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1.
Food Chem ; 398: 133944, 2023 Jan 01.
Artigo em Inglês | MEDLINE | ID: mdl-35987003

RESUMO

B group vitamins, except folate, are involved in at least one step of cellular energy production. Vegetables are considered essential for a healthy diet plan. Vegetables significantly affect diet quality by contributing to the adequate intake of some B group vitamins. Our results demonstrated that the level of vitamins B1, B2, and B3 in the studied vegetables was in the range of 9-85 µg/100 g, 22-319 µg/100 g, and 459-3497 µg/100 g, respectively. However, it is fundamental to investigate the bioaccessibility of all vitamins to identify primary dietary sources. We observed that the average bioaccessibility values for vitamins B1 and B2 were 68.9% and 63.9%, respectively. The bioaccessibility of the nicotinic acid form of vitamin B3 was 40%, while the nicotinamide form was 33.9%. As revealed in this research, the bioaccessibilities of vitamins B1, B2, and B3 in vegetables were generally low in vitro.


Assuntos
Tiamina , Complexo Vitamínico B , Dieta , Ácido Fólico , Tiamina/análise , Verduras
2.
Food Chem ; 398: 133908, 2023 Jan 01.
Artigo em Inglês | MEDLINE | ID: mdl-35988415

RESUMO

Color is the first attribute that influences the acceptance of foods as they become more attractive to consumers when they are more intense and uniform. In recent years, the interest of producers and consumers in purchasing products containing natural ingredients have constantly increased. Natural pigments are commonly extracted from fruits and vegetables, and have been proven to provide health benefits to reduce the risk of diseases such as type-1 diabetes, obesity, and coronary diseases. Additionally, advanced extraction and encapsulation technologies that make food matrices more efficient are useful tools for improving the use of these pigments. In this review, the state-of-the-art of pigments such as carotenoids, anthocyanins, and betalains of plant origin are discussed, including their main sources of production and the factors that affect their physicochemical stability. In addition, different extraction methods are discussed, listing their advantages and disadvantages, and providing some applications of natural pigments in food.


Assuntos
Antocianinas , Betalaínas , Carotenoides , Pigmentação , Verduras
3.
Food Chem ; 398: 133920, 2023 Jan 01.
Artigo em Inglês | MEDLINE | ID: mdl-35988418

RESUMO

The overuse of swelling agents in fruits and vegetables has rapidly increased, resulting in food safety problems. Hence, a new method for the selective extraction and detection of thidiazuron (TDZ) and forchlorfenuron (KT30) was developed using deep eutectic solvent-molecularly imprinted hydrophilic resin (DES-MIHR) as a pipette tip solid-phase extraction (PT-SPE) adsorbent with excellent molecular recognition in aqueous matrixes. DES-MIHR interacted with TDZ and KT30 via π-π interactions and hydrogen bonding. The miniaturized PT-SPE can be performed with just 5.0 mg adsorbent, 0.3 mL water, and 0.2 mL eluent, thus having the advantage of the low consumption of adsorbent and organic reagents. The performance of the DES-MIHR-PT-SPE-high-performance liquid chromatography (HPLC) method was demonstrated with the recoveries from various fruits and vegetables being 81.1-102.9 % (RSD ≤ 7.1 %). Thereby indicating the general applicability of the developed method for the accurate determination of trace swelling agents in fruits and vegetables.


Assuntos
Impressão Molecular , Verduras , Cromatografia Líquida de Alta Pressão , Solventes Eutéticos Profundos , Frutas , Impressão Molecular/métodos , Extração em Fase Sólida/métodos
4.
Food Chem ; 399: 133955, 2023 Jan 15.
Artigo em Inglês | MEDLINE | ID: mdl-36041336

RESUMO

Herbicides atrazine and acetochlor are used in crop production. Because of environmental and health hazards with respective maximum contamination levels of 3 and 20 ng/mL, quantifying these herbicides is important when considering presence in foods and vegetables. We utilized two Pd@Pt nanoparticle-amplified immunoassays, a colorimetric Pd@Pt nanoparticle-linked immunosorbent assay (NLISA) and differential pulse voltammetry (DPV) dependent on catalytic activity of Pd@Pt in a dual-lateral flow immunoassay (dual-LFIA-DPV). We achieved overall recoveries of 88.5-114 % in juice, fruit, and vegetable samples for both immunoassays. The NLISA yielded limits of detection (LODs) of 0.59 and 0.31 µg/kg and the dual-LFIA-DPV 0.27 and 0.51 µg/kg for the two respective species. Results for both immunoassays were validated by high-performance liquid chromatography (HPLC), for all food and drink samples though LODs are compromised when configuring the HPLC for both species with the same chromatogram. We expect Pd@Pt-based immunoassays to prove useful in various fields.


Assuntos
Herbicidas , Nanopartículas , Frutas/química , Herbicidas/análise , Imunoensaio/métodos , Imunoadsorventes/análise , Limite de Detecção , Verduras/química
5.
Spectrochim Acta A Mol Biomol Spectrosc ; 284: 121798, 2023 Jan 05.
Artigo em Inglês | MEDLINE | ID: mdl-36054953

RESUMO

Fenamiphos (Fena), an organophosphorous pesticide, is widely used in agricultural soils to control nematodes and thrips. This nematicide is harmful to fish, birds and humans and, causes several diseases. Therefore, the determination of the nematicide is crucial. Fena has been generally detected by enzyme-based systems which require specific conditions. Herein, we integrated a xanthene moiety and a pyrimidine moiety to obtain an enzyme-free detection system for Fena and, a fluorescent sensor (N-(6-(diethylamino)-9-(pyrimidin-5-yl)-3H-xanthen-3-ylidene)-N-ethylethanaminium hexafluorophosphate(V)) (RosPm) was easily prepared. The colorimetric and spectroscopic properties of RosPm were investigated using the UV-vis and fluorescence spectroscopy. RosPm exhibited a high selectivity and sensitivity to Fena over all the metal ions, the anions and pesticides tested in acetonitrile (ACN)/water (H2O) (v:v, 1:1) solution. RosPm showed a clear visual change from purple to light-purple resulting fluorescent quenching with Fena. This sensor could be preferred for detecting Fena in vegetable samples such as tomato, pepper, and cucumber, and visualizing Fena in living MFC-7 cells.


Assuntos
Compostos Organofosforados , Praguicidas , Verduras , Acetonitrilas , Animais , Ânions , Corantes Fluorescentes/química , Humanos , Íons , Compostos Organofosforados/análise , Praguicidas/análise , Pirimidinas , Solo , Verduras/química , Poluentes Químicos da Água/análise , Xantenos
6.
J Proteomics ; 270: 104739, 2023 Jan 06.
Artigo em Inglês | MEDLINE | ID: mdl-36174954

RESUMO

This study evaluates how long-term dietary low ω6:ω3 ratio in sows and offspring's seaweed (SW) intake affects piglet intestinal function and growth through modifying ileum proteome. Sows were assigned to either control diet (CR, ω6:ω3 ratio = 13:1) or treatment diet (LR, ω6:ω3 = 4:1) during gestation and lactation (n = 8 each). The male weaned offspring were received a basal diet with or without SW powder supplementation (4 g/kg) for 21 days, denoted as SW and CT groups, respectively. In total, four groups of weaned piglets were formed following maternal and offspring's diets combination, represented by CRCT, CRSW, LRCT, and LRSW (n = 10 each). Piglet ileum tissue was collected on day 22 post-weaning and analysed using TMT-based quantitative proteomics. The differentially abundant proteins (n = 300) showed the influence of maternal LR diet on protein synthesis, cell proliferation, and cell cycle regulation. In contrast, the SW diet lowered the inflammation severity and promoted ileal tissue development in CRSW piglets but reduced the fat absorption capacity in LRSW piglets. These results uncovered the mechanism behind the anti-inflammation and intestinal-boosting effects of maternal LR diet in piglets supplemented with SW.


Assuntos
Proteoma , Alga Marinha , Suínos , Animais , Masculino , Feminino , Proteômica , Dieta , Suplementos Nutricionais , Lactação , Íleo , Verduras , Ração Animal/análise
7.
J Proteomics ; 270: 104740, 2023 Jan 06.
Artigo em Inglês | MEDLINE | ID: mdl-36191802

RESUMO

This study examines whether maternal low ω6:ω3 ratio diet and offspring SW supplementation can improve offspring immunity and performance by elucidating the effects on piglet serum proteome. A total of 16 sows were given either a standard (CR, 13:1) or low ω6:ω3 ratio diet (LR, 4:1) during pregnancy and lactation and their male weaned piglets were supplemented with SW powder (4 g/kg, SW) or not (CT) in a 21-day post-weaning (PW) diet. Four PW piglet groups were then identified based on dam and piglet treatment, namely CRCT, CRSW, LRCT, and LRSW (n = 10 each). Piglet serum collected at weaning and d21 PW were analysed (n = 5 each) using TMT-based quantitative proteomics and validated by appropriate assays. The differentially abundant proteins (n = 122) displayed positive effects of maternal LR diet on anti-inflammatory properties and innate immune stimulation. Progeny SW diet activated the innate immunity and enhance the host defence during inflammation. These data demonstrate the value of decreasing ω6:ω3 ratio in maternal diet and SW supplementation in PW piglet's diet to boost their immunity and anti-inflammation properties. SIGNIFICANCE: This novel proteomic study in post-weaned piglets addresses the interplay between maternal and offspring nutritional interventions in a context of rapid and dynamic alterations in piglet metabolic status around weaning. Decreasing ω6:ω3 ratio in maternal diet and SW supplementation in PW piglet's diet can boost their immunity and anti-inflammation properties. This study also provides new insights into piglet serum proteome regulation during post-weaning, a critical development period in swine.


Assuntos
Alga Marinha , Gravidez , Suínos , Animais , Feminino , Masculino , Proteoma , Proteômica , Dieta , Suplementos Nutricionais , Verduras , Ração Animal/análise
8.
Int J Food Microbiol ; 384: 109959, 2023 Jan 02.
Artigo em Inglês | MEDLINE | ID: mdl-36257183

RESUMO

This study evaluated the survival of Listeria monocytogenes on fresh-cut melon and papaya treated with citral nanoemulsion (CN) during 7 days of storage at 4, 8, 12, and 16 °C. CN was prepared by catastrophic phase inversion, and fresh-cut melon and papaya were artificially inoculated, resulting in 5 log cfu/g of L. monocytogenes. Then, they were treated with 0.30 (CN-0.3) and 0.15 (CN-0.15) µL/mL of CN. CN presented droplet size below 200 nm, monodisperse distribution, and negative surface charge. CN-0.3 reduced the L. monocytogenes counts more efficiently, with counts below the detection limit (1 log cfu/g) in both fruits after 48 h at 4 °C, and 72 h at 8 °C and 12 °C. At 16 °C, L. monocytogenes counts were below the detection limit for CN-0.3 after 120 h in papaya, but it survived the other treatments for 7 days. Both CN-0.3 and CN-0.15 decreased the indigenous microbiota. Scanning electron microscopy (SEM) showed bubbles in L. monocytogenes membrane and cell disruption in fruits treated with CN-0.3. Finally, CN-0.3 treated melon and papaya showed greater brightness, herbal flavor and aroma, firmness, and juiciness, as well as lower sugar and organic acid profile changes than the control samples during storage. Results indicate citral nanoemulsion's efficiency in controlling L. monocytogenes growth on fresh-cut melon and papaya stored at refrigerated temperatures without negatively influencing the sensory parameters.


Assuntos
Carica , Cucurbitaceae , Listeria monocytogenes , Microbiologia de Alimentos , Manipulação de Alimentos/métodos , Temperatura , Verduras , Contagem de Colônia Microbiana
9.
Int J Food Microbiol ; 384: 109909, 2023 Jan 02.
Artigo em Inglês | MEDLINE | ID: mdl-36270221

RESUMO

Cassava (Manihot esculenta Crantz) is one of the most widely cultivated foods in the world and is of great socio-economic importance, especially in developing countries. It is predominantly consumed in boiled form, but also is used to produce a number of products, including cassava starch, sour starch, cassava flour and tapioca flour (hydrated cassava starch). Fungal spoilage can occur throughout the production chain, impairing both productivity and quality, as well as posing a potential risk of contamination by mycotoxins. We used multidisciplinary approaches based on phenotypic and molecular data (ITS/BenA/TEF-1a/RPB2 loci) to investigate the mycobiota of 101 samples (including roots, soil and products) collected in the state of São Paulo, Brazil. A total of 20 fungal groups/genera were morphologically characterized, and 37 different species were molecularly identified. The predominant groups in cassava tubers were Fusarium spp., Penicillium spp. and Trichoderma spp. In cassava products, the most frequent groups were Penicillium spp. and Paecilomyces spp. Potentially toxigenic species were also found, including Paecilomyces saturatus, Penicillium citrinum, P. paneum, P. brevicompactum, P. chrysogenum, Fusarium foetens and Fusarium mundagurra. In soil-cultivated cassava samples, the groups found most frequently were Penicillium spp., Cladosporium spp. and Fusarium spp. Some of the species found in cassava tubers and/or product samples were also present in the soil, including F. mundagurra, Neocosmospora solani, P. citrinum and P. brevicompactum. In general, there was a higher occurrence of Penicillium spp., Fusarium spp. and Trichoderma spp., and the predominant species were F. fabacearum and P. citrinum. The mycobiota of Brazilian cassava proved to be extremely diverse, and the occurrence of several species in cassava tubers and/or products are reported herein for the first time. Potentially toxigenic species were found in cassava tubers, cassava products and soil, showing how important it is to constantly monitor these substrates.


Assuntos
Manihot , Micobioma , Brasil , Microbiologia de Alimentos , Verduras , Amido , Solo
10.
J Ethnopharmacol ; 301: 115856, 2023 Jan 30.
Artigo em Inglês | MEDLINE | ID: mdl-36280018

RESUMO

ETNOPHARMACOLOGICAL RELEVANCE: Annona muricata L. (soursop) is traditionally used in the treatment of inflammatory diseases, cancer, and infections caused by fungi. The therapeutic activity explored by its medicinal use is generally associated with its phytoconstituents, such as acetogenins and alkaloids. However, its potential antifungal bioactivity as well as its mechanism of action remains to be established. AIM OF THE STUDY: To evaluate the antifungal activity of the ethanolic extract of A. muricata leaves against multidrug-resistant Candida albicans (ATCC® 10231). MATERIAL AND METHODS: Phytoconstituents were detected by UFLC-QTOF-MS. The minimum inhibitory concentration was determined, followed by the determination of the minimum fungicidal concentration. For planktonic cells, the growth curve and cell density were evaluated. Studies to understand the mechanism of action on the cell envelope involved crystal violet permeability, membrane extravasation, sorbitol protection, exogenous ergosterol binding assay, metabolic activity, and cell viability. Furthermore, mitochondrial membrane potential was assessed. RESULTS: Our analyses demonstrated a significant inhibitory effect of A. muricata, with the ability to reduce fungal growth by 58% and cell density by 65%. The extract affected both the fungal plasma membrane and cell wall integrity, with significant reduction of the cell viability. Depolarization of the fungal mitochondrial membrane was observed after treatment with A. muricata. Rutin, xi-anomuricine, kaempferol-3O-rutinoside, nornuciferine, xylopine, atherosperminine, caffeic acid, asimilobine, s-norcorydine, loliolide, annohexocin, annomuricin, annopentocin, and sucrose were identified as extract bioactive components. CONCLUSIONS: Our findings show that the A. muricata extract is a source of chemical diversity, which acts as a potential antifungal agent with promising application to the therapy of infections caused by C. albicans.


Assuntos
Annona , Annona/química , Candida albicans , Antifúngicos/farmacologia , Antifúngicos/uso terapêutico , Extratos Vegetais/uso terapêutico , Parede Celular , Membrana Celular , Verduras
11.
Food Chem ; 403: 134273, 2023 Mar 01.
Artigo em Inglês | MEDLINE | ID: mdl-36174345

RESUMO

Herein, an ultrasound-assisted dispersive solid phase microextraction (UA-DSPME) approach has been described for trace level analysis of triazole fungicides in real samples. For this purpose, a new nanosorbent was prepared through modification of carboxymethylcellulose biopolymer with zinc-based metal-organic framework and graphene oxide, and fully characterized. Then, the effect of extraction parameters on extraction efficiency was optimized for the microextraction process. Finally, desorbed triazole fungicides with ethanol were determined using gas chromatography equipped with flame ionization detector. This technique provided good linearity (R2 > 0.99), low detection limits (0.3-1.5 ng mL-1), high preconcentration factors (419-426), good relative recoveries (91.6-102 %), and high repeatability (RSD < 4.1 %) at optimized conditions (amount of sorbent: 15 mg; pH of solution: 7.0; and extraction time; 4 min). Ultimately, this approach was applied to determine triazole fungicides in different water and food samples.


Assuntos
Fungicidas Industriais , Microextração em Fase Líquida , Nanocompostos , Microextração em Fase Sólida/métodos , Fungicidas Industriais/análise , Verduras/química , Triazóis/análise , Frutas/química , Água/análise , Celulose/análise , Ultrassom , Nanocompostos/análise , Microextração em Fase Líquida/métodos , Extração em Fase Sólida , Limite de Detecção
12.
Food Chem ; 403: 134315, 2023 Mar 01.
Artigo em Inglês | MEDLINE | ID: mdl-36183466

RESUMO

Sixteen multiparous Holstein cows in four blocks of 4 × 4 Latin square over 4-week experimental periods were used to study the effects of seaweed (Saccharina latissima) supplement (with/without) and protein source (rapeseed meal (RSM)/wheat distiller's grain (WDG)) on milk mineral concentrations. Dietary treatments did not affect milk production and basic composition. Feeding seaweed slightly decreased milk Ca and Cu concentrations; whilst increased (by 3.3-fold) milk iodine (I) concentration, due to a higher dietary I supply. Substitution of WDG with RSM increased feed-to-milk transfer of Ca, Na, and Se and decreased that of Mg, P, Fe, and Mn; but only reduced milk Mn and I concentrations (the latter by 27 % as a potential result of increased glucosinolate intake). Seaweed supplement can improve milk I content when cows' I supply/availability is limited, but care should be taken to avoid excess milk I contents that may pose nutritional risks for young children.


Assuntos
Brassica napus , Brassica rapa , Feófitas , Alga Marinha , Feminino , Bovinos , Animais , Leite/metabolismo , Lactação , Ração Animal/análise , Dieta/veterinária , Suplementos Nutricionais , Grão Comestível , Verduras , Minerais/metabolismo
13.
Food Chem ; 403: 134386, 2023 Mar 01.
Artigo em Inglês | MEDLINE | ID: mdl-36194933

RESUMO

A simple and effective approach to remove pesticide residues on vegetables is necessary for food safety. Ozone microbubbles treatment as an eco-friendly washing technique was investigated for three vegetables (celery, pakchoi and cowpea) collected from the field applied with five pesticides. The removal rates of five pesticide residues on cowpea by ozone microbubbles treatment were 15 %-47 % higher than that by ozone macrobubbles. Moreover, compared with the other four systemic pesticides, emamectin benzoate had a preferable removal rate (65 %-94 %) as a non-systemic pesticide with high water solubility. Through Mass Spectrometry (MS), the double-bonded structure of emamectin benzoate made it more possible to be removed chemically, carrying a degradation rate of 88 % at 25 min in water. Additionally, cowpea showed low removal (28 %-65 %) owing to its stomata and rough surface with SEM. Conclusively, this study demonstrated the potential of the ozone microbubble treatment on pesticide residues removal to enhance food safety.


Assuntos
Ozônio , Resíduos de Praguicidas , Praguicidas , Vigna , Resíduos de Praguicidas/análise , Verduras/química , Microbolhas , Ozônio/química , Praguicidas/análise , Água/análise , Contaminação de Alimentos/análise
14.
Sci Total Environ ; 856(Pt 2): 159141, 2023 Jan 15.
Artigo em Inglês | MEDLINE | ID: mdl-36191706

RESUMO

Rare earth elements (REEs) can cause neoplasms, reduce bone density, affect children's intelligence, etc., and diet is an important way for the human body to absorb REEs. With the increasing use of REEs, the impact on human health is becoming more and more important. So, we used a probabilistic assessment method with Monte Carlo simulation to evaluate the dietary intake of REEs by residents of a large light rare earth mining area in Shandong Province. 16 REEs in 447 samples (including wheat, maize, dry beans, vegetables, fruits and eggs) were detected. The mean value of total REEs for all samples was 286.96 µg/kg, and of light rare earth elements (LREEs) was 270.18 µg/kg. Among of LREEs, Ce, La, Nd and Pr were dominant. The REEs content of different food categories showed that wheat, leafy vegetables and allium vegetables had higher content of REEs, melons vegetables, root vegetables, fruits and eggs had the lowest content. The mean dietary intake of rare earth oxides for the whole population was 4.20 µg/kg bw/d, wheat and vegetables (leafy vegetables, allium vegetables and root vegetables) were the main sources of REEs. Dietary intake estimates of REEs by age and gender did not exceed the acceptable daily intake which means implying no impact on human health.


Assuntos
Metais Terras Raras , Criança , Humanos , Metais Terras Raras/análise , Mineração , Verduras , Nível de Efeito Adverso não Observado , Ingestão de Alimentos , China
15.
Sci Total Environ ; 857(Pt 2): 159507, 2023 Jan 20.
Artigo em Inglês | MEDLINE | ID: mdl-36257421

RESUMO

The proliferation of modern vegetable plastic greenhouses (VPGS) supplies more and more vegetables for food all over the world. The airborne bacteria and fungi induce more exposure opportunities for workers toiling in confined plastic greenhouses. Culture-independent approaches by qPCR and high-throughput sequencing technology were used to study the airborne particulates microbiota in typic VPGS in Shandong, a large base of vegetables in China. The result revealed the mean airborne bacteria concentrations reached 1.67 × 103 cells/m3 (PM2.5) and 2.38 × 103 cells/m3 (PM10), and the mean airborne fungal concentrations achieved 1.49 × 102 cells/m3 (PM2.5) and 3.19 × 102 cells/m3 (PM10) in VPGS. The predominant bacteria in VPGS included Ralstonia, Alcanivorax, Pseudomonas, Bacillus, and Acinetobacter. Botrytis, Alternaria, Fusarium, Sporobolomyces, and Cladosporium were frequently detected fungal genera in VPGS. A higher Chao1 of bacteria in PM10 was significantly different from PM2.5 in VPGS. The potential pathogens in VPGS include Raltonia picketti, Acinetobacter lwoffii, Bacillus anthracis, Botrytis cinerea, and Cladosporium sphaerospermum. The network analysis indicated that airborne microbiota was associated with soil microbiota which was affected by anthropologic activities. The predicted gene functions revealed that bacterial function mainly involved metabolism, neurodegenerative diseases, and fungal trophic mode dominated by Pathotroph-Saprotroph in VPGS. These findings unveiled airborne microbiomes in VPGS so that a strategy for improving air quality can be applied to safeguard health and vegetation.


Assuntos
Microbiologia do Ar , Verduras , Humanos , Plásticos , Fungos , Monitoramento Ambiental , Bactérias , Poeira
16.
Sci Total Environ ; 855: 158587, 2023 Jan 10.
Artigo em Inglês | MEDLINE | ID: mdl-36084778

RESUMO

To explore the responses of soil microbial communities to concentration gradients of antibiotic residues in soil, 32 soil samples were collected from a typical greenhouse vegetable production base in Northern China in 2019. The total concentrations of 26 antibiotic residues in these soil samples was 83.24-4237.93 µg·kg-1, of which metabolites of tetracyclines were 23.34-1798.80 µg·kg-1. The total concentrations in 32 samples were clustered into three levels (L: <100 µg·kg-1, M: 100-300 µg·kg-1, H: >300 µg·kg-1) to elucidate the impacts of antibiotic residues on the diversity, structure, composition, function and antibiotic resistome of soil microbial community. Results showed that higher concentration of antibiotic residues in soil was prone to decrease the diversity and shift the structure and composition of soil microbial community. Antibiotic resistome occurred in soils with antibiotic residues exceeding 300 µg·kg-1. Interactions among soil bacteria followed the order of H > L > M, consistent with the relative abundances of mobile genetic elements. Bacteroidetes and Firmicutes were the top attributors impacting the profile of antibiotics in soil. According to weighted comprehensive pollution index of risk quotient, in 28.1 % of soil samples the residual antibiotics presented high ecological risk, whereas in the rest of soil samples the ecological risk is medium. The results will enrich the database and provide references for antibiotic contamination control in soils of the region and alike.


Assuntos
Microbiota , Poluentes do Solo , Solo , Verduras , Antibacterianos/análise , Esterco , Microbiologia do Solo , Poluentes do Solo/análise , Genes Bacterianos
17.
Spectrochim Acta A Mol Biomol Spectrosc ; 285: 121900, 2023 Jan 15.
Artigo em Inglês | MEDLINE | ID: mdl-36170775

RESUMO

A nanocomposite (UiO-66/Ce-MnO2) was fabricated by combining UiO-66 with cerium-doped manganese dioxide (Ce-MnO2) for colorimetric detecting vitamin C (Vc). Compared with traditional artificial enzymes, the as-synthesized UiO-66/Ce-MnO2 were simple to prepare and did not require the participation of other active substances. The doping of cerium increased the oxygen vacancies and the UiO-66 as a carrier improved the dispersibility. The formation of superoxide anion (O2-) and the inside Ce4+/Ce3+ and Mn4+/Mn3+ redox couples of UiO-66/Ce-MnO2 endowed UiO-66/Ce-MnO2 with a high catalytic capability, which could catalytically oxidize 3, 3', 5, 5'-tetramethylbenzidine (TMB) into oxidation state TMB (oxTMB) without H2O2, accompanying with color change and a prominent peak at 652 nm in UV-vis spectra. Based on the inhibitory effects of Vc on catalytic oxidation of TMB, detection of Vc can be achieved, exhibiting a linear relationship in the concentration of 1.13-17.01 µmol L-1 with a low detection limit of 65.82 nmol L-1. This system can also be detected by smartphone, the linear detection range is 12.47-22.67 µmol L-1. Vc contents in fruits and vegetables detected by the sensor were in good agreement with the 2, 4-Dinitrophenylhydrazine colorimetry method (P > 0.05), indicating a reliable sensor for Vc detection.


Assuntos
Cério , Compostos de Manganês , Oxirredutases , Ácido Ascórbico/análise , Verduras , Óxidos , Frutas/química , Peróxido de Hidrogênio , Colorimetria/métodos , Limite de Detecção
18.
J Hazard Mater ; 443(Pt A): 130162, 2023 02 05.
Artigo em Inglês | MEDLINE | ID: mdl-36257112

RESUMO

Although drinking water is the main source of fluoride intake, recent studies reported that fluoride intake from foods could also be high, depending on cooking methods. In this study, we quantified the fluoride accumulation in foods soaked or boiled in fluoride-containing water and assessed the fluoride intake in different age groups from food and drinking water. We observed that, in the case of rice soaked in fluoride-containing water, more fluoride was accumulated in the rice than previously estimated. Fluoride interferes with the iodine staining process of rice, indicating fluoride adsorption. Fluoride accumulation in rice and vegetables increased when the soaking temperature was raised to 100 °C due to the gelatinization of rice grains and softening of vegetables. Ingesting foods boiled in fluoride-containing water increased the fluoride intake per body weight of infants more significantly than that in children and adults due to their low body weight. These results indicate that soaking and boiling foods in fluoride-containing water significantly increases fluoride intake compared to previous estimations. Therefore, it is necessary to re-evaluate the fluoride intake from food and drinking water considering the methods used for cooking food in each country and region.


Assuntos
Água Potável , Oryza , Criança , Lactente , Adulto , Humanos , Fluoretos , Adsorção , Verduras , Peso Corporal
19.
J Sci Food Agric ; 103(1): 125-134, 2023 Jan 15.
Artigo em Inglês | MEDLINE | ID: mdl-35821573

RESUMO

BACKGROUND: Pretreatments of drying can represent an alternative to minimize the negative aspect process on the dry samples. Thus, the influence of ethanol (ET) and freezing (FG) as drying pretreatments was analyzed for slices of papaya. The slices (5 mm) were submitted for drying kinetics (60 °C and 1.5 m s-1 ). Drying kinetics experimental data were fitted using Page's model and a diffusive model with boundary condition of types I and III. Also the thermophysical properties (thermal conductivity and specific heat) were determined and finally, the kinetics of ultrasound-assisted (40 kHz and 132 W) extraction of total phenolic compounds (TPCs) were realized. RESULTS: The combined method (ET + FG) was more efficient in reducing the drying time of papaya slices (48%) and the model 2 simulating the boundary condition of the third type (type III) showed the best fit to the experimental data. Effective diffusivity and convective coefficient were higher for ET + FG, where the maximum reduction in water content was 91% compared to fresh slices. The pretreatments did not influence the thermal conductivity, however, they were significant in the specific heat and in the extraction of TPCs, being higher in the time of 180 min. CONCLUSION: It was confirmed in the results presented that the combined pretreatment ET + FG is the most viable for drying papaya slices. Furthermore, it was found to be the most efficient in minimizing the loss of TPCs. Therefore, this pretreatment has great potential for application in the development of high value-added foods. © 2022 Society of Chemical Industry.


Assuntos
Carica , Etanol , Congelamento , Dessecação/métodos , Fenóis/química , Verduras
20.
J Sci Food Agric ; 103(1): 389-399, 2023 Jan 15.
Artigo em Inglês | MEDLINE | ID: mdl-35897139

RESUMO

BACKGROUND: The isosteric heat of desorption is vital in evaluating the energy performance of food dryers. The isosteric heat of desorption was investigated for different cassava (Manihot esculenta Crantz) products prepared as flour or starch, with and without fermentation. An automated moisture sorption gravimetric analyser was used to measure the desorption isotherms over 10-90% relative humidity of the drying air at temperatures ranging from 25 to 65 °C. RESULTS: Analysis of variance showed an imperceptible contribution of the preparation method in the measured desorption data. This finding also agreed with microscopical images, which revealed the lack of compelling structural differences among different products. A set of empirical sorption equations suggested by the ASAE standard was examined over the measured desorption isotherms. The standard error of estimation was found to be in the acceptable range of 2.36-3.71%. Furthermore, the fulfilment of the enthalpy-entropy compensation theory was considered as an additional criterion in the thermodynamic results of different sorption equations, besides their fitting adequacy. The modified Chung-Pfost equation has proved to be the most suitable equation for cassava products, as it is capable of reflecting the temperature dependency of the isosteric heat of desorption. The net isosteric heat of desorption obtained was in the range of 540-1110 kJ kg-1 for 0.10 kg kg-1 dry-basis moisture content and 52-108 kJ kg-1 for 0.25 kg kg-1 dry-basis moisture content. CONCLUSION: These findings are technologically relevant for optimising common drying technologies such as flash and flatbed dryers. © 2022 The Authors. Journal of The Science of Food and Agriculture published by John Wiley & Sons Ltd on behalf of Society of Chemical Industry.


Assuntos
Manihot , Manihot/química , Temperatura Alta , Água/análise , Farinha/análise , Temperatura , Verduras
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