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1.
Food Microbiol ; 115: 104341, 2023 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-37567642

RESUMO

Salmonella Enteritidis is the main serotype responsible for human salmonellosis in the European Union. One of the main sources of Salmonella spp. in the food chain are poultry products, such as eggs or chicken meat. In recent years, molecular methods have become an alternative to culture dependent methods for the rapid screening of Salmonella spp. In this work, the strain S. Enteritidis S1400, and previously isolated and characterized bacteriophage PVP-SE2, were used to develop and evaluate a same-day detection method combining Phage Amplification and Loop-mediated isothermal amplification (PA-LAMP) to specifically detect viable S. Enteritidis in chicken breast. This method is based on the detection of the phage DNA rather than bacterial DNA. The virus is added to the sample during pre-enrichment in buffered peptone water, where it replicates in the presence of viable S. Enteritidis. The detection of phage DNA allows, on the one hand to detect viable bacteria, since viruses only replicate in them, and on the other hand to increase the sensitivity of the method since for each infected S. Enteritidis cell, hundreds of new viruses are produced. Two different PA-LAMP detection strategies were evaluated, a real time fluorescence and a naked-eye detection. The present method could down to 0.2 fg/µL of pure phage DNA and a concentration of viral particles of 2.2 log PFU/mL. After a short Salmonella recovery step of 3 h and a co-culture of 4 h of the samples with phage particles, both real-time fluorescence and naked-eye method showed a LoD95 of 6.6 CFU/25 g and a LoD50 of 1.5/25 g in spiked chicken breast samples. The entire detection process, including DNA extraction and LAMP analysis, can be completed in around 8 h. In the current proof-of-concept, the novel PA-LAMP obtained comparable results to those of the reference method ISO 6579, to detect Salmonella Enteritidis in poultry meat.


Assuntos
Bacteriófagos , Salmonella enteritidis , Animais , Humanos , Salmonella enteritidis/genética , Aves Domésticas , Microbiologia de Alimentos , Carne/microbiologia
2.
Molecules ; 25(4)2020 Feb 24.
Artigo em Inglês | MEDLINE | ID: mdl-32102343

RESUMO

Human gut microbiota plays an important role in several metabolic processes and human diseases. Various dietary factors, including complex carbohydrates, such as polysaccharides, provide abundant nutrients and substrates for microbial metabolism in the gut, affecting the members and their functionality. Nowadays, the main sources of complex carbohydrates destined for human consumption are terrestrial plants. However, fresh water is an increasingly scarce commodity and world agricultural productivity is in a persistent decline, thus demanding the exploration of other sources of complex carbohydrates. As an interesting option, marine seaweeds show rapid growth and do not require arable land, fresh water or fertilizers. The present review offers an objective perspective of the current knowledge surrounding the impacts of seaweeds and their derived polysaccharides on the human microbiome and the profound need for more in-depth investigations into this topic. Animal experiments and in vitro colonic-simulating trials investigating the effects of seaweed ingestion on human gut microbiota are discussed.


Assuntos
Fibras na Dieta/farmacologia , Microbioma Gastrointestinal/efeitos dos fármacos , Microbiota/efeitos dos fármacos , Polissacarídeos/farmacologia , Prebióticos/análise , Alga Marinha/química , Animais , Clorofíceas/química , Fibras na Dieta/metabolismo , Fermentação , Microbioma Gastrointestinal/fisiologia , Humanos , Camundongos , Microbiota/fisiologia , Phaeophyceae/química , Polissacarídeos/química , Polissacarídeos/isolamento & purificação , Prebióticos/provisão & distribuição , Ratos , Rodófitas/química
3.
Microb Pathog ; 137: 103771, 2019 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-31580958

RESUMO

Salmonella is a major global food-borne pathogen. One of the main concerns related to Salmonella and other food-borne pathogens is their capacity to acquire antimicrobial resistance and produce biofilms. Due to the increased resistance to common antimicrobials used to treat livestock animals and human infections, the discovery of new antimicrobial substances is one of the main challenges in microbiological research. An additional challenge is the development of new methods and substances to inhibit and destruct biofilms. We determined the antimicrobial and antibiofilm activities of apitoxin in 16 Salmonella strains isolated from poultry. In addition, the effect of apitoxin on Salmonella motility and the expression of biofilm- and virulence-related genes was evaluated. The minimum inhibitory concentrations (MIC) of apitoxin ranged from 1,024-256 µg/mL, with 512 µg/mL being the most common. Sub-inhibitory concentrations of apitoxin significantly reduced biofilm formation in 14 of the 16 Salmonella strains tested, with significant increases in motility. MIC concentrations of apitoxin destroyed the pre-formed biofilm by 27.66-68.22% (47.00% ±â€¯10.91). The expression of biofilm- and virulence-related genes and small RNAs was differentially regulated according to the strain and the presence of apitoxin. The transcription of the small RNAs dsrA and csrB, related to antimicrobial resistance, was upregulated in the presence of apitoxin. We suggest that apitoxin is a potential antimicrobial substance that could be used in combination with other substances to develop new drugs and sanitizers against food-borne pathogens.


Assuntos
Antibacterianos/farmacologia , Venenos de Abelha/farmacologia , Abelhas/química , Doenças das Aves Domésticas/microbiologia , Salmonelose Animal/microbiologia , Salmonella enterica/efeitos dos fármacos , Animais , Antibacterianos/isolamento & purificação , Proteínas de Bactérias/genética , Proteínas de Bactérias/metabolismo , Venenos de Abelha/isolamento & purificação , Biofilmes/efeitos dos fármacos , Regulação Bacteriana da Expressão Gênica/efeitos dos fármacos , Testes de Sensibilidade Microbiana , Aves Domésticas , Salmonella enterica/genética , Salmonella enterica/isolamento & purificação , Salmonella enterica/fisiologia
4.
Molecules ; 23(7)2018 Jul 13.
Artigo em Inglês | MEDLINE | ID: mdl-30011805

RESUMO

The use of recombinant bovine somatotropin (rbST) in dairy cattle is forbidden in the European Union. Due to the very low circulating concentration of rbST in treated animals, its direct detection is still a challenge. Therefore, the use of indirect methods to detect the ab(use) of rbST in dairy cattle appears as a good alternative. In the past few years, gene expression demonstrated its utility in screening the use of illicit substances in both humans and animals. In this study, a comparison of three types of matrices (milk somatic cells, blood, and hair follicles) was carried out to evaluate their potential use for routine control of rbST using 15 gene-expression profiles. A total of six rbST-treated cows and three control cows were included in the study. A subcutaneous injection containing 500 mg of rbST was administered to the treated group. Samples of the three matrices were collected before rbST administration, and at three and nine days after treatment. The quality of RNA extracted was higher in the blood and hair-follicle samples than in the milk somatic cells. In the three matrices, there were significant differences in the expression of some genes, with milk somatic cells and blood presenting the the best matrices. On this note, the cyclin D1 (CCND1), interleukin 1 beta (IL-1ß), tumor necrosis factor (TNF), and insulin-like growth factor 1 receptor (IGF-1R) genes showed potential as biomarkers of rbST treatment. Therefore, blood, somatic cells, and follicle hair should be considered as promising sources of RNA, and can be used in gene-expression assays to routinely control the illicit use of rbST.


Assuntos
Anticorpos/química , Regulação da Expressão Gênica/efeitos dos fármacos , Hormônio do Crescimento , Folículo Piloso/metabolismo , Leite/metabolismo , Animais , Bovinos , Feminino , Hormônio do Crescimento/sangue , Hormônio do Crescimento/química , Hormônio do Crescimento/farmacologia , Proteínas Recombinantes/química , Proteínas Recombinantes/farmacologia
5.
J Sci Food Agric ; 98(11): 4014-4032, 2018 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-29424050

RESUMO

It takes several steps to bring food from the farm to the fork (dining table), and contamination with food-borne pathogens can occur at any point in the process. Campylobacter spp. and Salmonella spp. are the main microorganisms responsible for foodborne disease in the EU. These two pathogens are able to persist throughout the food supply chain thanks to their ability to form biofilms. Owing to the high prevalence of Salmonella and especially of Campylobacter in the food supply chain and the huge efforts of food authorities to reduce these levels, it is of great importance to fully understand their mechanisms of persistence. Diverse studies have evaluated the biofilm-forming capacity of foodborne pathogens isolated at different steps of food production. Nonetheless, the principal obstacle of these studies is to reproduce the real conditions that microorganisms encounter in the food supply chain. While there are a wide number of Salmonella biofilm studies, information on Campylobacter biofilms is still limited. A comparison between the two microorganisms could help to develop new research in the field of Campylobacter biofilms. Therefore, this review evaluates relevant work in the field of Salmonella and Campylobacter biofilms and the applicability of the data obtained from these studies to real working conditions. © 2018 Society of Chemical Industry.


Assuntos
Biofilmes , Campylobacter/fisiologia , Doenças Transmitidas por Alimentos/microbiologia , Salmonella/fisiologia , Animais , Campylobacter/classificação , Campylobacter/genética , Campylobacter/isolamento & purificação , Contaminação de Alimentos/análise , Humanos , Salmonella/classificação , Salmonella/genética , Salmonella/isolamento & purificação
6.
Foods ; 13(11)2024 May 24.
Artigo em Inglês | MEDLINE | ID: mdl-38890864

RESUMO

Loop-mediated isothermal amplification, LAMP, is nowadays the most popular isothermal nucleic acid amplification technique, and as such, several commercial, ready-to-use master mixes have flourished. Unfortunately, independent studies to determine their performance are limited. The current study performed an independent evaluation of the existing ready-to-use commercial LAMP master mixes WarmStart® LAMP Kit, LavaLAMP™ DNA Master Mix, Saphir Bst Turbo GreenMaster, OptiGene Fast Master Mix ISO-004, and SynLAMP Mix. To reduce bias, three different genes, namely ttr (Salmonella spp.), rfbE (E. coli O157), and hly (Listeria monocytogenes), were targeted. The comparison was based on amplification speed, performance with decreasing DNA concentrations, and the effect of five typical LAMP reaction additives (betaine, DMSO, pullulan, TMAC, and GuHCl). Significant differences were observed among the different master mixes. OptiGene provided the fastest amplification and showed less detrimental effects associated with the supplements evaluated. Out of the chemicals tested, pullulan provided the best results in terms of amplification speed. It is noteworthy that the different additives impacted the master mixes differently. Overall, the current study provides insights into the performance of commercial LAMP master mixes, which can be of value for the scientific community to better select appropriate reagents when developing new methods.

7.
Curr Res Food Sci ; 8: 100716, 2024.
Artigo em Inglês | MEDLINE | ID: mdl-38511154

RESUMO

Rapid identification of Shiga toxin-producing Escherichia coli, or STEC, is of utmost importance to assure the innocuousness of the foodstuffs. STEC have been implicated in outbreaks associated with different types of foods however, among them, ready-to-eat (RTE) vegetables are particularly problematic as they are consumed raw, and are rich in compounds that inhibit DNA-based detection methods such as qPCR. In the present study a novel method based on Loop-mediated isothermal amplification (LAMP) to overcome the limitations associated with current molecular methods for the detection of STEC in RTE vegetables targeting stx1 and stx2 genes. In this sense, LAMP demonstrated to be more robust against inhibitory substances in food. In this study, a comprehensive enrichment protocol was combined with four inexpensive DNA extraction protocols. The one based on silica purification enhanced the performance of the method, therefore it was selected for its implementation in the final method. Additionally, three different detection chemistries were compared, namely real-time fluorescence detection, and two end-point colorimetric strategies, one based on the addition of SYBR Green, and the other based on a commercial colorimetric master mix. After optimization, all three chemistries demonstrated suitable for the detection of STEC in spiked RTE salad samples, as it was possible to reach a LOD50 of 0.9, 1.4, and 7.0 CFU/25 g for the real-time, SYBR and CC LAMP assays respectively. All the performance parameters reached values higher than 90 %, when compared to a reference method based on multiplex qPCR. More specifically, the analytical sensitivity was 100, 90.0 and 100 % for real-time, SYBR and CC LAMP respectively, the specificity 100 % for all three assays, and accuracy 100, 96 and 100 %. Finally, a high degree of concordance was also obtained (1, 0.92 and 1 respectively). Considering the current technological advances, the method reported, using any of the three detection strategies, demonstrated suitable for their implementation in decentralized settings, with low equipment resources.

8.
Nutrients ; 16(11)2024 Jun 05.
Artigo em Inglês | MEDLINE | ID: mdl-38892701

RESUMO

This systematic review aimed to evaluate the effectiveness of the independent or combined use of nutritional ergogenic aids belonging to Group A of the ABCD classification by the Australian Institute of Sport (AIS) in the context of cycling (caffeine, creatine, sodium bicarbonate, beta-alanine, nitrates, and glycerol). A comprehensive search was carried out using three databases: PubMed, Scopus, and Web of Science. All the databases were searched for Randomized Controlled Trials or crossover design studies assessing the effects of supplementation on cycling performance in comparison with placebos in healthy adults. The methodological quality of each study was evaluated using the Physiotherapy Evidence Database scale. Thirty-six articles involving 701 participants were included in this review, examining supplementation with caffeine (n = 5), creatine (n = 2), sodium bicarbonate (n = 6), beta-alanine (n = 3), and nitrates (n = 8). Additionally, supplemental combinations of caffeine and creatine (n = 3), caffeine and sodium bicarbonate (n = 3), caffeine and nitrates (n = 1), creatine and sodium bicarbonate (n = 1), and sodium bicarbonate and beta-alanine (n = 4) were analyzed. A benefit for cyclists' athletic performnce was found when consuming a caffeine supplement, and a potential positive effect was noted after the consumption of sodium bicarbonate, as well as after the combination of caffeine and creatine. However, no statistically significant effects were identified for the remaining supplements, whether administered individually or in combination.


Assuntos
Desempenho Atlético , Ciclismo , Cafeína , Creatina , Suplementos Nutricionais , Nitratos , Substâncias para Melhoria do Desempenho , Humanos , Ciclismo/fisiologia , Desempenho Atlético/fisiologia , Nitratos/administração & dosagem , Substâncias para Melhoria do Desempenho/administração & dosagem , Cafeína/administração & dosagem , Creatina/administração & dosagem , Bicarbonato de Sódio/administração & dosagem , beta-Alanina/administração & dosagem , beta-Alanina/farmacologia , Adulto , Masculino , Feminino , Ensaios Clínicos Controlados Aleatórios como Assunto
9.
Foods ; 13(14)2024 Jul 09.
Artigo em Inglês | MEDLINE | ID: mdl-39063248

RESUMO

Maternal diet plays a significant role in the fatty acid composition of breast milk. Dietary products such as milk and meat are the primary sources of natural TFAs for humans. These peculiar fatty acids hold nutritional significance as they not only lack the detrimental effects of industrially produced trans fats on the endothelium characteristic, but they also exhibit anti-inflammatory properties. The relationship between the presence of eight fatty acids in breast milk (including natural TFAs trans-vaccenic and conjugated linoleic acid) and the maternal diet has been explored, and their abundance has been compared to that of infant formulas. Two cohorts of lactating women, originating from a Spanish region, participated in this study; they adhered to the Southern European Atlantic diet or the Atlantic diet. While the consumption of conventional meat or dairy products does not seem to increase the abundance of TFAs in breast milk, trans-vaccenic and oleic acid are among the most distinctive features of breast milk fat in mothers consuming naturally improved dairy products with an improved fatty acid profile. The most significant differences between natural breastfeeding and formula feeding lie in natural TFAs, since formulas are notably deficient in natural TFAs while being overfortified in alpha-linolenic acid in comparison to breast milk. We suggest an improvement in the formulation of these products through using cow's milk with an optimal fatty acid profile that better mimics the fatty acid composition found in human milk.

10.
Talanta ; 260: 124642, 2023 Aug 01.
Artigo em Inglês | MEDLINE | ID: mdl-37167680

RESUMO

Loop-mediated isothermal amplification, or LAMP, is nowadays the most popular isothermal nucleic acid amplification technique. This technique implements a minimum of four primers, named outer (F3/B3) and inner primers (FIP/BIP). The inner primers hybridize in two distinct regions, and some studies have reported that the usage of a linker, typically composed of four thymines, in the middle of these primers can improve assay performance. In addition to this, dual-priming oligonucleotides, DPO, have been reported to provide highly specific reducing non-specific amplifications. Considering the large number of primers implemented in LAMP assays, in the current study the suitability of DPO primers replacing regular outer primers; and their combination with different linker sequences in the inner primers were explored. The results demonstrated that replacing standard F3/B3 by DPO primers does not significantly affect that overall performance of the assay, and provides additional stability to temperature changes. This observations were consistent regardless the type of linker implemented in the inner primers, out of which in the current study a linker composed of thymines significantly outperformed the other options tested, most likely due to a combination of sequence and physical structure.


Assuntos
Técnicas de Amplificação de Ácido Nucleico , Oligonucleotídeos , Primers do DNA , Técnicas de Amplificação de Ácido Nucleico/métodos , DNA Bacteriano , Sensibilidade e Especificidade
11.
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.

12.
Foods ; 13(1)2023 Dec 23.
Artigo em Inglês | MEDLINE | ID: mdl-38201091

RESUMO

Multiplex assays implementing DNA-based methods have been demonstrated as suitable alternatives to culture-based microbiological methods; however, in most cases, they still require a suitable enrichment step. Finding suitable enrichment conditions for different bacteria may result in challenges. In the present study, a novel selective broth named MSB (mTA10 selective broth) was formulated for the simultaneous recovery of Salmonella spp., E. coli O157:H7 and L. monocytogenes. Attention was paid to ensure the optimal enrichment of L. monocytogenes as its enrichment is more challenging. To this end, cellobiose was added to increase the growth of L. monocytogenes, and sodium pyruvate was also added to improve the recovery of stressed bacteria. Four selective agents were added, namely nalidixic acid, sodium cholate, lithium chloride and potassium tellurite, to control the growth of interfering microorganisms. It was concluded that the novel broth was suitable for the simultaneous enrichment of the target pathogens, allowing them to reach concentrations higher than 7 log CFU/mL for each bacterium in pure culture. Furthermore, all heavily contaminated ready-to-eat salad samples reached concentrations higher than 5 log CFU/g. Finally, after 24 h of enrichment of spiked salad, it was possible to detect concentrations below 10 CFU/25 g.

13.
Methods Mol Biol ; 2967: 63-73, 2023.
Artigo em Inglês | MEDLINE | ID: mdl-37608103

RESUMO

Shiga toxin-producing Escherichia coli (STEC) is a group of human foodborne pathogens transmitted to humans through the consumption of different types of food. Their detection is mainly performed by targeting specific serogroups by classical microbiological methods and, later, by molecular typing with different techniques. The application of multiplex real-time PCR (qPCR) can significantly improve the turnaround time of the existing methodologies as in one single run it is possible to detect and characterize specific microorganisms. In the present chapter, a pentaplex qPCR assay is described for the identification of STEC which may also be applied for the rapid screening of these pathogens in different types of foods. The assay targets the most important virulence factors of these microorganisms, the genes stx1, stx2, and eae, along with the rfbE gene which encodes for the "O157" antigen as this is the most prevalent serogroup among all STEC, as well as an internal amplification control to rule out false-negative results due to qPCR inhibition.


Assuntos
Escherichia coli Shiga Toxigênica , Humanos , Escherichia coli Shiga Toxigênica/genética , Reação em Cadeia da Polimerase em Tempo Real , Alimentos , Bioensaio , Técnicas Microbiológicas
14.
Nutrients ; 15(4)2023 Feb 15.
Artigo em Inglês | MEDLINE | ID: mdl-36839335

RESUMO

The human gastrointestinal tract contains large communities of microorganisms that are in constant interaction with the host, playing an essential role in the regulation of several metabolic processes. Among the gut microbial communities, the gut bacteriome has been most widely studied in recent decades. However, in recent years, there has been increasing interest in studying the influences that other microbial groups can exert on the host. Among them, the gut virome is attracting great interest because viruses can interact with the host immune system and metabolic functions; this is also the case for phages, which interact with the bacterial microbiota. The antecedents of virome-rectification-based therapies among various diseases were also investigated. In the near future, stool metagenomic investigation should include the identification of bacteria and phages, as well as their correlation networks, to better understand gut microbiota activity in metabolic disease progression.


Assuntos
Bacteriófagos , Microbioma Gastrointestinal , Microbiota , Vírus , Humanos , Viroma , Vírus/metabolismo
15.
Anal Chim Acta ; 1267: 341357, 2023 Aug 01.
Artigo em Inglês | MEDLINE | ID: mdl-37257973

RESUMO

BACKGROUND: Ready-to-eat products, such as leafy greens, must be carefully controlled as they are directly consumed without any treatment to reduce the presence of potential pathogens. Food industries, especially those that process products with short shelf-life, demand rapid detection of foodborne pathogens such as Shiga Toxin-producing Escherichia coli (STEC). In this sense, molecular methods can fulfill both requirements of turnaround time and consumer safety. The most popular rapid methods are those based on real-time PCR (qPCR) however, vegetables contain inhibitory compounds that may inhibit the amplification reaction thus, there is a need for novel sample preparation protocols. RESULTS: In the current study, a low-cost sample treatment based on sequential filtration steps was developed. This protocol was combined with covalent organic frameworks (COFs), and compared against a chelating resin, to evaluate their performance by multiplex qPCR targeting the major virulence genes of STEC, namely stx1, stx2, and eae, along with the rfbE for the specific identification of serogroup O157 due to its particularly high incidence, and an Internal Amplification Control to assess reaction inhibition. The optimized sample treatment effectively removed vegetable qPCR inhibitory compounds, and it was possible to detect STEC in spiked ready-to-eat salad samples in one working day, roughly 5 h, with an LOD50 of 8.7 CFU/25 g with high diagnostic sensitivity and specificity. The method was also assessed in samples with cold-stressed bacteria with good results, further demonstrating its applicability. SIGNIFICANCE: It was demonstrated for the first time that COFs are suitable for DNA extraction and purification. In addition to this, due to the tunable nature of these materials, it is envisioned that future modifications in terms of pore size or combination with magnetic materials, will allow to further improve their performance. In addition to this, the rapid and low-cost sample treatment protocol developed demonstrated suitable for the rapid screening of STEC vegetable samples.


Assuntos
Infecções por Escherichia coli , Proteínas de Escherichia coli , Estruturas Metalorgânicas , Saladas , Escherichia coli Shiga Toxigênica , Humanos , Escherichia coli Shiga Toxigênica/genética , Microbiologia de Alimentos , Reação em Cadeia da Polimerase em Tempo Real/métodos , Infecções por Escherichia coli/epidemiologia , Infecções por Escherichia coli/microbiologia , Fezes/microbiologia
16.
Microorganisms ; 10(1)2022 Jan 07.
Artigo em Inglês | MEDLINE | ID: mdl-35056575

RESUMO

Salmonella spp. and antimicrobial resistant microorganisms are two of the most important health issues worldwide. In the present study, strains naturally isolated from mussels harvested in Galicia (one of the main production areas in the world), were genetically characterized attending to the presence of virulence and antimicrobial resistance genes. Additionally, the antimicrobial profile was also determined phenotypically. Strains presenting several virulence genes were isolated but lacked all the antimicrobial resistance genes analyzed. The fact that some of these strains presented multidrug resistance, highlighted the possibility of bearing different genes than those analyzed, or resistance based on completely different mechanisms. The current study highlights the importance of constant surveillance in order to improve the safety of foods.

17.
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.

18.
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.

19.
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.

20.
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.

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