RESUMEN
Plant microbiomes have been extensively studied for their agricultural relevance on growth promotion and pathogenesis, but little is known about their role as part of the diet when fresh fruits and vegetables are consumed raw. Most studies describing these communities are based on 16S rRNA gene amplicon surveys, limiting our understanding of the taxonomic resolution at the species level and functional capabilities. In this study, we characterized microbes colonizing tomatoes, spinach, brined olives, and dried figs using shotgun metagenomics. We recovered metagenome-assembled genomes of novel lactic acid bacteria from green olives and identified high intra- and inter-specific diversity of Pseudomonas in tomatoes. All samples were colonized by Pseudomonas, consistent with other reports with distinct community structure. Functional characterization showed the presence of enzymes involved in vitamin and short chain fatty acid metabolism and degradation of diverse carbohydrate substrates including plant fibers. The dominant bacterial members were isolated, sequenced, and mapped to its metagenome confirming their identity and indicating the microbiota is culturable. Our results reveal high genetic diversity, previously uncultured genera, and specific functions reflecting a likely plant host association. This study highlights the potential that plant microbes can play when consumed as part of our diet and proposes these as transient contributors to the gut microbiome.
Asunto(s)
Biodiversidad , Interacciones Microbiota-Huesped , Metagenoma , Metagenómica , Microbiota , Plantas Comestibles/microbiología , Biología Computacional/métodos , Microbiología de Alimentos , Variación Genética , Humanos , Metagenómica/métodos , Anotación de Secuencia Molecular , FilogeniaRESUMEN
Analysis of consumer preferences and willingness-to-pay (WTP) for sustainable foods produced using new agri-food technologies is required to enhance the uptake of innovations that accelerate the transition towards sustainable food systems. Consumers' willingness to buy new food products, with no or limited consumption experience, mainly depends on their food choice motivational orientations (promotion- vs prevention-orientation). The objective of this study was to elicit consumers' WTP for foods that are produced with microbial applications during the plant production phase with the aim to reduce the use of synthetic chemicals in crop farming, as well as to understand the associations of food choice motives, personal and socio-demographic factors with the WTP. We used contingent valuation to elicit consumers' WTP for three food products (wheat bread, consumer potatoes and tomato sauce) through online surveys. Data were collected from 291 consumers, primarily from Italy, Germany and the Netherlands. Descriptive statistics, latent variable modelling and logistic regression were used to analysis data. Results show that more than two-third of the respondents are willing to pay premiums of at least 0.11 euro per kg of food products for reductions in synthetic chemical use by at least 50% due to microbial applications. The amount of WTP increases with the level of reductions in synthetic chemical use. The majority of the respondents are promotion-oriented consumers in relation to their food involvement, and are more likely to pay premiums for the sustainably produced food products. Environmentally concerned consumers are also more likely to pay premiums, whereas health concerned consumers are not. This study contributes to understanding of consumers' attitude and perceived health risks towards foods obtained using microbial applications, and the heterogeneity of their preferences. Results provide insights for identifying potential buyers of foods produced using microbial applications, and to set prices according to the levels of consumers' WTP.
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Comportamiento del Consumidor/economía , Plantas Comestibles/crecimiento & desarrollo , Preferencias Alimentarias , Alemania , Humanos , Italia , Modelos Logísticos , Países Bajos , Sistemas en Línea , Plantas Comestibles/microbiologíaRESUMEN
Arabinose is a major plant aldopentose in the form of arabinans complexed in cell wall polysaccharides or glycoproteins (AGP), but comparatively rare as a monosaccharide. l-arabinose is an important bacterial metabolite, accessed by pectolytic micro-organisms such as Pectobacterium atrosepticum via pectin and hemicellulose degrading enzymes. However, not all plant-associated microbes encode cell-wall-degrading enzymes, yet can metabolize l-arabinose, raising questions about their use of and access to the glycan in plants. Therefore, we examined l-arabinose metabolism in the food-borne pathogen Escherichia coli O157:H7 (isolate Sakai) during its colonization of plants. l-arabinose metabolism (araBA) and transport (araF) genes were activated at 18 °C in vitro by l-arabinose and expressed over prolonged periods in planta. Although deletion of araBAD did not impact the colonization ability of E. coli O157:H7 (Sakai) on spinach and lettuce plants (both associated with STEC outbreaks), araA was induced on exposure to spinach cell-wall polysaccharides. Furthermore, debranched and arabinan oligosaccharides induced ara metabolism gene expression in vitro, and stimulated modest proliferation, while immobilized pectin did not. Thus, E. coli O157:H7 (Sakai) can utilize pectin/AGP-derived l-arabinose as a metabolite. Furthermore, it differs fundamentally in ara gene organization, transport and regulation from the related pectinolytic species P. atrosepticum, reflective of distinct plant-associated lifestyles.
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Arabinosa/metabolismo , Escherichia coli O157/metabolismo , Plantas Comestibles/microbiología , Proteínas Portadoras/genética , Proteínas Portadoras/metabolismo , Recuento de Colonia Microbiana , Escherichia coli O157/genética , Escherichia coli O157/crecimiento & desarrollo , Proteínas de Escherichia coli/genética , Proteínas de Escherichia coli/metabolismo , Microbiología de Alimentos , Lactuca/microbiología , Fosfotransferasas (Aceptor de Grupo Alcohol)/genética , Fosfotransferasas (Aceptor de Grupo Alcohol)/metabolismo , Spinacia oleracea/microbiologíaRESUMEN
This study aimed at developing a predictive model that captures the influences of a variety of agricultural and environmental variables and is able to predict the concentrations of enteric bacteria in soil amended with untreated Biological Soil Amendments of Animal Origin (BSAAO) under dynamic conditions. We developed and validated a Random Forest model using data from a longitudinal field study conducted in mid-Atlantic United States investigating the survival of Escherichia coli O157:H7 and generic E. coli in soils amended with untreated dairy manure, horse manure, or poultry litter. Amendment type, days of rain since the previous sampling day, and soil moisture content were identified as the most influential agricultural and environmental variables impacting concentrations of viable E. coli O157:H7 and generic E. coli recovered from amended soils. Our model results also indicated that E. coli O157:H7 and generic E. coli declined at similar rates in amended soils under dynamic field conditions.The Random Forest model accurately predicted changes in viable E. coli concentrations over time under different agricultural and environmental conditions. Our model also accurately characterized the variability of E. coli concentration in amended soil over time by providing upper and lower prediction bound estimates. Cross-validation results indicated that our model can be potentially generalized to other geographic regions and incorporated into a risk assessment for evaluating the risks associated with application of untreated BSAAO. Our model can be validated for other regions and predictive performance also can be enhanced when data sets from additional geographic regions become available.
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Escherichia coli O157/aislamiento & purificación , Escherichia coli/aislamiento & purificación , Estiércol/microbiología , Microbiología del Suelo , Agricultura , Animales , Carga Bacteriana , Microbiología de Alimentos , Humanos , Modelos Biológicos , Plantas Comestibles/crecimiento & desarrollo , Plantas Comestibles/microbiología , Medición de Riesgo , Estadísticas no ParamétricasRESUMEN
Edible plant Jiaosu (EPJ), a type of plant-based functional food fermented by beneficial bacteria, has gained publicity in recent years for its potential benefits to health. Important progress in relevant manufacturing technology has been made in the past decade with respect to raw materials, fermentation microorganisms and fermentation conditions. Current research has revealed that EPJ contains abundant nutrients and bioactive compounds, such as minerals, amino acids, polyphenols, organic acids and polysaccharides. Thus, many studies have focused on the beneficial effects of EPJ in preventing lifestyle diseases, such as hyperglycemia, hyperlipidemia, non-alcoholic fatty liver, obesity, diabetes and some cancers, although limited studies have involved the related active compounds and their protective mechanisms. Furthermore, very few studies have investigated the potential safety risks associated with the consumption of such food. In this review, we present a brief summary of the current research progress pertaining to the manufacturing, bioactive compounds, potential health benefits and safety aspects of EPJ. However, as a result of the complex components in EPJ, further studies on the bioactive compounds with relevant beneficial effects in EPJ and the safety evaluations of EPJ consumption are needed. © 2020 Society of Chemical Industry.
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Alimentos Fermentados/análisis , Plantas Comestibles/química , Plantas Comestibles/metabolismo , Bacterias/metabolismo , Alimentos Fermentados/microbiología , Microbiología de Alimentos , Inocuidad de los Alimentos , Salud , Humanos , Valor Nutritivo , Plantas Comestibles/microbiologíaRESUMEN
LactococcusCeduovirus (formerly c2virus) bacteriophages are among the three most prevalent phage types reported in dairy environments. Phages from this group conduct a strictly lytic lifestyle and cause substantial losses during milk fermentation processes, by infecting lactococcal host starter strains. Despite their deleterious activity, there are limited research data concerning Ceduovirus phages. To advance our knowledge on this specific phage group, we sequenced and performed a comparative analysis of 10 new LactococcuslactisCeduovirus phages isolated from distinct dairy environments. Host range studies allowed us to distinguish the differential patterns of infection of L. lactis cells for each phage, and revealed a broad host spectrum for most of them. We showed that 40% of the studied Ceduovirus phages can infect both cremoris and lactis strains. A preference to lyse strains with the C-type cell wall polysaccharide genotype was observed. Phage whole-genome sequencing revealed an average nucleotide identity above 80%, with distinct regions of divergence mapped to several locations. The comparative approach for analyzing genomic data and the phage lytic spectrum suggested that the amino acid sequence of the orf8-encoded putative tape measure protein correlates with host range. Phylogenetic studies revealed separation of the sequenced phages into two subgroups. Finally, we identified three types of phage origin of replication regions, and showed they are able to support plasmid replication without additional phage proteins.
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Bacteriófagos/fisiología , Lactococcus/virología , Plantas Comestibles/microbiología , Bacteriófagos/clasificación , Bacteriófagos/aislamiento & purificación , Bacteriófagos/ultraestructura , Clonación Molecular , Genoma Viral , Genómica , Especificidad del Huésped , Plásmidos/genética , Reacción en Cadena de la Polimerasa , Polimorfismo de Longitud del Fragmento de Restricción , Fenómenos Fisiológicos de los VirusRESUMEN
The role of plant-based foods in the epidemiology of antimicrobial resistance has been inadequately studied. In this investigation, resistant organisms from vegetables, fruits and spices imported into Canada were identified and characterized. A total of 143 products imported from primarily Asian and African countries were purchased from international markets in Saskatoon, Saskatchewan. Samples were selectively cultured for bacterial species where resistance is known to be emerging. The proportions of samples positive for each organism were as follows: E. coli (n = 13, 9.1%), Salmonella spp. (n = 2, 1.4%), ESBL producing Enterobacter spp. (n = 2, 1.4%) and K. pneumoniae (n = 2, 1.4%), S. aureus (n = 7, 4.9%) and Enterococcus spp. (n = 66, 46.2%). Antimicrobial minimum inhibitory concentrations were determined by broth micro-dilution and agar-dilution. Based on the susceptibility of each organism, isolates were screened for resistance genes (ß-lactamases and plasmid mediated quinolones resistance determinants) by PCR. Extended-spectrum ß-lactamase producing Enterobacteriaceae and methicillin resistant S. aureus (MRSA) were identified from 6/143 (4.2%) and 2/143 (1.4%) of samples respectively. The qnrB, qnrS and aac(6')-Ib-cr plasmid mediated quinolone resistance determinants were identified in 2/143 (1.4%) of samples tested. None of the Enterobacteriaceae isolates were resistant to meropenem or colistin. Similarly, all Enterococcus isolates remained susceptible to ampicillin, penicillin and vancomycin. Finding multi-drug resistant bacteria which are frequently isolated from human infections is concerning, although the contribution of the global food trade to the dissemination of resistance remains cryptic. These results suggest that imported plant-based foods may be an underappreciated source of clinically relevant resistant organisms. Further study is required to address these gaps in our understanding of the epidemiology of resistance, and the magnitude of the risk posed to human health by these organisms.
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Enterobacteriaceae/aislamiento & purificación , Enterococcus/aislamiento & purificación , Staphylococcus aureus Resistente a Meticilina/aislamiento & purificación , Plantas Comestibles/microbiología , Antibacterianos/farmacología , Canadá , Farmacorresistencia Bacteriana Múltiple/genética , Enterobacteriaceae/efectos de los fármacos , Enterobacteriaceae/genética , Enterococcus/efectos de los fármacos , Enterococcus/genética , Frutas/microbiología , Humanos , Staphylococcus aureus Resistente a Meticilina/efectos de los fármacos , Staphylococcus aureus Resistente a Meticilina/genética , Pruebas de Sensibilidad Microbiana , Plásmidos/genética , Quinolonas/farmacología , Especias/microbiología , Verduras/microbiología , beta-Lactamasas/genéticaRESUMEN
Dietary intake is a key determinant of gastrointestinal microbiota composition. Studies have considered the relationship between gut microbiota and dietary patterns. It is likely that certain plant foods that contain fiber and other bioactive matter may be more likely to drive microbial changes than others; however, study design and other factors can make interpretation of the literature difficult. Fifteen well-controlled, well-defined diet interventions published between 2008 and 2018 using whole, plant foods were evaluated for their influence on gut microbiota. There was limited effect on microbial diversity across studies and modest microbial changes were noted in 10 of 15 studies. More research is needed before specific plant foods can be recommended to improve gut microbiota and ultimately health. Methodologic considerations for future diet and microbiome studies are discussed. Additional research to better understand how specific whole, plant foods influence microbe composition, functionality, and metabolite production is needed, as are mechanistic studies linking diet-induced gut microbe changes to health.
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Dieta/métodos , Ingestión de Alimentos/fisiología , Microbioma Gastrointestinal , Plantas Comestibles/microbiología , Adulto , Anciano , Fibras de la Dieta/administración & dosificación , Femenino , Humanos , Masculino , Persona de Mediana EdadRESUMEN
Dysregulation of immune responses to environmental antigens by the intestine leads to the chronic inflammatory disease, inflammatory bowel disease (IBD). Recent studies have thus sought to identify a dietary component that can inhibit lipopolysaccharide (LPS)-induced nuclear factor-kappa beta (NF-κB) signaling to ameliorate IBD. This study assessed if the lactic acid bacteria (LAB) from kimchi, suppresses the expression of tumor necrosis factor-alpha (TNF-α) in peritoneal macrophages induced by LPS. Leuconostoc lactis EJ-1, an isolate from LAB, reduced the expression of interleukin-6 (IL-6) and IL-1ß in peritoneal macrophages induced by LPS. The study further tested whether EJ-1 alleviates colitis induced by 2,4,6-trinitrobenzene sulfonic acid (TNBS) in mice. TNBS significantly increased myeloperoxidase (MPO) expression, macroscopic colitis scores, and colon shortening. Oral administration of L. lactis EJ-1 resulted in an inhibited in TNBS-induced loss in body weight, colon shortening, MPO activity, and NF-κB and inducible nitric oxide synthase expression; it also led to a marked reduction in cyclooxygenase-2 expression. L. lactis EJ-1 also inhibited the TNBS-induced expression of TNF-α, IL-1ß, and IL-6; however, it induced the expression of IL-10. The M2 macrophage markers arginase I, IL-10, and CD206 were elevated by EJ-1. Collectively, these results suggest that EJ-1 inhibits the NF-κB signaling and polarizes M1- to M2-macrophage transition, which help in ameliorating colitis.
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Colitis/terapia , Leuconostoc , Lipopolisacáridos/inmunología , Macrófagos Peritoneales/metabolismo , Plantas Comestibles/microbiología , Animales , Colitis/inducido químicamente , Colon/metabolismo , Modelos Animales de Enfermedad , Enfermedades Inflamatorias del Intestino/inmunología , Enfermedades Inflamatorias del Intestino/terapia , Interleucina-10/metabolismo , Interleucina-1beta/metabolismo , Interleucina-6/metabolismo , Leuconostoc/inmunología , Leuconostoc/metabolismo , Lipopolisacáridos/metabolismo , Ratones , FN-kappa B/metabolismo , Transducción de Señal/inmunología , Ácido Trinitrobencenosulfónico/efectos adversosRESUMEN
INTRODUCCIÓN: Los germinados son alimentos listos para el consumo cuyo uso está bastante extendido y de los que es necesario garantizar su inocuidad. OBJETIVOS: Nuestros objetivos fueron conocer la Nor - mativa Europea que regula la Seguridad Alimentaria de los mismos y evaluar la calidad microbiológica de algunos tipos de germinados. METODOLOGÍA: La Normativa Europea estudiada recoge la evolución relativa a la Seguridad Alimentaria de hortalizas, incluyendo las semillas germinadas. En 2005 se establece únicamente la investigación de Salmonella y a partir de 2013 plantea criterios de calidad microbiológica para los germinados; dicha Normativa esta transpuesta a la Reglamentación Española. Para el estudio microbiológico se utilizaron 5 tipos diferentes de germinados adquiridos en el comercio, que se analizaron directamente (control), después de su lavado con agua destilada y tras su tratamiento con un desinfectante. Se realizaron recuentos de bacterias aerobias mesófilas totales, Escherichia coli y Listeria monocytogenes y se investigó la presencia de Salmonella spp. RESULTADOS: Los recuentos de bacterias aerobias mesófilas totales en los controles estuvieron comprendidos entre 1,0 X 108 a 2,0 X 109 ufc/g; en los lavados, fueron de 6,0 X 107 a 1,1 X 109 ufc/g y en los tratados de 1,0 X 107 a 6,8 X 108 ufc/g. La reducción de la carga bacteriana por el lavado fue de 24 % (ajo) a 50 % (brócoli) y en el caso del tratamiento con el desinfectante de 59 % (ajo) a 90 % (alfalfa). Los recuentos de Escherichia coli y Listeria monocytogenes fueron inferiores a 10 ufc/g en todas las muestras y en el caso de Salmonella spp. hubo ausencia en 25 g en todas las muestras analizadas. CONCLUSIONES: Los recuentos de Escherichia coli y Listeria monocytogenes son inferiores a lo indicado en la normativa y no se encontró presencia de Salmonella spp. En conclusión los germinados analizados se consideran alimentos seguros
INTRODUCTION: Sprouts are ready-to-eat foods, and their use is quite widespread, consequently it is necessary to guarantee their safety. OBJECTIVE: The aims of this study were to know the European Regulations about Food Safety of sprouts and to evaluate the microbiological quality of some types of sprouts. METHODS: The European Regulation reflects the evolution related to Food Safety of vegetables, including sprouted seeds. In 2005, only Salmonella was established to be investigated in sprouts, and in 2013, the European Union proposed microbiological quality criteria for sprouts and that Regulation was transposed to the Spanish Regulations. For the microbiological study, five different types of commercial sprouts were chosen; they were directly analyzed (control), after distilled water washing and after treatment with a disinfectant. Total mesophilic aerobic bacteria, Escherichia coli and Listeria monocytogenes were counted and presence of Salmonella spp. was determined. RESULTS: Counts of total mesophilic aerobic bacteria were between 1.0 X 108 to 2.0 X 109 cfu/g in control samples; in the washed ones, from 6.0 X 107 to 1.1 X 109 cfu/g, and, in the treated ones, from 1.0 X 107 to 6.8 X 108 cfu/g. The reduction of bacterial load by washing was from 24 % (garlic) to 50 % (broccoli) and in the case of treatment with the disinfectant from 59 % (garlic) to 90 % (alfalfa). Escherichia coli and Listeria monocytogenes counts were lower than 10 cfu/g in all samples, and there was absence of Salmonella spp. in 25 g of all the samples analyzed. CONCLUSIONS: Escherichia coli and Listeria monocytogenes counts were lower than those indicated in the Regulations, and no presence of Salmonella spp was found. In conclusion, the analyzed sprouts are considered safe and innocuous foods
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Humanos , Abastecimiento de Alimentos/normas , Microbiología de Alimentos/normas , Legislación Alimentaria , Plantas Comestibles/embriología , Plantas Comestibles/microbiología , Listeria monocytogenes/aislamiento & purificación , Escherichia coli/aislamiento & purificación , Salmonella/aislamiento & purificación , Europa (Continente) , Carga BacterianaRESUMEN
Contamination of food during processing is recognized as a main transmission route of Listeria monocytogenes To prevent microbial contamination, biocides are widely applied as disinfectants in food processing plants. However, there are concerns about the development of antimicrobial resistance in foodborne pathogens due to widespread biocide usage. In our study, 93 L. monocytogenes isolates from German food production facilities were (i) tested for biocide and antibiotic susceptibility using broth microdilution assays, (ii) analyzed for links between reduced biocide susceptibility and antibiotic resistance, and (iii) characterized by whole-genome sequencing, including the detection of genes coding for biocide tolerance, antibiotic resistance, and other virulence factors. Fifteen L. monocytogenes isolates were tolerant to benzalkonium chloride (BAC), and genes conferring BAC tolerance were found in 13 of them. Antibiotic resistance was not associated with biocide tolerance. BAC-tolerant isolates were assigned to 6 multilocus sequence type (MLST) clonal complexes, and most of them harbored internalin A pseudogenes with premature stop codons or deletions (n = 9). Our study demonstrated a high genetic diversity among the investigated isolates including genotypes that are frequently involved in human infections. Although in vitro adaptation studies to biocides have raised concerns about increasing cross-resistance to antibiotics, our results do not provide evidence for this phenomenon in field isolates.IMPORTANCE Foodborne pathogens such as L. monocytogenes can persist in food production environments for a long time, causing perennial outbreaks. Hence, bacterial pathogens are able to survive cleaning and disinfection procedures. Accordingly, they may be repeatedly exposed to sublethal concentrations of disinfectants, which might result in bacterial adaptation to these biocides. Furthermore, antibiotic coresistance and cross-resistance are known to evolve under biocide selection pressure in vitro Hence, antimicrobial tolerance seems to play a crucial role in the resilience and persistence of foodborne pathogens in the food chain and might reduce therapeutic options in infectious diseases.
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Antibacterianos/farmacología , Desinfectantes/farmacología , Farmacorresistencia Bacteriana/efectos de los fármacos , Listeria monocytogenes/efectos de los fármacos , Plantas Comestibles/microbiología , Compuestos de Benzalconio/farmacología , Microbiología de Alimentos , Genes Bacterianos/genética , Secuenciación de Nucleótidos de Alto Rendimiento , Humanos , Listeria monocytogenes/genética , Listeria monocytogenes/aislamiento & purificación , Pruebas de Sensibilidad Microbiana , Tipificación de Secuencias Multilocus , Estrés Fisiológico/genética , Virulencia/genética , Factores de Virulencia/genética , Secuenciación Completa del GenomaRESUMEN
The plant phyllosphere is colonized by a complex ecosystem of microorganisms. Leaves of raw eaten vegetables and herbs are habitats for bacteria important not only to the host plant, but also to human health when ingested via meals. The aim of the current study was to determine the presence of putative probiotic bacteria in the phyllosphere of raw eaten produce. Quantification of bifidobacteria showed that leaves of Lepidium sativum L., Cichorium endivia L., and Thymus vulgaris L. harbor between 103 and 106 DNA copies per gram fresh weight. Total cultivable bacteria in the phyllosphere of those three plant species ranged from 105 to 108 CFU per gram fresh weight. Specific enrichment of probiotic lactic acid bacteria from C. endivia, T. vulgaris, Trigonella foenum-graecum L., Coriandrum sativum L., and Petroselinum crispum L. led to the isolation of 155 bacterial strains, which were identified as Pediococcus pentosaceus, Enterococcus faecium, and Bacillus species, based on their intact protein pattern. A comprehensive community analysis of the L. sativum leaves by PhyloChip hybridization revealed the presence of genera Bifidobacterium, Lactobacillus, and Streptococcus. Our results demonstrate that the phyllosphere of raw eaten produce has to be considered as a substantial source of probiotic bacteria and point to the development of vegetables and herbs with added probiotic value.
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Bacterias , Microbiología de Alimentos , Plantas Comestibles/microbiología , Probióticos , Técnicas de Tipificación Bacteriana , Bifidobacterium , Biodiversidad , Microbiología Ambiental , Humanos , Lactobacillales , Microbiota , Filogenia , Plantas Medicinales , Verduras/microbiologíaRESUMEN
Investigations into probiotics have focused on their health benefits thus far, with some of the findings finally reaching the food and pharmaceutical industries, which have used them for commercial purposes. In biocontrol research some microbes, mainly isolated from plants, have shown antagonism towards both enteric and plant pathogens, and some of them represent probiotic species. Fresh fruits and vegetables are regarded as health-promoting dietary constituents, and if probiotics could be used to control the pathogens on them then they could turn out to be even healthier. The fresh produce industry still depends on agrochemicals and the increase in the demand for high-priced organically grown produce indicates consumer concerns regarding the use of agrochemicals. If the potential of probiotic organisms to serve as biocontrol agents for fresh produce is exploited, all fresh produce can be made as safe as organically grown produce, and much more wholesome. This review appraises the feasibility of such a move by evaluating how research has progressed in both disciplines (probiotic and biocontrol) and suggests sharing results from research via information technology, efficient collaboration, and the use of novel molecular biological tools to achieve the objective of probiotic antagonists. © 2018 Society of Chemical Industry.
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Enfermedades de las Plantas/prevención & control , Plantas Comestibles/microbiología , Probióticos/farmacología , Microbiología de Alimentos , Frutas/efectos de los fármacos , Frutas/crecimiento & desarrollo , Frutas/microbiología , Lactobacillus/fisiología , Enfermedades de las Plantas/microbiología , Plantas Comestibles/efectos de los fármacos , Plantas Comestibles/crecimiento & desarrollo , Verduras/efectos de los fármacos , Verduras/crecimiento & desarrollo , Verduras/microbiologíaRESUMEN
Microgreens are edible plants used in food preparation for their appealing flavours and colours. They are grown beyond the point of harvest of sprouted seeds, and normally include the cotyledons and first true leaves. Their method of production is similar to sprouted seeds, which is known to be favourable for growth of microbial pathogens, although there is little data on the potential of food-borne pathogens such as Shigatoxigenic Escherichia coli (STEC) to colonise these plants. We found colonisation of nine different species of microgreen plants by STEC (isolate Sakai, stx-), with high levels of growth over five days, of approximately 5 orders of magnitude, for plants propagated at 21⯰C. STEC (Sakai) formed extensive colonies on external tissue, with some evidence for internalisation via stomatal pores. Several factors impacted the level of colonisation: (1) plant tissue type such that for broccoli microgreens, the highest levels of STEC (Sakai) occurred on cotyledons compared to the true leaf and hypocotyl; (2) the route of contamination such that higher levels occurred with contaminated irrigation water compared to direct seed contamination; (3) inoculation dose, although only at low levels of inoculation (3â¯log10) compared to medium (5â¯log10) or high (7â¯log10) levels; (4) environmental factors, including to some extent humidity, but also plant growth substrate types. It was also evident that a starvation response was induced in STEC (Sakai) in low-nutrient plant irrigation medium. Together these data show that microgreens represent a potential hazard of contamination by food-borne pathogens, and to mitigate the risk, they should be considered in the same manner as sprouted seeds.
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Escherichia coli O157/aislamiento & purificación , Contaminación de Alimentos/análisis , Hojas de la Planta/microbiología , Plantas Comestibles/microbiología , Plantones/microbiología , Brassica/microbiología , Recuento de Colonia Microbiana , Escherichia coli O157/crecimiento & desarrollo , Microbiología de Alimentos , Semillas/microbiologíaRESUMEN
BACKGROUND: Aromatic plants may be contaminated with a wide range of microorganisms, making them a potential health hazard when infused or added to ready-to-eat meals. To ensure safety, the effect of gaseous ozone treatment on the population of aerobic plate counts (APC), hygienic indicators (Escherichia coli, Enterococcus spp. and Enterobacteriaceae) and fungi was investigated for five dried aromatic plants: oregano, thyme, mountain tea, lemon verbena and chamomile. Selection, isolation and further fungi identification were based on the phenotypic and macro- and microscopic characteristics. RESULTS: Prior to ozonation, APC on five dried aromatic plants was in the range 5-7 log colony-forming units (CFU) g-1 . The APC exhibited a 4 log reduction, from around 6.5 to 2.5 in the case of oregano, and only a 1-2 log reduction for other herbs after 30 or 60 min of 4 ppm gaseous ozone treatment. Enterococcus spp. and E. coli were not detected on any of the tested dried aromatic plants. The fungi counts were 2-4 log CFU g-1 before ozonation. Aspergillus spp, Penicillium spp, Cladosporium spp, Alternaria spp, Fusarium spp., Ulocladium spp. and some unknown fungi were detected on plants before ozone treatment. Aspergillus spp. and/or Penicillium spp. were only detected on mountain tea and thyme plant material after 60 min of ozonation. CONCLUSION: The present study provides information about the efficiency of ozone on the microbial decontamination of dried aromatic plants. Treatment with gaseous ozone at 4 ppm for 30 min in the case of dried oregano and 60 min in the case of chamomile and lemon verbena could be used as alternative disinfection methods. © 2017 Society of Chemical Industry.
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Descontaminación , Alimentos en Conserva/análisis , Plantas Comestibles/microbiología , Manzanilla/microbiología , Descontaminación/métodos , Desecación , Enterobacteriaceae/aislamiento & purificación , Enterococcus/aislamiento & purificación , Escherichia coli/aislamiento & purificación , Hongos/aislamiento & purificación , Origanum/microbiología , Ozono/farmacologíaRESUMEN
Spices and herbs have been used since ancient times as flavor and aroma enhancers, colorants, preservatives, and traditional medicines. There are more than 30 spices and herbs of global economic and culinary importance. Among the spices, black pepper, capsicums, cumin, cinnamon, nutmeg, ginger, turmeric, saffron, coriander, cloves, dill, mint, thyme, sesame seed, mustard seed, and curry powder are the most popular spices worldwide. In addition to their culinary uses, a number of functional properties of aromatic herbs and spices are also well described in the scientific literature. However, spices and herbs cultivated mainly in tropic and subtropic areas can be exposed to contamination with toxigenic fungi and subsequently mycotoxins. This review provides an overview on the mycotoxin risk in widely consumed spices and aromatic herbs.
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Contaminación de Alimentos , Salud Global , Micotoxinas/toxicidad , Especias/análisis , Alimentación Animal/análisis , Alimentación Animal/microbiología , Alimentación Animal/toxicidad , Bienestar del Animal , Animales , Contaminación de Alimentos/prevención & control , Humanos , Legislación Alimentaria , Micotoxinas/análisis , Componentes Aéreos de las Plantas/química , Componentes Aéreos de las Plantas/crecimiento & desarrollo , Componentes Aéreos de las Plantas/microbiología , Componentes Aéreos de las Plantas/toxicidad , Plantas Comestibles/química , Plantas Comestibles/crecimiento & desarrollo , Plantas Comestibles/microbiología , Plantas Comestibles/toxicidad , Plantas Medicinales/química , Plantas Medicinales/crecimiento & desarrollo , Plantas Medicinales/microbiología , Plantas Medicinales/toxicidad , Rizoma/química , Rizoma/crecimiento & desarrollo , Rizoma/microbiología , Rizoma/toxicidad , Semillas/química , Semillas/crecimiento & desarrollo , Semillas/microbiología , Semillas/toxicidad , Especias/efectos adversos , Especias/normasRESUMEN
A food ethnobotanical field study was conducted among the Gorani of South Kosovo, a small ethnic minority group that speaks a South-Slavic language and lives in the south of the country. We conducted forty-one semi-structured interviews in ten villages of the Kosovar Gora mountainous area and found that seventy-nine wild botanical and mycological taxa represent the complex mosaic of the food cultural heritage in this population. A large portion of the wild food plant reports refer to fermented wild fruit-based beverages and herbal teas, while the role of wild vegetables is restricted. A comparison of these data with those previously collected among the Gorani living in nearby villages within the territory of Albania, who were separated in 1925 from their relatives living in present-day Kosovo, shows that approximately one third of the wild food plant reports are the same. This finding demonstrates the complex nature of Kosovar Gorani ethnobotany, which could indicate the permanence of possible "original" Gorani wild plant uses (mainly including wild fruits-based beverages), as well as elements of cultural adaptation to Serbian and Bosniak ethnobotanies (mainly including a few herbal teas and mushrooms).
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Dieta , Suplementos Dietéticos , Preferencias Alimentarias , Plantas Comestibles/crecimiento & desarrollo , Población Blanca , Adulto , Agaricales/crecimiento & desarrollo , Anciano , Anciano de 80 o más Años , Altitud , Comparación Transcultural , Dieta/etnología , Dieta/tendencias , Etnobotánica , Femenino , Alimentos Fermentados/microbiología , Preferencias Alimentarias/etnología , Jugos de Frutas y Vegetales/microbiología , Humanos , Islamismo , Kosovo , Masculino , Persona de Mediana Edad , Plantas Comestibles/microbiología , Tés de Hierbas , Vida SilvestreRESUMEN
The ecological functions of lactic acid bacteria (LAB) have been utilized in human life for food processing and probiotic therapy. Understanding the interaction mechanisms between LAB and food ingredients may help to clarify the fermentation process and physiological functions of LAB in the production of fermented foods made from plant materials and dairy products. However, the interaction mechanisms have yet to be fully clarified. Although laser diffraction was used for measuring the size changes of aggregates caused by the interaction between LAB and food ingredients, aggregate sizes could not be determined because of the precipitation of aggregates and its disruption from stirring. Therefore, a microscopy-based method for directly visualizing their interactions is required. We directly observed aggregation processes of LAB cells mediated by water-soluble polysaccharides, carboxymethyl cellulose (CMC), by dark-filed microscopy (DFM). DFM could visualize CMC-mediated cell aggregation with high contrast in real time, and revealed that the aggregates were formed by repeated collisions of LAB cells in a suspension. This suggests that our method can be used as a useful assay to directly visualize grain formation caused by interactions between LAB cells and various polysaccharides in food ingredients.
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Adhesión Bacteriana/efectos de los fármacos , Carboximetilcelulosa de Sodio/farmacología , Productos Lácteos/microbiología , Microbiología de Alimentos , Lactobacillales/fisiología , Plantas Comestibles/microbiología , Productos Lácteos/normas , Fermentación , MicroscopíaRESUMEN
A robust, sensitive and reliable ultra fast liquid chromatography combined with electrospray ionization tandem mass spectrometry (UFLC-ESI-MS/MS) was optimized and validated for simultaneous identification and quantification of eleven mycotoxins in medicinal and edible Areca catechu, based on one-step extraction without any further clean-up. Separation and quantification were performed in both positive and negative modes under multiple reaction monitoring (MRM) in a single run with zearalanone (ZAN) as internal standard. The chromatographic conditions and MS/MS parameters were carefully optimized. Matrix-matched calibration was recommended to reduce matrix effects and improve accuracy, showing good linearity within wide concentration ranges. Limits of quantification (LOQ) were lower than 50 µg kg(-1), while limits of detection (LOD) were in the range of 0.1-20 µg kg(-1). The accuracy of the developed method was validated for recoveries, ranging from 85% to 115% with relative standard deviation (RSD) ≤14.87% at low level, from 75% to 119% with RSD ≤ 14.43% at medium level and from 61% to 120% with RSD ≤ 13.18% at high level, respectively. Finally, the developed multi-mycotoxin method was applied for screening of these mycotoxins in 24 commercial samples. Only aflatoxin B2 and zearalenone were found in 2 samples. This is the first report on the application of UFLC-ESI(+/-)-MS/MS for multi-class mycotoxins in A. catechu. The developed method with many advantages of simple pretreatment, rapid determination and high sensitivity is a proposed candidate for large-scale detection and quantification of multiple mycotoxins in other complex matrixes.
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Areca/química , Medicamentos Herbarios Chinos/análisis , Micotoxinas/análisis , Plantas Comestibles/química , Areca/microbiología , Calibración , Cromatografía Liquida/métodos , Límite de Detección , Plantas Comestibles/microbiología , Plantas Medicinales/química , Plantas Medicinales/microbiología , Espectrometría de Masa por Ionización de Electrospray/métodos , Espectrometría de Masas en Tándem/métodosRESUMEN
Plant organic contamination poses a serious threat to the safety of agricultural products and human health worldwide, and the association of endophytic bacteria with host plants may decrease organic pollutants in planta. In this study, we firstly determined the growth response and biofilm formation of endophytic Pseudomonas sp. Ph6-gfp, and then systematically evaluated the performance of different plant colonization methods (seed soaking (SS), root soaking (RS), leaf painting (LP)) for circumventing the risk of plant phenanthrene (PHE) contamination. After inoculation for 48 h, strain Ph6-gfp grew efficiently with PHE, oxalic acid, or malic acid as the sole sources of carbon and energy. Moreover, strain Ph6-gfp could form robust biofilms in LB medium. In greenhouse hydroponic experiments, strain Ph6-gfp could actively colonize inoculated plants internally, and plants colonized with Ph6-gfp showed a higher capacity for PHE removal. Compared with the Ph6-gfp-free treatment, the accumulations of PHE in Ph6-gfp-colonized plants via SS, RS, and LP were 20.1, 33.1, and 7.1 %, respectively, lower. Our results indicate that inoculating plants with Ph6-gfp could lower the risk of plant PHE contamination. RS was most efficient for improving PHE removal in whole plant bodies by increasing the cell numbers of Ph6-gfp in plant roots. The findings in this study provide an optimized method to strain Ph6-gfp reduce plant PAH residues, which may be applied to agricultural production in PAH-contaminated soil.