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1.
Food Chem ; 304: 125415, 2020 Jan 30.
Artigo em Inglês | MEDLINE | ID: mdl-31479995

RESUMO

The aim of our study was to characterize the proteolytic activity of 170 Lactobacillus strains isolated from traditional Mongolian dairy products (yogurt and fermented milk), and to investigate their capacity to generate bioactive peptides during milk fermentation. All isolates were screened for proteolytic activity using skim milk agar-well diffusion test. Fifteen strains (9 Lactobacillus helveticus and 6 Lactobacillus delbrueckii subsp. bulgaricus) were then selected and further evaluated using an original strategy based on multiparametric analysis, taking into account growth rate, acidification capacity, proteolytic activity, cell envelope associated peptidase (CEP) profile and LC-MS/MS analysis of peptides. All parameters were analyzed using principal component analysis (PCA). Results showed that strain growth and acidification correlate with peptide production and that Mongolian L. helveticus strains differ from Western strains in terms of CEP distribution. The PCA revealed that CEP profiles are major determinants of ß-casein hydrolysis patterns. Strains with distinctive proteolytic activities were identified.

2.
Chemosphere ; 220: 505-513, 2019 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-30594803

RESUMO

We evaluated the acute toxicities of metals cadmium (Cd), copper (Cu) and nickel (Ni) to a widely-distributed copepod Eurytemora affinis isolated from the Seine estuary. Both sexes of adult E. affinis were exposed separately to the three metals at concentration gradients to determine its 50% lethal concentration (LC50). After 4 days of exposure, both males and females showed a higher sensitivity to Cu (male LC50: 25.0 µg.L-1 and female LC50: 38.0 µg.L-1) than to Ni (male LC50: 90.0 µg.L-1 and female 161.0 µg.L-1) and Cd (male LC50: 127.8 µg.L-1 and female LC50: 90.0 µg.L-1). To assess for the first time, the extend of metal bioaccumulation and its effect at population scale, late stages (>200 µm) were collected and exposed to each metal at the concentration of 1/3 LC50, and to their mixture during 144 h without feeding. The Cd concentration consistently increased with time until the end of the experiment, whereas the Ni and Cu concentrations reached a plateau after 24 h and 72 h exposure, respectively. The results revealed that the copepods could accumulate Cu faster than Ni and Cd either in the treatment alone (0.58 L g-1.d-1) or in the three-metal mixture (0.72 L g-1.d-1) after 50% of exposure time (72 h). The number of individuals decreased in copepod populations except for the Cd treatment, where the number of nauplii increased. In addition, all treatments of metal exposure negatively affected bacterial densities in the copepod cultures, where the Cu treatment showed a negative remarkable effect compared with Cd and Ni treatment did.


Assuntos
Cádmio/toxicidade , Copépodes/metabolismo , Cobre/toxicidade , Níquel/toxicidade , Poluentes Químicos da Água/toxicidade , Animais , Copépodes/efeitos dos fármacos , Estuários
3.
Front Microbiol ; 9: 2354, 2018.
Artigo em Inglês | MEDLINE | ID: mdl-30386307

RESUMO

To compensate for their amino acid auxotrophy, lactobacilli have developed the ability to hydrolyze proteins present in their environment. This proteolytic activity not only generates the free amino acids needed by the bacteria, but also a large variety of peptides, some of which are endowed with biological activities. These so-called "bioactive peptides" (BAPs) are interesting from a nutrition and healthcare perspective. The use of lactic acid bacteria (LAB) such as lactobacilli is an effective strategy for production and valorization of new BAPs. The proteolytic activity of lactobacilli is exerted in a strain- and species-dependent manner: each species exhibits different proteinase content, leading to a large variety of proteolytic activities. This underlines the high potential of Lactobacillus strains to produce novel hydrolysates and BAPs of major interest. This review aims at discussing the potential of different Lactobacillus species to release BAPs from fermentation media and processes. Strategies used for peptide production are presented. Additionally, we propose a methodology to select the most promising Lactobacillus strains as sources of BAPs. This methodology combines conventional approaches and in silico analyses.

4.
Artigo em Inglês | MEDLINE | ID: mdl-30229513

RESUMO

Here we show that Bacillus pumilus ICVB403 recently isolated from copepod eggs is able to produce, after 48-72 h of growth in Landy medium, extracellular inhibitory compounds, which are active against Staphylococcus aureus ATCC 25923, methicillin-resistant S. aureus (MRSA) ATCC 43300, MRSA-S1, Staphylococcus epidermidis 11EMB, Staphylococcus warneri 27EMB, and Staphylococcus hominis 13EMB. Moreover, these extracellular inhibitory compound(s) were able to potentiate erythromycin against the aforementioned staphylococci. The minimum inhibitory concentration (MIC) of erythromycin was reduced from 32 µg/mL to 8 µg/mL for MRSA ATCC 43300 and MRSA SA-1 strains, and from 32-64 µg/mL to 4 µg/mL for S. epidermidis 11EMB and S. hominis 13EMB strains.The genome sequencing and analysis of B. pumilus ICVB403 unveiled 3.666.195 nucleotides contained in 22 contigs with a G + C ratio of 42.0%, 3.826 coding sequences, and 73 RNAs. In silico analysis guided identification of two putative genes coding for synthesis of surfactin A, a lipopeptide with 7 amino acids, and for a circular bacteriocin belonging to the circularin A/uberolysin family, respectively.

5.
J Agric Food Chem ; 66(25): 6439-6449, 2018 Jun 27.
Artigo em Inglês | MEDLINE | ID: mdl-29873488

RESUMO

The objectives of this work are to address the prebiotic effects of chicory ( Cichorium intybus) together with its possible role in appetite control. We compared nine chicory genotypes in order to determine if variations in the content of metabolites in the roasted roots would lead to modifications in release of satiety hormones and in composition of gut microbiota. To this aim, a 5-week dietary-intervention study was achieved using mice fed with distinct chicory-based preparations. A 16S rRNA gene-based metagenetic analysis of fecal microbiota was performed. In vitro gastrointestinal digestions were performed in order to study the effect of chicory intestinal digests on gut hormone regulation in enteroendocrine cells. Firmicutes/Bacteroidetes ratio and gut bacterial groups, such as Alloprevotella, Blautia, Alistipes, and Oscillibacter, were found to be modulated by chicory. On the other hand, CCK and GLP-1 satiety hormones were demonstrated to be significantly increased by chicory in vitro.


Assuntos
Regulação do Apetite/efeitos dos fármacos , Chicória/química , Extratos Vegetais/farmacologia , Prebióticos/análise , Animais , Bactérias/classificação , Bactérias/genética , Bactérias/isolamento & purificação , Chicória/genética , Chicória/metabolismo , Digestão/efeitos dos fármacos , Microbioma Gastrointestinal/efeitos dos fármacos , Trato Gastrointestinal/metabolismo , Trato Gastrointestinal/microbiologia , Camundongos , Extratos Vegetais/metabolismo
6.
Artigo em Inglês | MEDLINE | ID: mdl-29692758

RESUMO

A qualitative study is presented, where the main question was whether food-derived hemorphins, i.e., originating from digested alimentary hemoglobin, could pass the intestinal barrier and/or the blood-brain barrier (BBB). Once absorbed, hemorphins are opioid receptor (OR) ligands that may interact with peripheral and central OR and have effects on food intake and energy balance regulation. LLVV-YPWT (LLVV-H4), LVV-H4, VV-H4, VV-YPWTQRF (VV-H7), and VV-H7 hemorphins that were previously identified in the 120 min digest resulting from the simulated gastrointestinal digestion of hemoglobin have been synthesized to be tested in in vitro models of passage of IB and BBB. LC-MS/MS analyses yielded that all hemorphins, except the LLVV-H4 sequence, were able to cross intact the human intestinal epithelium model with Caco-2 cells within 5-60 min when applied at 5 mM. Moreover, all hemorphins crossed intact the human BBB model with brain-like endothelial cells (BLEC) within 30 min when applied at 100 µM. Fragments of these hemorphins were also detected, especially the YPWT common tetrapeptide that retains OR-binding capacity. A cAMP assay performed in Caco-2 cells indicates that tested hemorphins behave as OR agonists in these cells by reducing cAMP production. We further provide preliminary results regarding the effects of hemorphins on tight junction proteins, specifically here the claudin-4 that is involved in paracellular permeability. All hemorphins at 100 µM, except the LLVV-H4 peptide, significantly decreased claudin-4 mRNA levels in the Caco-2 intestinal model. This in vitro study is a first step toward demonstrating food-derived hemorphins bioavailability which is in line with the growing body of evidence supporting physiological functions for food-derived peptides.

7.
Probiotics Antimicrob Proteins ; 10(3): 456-465, 2018 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-29168155

RESUMO

This study aimed at comparing the genome of Enterococcus faecalis B3A-B3B, a bacteriocinogenic strain recently isolated from a healthy Iraqi infant to those of Enterococci of clinical and beneficial grades. The putative genes gelE, cpd, efaAfm, ccf, agg, and cob coding for virulence factors were detected in B3A-B3B strain, which meanwhile resulted to be non-cytotoxic, non-hemolytic, devoid of inflammatory effects, and sensitive to most of the antibiotics tested except for clindamycin and trimethoprim, which resistance is usually ascribed to intrinsic nature. B3A-B3B strain was remarkable for its hydrophobicity, auto-aggregation, adhesion to human Caco-2 cells, and survival in simulated gastrointestinal conditions, and cholesterol assimilation fulfilling therefore key beneficial attributes.

8.
Front Microbiol ; 8: 1919, 2017.
Artigo em Inglês | MEDLINE | ID: mdl-29085344

RESUMO

Copepods represent a major source of food for many aquatic species of commercial interest for aquaculture such as mysis shrimp and early stages of fishes. For the purpose of this study, the culturable mesophilic bacterial flora colonizing Acartia tonsa copepod eggs was isolated and identified. A total of 175 isolates were characterized based on their morphological and biochemical traits. The majority of these isolates (70%) were Gram-negative bacteria. Matrix-assisted laser desorption/ionization-time of flight-mass spectrometry (MALDI-TOF-MS) was used for rapid identification of bacterial isolates. Here, 58% of isolates were successfully identified at the genus level and among them, 54% were identified at the species level. These isolates belong to 12 different genera and 29 species. Five strains, identified as Bacillus pumilus, named 18 COPS, 35A COPS, 35R COPS, 38 COPS, and 40A COPS, showed strong antagonisms against several potential fish pathogens including Vibrio alginolyticus, V. anguillarum, Listeria monocytogenes, and Staphylococcus aureus. Furthermore, using a differential approach, we show that the antimicrobial activity of the 35R COPS strain is linked primarily to the production of antimicrobial compounds of the amicoumacin family, as demonstrated by the specific UV-absorbance and the MS/MS fragmentation patterns of these compounds.

9.
Artigo em Inglês | MEDLINE | ID: mdl-28484425

RESUMO

The gut plays a central role in energy homeostasis. Food intake regulation strongly relies on the gut-brain axis, and numerous studies have pointed out the significant role played by gut hormones released from enteroendocrine cells. It is well known that digestive products of dietary protein possess a high satiating effect compared to carbohydrates and fat. Nevertheless, the processes occurring in the gut during protein digestion involved in the short-term regulation of food intake are still not totally unraveled. This review provides a concise overview of the current data concerning the implication of food-derived peptides in the peripheral regulation of food intake with a focus on the gut hormones cholecystokinin and glucagon-like peptide 1 regulation and the relationship with some aspects of glucose homeostasis.

10.
Food Res Int ; 92: 113-118, 2017 02.
Artigo em Inglês | MEDLINE | ID: mdl-28290288

RESUMO

Dietary proteins have recently been investigated as a new source of DPP-IV inhibitory peptides with limited side effects and promising applications. Numerous studies have highlighted and identified peptide sequences able to inhibit DPP-IV activity in vitro, mostly from milk proteins. However, the correlation to in vivo studies remains scarce because standard in vitro assays with purified enzyme do not accurately simulate key factors impacting peptide bioactivity such as intestinal and brush border enzymes or cellular permeability. Therefore, a DPP-IV activity inhibition assay is here proposed using non differentiated confluent Caco-2 cells to rapidly assess food-derived peptide inhibitory potential in approaching intestinal conditions. DPP-IV gene expression was first checked and specific DPP-IV substrate was used to implement the assay. Using a specific DPP-IV inhibitor confirmed that non differentiated Caco-2 cells express measurable DPPIV activity. This in situ assay was then applied to digests which already demonstrated a DPP-IV inhibitory potential with a standard assay using purified enzyme. Bovine hemoglobin and cuttlefish hydrolysate digests from simulated gastrointestinal digestion exerted a dose response inhibition on DPP-IV activity but displayed different inhibitory potentials.

11.
Res Microbiol ; 168(3): 244-254, 2017 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-28093322

RESUMO

Sixty-seven (67) lactic acid bacteria (LAB) isolates belonging to Lactobacillus genus were isolated from human feces and tested for their auto-aggregation and cell surface hydrophobicity in order to establish their adhesion capabilities, a prerequisite for probiotic selection. Strains with the upmost auto-aggregation and cell surface hydrophobicity scores were identified by MALDI-TOF spectrometry and 16S rDNA sequencing as Lactobacillus plantarum (p25lb1 and p98lb1) and Lactobacillus salivarius (p85lb1 and p104lb1). These strains were also able to adhere to human epithelial colorectal adenocarcinoma Caco-2 cells, with percentages ranging from 4.68 to 9.59%. They displayed good survival under conditions mimicking the gastrointestinal environment and remarkably impeded adhesion and invasion of human Caco-2 by Listeria monocytogenes and Enteropathogenic Escherichia coli. It should also be noted that Lb. plantarum p98lb1 was able to reduce in vitro cholesterol concentration by about 32%, offering an additional health attribute.


Assuntos
Fezes/microbiologia , Lactobacillus plantarum/isolamento & purificação , Lactobacillus salivarius/isolamento & purificação , Probióticos , Adulto , Argélia , Aderência Bacteriana , Ácidos e Sais Biliares , Células CACO-2 , Colesterol/análise , Meios de Cultura/química , Humanos , Interações Hidrofóbicas e Hidrofílicas , Lactente , Lactobacillus plantarum/genética , Lactobacillus plantarum/fisiologia , Lactobacillus salivarius/genética , Lactobacillus salivarius/fisiologia , Viabilidade Microbiana , RNA Ribossômico 16S/genética , Análise de Sequência de DNA
12.
Int J Antimicrob Agents ; 49(3): 282-289, 2017 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-28104423

RESUMO

Enterococcus faecalis 14, a strain previously isolated from meconium, displayed activity against four Clostridium perfringens isolates when co-cultured on agar plates. The anti-Clostridium activity was ascribed to the production of enterocin DD14, which was subsequently purified. The minimum inhibitory concentration (MIC) of enterocin DD14 against one collection strain and one clinical C. perfringens strain was determined at 50 µg/mL. Furthermore, using the intestinal epithelial cell line IPEC-1, it was shown that E. faecalis 14 was not cytotoxic after 24 h of contact, and no cytotoxicity was observed when IPEC-1 cells were incubated with pure enterocin DD14 for 4 h. Enterocin DD14 was characterised using mass spectrometry and was shown to consist of two small proteins of 5200.74 Da and 5206.41 Da, respectively. The two peptides (DD14A and DD14B) have highly similar amino acid sequences and no signal peptide, which classifies enterocin DD14 as a class IIb leaderless two-peptide bacteriocin. The genes encoding DD14A and DD14B were sequenced and were shown to be 100% identical to other previously described enterocins MR10A and MR10B, in contrast to the producing strains, which are different. Consequently, the present in vitro study supports the potential of this E. faecalis 14 strain and/or its purified enterocin DD14 as putative anti-C. perfringens compounds in chickens.


Assuntos
Antibacterianos/farmacologia , Clostridium perfringens/efeitos dos fármacos , Peptídeos/farmacologia , Animais , Antibacterianos/isolamento & purificação , Hidrocarbonetos Aromáticos com Pontes/química , Hidrocarbonetos Aromáticos com Pontes/isolamento & purificação , Hidrocarbonetos Aromáticos com Pontes/farmacologia , Linhagem Celular , Sobrevivência Celular , Enterococcus faecalis/metabolismo , Células Epiteliais/efeitos dos fármacos , Células Epiteliais/fisiologia , Testes de Sensibilidade Microbiana , Peso Molecular , Peptídeos/química , Peptídeos/isolamento & purificação , Análise de Sequência de DNA , Homologia de Sequência , Suínos
13.
Electrophoresis ; 37(13): 1814-22, 2016 07.
Artigo em Inglês | MEDLINE | ID: mdl-26990205

RESUMO

Consumers and governments have become aware how the daily diet may affect the human health. All proteins from both plant and animal origins are potential sources of a wide range of bioactive peptides and the large majority of those display health-promoting effects. In the meat production food chain, the slaughterhouse blood is an inevitable co-product and, today, the blood proteins remain underexploited despite their bioactive potentiality. Through a comparative food peptidomics approach we illustrate the impact of resolving power, accuracy, sensitivity, and acquisition speed of low-resolution (LR)- and high-resolution (HR)-LC-ESI-MS/MS on the obtained peptide mappings and discuss the limitations of MS-based peptidomics. From in vitro gastrointestinal digestions of partially purified bovine hemoglobin, we have established the peptide maps of each hemoglobin chain. LR technique (normal bore C18 LC-LR-ESI-MS/MS) allows us to identify without ambiguity 75 unique peptides while the HR approach (nano bore C18 LC-HR-ESI-MS/MS) unambiguously identify more than 950 unique peptides (post-translational modifications included). Herein, the food peptidomics approach using the most performant separation methods and mass spectrometers with high-resolution capabilities appears as a promising source of information to assess the health potentiality of proteins.


Assuntos
Cromatografia Líquida/métodos , Digestão , Análise de Alimentos , Hemoglobinas/metabolismo , Peptídeos/metabolismo , Proteômica , Espectrometria de Massas em Tandem/métodos , Animais , Bovinos , Técnicas In Vitro , Mapeamento de Peptídeos
14.
Food Res Int ; 89(Pt 1): 382-390, 2016 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-28460928

RESUMO

Dietary proteins have been reported to induce a strong feeling of satiety that has been partially explained by gut hormone level increase. Up to date, various protein hydrolysates have demonstrated in vitro and in vivo their potential to stimulate gut hormone secretion related to food intake decrease and their mechanisms of action have just started to be resolved. In this context, this study aimed at identifying new peptide sequences involved in gut hormone secretion released by protein in vitro gastrointestinal digestion. Targeted gut hormones were Cholecystokinin (CCK) and Glucagon-Like Peptide 1 (GLP-1). The activity of DPP-IV was also considered as it strongly modulates GLP-1 action. In a previous study, simulated digestion of dietary protein has generated hydrolysates with enhancing effect on CCK and GLP-1 secretion in STC-1 cells as well as DPP-IV inhibitory properties. Successive purification steps were performed to isolate peptide fractions involved in these bioactivities whose sequence was determined by LC-MS-MS. Three peptide sequences ANVST, TKAVEH and KAAVT were pointed out for their stimulating effects on GLP-1 secretion. The sequence VAAA was isolated for its DPP-IV inhibitory properties. Two peptide groups were strongly involved in CCK release sharing a certain occurrence of aromatic amino acid residues.

15.
Arch Microbiol ; 198(1): 71-81, 2016 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-26404657

RESUMO

This study aimed at showing the yeast diversity in feces of Algerian infants, aged between 1 and 24 months, hospitalized at Bejaia hospital (northeast side of the country). Thus, 20 colonies with yeast characteristics were isolated and identified using biochemical (ID32C Api system) and molecular (sequencing of ITS1-5.8S-ITS2 region) methods. Almost all colonies isolated (19 strains) were identified as Candida spp., with predominance of Candida albicans species, and one strain was identified as Saccharomyces cerevisiae. Screening of strains with inhibitory activities unveiled the potential of Candida parapsilosis P48L1 and Candida albicans P51L1 to inhibit the growth of Escherichia coli ATCC 25922 and Staphylococcus aureus ATCC 25923. Further studies performed with these two Candida strains revealed their susceptibility to clinically used antifungal compounds and were then characterized for their cytotoxicity and hemolytic properties. On the other hand, Saccharomyces cerevisiae P9L1 isolated as well in this study was shown to be devoid of antagonism but resulted safe and overall usable as probiotic.


Assuntos
Biodiversidade , Fezes/microbiologia , Leveduras/isolamento & purificação , Leveduras/fisiologia , Argélia , Antifúngicos/farmacologia , Candida/efeitos dos fármacos , Candida/isolamento & purificação , Candida/fisiologia , Candida albicans/efeitos dos fármacos , Candida albicans/isolamento & purificação , Candida albicans/fisiologia , Escherichia coli/crescimento & desenvolvimento , Humanos , Lactente , Interações Microbianas , Saccharomyces cerevisiae/efeitos dos fármacos , Saccharomyces cerevisiae/isolamento & purificação , Saccharomyces cerevisiae/fisiologia , Leveduras/efeitos dos fármacos
16.
J Agric Food Chem ; 64(3): 663-70, 2016 Jan 27.
Artigo em Inglês | MEDLINE | ID: mdl-26671070

RESUMO

In shrimp, the development of postmortem melanosis resulting from phenoloxidase activities leads to important economic losses. Phenoloxidase enzymes include catechol oxidases, laccases, and tyrosinases, but hemocyanin is also capable of phenoloxidase activities. These activities have been explored in Penaeus monodon, using different substrates. Results highlighted that tyrosinase-specific substrates were little oxidized, whereas hydroquinone (laccase-specific substrate) was more highly oxidized than l-DOPA (nonspecific substrate) in the pereopods and pleopods. Global phenoloxidase activity, assayed with l-DOPA, did not appear thermally stable over time and probably resulted from phenoloxidase enzymes. Conversely, the laccase-like activity assayed with hydroquinone was thermally stable over time, reflecting the thermal stability of hemocyanin. Independently of the anatomical compartment, the temperature, or the substrate, the highest activities were assayed in the cuticular compartments. This study demonstrates the complexity of phenoloxidase activities in P. monodon, and the importance of considering all the activities, including laccase-like activities such as that of hemocyanin.


Assuntos
Hemocianinas/metabolismo , Lacase/metabolismo , Melaninas/metabolismo , Penaeidae/enzimologia , Animais , Estabilidade Enzimática , Hemocianinas/química , Lacase/química , Melaninas/química , Oxirredução , Penaeidae/metabolismo , Especificidade por Substrato
17.
Probiotics Antimicrob Proteins ; 7(4): 233-41, 2015 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-26459296

RESUMO

We studied here the yeast content of poultry feces, collected randomly from a French farm located in the north of the country. Thus, 81 yeast colonies were isolated and clustered into 22 distinct groups using the rep-PCR method. A single colony was taken from each group and identified using biochemical (ID 32C system) and molecular (sequencing of the D1/D2 domain of 26S rDNA and ITS1-5.8-ITS2 rDNA region) methods. Both methods led to the identification of Candida famata species. One isolate of C. famata strains, named strain Y5, was further studied for its cytotoxicity, adhesion, and surface properties, hemolytic activity, and its survival in simulated gastric and intestine environments. The data obtained advocate the probiotic potential of this isolate.


Assuntos
Candida/isolamento & purificação , Fezes/microbiologia , Aves Domésticas/microbiologia , Probióticos , Animais , Candida/classificação , Candida/fisiologia , França , Humanos
19.
Int J Food Microbiol ; 191: 116-24, 2014 Nov 17.
Artigo em Inglês | MEDLINE | ID: mdl-25261829

RESUMO

Two hundred and thirty individual clones of microorganisms were recovered from milk tanks and milking machine surfaces at two distinct farms (Bejaja City, Algeria). Of these clones, 130 were identified as lactic acid bacteria (LAB). In addition Escherichia coli, Salmonella, Staphylococcus aureus and Pseudomonas aeruginosa species were identified in the remaining 100 isolates-spoilage isolate. These isolates were assayed for ability to form biofilms. S. aureus, Lactobacillus brevis strains LB1F2, LB14F1 and LB15F1, and Lactobacillus pentosus strains LB2F2 and LB3F2 were identified as the best biofilm formers. Besides, these LAB isolates were able to produce proteinaceous substances with antagonism against the aforementioned spoilage isolates, when grown in MRS or TSB-YE media. During the screening, L. pentosus LB3F2 exhibited the highest antibacterial activity when grown in TSB-YE medium at 30 °C. Additionally, L. pentosus LB3F2 was able to strongly hamper the adhesion of S. aureus SA3 on abiotic surfaces as polystyrene and stainless steel slides. LAB isolates did not show any hemolytic activity and all of them were sensitive to different families of antibiotic tested. It should be pointed out that LB3F2 isolate was not cytotoxic on the intestinal cells but could stimulate their metabolic activity. This report unveiled the potential of LB1F2, LB14F1, LB15F1, LB2F2, and LB3F2 isolates to be used as natural barrier or competitive exclusion organism in the food processing sector as well as a positive biofilm forming bacteria.


Assuntos
Antibiose/fisiologia , Fenômenos Fisiológicos Bacterianos , Biofilmes , Lactobacillus/fisiologia , Aço Inoxidável , Animais , Antibacterianos/farmacologia , Bactérias/efeitos dos fármacos , Aderência Bacteriana , Linhagem Celular Tumoral , Indústria de Processamento de Alimentos/instrumentação , Indústria de Processamento de Alimentos/normas , Camundongos , Poliestirenos
20.
Peptides ; 48: 134-6, 2013 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-23954476

RESUMO

Apelin is an enteric peptide that exerts several digestive functions such as stimulation of cell proliferation and cholecystokinin (CCK) secretion. We investigated using murine enteroendocrine cell line (STC-1) and rats if apelin-13 stimulates both CCK and glucagon-like peptide 1 (GLP-1) secretions. We demonstrated that, in vitro and in vivo, apelin-13 increases the release of these two hormones in a dose-dependent manner. Present data suggest that apelin may modulate digestive functions, food intake behavior and glucose homoeostasis via apelin-induced release of enteric CCK but also through a new incretin-releasing activity on enteric GLP-1.


Assuntos
Colecistocinina/metabolismo , Sistema Digestório/efeitos dos fármacos , Peptídeo 1 Semelhante ao Glucagon/metabolismo , Peptídeos e Proteínas de Sinalização Intercelular/administração & dosagem , Animais , Linhagem Celular , Proliferação de Células/efeitos dos fármacos , Sistema Digestório/metabolismo , Ingestão de Alimentos/efeitos dos fármacos , Camundongos , Ratos
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