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1.
J Nutr ; 154(9): 2696-2706, 2024 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-39019159

RESUMO

BACKGROUND: Green leafy vegetables (GLV) contain inorganic nitrate, an anion with potential prebiotic effects on the oral microbiome. However, it remains unclear whether GLV and pharmacological supplementation [potassium nitrate (PN)] with a nitrate salt induce similar effects on the oral microbiome. OBJECTIVES: This study aimed to compare the effect of GLV with PN supplementation on the oral microbiome composition and salivary biomarkers in individuals with high blood pressure. METHODS: Seventy individuals were randomly allocated to 3 different groups to follow a 5-wk dietary intervention. Group 1 consumed 300 mg/d of nitrate in form of GLV. Group 2 consumed pills with 300 mg/d of PN and low-nitrate vegetables. Group 3 consumed pills with potassium chloride (placebo: PLAC) and low-nitrate vegetables. The oral microbiome composition and salivary biomarkers of oral health were analyzed before and after the dietary intervention. RESULTS: The GLV and PN groups showed similar microbial changes, probably nitrate-dependent, including an increase in the abundance of Neisseria, Capnocytophaga, Campylobacter species, and a decrease in Veillonella, Megasphaera, Actinomyces, and Eubacterium species after the treatment. Increased abundance of Rothia species, and reduced abundance of Streptococcus, Prevotella, Actinomyces, and Mogibacterium species were observed in the GLV group, which could be nitrate-independent. GLV and PN treatments increased salivary pH, but only GLV treatment showed an increase in the salivary buffering capacity and a reduction of lactate. CONCLUSION: The combination of nitrate-dependent and nitrate-independent microbial changes in the GLV group has a stronger effect to potentially improve oral health biomarkers compared with PN.


Assuntos
Biomarcadores , Hipertensão , Microbiota , Boca , Nitratos , Saliva , Humanos , Nitratos/administração & dosagem , Nitratos/farmacologia , Saliva/microbiologia , Saliva/química , Masculino , Feminino , Pessoa de Meia-Idade , Microbiota/efeitos dos fármacos , Boca/microbiologia , Suplementos Nutricionais , Adulto , Verduras , Dieta , Compostos de Potássio
2.
Artigo em Inglês | MEDLINE | ID: mdl-38747471

RESUMO

CONTEXT: The associations of vegetable and potato intakes with type 2 diabetes (T2D) appear to be nuanced, depending on vegetable types and preparation method, respectively. OBJECTIVE: We investigated the associations of total vegetable, vegetable subgroup, and potato intakes with 1) markers of T2D at baseline and 2) incident T2D cumulative over a 12-year follow-up period in Australian adults. METHODS: Using data from the Australian Diabetes, Obesity and Lifestyle Study, intakes of vegetables and potatoes were assessed via a food frequency questionnaire at baseline. Associations between vegetable intake and 1) fasting plasma glucose (FPG), 2-hour post load plasma glucose (PLG), updated homeostasis model assessment of ß-cell function (HOMA2-%ß), HOMA2 of insulin sensitivity (HOMA2-%S), and fasting insulin levels at baseline and 2) cumulative incident T2D at the end of 12-year follow-up were examined using generalized linear and Cox proportional hazards models, respectively. RESULTS: In total, 8,009 participants were included having median age of 52 years, and vegetable intake of 132 g/day. Higher intake of total vegetable, green leafy, yellow/orange/red, and moderate intakes of cruciferous vegetables was associated with lower PLG. Additionally, higher green leafy vegetable intake was associated with lower HOMA2-%ß and serum insulin. Conversely, higher potato fries/chips intakes were associated with higher FPG, HOMA2-%ß, serum insulin, and lower HOMA2-%S. Participants with moderate cruciferous vegetables intake had a 25% lower risk of T2D at the end of 12 years follow-up. CONCLUSIONS: A higher intake of vegetables, particularly green leafy vegetables, may improve while consuming potato fries/chips, but not potatoes prepared in a healthy way, may worsen glucose tolerance and insulin sensitivity. Our findings suggest a nuanced relationship between vegetable subgroups and their impact on glucose tolerance.

3.
Nutr Res ; 126: 58-66, 2024 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-38615632

RESUMO

The Mediterranean-Dietary Approaches to Stop Hypertension (DASH) Intervention for Neurodegenerative Delay (MIND) dietary pattern is associated with reduced cognitive decline and dementia risk. However, the nutrient features that distinguish the MIND from other patterns are unknown. We investigated the relationship between accordance to the MIND pattern and carotenoid intake (phytonutrients hypothesized to confer neuroprotection) relative to the Mediterranean, DASH, and Healthy Eating Index (HEI-2020). We hypothesized that MIND diet accordance would be a stronger predictor of carotenoid intake relative to other diet indices. A total of 396 adults (aged 19-82 years) completed the Dietary History Questionnaire to assess carotenoid intake and adherence to each diet index. Stepwise regressions with adjustment for covariates followed by the Meng's Z-test were used to compare correlation strength between each diet pattern and carotenoid. All diet patterns were positively associated with lutein and zeaxanthin, ß-carotene, α-carotene, and ß-cryptoxanthin (all ßs ≥0.38, Ps <.01). Effect size comparisons revealed that MIND accordance predicted a greater proportion of variance in lutein and zeaxanthin (all Zs ≥ 3.3, Ps < .001) and ß-carotene (all Zs ≥ 2.6, Ps < .01) relative to the Mediterranean, DASH, and HEI-2020. MIND accordance explained a greater proportion of variance in α-carotene (Z = 3.8, P < .001) and ß-cryptoxanthin (Z = 3.6, P < .001) relative to the HEI-2020. MIND diet accordance was disproportionately related to carotenoid intake, indicating the MIND index places greater emphasis on carotenoid-rich foods, particularly those containing lutein, zeaxanthin, and ß-carotene, relative to other diet indices. Future research is needed to define the role of these carotenoids in nutritional interventions for cognitive health.


Assuntos
Carotenoides , Dieta Saudável , Dieta Mediterrânea , Abordagens Dietéticas para Conter a Hipertensão , Humanos , Pessoa de Meia-Idade , Idoso , Masculino , Feminino , Carotenoides/administração & dosagem , Adulto , Idoso de 80 Anos ou mais , Adulto Jovem , Luteína/administração & dosagem , Comportamento Alimentar , beta Caroteno/administração & dosagem , Dieta , Zeaxantinas/administração & dosagem , Padrões Dietéticos
4.
Food Addit Contam Part B Surveill ; 17(2): 129-136, 2024 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-38390717

RESUMO

Pesticides are used in vegetable farming to control pests and diseases, reduce crop losses and improve yield. The study examined pesticide residues in irrigation waters and leafy green vegetables grown in some farming areas in Accra, Ghana. Three types of irrigation water sources (n = 23) and two exotic and four indigenous Ghanaian leafy vegetables (n = 34) from 10 farming areas in Accra, Ghana were collected and examined for 15 organochlorines, 13 organophosphorus and 9 synthetic pyrethroids pesticide residues using the modified QuEChERS procedure. Pesticide residues were detected on 50% (17/34) of the leafy vegetable and 52% (12/23) of the irrigation water samples analysed. Chlorpyrifos and deltamethrin were the most detected pesticide residues in the vegetables and irrigation water. About 26.5% of the vegetables contained pesticide residues exceeding the EU maximum residue limits, so vegetable farmers should be encouraged to comply with appropriate measures on pesticide use to enhance food safety.


Assuntos
Irrigação Agrícola , Contaminação de Alimentos , Resíduos de Praguicidas , Verduras , Gana , Resíduos de Praguicidas/análise , Verduras/química , Irrigação Agrícola/métodos , Contaminação de Alimentos/análise , Humanos , Piretrinas/análise , Nitrilas/análise , Clorpirifos/análise , Poluentes Químicos da Água/análise , Folhas de Planta/química , Compostos Organofosforados/análise
5.
Pathogens ; 12(8)2023 Aug 04.
Artigo em Inglês | MEDLINE | ID: mdl-37623974

RESUMO

Contaminated, raw or undercooked vegetables can transmit parasitic infections. Here, we investigated parasitic contamination of leafy green vegetables sold in local markets in the Tripoli district, Lebanon, during two consecutive autumn seasons (2020-2021). The study involved the microscopic examination of 300 samples of five different types of vegetables (60 samples per type) and used standardized qualitative parasitological techniques for some protozoa and helminths. The results showed that 16.7% (95% interval for p: 12.6%, 21.4%) (50/300) of the vegetable samples were contaminated with at least one parasite. The most frequently detected parasite was Blastocystis spp. (8.7%; 26/300); this was followed in frequency by Ascaris spp. (3.7%; 11/300). Among the different vegetable types, lettuce (23.3%; 14/60) was the most contaminated, while arugula was the least contaminated (11.7%; 7/60). The statistical analysis did not reveal any significant association between the prevalence of parasitic contamination and the investigated risk factors, which included collection date, vegetable type, market storage status, and wetness of vegetables at the time of purchase (p > 0.05). The high prevalence of parasitic contamination also suggested the potential presence of other microbial pathogens. These findings are important because leafy green vegetables are preferentially and heavily consumed raw in Lebanon. Thus, implementing effective measures that target the farm-to-fork continuum is recommended in order to reduce the spread of intestinal pathogens.

6.
Int J Food Microbiol ; 377: 109786, 2022 Sep 16.
Artigo em Inglês | MEDLINE | ID: mdl-35716582

RESUMO

Ready-to-eat (RTE) leafy greens are popular products that unfortunately have been associated with numerous foodborne illness outbreaks. Since the influence of consumer practices is essential for their quality and safety, the objective of this study was to analyze the microbiota of RTE products throughout shelf life during simulated household conditions. Products from different companies were analyzed in terms of plate counts, and resealed and unopened packages were compared. High bacterial loads were found, up to a total plate count of 9.6 log10 CFU/g, and Enterobacteriaceae plate counts up to 6.0 CFU/g on the expiration date. The effect of consumer practice varied, thus no conclusions regarding resealed or unopened bags could be drawn. The tested products contained opportunistic pathogens, such as Enterobacter homaechei, Hafnia paralvei and Pantoea agglomerans. Amplicon sequencing revealed that the relative abundance of major taxonomic groups changed during shelf life; Pseudomonadaceae and Xanthomonadaceae decreased, while Flavobacteriaceae and Marinomonadaceae inceased. Inoculation with E. coli CCUG 29300T showed that the relative abundance of Escherichia-Shigella was lower on rocket than on other tested leafy greens. Inoculation with E. coli strain 921 indicate growth at the beginning of shelf-life time, while E. coli 731 increases at the end, seemingly able to adapt to cold storage conditions. The high levels of live microorganisms, the detection of opportunistic pathogens, and the ability of E. coli strains to grow at refrigeration temperature raise concerns and indicate that the shelf life may be shortened to achieve a safer product. Due to variations between products, further studies are needed to define how long the shelf-life of these products should be, to ensure a safe product even at the end of the shelf-life period.


Assuntos
Escherichia coli , Microbiota , Carga Bacteriana , Contagem de Colônia Microbiana , Contaminação de Alimentos , Microbiologia de Alimentos , Verduras/microbiologia
7.
Hepatol Int ; 16(4): 846-857, 2022 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-35727501

RESUMO

BACKGROUND: Current dietary guidelines generally treat all types of vegetables the same. However, whether specific vegetables are more beneficial or deleterious for preventing chronic liver disease (CLD) remains uncertain. METHODS: We investigated the associations between starchy and non-starchy vegetables and the odds of hepatic steatosis and fibrosis in a US nationwide cross-sectional study. Diet was assessed by the 24-h dietary recalls. Hepatic steatosis and fibrosis were defined based on vibration-controlled transient elastography (TE). Multiple logistic regression was used to estimate odds ratios (ORs) and 95% confidence intervals (CIs). RESULTS: Among 4170 participants with reliable TE test, 1436 were diagnosed with steatosis, 255 with advanced fibrosis. Increased intake of total starchy vegetables was associated with higher odds of steatosis (OR per 1-SD increment 1.11, 95% CI 1.01-1.24) and advanced fibrosis (OR = 1.39, 95% CI 1.15-1.69). Similar positive associations were observed for potatoes. Conversely, intakes of total non-starchy (OR = 0.82, 95% CI 0.71-0.95) and dark-green vegetables (OR = 0.89, 95% CI 0.82-0.97) were inversely associated with steatosis prevalence. Replacing 5% of energy from starchy vegetables (OR = 0.65, 95% CI 0.44-0.97) or potatoes (OR = 0.65, 95% CI 0.43-0.97) with equivalent energy from dark-green vegetables was associated with lower odds of steatosis. CONCLUSIONS: These findings support the recommendation to limit starchy vegetable intake and increase non-starchy vegetable intake in CLD prevention, and provide evidence for the potential health benefit from dietary substitution of non-starchy vegetables for starchy vegetables.


Assuntos
Técnicas de Imagem por Elasticidade , Fígado Gorduroso , Hepatopatia Gordurosa não Alcoólica , Estudos Transversais , Fígado Gorduroso/epidemiologia , Fígado Gorduroso/prevenção & controle , Humanos , Cirrose Hepática/complicações , Cirrose Hepática/epidemiologia , Cirrose Hepática/prevenção & controle , Hepatopatia Gordurosa não Alcoólica/epidemiologia , Verduras
8.
Nutrients ; 14(6)2022 Mar 08.
Artigo em Inglês | MEDLINE | ID: mdl-35334796

RESUMO

The oral microbiota can contribute to the regulation of blood pressure by increasing the availability of nitric oxide through the reduction of nitrate to nitrite, which can be converted into nitric oxide in the stomach and then enter the circulation. It is unclear if the composition of the oral microbiota is different between women who do and do not develop preeclampsia. This study aimed to compare the composition of the buccal microbiota just prior to the development of symptoms at 36 weeks gestation in 12 women who developed late-onset preeclampsia and 24 matched women who remained normotensive throughout pregnancy by 16S rRNA gene amplicon sequencing. The abundance of the nitrate-reducing Veillonella spp V. parvula and V. dispar and a subunit of nitrate reductase narH was compared using real-time PCR. The abundance of bacteria was correlated with maternal blood pressure and dietary intake of nitrate-containing vegetables. The results showed that the abundance of nitrate-reducing bacteria including Veillonella, specifically V. parvula, and Prevotella was reduced in women who developed preeclampsia. Veillonella but not Prevotella abundance was negatively correlated with maternal blood pressure. The dietary intake of nitrate-containing vegetables did not differ between the groups and was not correlated with the abundance of Veillonella. There was no difference in the abundance of the nitrate reductase subunit narH between the groups. These results suggest that the abundance of nitrate-reducing bacteria is reduced in the oral microbiota of women who later develop preeclampsia, indicating a potential pathway for prevention.


Assuntos
Microbiota , Pré-Eclâmpsia , Bactérias/genética , Bactérias/metabolismo , Feminino , Humanos , Microbiota/genética , Nitratos/metabolismo , RNA Ribossômico 16S/genética , RNA Ribossômico 16S/metabolismo
9.
J Food Prot ; 85(1): 122-132, 2022 01 01.
Artigo em Inglês | MEDLINE | ID: mdl-34324673

RESUMO

ABSTRACT: Leafy green vegetables have increasingly been reported as a reservoir of multidrug-resistant pathogenic Enterobacteriaceae, with Shiga toxin-producing Escherichia coli frequently implicated in disease outbreaks worldwide. This study examined the presence and characteristics of antibiotic resistance, diarrheagenic virulence genes, and phylogenetic groupings of E. coli isolates (n = 51) from commercially produced lettuce and spinach from farms, through processing, and at the point of sale. Multidrug resistance was observed in 33 (64.7%) of the 51 E. coli isolates, with 35.7% (10 of 28) being generic and 100% (23 of 23) being extended-spectrum ß-lactamase/AmpC producing. Resistance of E. coli isolates was observed against neomycin (51 of 51, 100%), ampicillin (36 of 51, 70.6%), amoxicillin (35 of 51, 68.6%), tetracycline (23 of 51, 45%), trimethoprim-sulfamethoxazole (22 of 51, 43%), chloramphenicol (13 of 51, 25.5%), Augmentin (6 of 51, 11.8%), and gentamicin (4 of 51, 7.8%), with 100% (51 of 51) susceptibility to imipenem. Virulence gene eae was detected in two E. coli isolates from irrigation water sources only, whereas none of the other virulence genes for which we tested were detected. Most of the E. coli strains belonged to phylogenetic group B2 (25.5%; n = 13), B1 (19.6%; n = 10), and A (17.6%; n = 9), with D (5.9%; n = 3) less distributed. Although diarrheagenic E. coli was not detected, antibiotic resistance in E. coli prevalent in the supply chain was evident. In addition, a clear link between E. coli isolates from irrigation water sources and leafy green vegetables through DNA fingerprinting was established, indicating the potential transfer of E. coli from irrigation water to minimally processed leafy green vegetables.


Assuntos
Infecções por Escherichia coli , Escherichia coli Shiga Toxigênica , Antibacterianos/farmacologia , Farmacorresistência Bacteriana , Lactuca , Testes de Sensibilidade Microbiana , Filogenia , Spinacia oleracea , beta-Lactamases
10.
Molecules ; 26(17)2021 Aug 27.
Artigo em Inglês | MEDLINE | ID: mdl-34500636

RESUMO

The African pumpkin (Momordica balsamina) contains bioactive phenolic compounds that may assist in reducing oxidative stress in the human body. The leaves are mainly consumed after boiling in water for a specific time; this hydrothermal process and conditions of the gastrointestinal tract may affect the presence and bioactivity of phenolics either positively or negatively. In this study, the effects of hydrothermal processing (boiling) and in vitro simulated human digestion on the phenolic composition, bioaccessibility and bioactivity in African pumpkin were investigated in comparison with those of spinach (Spinacia oleracea). A high-resolution ultra-performance liquid chromatography, coupled with diode array detection, quadrupole time-of-flight and mass spectrometer (UPLC-DAD-QTOF-MS) was used to profile phenolic metabolites. Metabolites such as 3-caffeoylquinic acid, 5-caffeoylquinic acid, 3,4-dicaffeoylquinic acid, 3,5-dicaffeoylquinic acid and 4,5-dicaffeoylquinic acid were highly concentrated in the boiled vegetable extracts compared to the raw undigested and all digested samples. The majority of African pumpkin and spinach extracts (non-digested and digested) protected Deoxyribonucleic acid (DNA), (mouse fibroblast) L929 and human epithelial colorectal adenocarcinoma (Caco-2) cells from 2,2'-Azobis(2-methylpropionamidine) dihydrochloride (AAPH)-induced oxidative damage. From these results, the consumption of boiled African pumpkin leaves, as well as spinach, could be encouraged, as bioactive metabolites present may reduce oxidative stress in the body.


Assuntos
Cucurbita/química , Digestão/efeitos dos fármacos , Momordica/química , Fenóis/química , Fenóis/farmacologia , Folhas de Planta/química , Animais , Antioxidantes/química , Células CACO-2 , Linhagem Celular Tumoral , Flavonoides/química , Humanos , Camundongos , Oxirredução/efeitos dos fármacos , Extratos Vegetais/química , Polifenóis/química , Ácido Quínico/análogos & derivados , Ácido Quínico/química , Spinacia oleracea/química , Verduras/química
11.
Int J Food Microbiol ; 354: 109321, 2021 Sep 16.
Artigo em Inglês | MEDLINE | ID: mdl-34225034

RESUMO

Yersiniosis - the 4th most commonly reported zoonosis in the European Union - is caused by the consumption of food contaminated with the bacterium Yersinia enterocolitica. The number of human cases and contaminated food samples is probably underestimated since conventional molecular methods currently proposed for Yersinia enterocolitica detection proved to have several limitations. Critical issues associated with the detection of Yersinia enterocolitica in meat and/or meat product has already been investigated, whereas data on the possible limits of the molecular methods for Yersinia enterocolitica detection in vegetables are still lacking. According to ISO method (ISO 18867:2015), real-time polymerase chain reaction (rtPCR) should be adopted for Yersinia enterocolitica detection, even if it proved to be affected by some biases. Recently, Droplet Digital PCR (ddPCR) has been introduced as a useful tool to detect and quantify different pathogenic bacteria in complex food matrices. However, its potential application for Yersinia enterocolitica detection in vegetables has never been investigated before. In the present study two molecular platforms (rtPCR and ddPCR) were used to evaluate the pathogen's behaviour in experimentally contaminated leafy greens (Lactuca sativa L.) and to assess the rate of detection achievable after the incubation for eleven days at different temperatures. By comparing, noticeable differences emerged between the two technical approaches: only ddPCR allowed the detection of the pathogen in leafy greens when contaminated at low levels. Moreover, results of the present work highlighted the importance of length and temperature of incubation on the survival and/or the growth of Yersinia enterocolitica in vegetables: at 18 and 25 °C the concentration of the pathogen considerably decreases along incubation. Based on data, the use of rtPCR leads to an underestimation of the true prevalence of pathogenic Y. enterocolitica in vegetables, while temperature and time currently proposed for Y. enterocolitica (25 °C for 24 h), allow optimizing detection. To conclude, ddPCR may be undoubtedly proposed as a reliable alternative strategy for the quick detection of the pathogen in food samples.


Assuntos
Microbiologia de Alimentos , Técnicas de Amplificação de Ácido Nucleico , Reação em Cadeia da Polimerase em Tempo Real , Verduras , Yersiniose , Yersinia enterocolitica , Microbiologia de Alimentos/instrumentação , Microbiologia de Alimentos/métodos , Técnicas de Amplificação de Ácido Nucleico/normas , Reação em Cadeia da Polimerase em Tempo Real/normas , Verduras/microbiologia , Yersinia enterocolitica/genética
12.
Appetite ; 162: 105148, 2021 07 01.
Artigo em Inglês | MEDLINE | ID: mdl-33549836

RESUMO

Dark green vegetables (DGVs; e.g., spinach) are a nutrient rich source of essential vitamins and minerals; yet, children's intakes of DGVs fall well below dietary recommendations and creative solutions are needed. This study describes preschoolers (3-5 y) willingness to taste, liking, and intake of fruit-based smoothies containing DGVs (i.e., spinach, collards, kale), commonly referred to as "green smoothies," and explores individual differences in children's eating responses. Using a between-subjects design, preschoolers were randomized to either a FRUIT ONLY smoothie condition (n = 36) or FRUIT+DGV smoothie condition (n = 32). Children's acceptance and intake were collected in one tasting session and one ad libitum snack session, respectively. Parents reported on child food pickiness, food responsiveness, and approach, and children's intake of fruits and DGVs. Children self-reported on previous experience with the study fruits and DGVs. The initial tasting session revealed that the majority of children (84.3%) in the FRUIT+DGV condition willingly tasted all five green smoothies and rated the green smoothies as moderately liked (2.3 ± 0.1). Children in the FRUIT+DGV condition consumed 225.7 ± 31.4 g (9.0 ± 1.3 oz; 1.1 ± 0.2 cups; 91.9 ± 12.9 kcals) of their most preferred green smoothie, providing 18.3 ± 3.7 g (or 0.7 ± 0.1 cups) of DGVs. Children's willingness to try, liking, and intake did not differ by smoothie condition. Individual differences in children's intake are reported. In conclusion, children were willing to try fruit smoothies supplemented with DGVs. Children rated the green smoothies as moderately-liked and children's intake during snack met 31% of their weekly USDA recommendations for DGVs. Adding DGVs to fruit-based smoothies may compliment other effective feeding strategies for increasing children's vegetable consumption.


Assuntos
Preferências Alimentares , Verduras , Pré-Escolar , Dieta , Comportamento Alimentar , Frutas , Humanos , Distribuição Aleatória , Lanches
13.
J Food Prot ; 84(6): 1040-1046, 2021 Jun 01.
Artigo em Inglês | MEDLINE | ID: mdl-33508091

RESUMO

ABSTRACT: Fresh produce-borne enteric bacterial pathogens that are resistant to antibiotics have posed serious challenges to food safety and public health worldwide. This study was conducted to evaluate the antibiotic resistance profiles of Salmonella enterica isolates (n = 33) recovered from exotic and indigenous leafy green vegetable samples (n = 328) collected from 50 vegetable farms in 12 farming areas and 37 vegetable sellers in four market centers in Accra, Ghana, from March 2016 to March 2017 and to determine the distribution of integrons among antibiotic-resistant isolates. The susceptibility of the Salmonella isolates to 12 antibiotics was assayed with the standard disk diffusion assay. The MICs of the five most resisted antibiotics were determined with a twofold macrodilution method. A PCR assay was used to detect the presence of integrons in Salmonella isolates, and PCR products with the amplified integron gene cassette were purified and sequenced with the Sanger sequencing technology. The Salmonella isolates used in the study were resistant to at least one tested antibiotic, and 30.3% (10 of 33) of the isolates were multidrug resistant. Most isolates (81.8%) were resistant to sulfisoxazole. The MICs of tetracycline, cefoxitin, streptomycin, ampicillin, and sulfisoxazole were 16, 32, 64, 64, and >1,024 µg/mL, respectively. Five patterns of multidrug resistance were observed among the Salmonella isolates, and the most common patterns were AAuFox (30.3%) and AAuFoxSSu (18.1%). One (3.0%) of the 33 Salmonella isolates tested positive for the class 1 integron, with a gene cassette of about 800 bp. Nucleotide sequencing revealed that this class 1 integron carried a single gene, dfrA7. Further studies are needed to determine whether the consumption of contaminated leafy green vegetables is a route for acquiring antibiotic-resistant Salmonella in Accra, Ghana.


Assuntos
Salmonella enterica , Antibacterianos/farmacologia , Farmacorresistência Bacteriana Múltipla , Gana , Integrons , Testes de Sensibilidade Microbiana , Verduras
14.
Front Microbiol ; 11: 585690, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-33329455

RESUMO

Indigenous leafy green vegetable crops provide a promising nutritious alternative for East African agriculture under a changing climate; they are better able to cope with biotic and abiotic stresses than cosmopolitan vegetable crops. To verify our hypothesis that the associated microbiome is involved, we studied archaeal and bacterial communities of four locally popular leafy green crops in Uganda (Bidens pilosa, Solanum scabrum, Abelmoschus esculentus, and Gynandropsis gynandra) and of four plant microhabitats (phyllosphere, root endosphere, rhizosphere, and soil) by complementary analyses of amplicon and isolate libraries. All plants shared an unusually large core microbiome, comprising 18 procaryotic families but primarily consisting of Bacillus, Sphingobium, Comamonadaceae, Pseudomonas, and one archaeon from the soil crenarchaeotic group. Microbiome composition did not differ significantly for plant species but differed for microhabitats. The diversity was, in general, higher for bacteria (27,697 ASVs/H = 6.91) than for archaea (2,995 ASVs/H = 4.91); both groups form a robust network of copiotrophic bacteria and oligotrophic archaea. Screening of selected isolates for stress and plant health protecting traits showed that strains of Bacillus and Sphingomonas spp. div. constituted a substantial portion (15-31%) of the prokaryotic plant-associated communities. Across plant species, microbiota were characterized by a high proportion of potential copiotrophic and plant-beneficial species, which was not specific by plant species. The use of identified plant-beneficial isolates could provide the basis for the development of consortia of isolates for both abiotic and biotic stress protection to improve plant and ecosystem health, ensuring food security in East Africa.

15.
Food Res Int ; 137: 109720, 2020 11.
Artigo em Inglês | MEDLINE | ID: mdl-33233289

RESUMO

Solanum nigrum complex (Black nightshade) is a wild leafy vegetable with phenolic antioxidant compounds related to the reduction of oxidative stress. Changes in phenolics and bioactivity due to cooking and gastrointestinal digestion of black nightshade were compared to spinach. Predominant compounds of black nightshade were myricetin, quercetin-3-O-robinoside, 3,4-dicaffeoylquinic acid, 3-caffeoylquinic acid, and rutin, which were improved after boiling but reduced after in vitro digestion. Phenolics were reduced after digestion of black nightshade and spinach; however, bioactivity was still retained, especially in preventing oxidative stress in Caco-2 cells. Hence, indicating their potential to reduce oxidative stress related diseases of the digestive tract.


Assuntos
Solanum nigrum , Antioxidantes , Células CACO-2 , Digestão , Humanos , Fenóis
16.
Int J Mol Sci ; 21(17)2020 Aug 26.
Artigo em Inglês | MEDLINE | ID: mdl-32858866

RESUMO

Fetal membrane dysfunction in response to oxidative stress (OS) is associated with adverse pregnancy outcomes. Nuclear factor (erythroid-derived 2)-like 2 (Nrf2) is one of the regulators of innate OS response. This study evaluated changes in Nrf2 expression and its downstream targets heme oxygenase (HO-1) and peroxisome proliferator-activated receptor gamma (PPARγ) in fetal membranes during OS and infection in vitro. Furthermore, we tested the roles of sulforaphane (SFN; an extract from cruciferous vegetables) and trigonelline (TRN; an aromatic compound in coffee) in regulating Nrf2 and its targets. Fetal membranes (n = 6) collected at term were placed in an organ explant system were treated with water-soluble cigarette smoke extract (CSE), an OS inducer (1:10), and lipopolysaccharide (LPS; 100 ng/mL). Nrf2 expression, expression, its enhancement by sulforaphane (SFN, 10 µM/mL) and down regulation by TRN (10uM/mL) was determined by western blots. Expression of Nrf2 response elements PPARγ (western) heme oxygenase (HO-1), and IL-6 were quantified by ELISA. CSE and LPS treatment of fetal membranes increased nrf2, but reduced HO-1 and PPARγ and increased IL-6. Co-treatment of SFN, but not with TRN, with CSE and LPS increased Nrf2 substantially, as well as increased HO-1 and PPARγ and reduced IL-6 expression. Risk factor-induced Nrf2 increase is insufficient to generate an antioxidant response in fetal membranes. Sulforaphane may enhance innate antioxidant and anti-inflammatory capacity by increasing NRF-2 expression.


Assuntos
Membranas Extraembrionárias/metabolismo , Lipopolissacarídeos/efeitos adversos , Fator 2 Relacionado a NF-E2/metabolismo , Fumaça/efeitos adversos , Regulação para Cima , Alcaloides/farmacologia , Feminino , Regulação da Expressão Gênica/efeitos dos fármacos , Heme Oxigenase-1/metabolismo , Humanos , Interleucina-6/metabolismo , Isotiocianatos/farmacologia , Estresse Oxidativo , PPAR gama/metabolismo , Gravidez , Sulfóxidos , Nicotiana
17.
Front Microbiol ; 11: 638, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-32351477

RESUMO

The increasing occurrence of multidrug-resistant (MDR) extended-spectrum ß-lactamase- (ESBL) and/or AmpC ß-lactamase-producing Enterobacteriaceae in health care systems, the environment and fresh produce is a serious concern globally. Production practices, processing and subsequent consumption of contaminated raw fruit and vegetables represent a possible human transmission route. The purpose of this study was to determine the presence of ESBL/AmpC-producing Enterobacteriaceae in complete spinach supply chains and to characterize the isolated strains phenotypically (antimicrobial resistance profiles) and genotypically (ESBL/AmpC genetic determinants, detection of class 1, 2, and 3 integrons). Water, soil, fresh produce, and contact surface samples (n = 288) from two commercial spinach production systems were screened for ESBL/AmpC-producing Enterobacteriaceae. In total, 14.58% (42/288) of the samples were found to be contaminated after selective enrichment, plating onto chromogenic media and matrix-assisted laser desorption ionization time-of-flight mass spectrometry identity confirmation of presumptive ESBL/AmpC isolates. This included 15.28% (11/72) water and 12.12% (16/132) harvested- and processed spinach, while 25% (15/60) retail spinach samples were found to be contaminated with an increase in isolate abundance and diversity in both scenarios. Dominant species identified included Serratia fonticola (45.86%), Escherichia coli (20.83%), and Klebsiella pneumoniae (18.75%). In total, 48 (81.36%) isolates were phenotypically confirmed as ESBL/AmpC-producing Enterobacteriaceae of which 98% showed a MDR phenotype. Genotypic characterization (PCR of ESBL/AmpC resistance genes and integrons) further revealed the domination of the CTX-M Group 1 ESBL type, followed by TEM and SHV; whilst the CIT-type was the only plasmid-mediated AmpC genetic determinant detected. Integrons were detected in 79.17% (n = 38) of the confirmed ESBL/AmpC-producing isolates, of which we highlight the high prevalence of class 3 integrons, detected in 72.92% (n = 35) of the isolates, mostly in S. fonticola. Class 2 integrons were not detected in this study. This is the first report on the prevalence of ESBL/AmpC-producing Enterobacteriaceae isolated throughout commercial spinach production systems harboring class 1 and/or class 3 integrons in Gauteng Province, South Africa. The results add to the global knowledge base regarding the prevalence and characteristics of ESBL/AmpC-producing Enterobacteriaceae in fresh vegetables and the agricultural environment required for future risk analysis.

18.
Food Microbiol ; 89: 103412, 2020 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-32138983

RESUMO

Pre-harvest testing is increasingly used to enhance the microbial safety of fresh produce. Traditional sampling assumes that sample collectors have no information on potential contamination sources. Knowledge of such factors could potentially increase the effectiveness of pre-harvest sampling programs. Simulation modeling and field validation trials were used to evaluate a hybrid "Samples of Opportunity" (SOO) sampling method that included a portion of the samples based on the sampler's knowledge of risk factors in pre-harvest produce fields. Relative effectiveness of SOO sampling was compared with three traditional sampling methods. These evaluations were based on three non-random contamination scenarios. The mean detection probability of SOO is 96% higher than traditional sampling methods (p < 0.001). However, if the site of actual contamination is offset from assumed area of contamination, the detection probability of SOO sampling drops, and becomes similar or even worse than that achieved by the other sampling methods. Preliminary field validation trials indicated indeed that SOO performed better than the other three sampling methods. This study provides a mathematical approach for evaluating the effectiveness of four pre-harvest sampling methods, and suggests that having a priori knowledge of the contamination source in the field would improve effectiveness of sampling, particularly if done using a standardized protocol.


Assuntos
Bactérias/isolamento & purificação , Simulação por Computador , Contaminação de Alimentos/análise , Inocuidade dos Alimentos , Probabilidade , Microbiologia do Solo
19.
Am J Clin Nutr ; 111(4): 749-756, 2020 04 01.
Artigo em Inglês | MEDLINE | ID: mdl-32091599

RESUMO

BACKGROUND: A diet rich in fruits and vegetables is associated with lowering of blood pressure (BP), but the nutrient(s) responsible for these effects remain unclear. Research suggests that inorganic nitrate present in leafy green vegetables is converted into NO in vivo to improve cardiovascular function. OBJECTIVE: In this study, we evaluated the effect of leafy green vegetables on BP in subjects with elevated BP, with the aim of elucidating if any such effect is related to their high nitrate content. DESIGN: We enrolled 243 subjects, 50-70 y old, with a clinic systolic BP (SBP) of 130-159 mm Hg. After a 2-wk run-in period on a nitrate-restricted diet the subjects were randomly assigned to receive 1 of the following 3 interventions daily for 5 wk: low-nitrate vegetables + placebo pills, low-nitrate vegetables + nitrate pills (300 mg nitrate), or leafy green vegetables containing 300 mg nitrate + placebo pills. The primary end point measure was the difference in change in 24 h ambulatory SBP between the groups. RESULTS: A total of 231 subjects (95%) completed the study. The insignificant change in ambulatory SBP (mean ± standard deviation) was -0.6 ± 6.2 mm Hg in the placebo group, -1.2 ± 6.8 mm Hg in the potassium nitrate group, and -0.5 ± 6.6 mm Hg in the leafy green vegetable group. There was no significant difference in change between the 3 groups. CONCLUSIONS: A 5-wk dietary supplementation with leafy green vegetables or pills containing the same amount of inorganic nitrate does not decrease ambulatory SBP in subjects with elevated BP. This trial was registered at clinicaltrials.gov as NCT02916615.


Assuntos
Pressão Sanguínea , Hipertensão/dietoterapia , Hipertensão/fisiopatologia , Nitritos/metabolismo , Verduras/metabolismo , Idoso , Dieta , Feminino , Humanos , Hipertensão/metabolismo , Masculino , Pessoa de Meia-Idade , Nitritos/análise , Folhas de Planta/química , Folhas de Planta/metabolismo , Verduras/química
20.
Neuropsychiatr Dis Treat ; 15: 3213-3218, 2019.
Artigo em Inglês | MEDLINE | ID: mdl-31819449

RESUMO

BACKGROUND: Emerging evidence has suggested that green vegetables may prevent cognitive decline. METHODS: We examined the cross-sectional association between green vegetables intake and mild cognitive impairment (MCI) using data from 525 participants aged 55 years and above from the China Longitudinal Aging Study (CLAS) in Shanghai. RESULTS: Compared with participants who did not eat green vegetables every day, those who had consumed green vegetables every day had a significantly lower risk of mild cognitive impairment (MCI) (OR = 0.218, 95% CI, 0.116-0.411, p < 0.001), and this association was independent of age, education, having hobbies, surfing the Internet, sleep time per night (youth), long-term residency and consumption of specific red food, such as meat, bread, bean curd, and ginger. CONCLUSION: In summary, using community-based data in Shanghai, we found out that subjects who eat green vegetables every day have significantly lower odds of MCI than those who do not eat every day. Based on current evidence, we propose that eating green vegetables every day might be a potential preventive measure to slow cognitive decline and neurodegeneration in the elderly.

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