm/g) and MUC+P (0.016 cpm/g) groups P<0.05. Mice in groups MUC+P and MUC+S displayed significant recovery of lesions and maintenance of the mucus layer. There were no differences in the short-chain fatty acid concentrations in the faeces between the MUC and CTL groups (P>0.05). Increased acetate and propionate concentrations were evidenced in the faeces of the MUC+P and MUC+S groups. Only the synbiotic treatment increased the butyrate concentration (P<0.05). The results indicate that administration of synbiotic can decrease mucosal damage caused by mucositis.


Assuntos
Mucosite/prevenção & controle , Simbióticos/administração & dosagem , Administração Oral , Animais , Bifidobacterium animalis/crescimento & desenvolvimento , Bifidobacterium animalis/metabolismo , Peso Corporal , Ácidos Graxos Voláteis/análise , Fezes/química , Fluoruracila/administração & dosagem , Fluoruracila/toxicidade , Trato Gastrointestinal/patologia , Lactobacillus/crescimento & desenvolvimento , Lactobacillus/metabolismo , Camundongos Endogâmicos BALB C , Mucosite/induzido quimicamente , Oligossacarídeos/administração & dosagem , Oligossacarídeos/metabolismo , Resultado do Tratamento
10.
Ultrason Sonochem ; 38: 256-270, 2017 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-28633825

RESUMO

Copper tungstate (CuWO4) crystals were synthesized by the sonochemistry (SC) method, and then, heat treated in a conventional furnace at different temperatures for 1h. The structural evolution, growth mechanism and photoluminescence (PL) properties of these crystals were thoroughly investigated. X-ray diffraction patterns, micro-Raman spectra and Fourier transformed infrared spectra indicated that crystals heat treated and 100°C and 200°C have water molecules in their lattice (copper tungstate dihydrate (CuWO4·2H2O) with monoclinic structure), when the crystals are calcinated at 300°C have the presence of two phase (CuWO4·2H2O and CuWO4), while the others heat treated at 400°C and 500°C have a single CuWO4 triclinic structure. Field emission scanning electron microscopy revealed a change in the morphological features of these crystals with the increase of the heat treatment temperature. Transmission electron microscopy (TEM), high resolution-TEM images and selected area electron diffraction were employed to examine the shape, size and structure of these crystals. Ultraviolet-Visible spectra evidenced a decrease of band gap values with the increase of the temperature, which were correlated with the reduction of intermediary energy levels within the band gap. The intense photoluminescence (PL) emission was detected for the sample heat treat at 300°C for 1h, which have a mixture of CuWO4·2H2O and CuWO4 phases. Therefore, there is a synergic effect between the intermediary energy levels arising from these two phases during the electronic transitions responsible for PL emissions.

11.
Genetica ; 145(1): 19-25, 2017 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-28160168

RESUMO

Cystic fibrosis (CF) is a common autosomal recessive disorder, being the p.F508del the most frequent mutation. Also, a nearby restriction fragment length polymorphism (RFLP) named XK (KM19 and XV2C) is non-randomly associated with specific CF alleles. Our aim was to analyze the occurrence of the p.F508del mutation and XK haplotypes in Afro-Brazilians CF patients and controls, since these data is available for the other two main ethnic groups found in Brazil (Euro-Brazilians and Brazilian Amerindians), contributing for the whole comprehension of these haplotypes in the Brazilian population. A total of 103 patients and 54 controls were studied. PCR and PCR-RFLP methodologies were used to identify the presence of the p.F508del and the XK haplotype in the subjects. The combined data show that 84.2% of p.F508del mutation is associated with haplotype B and only 15.8% with haplotype A; no other haplotypes were found to be associated with this mutation. Our data suggest that the occurrence of p.F508del mutation and haplotype B in Afro-Brazilian patients occurs probably due to admixture with Euro-descendants. Therefore this mutation and haplotype could be used as a admixture marker.


Assuntos
Regulador de Condutância Transmembrana em Fibrose Cística/genética , Fibrose Cística/genética , Etnicidade/genética , Haplótipos , Mutação , Alelos , Brasil , Estudos de Casos e Controles , Frequência do Gene , Genética Populacional , Humanos , Masculino
12.
Benef Microbes ; 6(3): 277-86, 2015.
Artigo em Inglês | MEDLINE | ID: mdl-25391346

RESUMO

Inflammatory bowel diseases (IBD) are chronic inflammatory conditions, characterised by remissions and relapses episodes, whose main manifestations are ulcerative colitis and Crohn's disease. Ulcerative colitis (UC), one of the main forms of IBD, has as standard treatment the use of corticosteroids and anti-inflammatory drugs. The use of antibiotics has been also reported, but the possible adverse effects, such as disturbance of the indigenous microbiota or resistance induction, should be taken into consideration, and thus the use of probiotics emerges as a possible alternative option of treatment. In this study, the oral administration of Bifidobacterium longum subsp. infantis BB-02 was evaluated as a preventive strategy for acute experimental UC induced in female BALB/c mice by ingestion of 3.5% dextran sulphate sodium in drinking water during 7 days. During this time, the daily disease activity index was evaluated, and on the seventh day the animals were euthanised to collect intestines and liver for analysis. Treatment with the probiotic resulted in clinical improvement of the animals. The histological and morphometric analyses showed a reduction of lesions and oedema in the gut, but there was no increase in the production of mucin. The dosage of secretory immunoglobulin A was significantly higher in the colitis group and reduced in the group treated with the probiotic. There was also a reduction in the inflammation of the colon, as demonstrated by a decrease in neutrophils infiltration, and KC/CXCL-1 levels. The intestinal permeability, which is typically increased during the onset of IBD, was also reduced by treatment with probiotic. Based on these data, it can be concluded that the bacterium B. infantis BB-02 has a probiotic potential for the attenuation of UC, but further studies should be conducted to verify the mechanism of protective action of the bacterium.


Assuntos
Bifidobacterium/fisiologia , Doenças Inflamatórias Intestinais/tratamento farmacológico , Probióticos/administração & dosagem , Animais , Modelos Animais de Doenças , Feminino , Humanos , Imunoglobulina A/imunologia , Doenças Inflamatórias Intestinais/imunologia , Doenças Inflamatórias Intestinais/microbiologia , Camundongos , Camundongos Endogâmicos BALB C
13.
J Dairy Sci ; 96(12): 7442-53, 2013.
Artigo em Inglês | MEDLINE | ID: mdl-24140324

RESUMO

This study aimed to assess and compare the nutritional, technological, and sensory characteristics of Minas fresh cheese made with goat milk, cow milk, or a mixture of the two stored in cold conditions for 21d. The yield and centesimal composition of the cheeses were not affected by the type of milk used in their preparation. Reductions were observed in the moisture content, pH, proteolysis index, and instrumental hardness; moreover, increases were observed in the syneresis, acidity index, and depth of proteolysis index in all cheeses. The percentages of caprylic, capric, oleic, and linoleic fatty acids were higher in goat milk cheese and cheese made with a mixture of goat and cow milk compared with cow milk cheese, and a sensory evaluation revealed differences in color, flavor, and aroma between the cheeses. The preparation of Minas fresh cheese with a mixture of goat and cow milk can be a viable alternative for dairy products in the market that can be characterized as high-quality products that meet consumer demands.


Assuntos
Queijo/análise , Queijo/normas , Indústria de Laticínios/métodos , Leite/química , Valor Nutritivo , Animais , Bovinos , Cor , Indústria de Laticínios/normas , Ácidos Graxos/análise , Feminino , Cabras , Dureza , Concentração de Íons de Hidrogênio , Proteólise , Água/análise
14.
Braz J Microbiol ; 44(1): 29-35, 2013.
Artigo em Inglês | MEDLINE | ID: mdl-24159280

RESUMO

This study evaluated the influence of the phenolic compounds carvacrol (CAR) and thymol (THY) on some physiological characteristics and on the modulation of the secretion of some staphylococcal virulence factors, that is, coagulase and enterotoxin. This study also investigated possible mechanisms for the establishment of the anti-staphylococcal activity of these compounds. Sublethal concentrations (0.3 and 0.15 µL/mL) of CAR and THY inhibited the activity of the enzymes coagulase and lipase and led to a decrease in salt tolerance. At the tested sublethal concentrations, both CAR and THY led to a total suppression of enterotoxin production. The loss of a 260-nm-absorbing material and an efflux of potassium ions occurred immediately after the addition of CAR and THY at 0.6 and 1.2 µL/mL and increased up to 120 min of exposure. Electron microscopy of cells exposed to CAR and THY (0.6 µL/mL) revealed that individual cells appeared to be deformed, with projections of cellular material. The observations of leakage of cellular material and an altered cell surface suggest that gross damage to a cell's cytoplasmic membrane, which results in a disruption in protein secretion, could be responsible for the anti-staphylococcal properties of CAR and THY.

15.
Braz. j. microbiol ; 44(1): 29-36, 2013. ilus, tab
Artigo em Inglês | LILACS | ID: lil-676882

RESUMO

This study evaluated the influence of the phenolic compounds carvacrol (CAR) and thymol (THY) on some physiological characteristics and on the modulation of the secretion of some staphylococcal virulence factors, that is, coagulase and enterotoxin. This study also investigated possible mechanisms for the establishment of the anti-staphylococcal activity of these compounds. Sublethal concentrations (0.3 and 0.15 µL/mL) of CAR and THY inhibited the activity of the enzymes coagulase and lipase and led to a decrease in salt tolerance. At the tested sublethal concentrations, both CAR and THY led to a total suppression of enterotoxin production. The loss of a 260-nm-absorbing material and an efflux of potassium ions occurred immediately after the addition of CAR and THY at 0.6 and 1.2 µL/mL and increased up to 120 min of exposure. Electron microscopy of cells exposed to CAR and THY (0.6 µL/mL) revealed that individual cells appeared to be deformed, with projections of cellular material. The observations of leakage of cellular material and an altered cell surface suggest that gross damage to a cell's cytoplasmic membrane, which results in a disruption in protein secretion, could be responsible for the anti-staphylococcal properties of CAR and THY.


Assuntos
Humanos , Secreções Corporais , Coagulase/análise , Coagulase/isolamento & purificação , Compostos Fenólicos/análise , Ativação Enzimática , Enterotoxinas/isolamento & purificação , Lipase/análise , Microscopia Eletrônica , Staphylococcus aureus/enzimologia , Staphylococcus aureus/isolamento & purificação , Amostras de Alimentos , Métodos , Virulência
16.
J Med Microbiol ; 61(Pt 9): 1194-1207, 2012 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-22580913

RESUMO

Recently, much attention has been given to the use of probiotics as an adjuvant for the prevention or treatment of gastrointestinal pathology. The great advantage of therapy with probiotics is that they have few side effects such as selection of resistant bacteria or disturbance of the intestinal microbiota, which occur when antibiotics are used. Adhesion of pathogenic bacteria onto the surface of probiotics instead of onto intestinal receptors could explain part of the probiotic effect. Thus, this study evaluated the adhesion of pathogenic bacteria onto the cell wall of Saccharomyces boulardii and Saccharomyces cerevisiae strains UFMG 905, W303 and BY4741. To understand the mechanism of adhesion of pathogens to yeast, cell-wall mutants of the parental strain of Saccharomyces cerevisiae BY4741 were used because of the difficulty of mutating polyploid yeast, as is the case for Saccharomyces cerevisiae and Saccharomyces boulardii. The tests of adhesion showed that, among 11 enteropathogenic bacteria tested, only Escherichia coli, Salmonella Typhimurium and Salmonella Typhi adhered to the surface of Saccharomyces boulardii, Saccharomyces cerevisiae UFMG 905 and Saccharomyces cerevisiae BY4741. The presence of mannose, and to some extent bile salts, inhibited this adhesion, which was not dependent on yeast viability. Among 44 cell-wall mutants of Saccharomyces cerevisiae BY4741, five lost the ability to fix the bacteria. Electron microscopy showed that the phenomenon of yeast-bacteria adhesion occurred both in vitro and in vivo (in the digestive tract of dixenic mice). In conclusion, some pathogenic bacteria were captured on the surface of Saccharomyces boulardii, Saccharomyces cerevisiae UFMG 905 and Saccharomyces cerevisiae BY4741, thus preventing their adhesion to specific receptors on the intestinal epithelium and their subsequent invasion of the host.


Assuntos
Aderência Bacteriana/fisiologia , Parede Celular/microbiologia , Escherichia coli/fisiologia , Probióticos/metabolismo , Saccharomyces/fisiologia , Salmonella typhimurium/fisiologia , Animais , Humanos , Intestinos/microbiologia , Camundongos , Camundongos Endogâmicos NOD , Saccharomyces/classificação
17.
Fitoterapia ; 76(2): 247-9, 2005 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-15752642

RESUMO

The antifungal activity of Eugenia cariophyllata essential oil and eugenol, its major constituent, on fungal strains isolated from onychomycosis was evaluated. The natural products presented prominent antifungal action with MIC of 1% and 4%, respectively.


Assuntos
Antifúngicos/farmacologia , Eugenol/farmacologia , Fungos Mitospóricos/efeitos dos fármacos , Fitoterapia , Óleos de Plantas/farmacologia , Syzygium , Antifúngicos/administração & dosagem , Antifúngicos/uso terapêutico , Eugenol/administração & dosagem , Eugenol/uso terapêutico , Humanos , Testes de Sensibilidade Microbiana , Onicomicose/microbiologia , Óleos de Plantas/administração & dosagem , Óleos de Plantas/uso terapêutico
18.
Rev. bras. anal. clin ; 35(4): 191-194, 2003. ilus, tab
Artigo em Português | LILACS | ID: lil-497505

RESUMO

Tinea capitis é uma micose produzida pelos dermatófitos dos gêneros Trichophyton e Microsporum que parasitam os pelos e pele do couro cabeludo.Tendo em vista a necessidade de obter princípios ativos para uma possível aplicação prática no tratamento de infecções, o estudo de produtos de origem vegeral ou sintética, com atividade antifúngica vem recebendo grande ênfase. Neste trabalho foi feita avaliação da atividade antifùngica de cinco maleimidas: 3,4 dicloro N fenil etil maleimida, 3,4 dicloro N benzil maleimida, 3,4 dicloro N fenil butil maleimida, 3,4 dicloro N fenil propil maleimida e 3,4 dicloro N fenil maleimida. Tais substâncias foram testadas in vitro através do método de difusão em meio sólido,contra 20 cepas de dermatófitos, isolados de amostras clínicas de pacientes portadores de Tinea capitis. Os resultados destacaram a atividade antifúngica apresentada pelo composto 3,4 dicloro N fenil etil maleimida, inibindo 100% das cepas testadas na concentração de 200 mg/ml, e 3,4 dicloro N fenil propil maleimida que apresentou uma CIM de 6,3mg/ml.


Assuntos
Humanos , Arthrodermataceae , Antifúngicos , Maleimidas , Tinha do Couro Cabeludo
19.
JSLS ; 5(2): 159-65, 2001.
Artigo em Inglês | MEDLINE | ID: mdl-11394429

RESUMO

It has been shown that a video-laparoscopic approach is the preferred method for treatment of cholecystitis. However, when we consider acute cholecystitis, many questions must be answered. The aim of this study is to compare video-laparoscopic and conventional surgery in the management of acute cholecystitis.


Assuntos
Colecistectomia Laparoscópica , Colecistite/cirurgia , Cirurgia Vídeoassistida , Doença Aguda , Adolescente , Adulto , Idoso , Idoso de 80 Anos ou mais , Criança , Colecistectomia , Colecistectomia Laparoscópica/métodos , Humanos , Pessoa de Meia-Idade , Fatores de Risco , Cirurgia Vídeoassistida/métodos
20.
Protein Expr Purif ; 19(1): 41-7, 2000 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-10833388

RESUMO

Snake venoms are rich sources of proteases that strongly affect the vascular system, by promoting blood coagulation, hemorrhage, and fibrinolysis. Hemorrhagic activity is mostly due to the enzymatic action of metalloproteases on capillary basement membrane components, such as collagen IV, laminin, and fibronectin. A few low-molecular-weight snake venom metalloproteases (svMP) have been described as being devoid of hemorrhagic activity, but they have strong direct-acting fibrinolytic activity that could be very helpful in thrombosis therapy. We have developed an expression system for production of a recombinant svMP from a cDNA (ACLPREF) coding for a small metalloprotease (ACLF) with three disulfide bonds from an Agkistrodon contortrix laticinctus (broad-banded copperhead) venom gland cDNA library. The mature protein-coding region was amplified by PCR and subcloned into the pET28a vector, and the resulting plasmid was used to transform BL21(DE3) Escherichia coli cells. Culture of the transformants at either 37 or 20 degrees C led to the overexpression of an insoluble and inactive 30-kDa protein after 1.0 mM IPTG induction. The expressed protein (rACLF) was recovered from inclusion bodies with 6 M buffered urea solution and purified on a nickel-Sepharose column followed by gel filtration chromatography, both under denaturing conditions. After treatment with dithiothreitol, protein refolding was performed by gradual removal of the denaturing agent by dialysis. The refolded recombinant protein was active in fibrin-agarose plates. The purified protein achieved a conformation similar to that of the native enzyme as judged by circular dichroism analysis.


Assuntos
Agkistrodon/metabolismo , Venenos de Crotalídeos/química , Metaloendopeptidases/química , Dobramento de Proteína , Animais , Cromatografia em Agarose , Cromatografia em Gel , Dicroísmo Circular , Dissulfetos , Ditiotreitol , Escherichia coli/genética , Escherichia coli/metabolismo , Fibrinolíticos/química , Fibrinolíticos/isolamento & purificação , Fibrinolíticos/metabolismo , Hemorragia/induzido quimicamente , Corpos de Inclusão/metabolismo , Metaloendopeptidases/isolamento & purificação , Metaloendopeptidases/metabolismo , Camundongos , Estrutura Secundária de Proteína , Proteínas Recombinantes/química , Proteínas Recombinantes/isolamento & purificação , Proteínas Recombinantes/metabolismo
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