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1.
Front Microbiol ; 14: 1254692, 2023.
Artigo em Inglês | MEDLINE | ID: mdl-38107857

RESUMO

Introduction: Whole Genome Sequencing (WGS) implementation in food safety laboratories is a significant advancement in food pathogen control and outbreak tracking. However, the initial investment for acquiring next-generation sequencing platforms and the need for bioinformatic skills represented an obstacle for the widespread use of WGS. Long-reading technologies, such as the one developed by Oxford Nanopore Technologies, can be easily implemented with a minor initial investment and with simple protocols that can be performed with basic laboratory equipment. Methods: Herein, we report a simple MinION Galaxy-based workflow with analysis parameters that allow its implementation in food safety laboratories with limited computer resources and without previous knowledge in bioinformatics for rapid Salmonella serotyping, virulence, and identification of antimicrobial resistance genes. For that purpose, the single use Flongle flow cells, along with the MinION Mk1B for WGS, and the community-driven web-based analysis platform Galaxy for bioinformatic analysis was used. Three strains belonging to three different serotypes, monophasic S. Typhimurium, S. Grancanaria, and S. Senftenberg, were sequenced. Results: After 24 h of sequencing, enough coverage was achieved in order to perform de novo assembly in all three strains. After evaluating different tools, Flye de novo assemblies with medaka polishing were shown to be optimal for in silico Salmonella spp. serotyping with SISRT tool followed by antimicrobial and virulence gene identification with ABRicate. Discussion: The implementation of the present workflow in food safety laboratories with limited computer resources allows a rapid characterization of Salmonella spp. isolates.

2.
Foods ; 12(19)2023 Oct 09.
Artigo em Inglês | MEDLINE | ID: mdl-37835354

RESUMO

The proper functioning of the gastrointestinal tract plays an important role in strengthening the immune system. It is an undeniable fact that lactic acid microorganisms are necessary for the proper functioning of the gastrointestinal tract, the source of which are mainly dairy products. However, there is a problem with the digestibility of lactose; therefore, alternative sources and carriers of probiotics are of particular interest. Due to its dietary and natural properties, protein marshmallow can serve as such a carrier. Therefore, the direction of this study is to identify the dependence of technological factors on the rheological properties of the product and the growth of lactic acid microorganisms in confectionery products enriched with lyophilised strains. According to the results of the study, the following was determined: the optimal technology to produce enriched Belevskaya pastille with a mixture of Lactobacillus acidophilus makes it possible to obtain a product with the necessary rheological properties, utilising a mass drying mode in a dehydrator at 50 °C for 16 h. The strains L. acidophilus M3 and L. acidophilus M4 were the most resistant to a high concentration of bile (40%) in the substrate. Based on the analysis of variance and the obtained regression equations, it was revealed that the growth of lactic acid microorganisms in the product was strongly influenced by the amount of ferment introduced (R² = 0.96). The level of penetration is influenced by factors such as the amount of probiotic starter introduced, the drying time and the interaction of drying time factors on the amount of starter added. The higher the level of penetration, the crumblier the product. The resulting functional product can be characterized as symbiotic since the main raw material of plant origin contains a large amount of fibre, which acts as a prebiotic, and the strain of microorganism, which acts as a probiotic. The data described in the article can be applied in the technological processes of similar products to regulate the structure of the product and vary the dosage of enrichment with probiotic starter cultures.

3.
Nutrients ; 15(15)2023 Aug 01.
Artigo em Inglês | MEDLINE | ID: mdl-37571355

RESUMO

Different research studies have identified specific groups or certain dietary compounds as the onset and progression of obesity and suggested that gut microbiota is a mediator between these compounds and the inflammation associated with pathology. In this study, the objective was to evaluate the dietary intake of 108 overweight (OW), obese (OB), and normal-weight (NW) individuals and to analyze their gut microbiota profile to determine changes and associations with Body Mass Index (BMI) and diet. When individuals were compared by BMI, significant differences in fiber and monounsaturated fatty acids (MUFAs) intake were observed, showing higher adequacy for the NW group. The analysis of gut microbiota showed statistical differences for 18 ASVs; Anaerostipes and Faecalibacterium decreased in the OW/OB group, whereas the genus Oscillospira increased; the genus was also found in the LEFSe analysis as a biomarker for OW/OB. Roseburia faecis was found in a significantly higher proportion of NW individuals and identified as a biomarker for the NW group. Correlation analysis showed that adequation to nutritional recommendation for fiber indicated a higher abundance of Prevotella copri, linearly correlated with F. prausnitzii, Bacteroides caccae, and R. faecis. The same correlation was found for the adequation for MUFAs, with these bacteria being more abundant when the intake was adjusted to or below the recommendations.


Assuntos
Microbioma Gastrointestinal , Sobrepeso , Humanos , Sobrepeso/microbiologia , Obesidade/microbiologia , Dieta , Índice de Massa Corporal , Biomarcadores
4.
Nutrients ; 15(13)2023 Jul 07.
Artigo em Inglês | MEDLINE | ID: mdl-37447396

RESUMO

The work environment is a factor that can significantly influence the composition and functionality of the gut microbiota of workers, in many cases leading to gut dysbiosis that will result in serious health problems. The aim of this paper was to provide a compilation of the different studies that have examined the influence of jobs with unconventional work schedules and environments on the gut microbiota of workers performing such work. As a possible solution, probiotic supplements, via modulation of the gut microbiota, can moderate the effects of sleep disturbance on the immune system, as well as restore the dysbiosis produced. Rotating shift work has been found to be associated with an increase in the risk of various metabolic diseases, such as obesity, metabolic syndrome, and type 2 diabetes. Sleep disturbance or lack of sleep due to night work is also associated with metabolic diseases. In addition, sleep disturbance induces a stress response, both physiologically and psychologically, and disrupts the healthy functioning of the gut microbiota, thus triggering an inflammatory state. Other workers, including military, healthcare, or metallurgy workers, as well as livestock farmers or long-travel seamen, work in environments and schedules that can significantly affect their gut microbiota.


Assuntos
Diabetes Mellitus Tipo 2 , Microbioma Gastrointestinal , Doenças Metabólicas , Probióticos , Jornada de Trabalho em Turnos , Humanos , Disbiose
5.
Front Nutr ; 10: 1170392, 2023.
Artigo em Inglês | MEDLINE | ID: mdl-37125043

RESUMO

Two brown seaweeds (Saccharina japonica and Undaria pinnatifida) were characterized in terms of their nutritional and mineral composition, as well as their potential to modify the human gut microbiota. Nutritional analysis of these seaweeds showed that they comply with the criteria set out in European legislation to be labeled "low fat," "low sugar," and "high fiber." Mineral content analysis showed that 100 g of seaweed provided more than 100% of the daily Ca requirements, as well as 33-42% of Fe, 10-17% of Cu, and 14-17% of Zn requirements. An in vitro human digest simulator system was used to analyze the effect of each seaweed on the human colonic microbiota. The gut microbiota was characterized by 16S rRNA amplicon sequencing and short-chain fatty-acid analysis. Seaweed digestion and fermentation showed beneficial effects, such as a decrease in the phylum Firmicutes and an increase in the phyla Bacteroidetes and Actinobacteria. At the species level, seaweed fermentation increased the proportion of beneficial bacteria such as Parabacteroides distasonis and Bifidobacterium. Regarding of metabolic pathways, no significant differences were found between the two seaweeds, but there were significant differences concerning to the baseline. An increase in short-chain fatty-acid content was observed for both seaweeds with respect to the negative control, especially for acetic acid. Given of the obtained results, S. japonica and U. pinnatifida intake are promising and could open new opportunities for research and application in the fields of nutrition and human health.

6.
J Sci Food Agric ; 103(7): 3638-3644, 2023 May.
Artigo em Inglês | MEDLINE | ID: mdl-36620960

RESUMO

BACKGROUND: Veterinary antibiotics are emerging contaminants and enter into soil principally by agricultural application of organic fertilizers. This article presents the results of the research obtained for the analyzed 70 samples of fertilizers (pig and poultry manure and slurry and digestate) for various classes of antibiotics. RESULTS: Doxycycline, oxytetracycline, tetracycline, lincomycin, tiamulin and enrofloxacin were found in tested samples. Doxycycline was found as a dominant compound, and its highest concentration was 175 mg/kg in pig manure. This investigation indicated that fertilization with manure, especially animal feces, might be the primary source of antibiotics. Additionally, a risk assessment based on a risk quotient was carried out, which showed that the determined concentrations of antibiotics in fertilizers may pose a threat to soil microorganisms. CONCLUSIONS: Results suggested that the ecological risk effects of antibiotic contamination on soil bases and their potential adverse risk on human health needs special attention. © 2023 Society of Chemical Industry.


Assuntos
Antibacterianos , Poluentes do Solo , Humanos , Animais , Suínos , Antibacterianos/análise , Doxiciclina , Fertilizantes/análise , Esterco/análise , Prevalência , Monitoramento Ambiental/métodos , Poluentes do Solo/análise , Solo/química , Aves Domésticas
7.
Foods ; 13(1)2023 Dec 21.
Artigo em Inglês | MEDLINE | ID: mdl-38201064

RESUMO

The objective of this work was to carry out a preliminary study of the fractionation by supercritical CO2 (sc-CO2) extraction of two varieties of Peruvian beans (Phaseolus vulgaris L.), white (WB) and red (RB), to obtain two novel products: an oil rich in essential fatty acids and tocopherols and a defatted flour with high nutritional value and amino acids. The extraction temperature and pressure were optimized using the response surface methodology (RSM) and the extraction kinetics were optimized using the Spline equation. The results revealed that the best extraction conditions for WB and RB were 396.36 Bar, 40.46 °C, with an efficiency of 1.65%; and 391.995 Bar, 44.00 °C, with an efficiency of 1.12%, respectively. The WB and RB oils presented a high degree of polyunsaturation (63.2 and 52.8%, respectively), with oleic, linoleic, and linolenic fatty acids prevailing. Gamma-tocopherol was the predominant antioxidant in both oils. The residual flours (WB and RB) obtained after extraction with sc-CO2 had a high average content of proteins (23%), carbohydrates (61%), and minerals (3%). The limiting amino acids of WB were: Fen + Tyr, Leu, Lys, and in RB, only Leu was limiting. The viscosity of the solutions (20%) of the WB and RB flours mainly adjusted to the Waele's Ostwald model (r = 0.988). It is concluded that both products (oil and bean flour) obtained in an optimized manner using an eco-friendly technology with sc-CO2 have high nutrient and bioactive component content and can be used in the development of new ingredients and healthy foods of plant origin.

8.
Foods ; 11(21)2022 Nov 02.
Artigo em Inglês | MEDLINE | ID: mdl-36360090

RESUMO

Somatotropin is a species-specific polypeptide hormone produced in the pituitary gland of vertebrates. When administered exogenously to cattle, it can increase milk yield. However, the trade and administration of recombinant bovine somatotropin (rbST) to farm animals have been banned in the European Union (EU). Aside from food safety issues, very little is known about the effects of this hormone on milk composition and quality. In this work, a wide profile of fatty acids (the so-called fatty acidome) was determined by GC-FID in raw milk collected from control and rbST-treated lactating cows in a multidose longitudinal study. Milk composition (lactose, protein, fat, dry matter), including minerals (Ca, K, Mg, Na, P), was also determined, and milk yield was recorded. A tendency toward a less saturated profile was observed in the milk collected from animals treated with rbST, with higher concentrations of monounsaturated fatty acids. In addition, less calcium and potassium and more lactose and protein content were observed in milk from treated animals than in regular milk. As a result of this multicomponent profiling of milk, a clear impact of somatotropin treatment on milk quality was observed. The obtained results should be particularly interesting for those countries that permit the use of this hormone in dairy production.

9.
Front Nutr ; 9: 943133, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-36313116

RESUMO

In this study, an undervalued marine crustacean (Talitrus saltator) was characterized in terms of nutritional and heavy metal composition and its potential to affect human gut microbiota. Nutritional analysis of this crustacean revealed that it complies with the criteria established in European legislation to include nutritional claims in their labeling, such as "source of fiber," "low in fat," "low in sugars" and "high in protein." The analysis of the heavy metal content did not reveal any risk derived from the presence of Cd, Hg, or Pb, whereas essential metals contained in 100 g exceeded the minimum daily requirements recommended in Europe for Zn (19.78 mg/kg), Cu (2.28 mg/kg), and Fe (32.96 mg/kg). Using an in vitro system, the effect of T. saltator on the human colonic microbiota shows some beneficial effects, such as fermentation-maintained populations of Bifidobacterium or Lactobacillus, did not increase Firmicutes phylum counts, decreased the Firmicutes/Bacteroidetes ratio, and stimulated 11 metabolic pathways with respect to baseline. These results are unusual in a high protein content-food. However, negative effects were also found in gut microbiota relative proportions, such as an increase in the Proteobacteria phylum and especially some opportunistic bacteria from this phylum, probably due to the antimicrobial effect of chitin on other groups more sensitive to its effect. This work shows for the first time the effect of T. saltator on human colonic microbiota using and in vitro system. The presence of chitin in its composition could provide some beneficial effects by modulating the microbiota, but as T. saltator is a high-protein food, more studies should be carried out showing these benefits.

10.
Nutr Health ; : 2601060221127115, 2022 Oct 12.
Artigo em Inglês | MEDLINE | ID: mdl-36221976

RESUMO

OBJECTIVE: Our aim was to identify changes in population habits induced by COVID-19 confinement in Argentina. METHODS: An internet-based cross-sectional survey was conducted among adults in Argentina on December 2020, requesting possible changes occurring during the COVID-19 outbreak. It included 26 questions regarding general information (age, gender, location), eating habits, desire/anxiety for food or to eat between meals, weight gain, physical activity, and hours of sleep. We ran a descriptive statistical analysis of changes in habits and lifestyle during the confinement, followed by a logistic regression analysis to explore the relation between these changes and weight gain. Results: Out of 1536 survey participants, 57.1% were female, aged 38.8 ± 13.1 years. Data showed that during the outbreak, people experienced significant changes in food intake, physical activity, nutritional supplement consumption, anxiety, and sleeping disorders. These changes in behavior resulted in an elevated percentage of people (39.7%) that gained weight (average 4.8 ± 2.8 kg). Weight gain was associated with more food consumption (OR: 9.398), increased snacking between meals (OR: 1.536), anxiety about food (OR: 3.180), less practice of physical activity (OR: 0.586) and less consumption of nutritional supplements (OR: 0.762). Conclusions: COVID-19 outbreak was associated with unhealthy lifestyle changes and body weight increase. These adverse side effects could be prevented by active promotion of nutritional advice and physical activity, implementing virtual activities associated with regular mass promotion campaigns.

11.
Foods ; 11(16)2022 Aug 09.
Artigo em Inglês | MEDLINE | ID: mdl-36010390

RESUMO

Although milk consumption is increasing worldwide, in some geographical regions, its consumption has persistently declined in recent decades. This fact, together with the increase in milk production prices, has caused both milk producers and the dairy industry to be immersed in a major crisis. Some possible solutions to this problem are to get people who do not currently consume milk to start drinking it again, or to market milk and dairy products with a higher added value. In this context, a type of milk called A2 has recently received attention from the industry. This type of milk, characterized by a difference in an amino acid at position 67 of the ß-casein polypeptide chain, releases much smaller amounts of bioactive opioid peptide ß-casomorphin 7 upon digestion, which has been linked to harmful effects on human health. Additionally, A2 milk has been attributed worse technological properties in the production of some dairy products. Thus, doubts exist about the convenience for the dairy industry to bet on this product. The aim of this review is to provide an update on the effects on human health of A2 milk, as well as its different technological properties to produce dairy products.

12.
Foods ; 11(12)2022 Jun 17.
Artigo em Inglês | MEDLINE | ID: mdl-35741982

RESUMO

The functionality of breast milk in terms of immunity is well-known. Despite this, a significant proportion of breastfed infants exhibit sensitization to different potentially allergenic proteins and clinical reactivity (including anaphylaxis) early in life and before the introduction of complementary feeding for the first time. The potential induction of early oral tolerance to overcome early allergic sensitization through exposure to allergens in breast milk also remains controversial and not yet well-established. The objective of this scoping review is to provide a critical appraisal of knowledge about the content of cow's milk antigens in human milk. The amount of dietary derived milk antigens found in human milk and the analytical methodologies used to detect and quantify these antigens, the allergic status of the mother, the stage of lactation, the time of sampling (before or after ingestion of food), and the impact of human milk allergen on the infant were the outcomes that were assessed. Allergy risk was explored in all reviewed studies and could help to better elucidate its role in the context of allergic disease development. According to the included literature, we can conclude that there are mainly fragments derived from bovine proteins in human milk, and the presence of potentially allergenic molecules is greater in the milk of mothers with an allergic tendency. A clear relationship between maternal diet and allergen content in breast milk could not be firmly concluded though. Also, infants receiving milk from human milk banks, where donor milk is pasteurized for preservation, may be subject to greater risk of allergy development, especially for ß-lactoglobulin.

13.
Food Res Int ; 156: 111156, 2022 06.
Artigo em Inglês | MEDLINE | ID: mdl-35651022

RESUMO

Until now, although different studies have shown the potential prebiotic effect of seaweed carbohydrates, no studies with the whole seaweeds have been carried out. In addition, the prebiotic effect throughput sequencing remains poorly investigated since most of the published works used qPCR or FISH to estimate bacterial changes. In this work, an in vitro model of the human distal colon was used to determine, for the first time, the potential prebiotic effect of a brown whole seaweed Himanthalia elongata. The whole seaweed was characterized in basis of its nutritional and mineral composition and submitted to the entire gastrointestinal digestion. The prebiotic effect was evaluated by the microbial modulation through 16S rRNA amplicon sequencing, qPCR and short-chain fatty acid analysis. The obtained results indicated that the colonic fraction of H. elongata was used selectively by the Bacteroides genus, more specifically by the specie Bacteoides ovatus, whereas inulin was used mainly by the Parabacteroides genus, being Parabacteroides distasonis the most abundant identified specie. Selective use of inulin by P. distasonis is, therefore, reported by the first time. qPCR analysis shown no significative differences in Bifidobacterium population and a decrease in Lactobacillus along the fermentation assays with both substrates. Regarding to the short-fatty acid production, maximal concentration, 56.11 ± 20.48 mM, was achieved for H. elongata, at 24 h of fermentation whereas for inulin total acid production was 93.66 ± 21.82 mM at 48 h of assay. The metabolic pathways associated with bacterial genera were not significantly different between the two tested substrates. Although more studies are necessary to elucidate the prebiotic character of H. elongata, the results presented in this work are promissory and could open new opportunities of research and application in the area of Nutrition and Food Chemistry.


Assuntos
Besouros , Alga Marinha , Animais , Colo/microbiologia , Humanos , Inulina , Prebióticos , RNA Ribossômico 16S/genética , Verduras
14.
Molecules ; 27(5)2022 Feb 22.
Artigo em Inglês | MEDLINE | ID: mdl-35268574

RESUMO

The use of veterinary drugs in animal production is a common practice to secure animal and human health. However, residues of administrated drugs could be present in animal food products. Levels of drugs in food of animal origin are regulated within the European Union. In recent years, residues have been detected not only in food, but also in the environmental elements such as water or soil, meaning that humans are involuntarily exposed to these substances. This article presents a multiclass method for the analysis of various therapeutic groups of pharmaceuticals in human feces. Pharmaceuticals are extracted from feces with an acid extraction solvent, and after filtration the extract was analyzed by HPLC-MS/MS. A limit of detection of 10 ng/g was achieved for 9 pharmaceuticals, with linearity over 0.99 and repeatability and reproducibility lower than 20%. The method was satisfactorily applied in 25 feces samples of individuals that had declared not to be under medical treatment for the last two months. Results indicate the presence of six different compounds at concentration between 10 and 456 ng/g. This preliminary study showed the involuntary exposure of human gut microbiota to active substances such as pharmaceuticals.


Assuntos
Cromatografia Líquida
15.
Molecules ; 28(1)2022 Dec 26.
Artigo em Inglês | MEDLINE | ID: mdl-36615410

RESUMO

Veterinary drugs are frequently employed to treat and prevent diseases in food-producing animals to improve animal health and to avoid the introduction of microorganisms into the food chain. The analysis of the presence of pharmaceutical residues in animal manure could help to evaluate the legal and illegal practices during food production without harming the animals and to correctly manage manure when it is going to be applied as a fertilizer. This article describes a method for the simultaneous analysis of 29 active substances, mostly antibiotics and antiparasitic agents. Substances were extracted from lyophilized manure with a methanol:McIlvaine solution and analyzed with HPLC-ESI-MS/MS and a C18 HPLC column. The method was validated following European guidelines, the achieved trueness was between 63 and 128% (depending on the analytes), and the linearity was between 100 and 1500 µg/kg. The applicability of the method was demonstrated in 40 manure samples collected from pig farms where tetracycline was quantified in 7.5% of the samples. These results show the viability of this non-invasive method for the control of the legal and illegal administration of pharmaceuticals in food-producing animals.


Assuntos
Esterco , Espectrometria de Massas em Tandem , Suínos , Animais , Cromatografia Líquida de Alta Pressão , Espectrometria de Massas em Tandem/métodos , Esterco/análise , Antibacterianos/análise , Tetraciclina
16.
Microbiol Resour Announc ; 10(41): e0076821, 2021 Oct 14.
Artigo em Inglês | MEDLINE | ID: mdl-34647803

RESUMO

Non-enterica subspecies of Salmonella enterica are associated with cold-blood animals. We report the complete genomes of six S. enterica strains (one S. enterica subsp. arizonae strain, four S. enterica subsp. salamae strains, and one S. enterica subsp. diarizonae strain) isolated from Spanish poultry houses. This will increase our knowledge of these non-enterica subspecies.

17.
Artigo em Inglês | MEDLINE | ID: mdl-34477499

RESUMO

Pharmaceuticals and heavy metals are contaminants present in groundwaters, which are the main source of drinking water in most parts of the world. In the northwest region of Spain, Galicia, groundwater harvesting is a common practice for drinking water supply, crop irrigation, cattle watering, as well as recreational use such as filling pools. In order to assess the quality of Galician groundwaters, the presence of 21 pharmaceuticals and 10 heavy metals was analysed by UPLC-MS/MS and ICP/MS methods, respectively, in a total of 118 groundwater samples from private wells. Seventeen of the 21 compounds studied were detected in 28% of the samples, with the highest presence of pharmaceuticals belonging to the antimicrobial group (52%), specifically the sulphonamides group in a range of concentration between 21 and 14.9 ng/L. In addition, 30% of the samples contained at least one heavy metal (Mn, As and Fe) above the legally permitted levels. Evaluation of the risk associated with the consumption of the analysed groundwater indicated no human risk for any of the detected pharmaceuticals but high cancer risk for children due to Cd, Cr and As concentrations was observe.


Assuntos
Antibacterianos/análise , Antifúngicos/análise , Coccidiostáticos/análise , Água Subterrânea/química , Metais Pesados/análise , Poluentes Químicos da Água/análise , Irrigação Agrícola , Animais , Monitoramento Ambiental , Humanos , Espanha
18.
Nutrients ; 13(7)2021 Jul 14.
Artigo em Inglês | MEDLINE | ID: mdl-34371924

RESUMO

The objective of this work was to characterize the microbiota of breast milk in healthy Spanish mothers and to investigate the effects of lactation time on its diversity. A total of ninety-nine human milk samples were collected from healthy Spanish women and were assessed by means of next-generation sequencing of 16S rRNA amplicons and by qPCR. Firmicutes was the most abundant phylum, followed by Bacteroidetes, Actinobacteria, and Proteobacteria. Accordingly, Streptococcus was the most abundant genus. Lactation time showed a strong influence in milk microbiota, positively correlating with Actinobacteria and Bacteroidetes, while Firmicutes was relatively constant over lactation. 16S rRNA amplicon sequencing showed that the highest alpha-diversity was found in samples of prolonged lactation, along with wider differences between individuals. As for milk nutrients, calcium, magnesium, and selenium levels were potentially associated with Streptococcus and Staphylococcus abundance. Additionally, Proteobacteria was positively correlated with docosahexaenoic acid (DHA) levels in breast milk, and Staphylococcus with conjugated linoleic acid. Conversely, Streptococcus and trans-palmitoleic acid showed a negative association. Other factors such as maternal body mass index or diet also showed an influence on the structure of these microbial communities. Overall, human milk in Spanish mothers appeared to be a complex niche shaped by host factors and by its own nutrients, increasing in diversity over time.


Assuntos
Bactérias/crescimento & desenvolvimento , Lactação , Leite Humano/microbiologia , Período Pós-Parto , Adulto , Bactérias/genética , Feminino , Sequenciamento de Nucleotídeos em Larga Escala , Humanos , Microbiota , Pessoa de Meia-Idade , Gravidez , Ribotipagem , Espanha , Fatores de Tempo
19.
Methods Mol Biol ; 2359: 163-170, 2021.
Artigo em Inglês | MEDLINE | ID: mdl-34410668

RESUMO

This contribution describes a fast and facile method for fabrication of robust magnetic stir-bars composed of molecularly imprinted polymers (MIPs) combined with magnetite particles. This was achieved through a prior optimization of the protocol presented here, in particular, the selection of cross-linker and porogen suited for obtaining a durable monolithic magnetic stir-bar. In-house prepared magnetite nanoparticles (Fe3O4) are used as magnetic core, coating them with molecularly imprinted polymers through a simple process of bulk polymerization. Procedures for magnetite synthesis, preparation of polymerization mixture, stir-bar synthesis, and analytical application are described.


Assuntos
Impressão Molecular , Adsorção , Cromatografia Líquida de Alta Pressão , Óxido Ferroso-Férrico , Fenômenos Magnéticos , Polímeros Molecularmente Impressos
20.
AIMS Microbiol ; 7(2): 238-256, 2021.
Artigo em Inglês | MEDLINE | ID: mdl-34250377

RESUMO

Salmonella spp. is one of the main foodborne pathogens around the world. It has a cyclic lifestyle that combines host colonization with survival outside the host, implying that Salmonella has to adapt to different conditions rapidly in order to survive. One of these environments outside the host is the food production chain. In this environment, this foodborne pathogen has to adapt to different stress conditions such as acidic environments, nutrient limitation, desiccation, or biocides. One of the mechanisms used by Salmonella to survive under such conditions is biofilm formation. Quorum sensing plays an important role in the production of biofilms composed of cells from the same microorganism or from different species. It is also important in terms of food spoilage and regulates the pathogenicity and invasiveness of Salmonella by regulating Salmonella pathogenicity islands and flagella. Therefore, in this review, we will discuss the genetic mechanism involved in Salmonella quorum sensing, paying special attention to small RNAs and their post-regulatory activity in quorum sensing. We will further discuss the importance of this cell-to-cell communication mechanism in the persistence and spoilage of Salmonella in the food chain environment and the importance in the communication with microorganisms from different species. Subsequently, we will focus on the role of quorum sensing to regulate the virulence and invasion of host cells by Salmonella and on the interaction between Salmonella and other microbial species. This review offers an overview of the importance of quorum sensing in the Salmonella lifestyle.

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