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1.
Food Chem ; 337: 127767, 2021 Feb 01.
Artigo em Inglês | MEDLINE | ID: mdl-32799162

RESUMO

Egg yolks are a good source of folates. However, the method for analyzing the naturally occurring folates in egg yolks is complicated and time-consuming. In this study, a simplified pre-treatment method followed by validated HPLC-MS/MS was developed to determine native folates in eggs from laying hens treated with different amounts of folic acid. The modified enhanced matrix removal -lipid method to purify samples showed good performance in lipid elimination, reduction of steps and time savings. According to experimental analysis, yolks contained total folate amounts ranging from 147 to 760 µg/100 g when laying hens' diet was supplemented with folic acid from 0 to 10 mg/kg. Four folate vitamers were detected in egg yolks: 5-methyltetrahydrofolate accounted for 91-98% of total folates, whereas folic acid, 5-formyltetrahydrofolate and 10-formylfolic acid together accounted for 2-9%. Therefore, laying hens efficiently converted folic acid in feed into 5-methyltetrahydrofolate in eggs with little folic acid deposition.


Assuntos
Cromatografia Líquida de Alta Pressão , Gema de Ovo/química , Ácido Fólico/análise , Lipídeos/química , Espectrometria de Massas em Tandem , Animais , Galinhas , Suplementos Nutricionais , Feminino , Ácido Fólico/isolamento & purificação , Extração em Fase Sólida , Tetra-Hidrofolatos/análise
2.
Food Chem ; 340: 127960, 2021 Mar 15.
Artigo em Inglês | MEDLINE | ID: mdl-32916403

RESUMO

Folate is a fundamental vitamin for metabolism in plants and humans. A modelling approach has been developed to characterize the reactivity of folates in cowpea seeds during germination at 30 °C, using a water-to-seed ratio of 1:1 (w/w). For this purpose, the concentrations of folic acid, 10-formylfolic acid, 5-methyltetrahydrofolate, 5-formyltetrahydrofolate and tetrahydrofolate were determined in seeds during germination times up to 96 h. Two reaction models were sequentially built and adjusted to experimental data to describe changes in concentration in cowpea seed during two germination phases: before 14 h and after 48 h. Results showed intense enzymatic interconversion of all folate vitamers into 5-methyltetrahydrofolate before 14 h of germination and high enzymatic production of 5-methyltetrahydrofolate, 5-formyltetrahydrofolate and tetrahydrofolate after 48 h of germination. This study suggests that a long germination process could be more beneficial than soaking to increase the production of bioavailable folates within the seed for human consumption.


Assuntos
Ácido Fólico/metabolismo , Germinação , Sementes/crescimento & desenvolvimento , Vigna/crescimento & desenvolvimento , Ácido Fólico/análogos & derivados , Ácido Fólico/análise , Cinética , Modelos Biológicos , Sementes/metabolismo , Temperatura , Tetra-Hidrofolatos/análise , Tetra-Hidrofolatos/metabolismo , Vigna/metabolismo
3.
Klin Lab Diagn ; 65(8): 474-481, 2020 Jul 20.
Artigo em Russo | MEDLINE | ID: mdl-32762188

RESUMO

According to current data, a low level of folic acid (FA) contributes to the progression of arterial hypertension (AH), affecting the metabolism of cells that are involved in the vascular tone regulation, such as hypothalamic astrocytes of nervous tissue. It is also known that the level of FA in the nervous tissue and cerebrospinal fluid is 2-3 times higher than in plasma. There is another metabolic marker of cardiovascular diseases, the level of plasma homoarginine (hArg). The decrease in the level of plasma hArg is also known as a diagnostic sign. In our study, we established that in patients with AH (n = 60), the level of hArg was almost 2 times lower than in healthy individuals, and in 75% of cases the rate was below 1.80 µM. The insufficiency of FA taking into account its low level in plasma FA, as well as the level of total homocysteine (tHcy) higher than 10.9 µM, was observed in 78% of patients. HArg levels at values less than 1.80 µM corresponded to a statistically significant decrease in FA when its content was less than 13.5 nM. This relationship (r = 0.63, p = 0.020) appears in patients with AH, regardless of the number and severity of target organ damage (TOD). FA and hArg as metabolic markers exhibit various diagnostic capabilities when comparing subgroups of patients without TOD and with multiple TOD. Significant differences fared at an acceptable level (p = 0.007) only for the hArg levels, while for the FA concentrations there was only a trend to decrease. It is possible that metabolic disturbances in the central nervous system that are associated with the necessary to maintain high FA concentration contribute to the development of hypertensive status. The causal relationship of a parallel decrease in hArg and FA levels in patients with AH requires further research.


Assuntos
Ácido Fólico , Homoarginina , Hipertensão , Ácido Fólico/análise , Homoarginina/análise , Humanos
4.
PLoS One ; 15(8): e0216848, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-32764747

RESUMO

Maternal nutritional status influences fetal development and long-term risk for adult non-communicable diseases. However, the underlying mechanisms remain poorly understood. We examined whether biomarkers for metabolism and inflammation during pregnancy were associated with maternal health and with child biomarkers and health at 9-12 years of age in 44 maternal-child dyads from the Supplementation with Multiple Micronutrients Intervention Trial (SUMMIT, ISRCTN34151616) in Lombok, Indonesia. Archived blood for each dyad from maternal enrollment, later in pregnancy, postpartum, and from children at 9-12 years comprised 132 specimens. Multiplex microbead immunoassays were used to quantify vitamin D-binding protein (D), adiponectin (A), retinol-binding protein 4 (R), C-reactive protein (C), and leptin (L). Principal component analysis (PCA) revealed distinct variance patterns, i.e. principal components (PC), for baseline pregnancy, bp.pc1.D↓A↓R↓ and bp.pc2.C↓L↑; combined follow-up during pregnancy and postpartum, dp-pp.pc1.D↑↓A↑R↑↓L↓ and dp-pp.pc2.A↑C↑L↑; and children, ch.pc1.D↑R↑C↑ and ch.pc2.D↓A↑L↑. Maternal multiple micronutrient (MMN) supplementation led to an association of baseline maternal bp.pc2.C↓L↑ with decreased post-supplementation maternal dp-pp.pc2.A↑C↑L↑ (p = 0.022), which was in turn associated with both increased child ch.pc1.D↑R↑C↑ (p = 0.036) and decreased child BMI z-score (BMIZ) (p = 0.022). Further analyses revealed an association between maternal dp-pp.pc1.D↑↓A↑R↑↓L↓ and increased child BMIZ (p = 0.036). Child ch.pc1.D↑R↑C↑ was associated with decreased birth weight (p = 0.036) and increased child BMIZ (p = 0.002). Child ch.pc2.D↓A↑L↑ was associated with increased child BMIZ (p = 0.005), decreased maternal height (p = 0.030) and girls (p = 0.002). A pattern of elevated maternal adiponectin and leptin in pregnancy was associated with increased C-reactive protein, vitamin A, and D binding proteins pattern in children, suggesting biomarkers acting in concert may have qualitative as well as quantitative influence beyond single biomarker effects. Patterns in pregnancy proximal to birth were more associated with child status. In addition, child patterns were more associated with child status, particularly child BMI. MMN supplementation affects maternal biomarker patterns of metabolism and inflammation in pregnancy, and potentially in the child. However, child nutrition conditions after birth may have a greater impact on metabolism and inflammation.


Assuntos
Fenômenos Fisiológicos da Nutrição Materna/fisiologia , Micronutrientes/metabolismo , Estado Nutricional/fisiologia , Adiponectina/análise , Adiponectina/sangue , Adulto , Biomarcadores/sangue , Proteína C-Reativa/análise , Criança , Suplementos Nutricionais , Família , Feminino , Ácido Fólico/análise , Humanos , Indonésia , Recém-Nascido , Inflamação , Leptina/análise , Masculino , Terapia Nutricional/métodos , Gravidez , Proteínas Plasmáticas de Ligação ao Retinol/análise , Vitamina A/análise , Proteína de Ligação a Vitamina D/análise , Proteína de Ligação a Vitamina D/sangue
5.
Food Chem ; 333: 127459, 2020 Dec 15.
Artigo em Inglês | MEDLINE | ID: mdl-32683256

RESUMO

Folates are essential micronutrients for human health. The aim of this study was to evaluate the effects of storage, processing and cooking methods on folate content and identify factors with great influence on folate retention in wheat grains and wheat-based foods. For this, the folate levels of wheat grains after 2-8 months of storage, wheat flours, noodles, fermented dough, steamed bun, and bread were sequentially analyzed. An average of 26% folate loss was observed after eight-month storage in wheat grains. The milling process, with an extraction rate of 70%, led to a severe (71%) folate loss. The folate retention rate in noodles was 78%. Fermentation by yeast production enabled a 1.5-4-fold enhancement of folate levels in steamed bun and bread. Boiling, steaming and baking led to a folate loss of 13%, 16%, and 11%, respectively. These results help to guide industrial/household preparation of wheat-based foods for folate nutrition.


Assuntos
Culinária/métodos , Ácido Fólico/química , Sementes/química , Triticum/química , Pão/análise , Fermentação , Farinha/análise , Ácido Fólico/análise , Manipulação de Alimentos , Armazenamento de Alimentos , Vapor
6.
Food Chem ; 333: 127447, 2020 Dec 15.
Artigo em Inglês | MEDLINE | ID: mdl-32688304

RESUMO

Quantification of the specific folate vitamers to estimate total folate in foods is not standardized. A collaborative study, including eight European laboratories, was conducted in order to determine the repeatability and reproducibility of the method for folate quantification in foods using the plant-origin γ-glutamyl hydrolase as part of the extraction procedure. The seven food samples analyzed represent the food groups; fruits, vegetables, dairy products, legumes, offal, fish, and fortified infant formula. The homogenization step was included, and six folate vitamers were analyzed using LC-MS/MS. Total folate content, expressed as folic acid equivalent, was 17-490 µg/100 g in all samples. Horwitz ratio values were within the acceptable range (0.60-1.94), except for fish. The results for fortified infant formula, a certified reference material (NIST 1869), confirmed the trueness of the method. The collaborative study is part of a standardization project within the Nordic Committee on Food Analysis (NMKL).


Assuntos
Fracionamento Químico/métodos , Ácido Fólico/análise , Análise de Alimentos/métodos , Espectrometria de Massas em Tandem/métodos , Animais , Cromatografia Líquida/métodos , Cromatografia Líquida/normas , Laticínios/análise , Grão Comestível/química , Produtos Pesqueiros/análise , Análise de Alimentos/normas , Alimentos Fortificados/análise , Frutas/química , Humanos , Lactente , Fórmulas Infantis/análise , Reprodutibilidade dos Testes , Espectrometria de Massas em Tandem/normas , Verduras/química
7.
Proc Natl Acad Sci U S A ; 117(22): 12071-12079, 2020 06 02.
Artigo em Inglês | MEDLINE | ID: mdl-32430324

RESUMO

Lesch-Nyhan disease (LND), caused by a deficient salvage purine pathway, is characterized by severe neurological manifestations and uric acid overproduction. However, uric acid is not responsible for brain dysfunction, and it has been suggested that purine nucleotide depletion, or accumulation of other toxic purine intermediates, could be more relevant. Here we show that purine alterations in LND fibroblasts depend on the level of folic acid in the culture media. Thus, physiological levels of folic acid induce accumulation of 5-aminoimidazole-4-carboxamide riboside 5'-monophosphate (ZMP), an intermediary of de novo purine biosynthetic pathway, and depletion of ATP. Additionally, Z-nucleotide derivatives (AICAr, AICA) are detected at high levels in the urine of patients with LND and its variants (hypoxanthine-guanine phosphoribosyltransferase [HGprt]-related neurological dysfunction and HGprt-related hyperuricemia), and the ratio of AICAr/AICA is significantly increased in patients with neurological problems (LND and HGprt-related neurological dysfunction). Moreover, AICAr is present in the cerebrospinal fluid of patients with LND, but not in control individuals. We hypothesize that purine alterations detected in LND fibroblasts may also occur in the brain of patients with LND.


Assuntos
Ácido Fólico/análise , Síndrome de Lesch-Nyhan/etiologia , Purinas/metabolismo , Trifosfato de Adenosina/metabolismo , Aminoimidazol Carboxamida/análogos & derivados , Aminoimidazol Carboxamida/metabolismo , Técnicas de Cultura de Células , Meios de Cultivo Condicionados/química , Fibroblastos/metabolismo , Humanos , Hipoxantina Fosforribosiltransferase/metabolismo , Síndrome de Lesch-Nyhan/metabolismo , Ribonucleotídeos/metabolismo
8.
South Med J ; 113(4): 156-163, 2020 04.
Artigo em Inglês | MEDLINE | ID: mdl-32239227

RESUMO

OBJECTIVES: Studies have examined the association between tobacco use and folate levels in pregnancy, yet few have assessed this relation using objective and accurate measures of both smoking and folate. In this study, we evaluated the association between maternal cotinine levels and periconceptional red blood cell (RBC) folic acid reserves in a cohort of low-income pregnant mothers. METHODS: Smoking information, based on salivary cotinine, a highly sensitive and specific tobacco smoke exposure biomarker, was used. Furthermore, folate was assessed using RBC folate, an indicator of long-term folate storage. Participants were early to mid-trimester pregnant women who received antenatal care between 2011 and 2015 at the Genesis Clinic of Tampa (Florida). A total of 496 women were enrolled in the study. Associations between smoking status/maternal salivary cotinine concentrations, sociodemographic factors, and folate concentrations were investigated using Tobit regression analyses. RESULTS: The mean folate level of the participants was 718.3 ± 183.2 ng/mL, and only 2 (0.4%) participants were deficient in folate. We observed no significant difference in folate levels by smoking status. In contrast, salivary cotinine levels were significantly associated with decreased RBC folate concentrations (ß -11.43, standard error 5.45, P = 0.032). Prepregnancy maternal body mass index, gestational age, stress, and depression also were associated with folate levels. CONCLUSIONS: Low RBC folate is associated with perinatal factors, including high maternal cotinine levels, body mass index, stress, and depression. The effect of low folate levels among smokers cannot be overemphasized, considering that tobacco products not only reduce folate levels but also decrease the bioutilization of folate.


Assuntos
Cotinina/análise , Eritrócitos/química , Fertilização/fisiologia , Ácido Fólico/análise , Ácido Fólico/sangue , Adulto , Biomarcadores/análise , Biomarcadores/sangue , Estudos de Coortes , Cotinina/sangue , Feminino , Florida , Humanos , Gravidez , Poluição por Fumaça de Tabaco/análise
9.
PLoS One ; 15(4): e0230583, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-32267871

RESUMO

Folic acid content was evaluated in food preparations containing wheat and corn flour submitted to baking, deep-frying, and steaming. Commercially fortified flours showed the absence of folic acid. Flours with laboratory folic acid fortification showed 487 and 474 µg of folic acid in 100 g of wheat and corn flours, respectively. In the corn flour preparations, the cake had the highest retention (99%) when compared to couscous (97%). Besides, the cake showed higher retention when compared to the wheat flour preparations due to the interactions of the folic acid with the hydrophobic amino acids of the Zein, a protein found in corn. In wheat flour preparations, vitamin retention was 87%, 80% and 57% in bread, cake, and White sauce respectively. These findings relate to the change of the physicochemical properties of food components that occurs during mixing and cooking of the ingredients.


Assuntos
Culinária/métodos , Farinha/análise , Ácido Fólico/análise , Triticum/química , Zea mays/química , Cromatografia Líquida de Alta Pressão
10.
Food Chem ; 320: 126486, 2020 Aug 01.
Artigo em Inglês | MEDLINE | ID: mdl-32208186

RESUMO

A fast, simple, sensitive, and efficient vortex-assisted dispersive liquid-liquid microextraction method (VA-DES-DLME) was developed based on hydrophobic deep eutectic solvent for extraction of folic acid from flour samples followed by HPLC determination. Hydrophobic DES was prepared by mixing amylalcohol as a hydrogen bond donor and methyltriocthylammonium chloride as a hydrogen bond acceptor. Factors affecting DLLME were considered and optimized. In optimal conditions, the calibration curve was linear in the range 5.0-500 ng g-1 with a correlation coefficient higher than 0.99. The limit of detection (LOD) and the limit of quantification (LOQ) were 1.0 and 3.0 ng g-1, respectively. The intra-day and inter-day precision at concentrations of 10 and 100 ng g-1 were less than 8%. Finally, application of the proposed procedure was investigated by folic acid analysis in flour samples and the relative recoveries obtained were acceptable (Recovery ≥ 90%).


Assuntos
Farinha/análise , Ácido Fólico/análise , Microextração em Fase Líquida/métodos , Cromatografia Líquida de Alta Pressão , Interações Hidrofóbicas e Hidrofílicas , Limite de Detecção , Solventes/química
11.
Food Chem ; 319: 126575, 2020 Jul 30.
Artigo em Inglês | MEDLINE | ID: mdl-32172051

RESUMO

A core-shell molecular imprinting fluorescence nanosensor was developed for the ratiometric fluorescence and visual detection of folic acid (FA). The nanosensor was prepared by anchoring imprinting shell on the silica nanoparticles, and embedding the CdTe quantum dots in imprinted shell to provide FA-dependent fluorescence signals. Under the optimum conditions, a favorable linearity relationship between the fluorescence intensities ratio (I449/I619) and the FA concentration over 0.23-113 µM was offered with a detection limit (LOD) of 48 nM. The visual detection for FA was realized by evaluating profuse fluorescence color change from red to pink to purple to final blue. The proposed sensor possessed excellent sensing performances of rapid response, high precision, super sensitivity and selective recognition. Furthermore, endogenous FA was detected in real samples ranging from 37.4 to 265.8 µg/100 g; satisfactory spiked recoveries were obtained within 94.8-104.2%, which conformed to the measurement results by HPLC-UV.


Assuntos
Ácido Fólico/análise , Análise de Alimentos/instrumentação , Análise de Alimentos/métodos , Impressão Molecular/métodos , Compostos de Cádmio/química , Cor , Ácido Fólico/química , Limite de Detecção , Nanopartículas/química , Propilaminas/química , Pontos Quânticos/química , Sensibilidade e Especificidade , Silanos/química , Dióxido de Silício/química , Espectrometria de Fluorescência/instrumentação , Espectrometria de Fluorescência/métodos , Telúrio/química
12.
Food Chem ; 305: 125450, 2020 Feb 01.
Artigo em Inglês | MEDLINE | ID: mdl-31499291

RESUMO

A round robin comparison was performed in order to test the performance of a recently developed LC-MS/MS method for quantification of 6 folate forms. Eighty-nine samples representing the food groups of fruits, vegetables, legumes, cereals, dairy products, meat, and offal were analyzed by two LC-MS/MS methods and a microbiological assay (MA). A plant-origin deconjugase enzyme (Arabidopsis thaliana) for deconjugation of folates (PE-LC-MS/MS), or animal-origin deconjugase (rat serum and chicken pancreas) (AE-LC-MS/MS) was used in the LC-MS/MS methods, each in a single enzymatic step. In contrast, the MA involved tri-enzyme extraction including human plasma as a deconjugase. A significant bias of 17% lower and 25% higher results was found when PE-LC-MS/MS was compared to MA and AE-LC-MS/MS, respectively. The PE-LC-MS/MS provides fast quantification of various folate vitamers and total folate content, which could be a proper substitute to the currently standardized but imprecise and time-consuming microbiological assay in the future.


Assuntos
Ácido Fólico/análise , Espectrometria de Massas em Tandem/métodos , Animais , Galinhas , Cromatografia Líquida de Alta Pressão , Análise de Alimentos , Frutas/metabolismo , Humanos , Proteínas de Plantas/metabolismo , Ratos , Verduras/metabolismo , gama-Glutamil Hidrolase/metabolismo
13.
Food Chem ; 309: 125662, 2020 Mar 30.
Artigo em Inglês | MEDLINE | ID: mdl-31704072

RESUMO

Strawberry cultivar "San Andreas" was grown under ambient (400 ppm CO2, 25 °C) and elevated (950 ppm CO2, 30 °C) growth conditions. The strawberries were subjected to in vitro gastrointestinal digestion and colonic fermentation to examine the accessibility of polyphenols, vitamin C and folates in fresh and frozen fruits using HPLC-UV analyses. Results revealed that elevated CO2 and higher temperature enhanced the amounts of accessible bioactive compounds in strawberries. Bioaccessibility of pelargonidin-3-glucoside increased from 67% to 88% in strawberries grown under elevated growth. Fresh strawberries grown under ambient growth contained 93.09 ±â€¯6.2 µg/100 g folates and 18.55 ±â€¯0.5 mg/100 g vitamin C as bioaccessible fractions under fed state while, elevated growth enhanced soluble folates and vitamin C up to 188.63 ±â€¯7.5 µg/100 g and 30.48 ±â€¯0.3 mg/100 g, respectively. Fresh strawberries contained higher amounts of accessible micronutrients than frozen strawberries, while increased bile contents in intestinal fluid (fed state) facilitated the release of bioactive compounds to gastrointestinal fluid.


Assuntos
Dióxido de Carbono/química , Cromatografia Líquida de Alta Pressão/métodos , Fragaria/metabolismo , Micronutrientes/análise , Antocianinas/metabolismo , Ácido Ascórbico/análise , Dióxido de Carbono/metabolismo , Ácido Fólico/análise , Fragaria/crescimento & desenvolvimento , Congelamento , Frutas/crescimento & desenvolvimento , Frutas/metabolismo , Polifenóis/análise , Temperatura
14.
Food Chem ; 310: 125935, 2020 Apr 25.
Artigo em Inglês | MEDLINE | ID: mdl-31835228

RESUMO

The determination of targeted healthy compounds in the most popular small and large-scale brewed beer sold in Italy was carried out. Nitrogen compounds, fermentable sugars, total phenolic content and antioxidant capacity, ß-glucans, pyridoxine, folates and silicon were quantified. Further, amine content was determined since raw materials and brewing technology can affect their level. Significantly higher values for total phenolic content, antioxidant activity, nitrogen, folate and putrescine content were found for small scale beers. However, the statistical results were affected by the different beer styles in the small scale and large scale brewed beer groups, since the content of these components can vary between beer styles. Positive Pearson correlation was found between total phenolic content and EBC colour. Wide variations in pyridoxine, ß-glucans and fermentable sugars levels were observed both for small and large scale beers, while average silicon content of two groups was similar.


Assuntos
Antioxidantes/análise , Cerveja/análise , Fenóis/análise , Aminas/análise , Fermentação , Ácido Fólico/análise , Itália , Piridoxina/análise , Silício/análise , Açúcares/análise
15.
J Sci Food Agric ; 100(4): 1694-1701, 2020 Mar 15.
Artigo em Inglês | MEDLINE | ID: mdl-31803938

RESUMO

BACKGROUND: Extreme temperatures are among the primary abiotic stresses that affect plant growth and development. Ascorbic acid (AsA) is an efficient antioxidant for scavenging relative oxygen species accumulated under stress. Folates play a significant role in DNA synthesis and protect plants against oxidative stress. Sweet corn (Zea mays L.), a crop grown worldwide, is sensitive to extreme temperatures at seedling stage, which may cause yield loss. This study was conducted to explore the biosynthetic regulative mechanism of AsA and folates in sweet corn seedlings under temperature stress. RESULTS: The AsA and folate composition and relative gene expression in sweet corn seedlings grown under different temperature stresses (10, 25, and 40 °C) were evaluated. The imposition of temperature stress altered the AsA content mainly by modulating the expression of Zm DHAR, whose encoded enzyme dehydroascorbic reductase (DHAR) is essential in the AsA recycle pathway. Low temperature stress raised the expressions of relative genes, leading to folate accumulation. High temperature stress modulated the folate content by influencing the expression of the correspondence gene for aminodeoxychorismate synthase, Zm ADCS, as well as downstream genes that connected with DNA methylation. CONCLUSION: These results provided a theoretical basis, at a genetic level, for understanding the stress responses mechanism in sweet corn seedlings, offering guidance for sweet corn cultivation. © 2019 Society of Chemical Industry.


Assuntos
Ácido Ascórbico/metabolismo , Ácido Fólico/metabolismo , Zea mays/metabolismo , Ácido Ascórbico/análise , Ácido Fólico/análise , Regulação da Expressão Gênica de Plantas , Estresse Oxidativo , Oxirredutases/genética , Oxirredutases/metabolismo , Proteínas de Plantas/genética , Proteínas de Plantas/metabolismo , Espécies Reativas de Oxigênio/metabolismo , Plântula/química , Plântula/genética , Plântula/metabolismo , Temperatura , Zea mays/química , Zea mays/genética
16.
Spectrochim Acta A Mol Biomol Spectrosc ; 224: 117444, 2020 Jan 05.
Artigo em Inglês | MEDLINE | ID: mdl-31394388

RESUMO

The application of fluorescent carbon dots in bio-imaging has huge positive significance in the field of biomedicine. By taking this advantage, herein we prepared nitrogen, sulfur and iodine doped carbon dots (N,S,I-CDs) by a facile hydrothermal reaction using C3N3S3, potassium iodate (KIO3) and ethylenediamine (EDA), and the obtained N,S,I-CDs show bright blue fluorescence with a high fluorescence quantum yield of about 32.4%. The prepared N, S, I-CDs could interact with the folic acid (FA) with high selectivity, lead to development of a high sensitive method for the FA detection from 0.1 to 175 µM wide linear range with a detection limit of 84 nM (S/N = 3) and also applied them in U-2 OS cells imaging. Moreover, this sensor possessed a good sensitivity, linearity and reversibility in the temperature range of 10-80 °C, and successfully applied for the temperature sensing in cell HT-29 samples. This investigation illustrates that as-prepared N, S, I-CDs probe may have great potential as a high-performance platform for the accurate recognition of temperature in cells and could provide a new tool for the detection of FA in cells.


Assuntos
Técnicas Biossensoriais/métodos , Técnicas Citológicas/métodos , Ácido Fólico/análise , Pontos Quânticos/química , Linhagem Celular Tumoral , Transferência Ressonante de Energia de Fluorescência/métodos , Humanos , Iodo/química , Nitrogênio/química , Enxofre/química , Temperatura
17.
Mikrochim Acta ; 187(1): 33, 2019 12 09.
Artigo em Inglês | MEDLINE | ID: mdl-31814085

RESUMO

In this study, a solution-processing based galvanic deposition approach is described for in-situ deposition of gold nanoparticles (AuNP) on delaminated titanium Ti3C2Tx nanosheets under ultrasonication. The nanocomposite (AuNP@Ti3C2Tx) was placed on a glassy carbon electrode (GCE) and then applied to electrochemically with label-free, and simultaneously sense uric acid (UA), and folic acid (FA) at physiological pH. The modified GCE has attractive figures of merit: (i) The working potentials for UA and AA are well separated (+0.35 V and 0.70 V vs. Ag|AgCl); (ii) wide linear responses (from 0.03-1520 µM for UA and from 0.02-3580 µM for FA; (iii) good electrochemical sensitivities for both UA and FA (0.53 and 0.494 µAµM-1.cm-2, respectively), and (iv) detection limits of 11.5 nM (UA) and 6.20 nM (FA). The electrode exhibited good repeatability (RSD = 4.4%), acceptable reproducibility (RSD = 4.1%), and excellent stability (91.8% over one-month storage). The method was applied to analyze spiked serum samples, and modified GCE is shown appreciable recoveries (97.1-98.8% and 96.8-98.0% for UA, and FA, respectively). Graphical abstractA photograph (top left) of colloidal suspension of gold nanoparticles (AuNPs). They were grown on the delaminated titanium carbide Ti3C2Tx MXene nanosheet via galvanic displacement deposition method, and their corresponding a low-resolution transmission electron microscopy micrograph (top right) of AuNP@Ti3C2Tx. The graphical representation of AuNP@Ti3C2Tx drop-casted on glassy carbon electrode (GCE) (bottom left), and their voltammetric measurement were applied in the presence of both uric acid and folic acid with increasing the concentration of both analytes (bottom right).


Assuntos
Técnicas Eletroquímicas , Ácido Fólico/análise , Ouro/química , Nanopartículas/química , Titânio/química , Ácido Úrico/análise , Tamanho da Partícula , Propriedades de Superfície
18.
Nutrients ; 11(11)2019 Nov 18.
Artigo em Inglês | MEDLINE | ID: mdl-31752138

RESUMO

Folate deficiencies are widespread around the world. Promoting consumption of folate-rich foods could be a sustainable option to alleviate this problem. However, these foods are not always available. Cereals, being a staple food, could contribute to folate intake. They are fermented prior to consumption in many African countries, and fermentation can modify the folate content. In Ethiopia, injera is a widely consumed fermented flat bread. The main drivers of its fermentation are lactic acid bacteria (LAB). The aim of this work was to isolate and identify folate-producing LAB from injera fermented dough and to evaluate their ability to increase folate status after depletion in a rat model. Among the 162 strains isolated from 60 different fermentations, 19 were able to grow on a folate-free culture medium and produced 1 to 43 µg/L (24 h, 30 °C incubation). The four highest folate producers belonged to the Lactobacillus plantarum species. The most productive strain was able to enhance folate status after depletion in a rat model, despite the relatively low folate content of the feed supplemented with the strain. Folate-producing L. plantarum strain has potential use as a commercial starter in injera production.


Assuntos
Grão Comestível/microbiologia , Alimentos e Bebidas Fermentados/microbiologia , Ácido Fólico/análise , Lactobacillales/isolamento & purificação , Lactobacillus plantarum/isolamento & purificação , Animais , Pão , Etiópia , Deficiência de Ácido Fólico , Microbiologia de Alimentos , Masculino , Ratos , Ratos Wistar
19.
J Appl Lab Med ; 3(6): 993-1002, 2019 05.
Artigo em Inglês | MEDLINE | ID: mdl-31639690

RESUMO

BACKGROUND: Serum folate forms, and particularly tetrahydrofolate, are sensitive to oxidation. METHODS: Using a repeated measures design, we investigated the stability of folate forms in convenience samples with added ascorbic acid (AA; 5 g/L) analyzed initially and after variable (approximately 1-33 weeks) storage time at -70 °C. We examined the recovery of tetrahydrofolate added at different spiking levels to serum with and without AA (5 g/L). We also assessed the long-term frozen storage stability of folate forms. RESULTS: Repeat analysis produced consistent results with the initial analysis; the mean relative change (95% CI; Lin's concordance correlation between initial and repeat result; sample size) was 0.08% (-0.24% to 0.39%; r c = 0.999; n = 301) for 5-methyltetrahydrofolate, 4.23% (2.44%-6.05%; r c = 0.984; n = 211) for pyrazino-s-triazine derivative of 4α-hydroxy-5-methyltetrahydrofolate (MeFox), -0.22% (-1.90% to 1.49%; r c = 0.986; n = 214) for folic acid, and 1.49% (-2.71% to 5.88%; r c = 0.889; n = 81) for tetrahydrofolate. Linear regression testing for a time trend indicated an estimated average percent change of less than ±5% for samples retested after 4 months: 5-methyltetrahydrofolate P trend = 0.0007, folic acid P trend < 0.0001, MeFox P trend = 0.38, and tetrahydrofolate P trend = 0.0256. The mean ± SD tetrahydrofolate spiking recovery was 96.7% ± 9.4% for serum with added AA, but <50% for serum without added AA. We observed ≤10% loss for most serum folate forms during 4 years of storage at -70 °C. CONCLUSIONS: Serum containing added AA showed acceptable stability of folate forms during repeat analysis from the same vial within 4 months, complete spiking recovery of tetrahydrofolate during sample processing, and long-term frozen storage stability of folate forms.


Assuntos
Ácido Ascórbico/sangue , Ácido Fólico , Manejo de Espécimes/métodos , Técnicas de Laboratório Clínico , Criopreservação/métodos , Ácido Fólico/análise , Ácido Fólico/metabolismo , Humanos , Tamanho da Amostra , Tetra-Hidrofolatos/análise
20.
J Dig Dis ; 20(12): 636-641, 2019 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-31571400

RESUMO

OBJECTIVE: Data on the association between the antioxidant capacity of a diet and the risk of ulcerative colitis (UC) are scarce. This study aimed to assess whether a relationship exists between dietary total antioxidant capacity (TAC) and the odds of UC in Iranian adults. METHODS: In this case-control study, patients with UC and age-matched healthy controls were recruited from a hospital clinic. All participants completed a validated 168-item food frequency questionnaire, the results of which were subsequently used to generate dietary TAC. Ferric reducing-antioxidant power values were used to calculate dietary TAC. RESULTS: Altogether 62 patients with UC and 124 healthy controls were enrolled. UC patients had a higher calorific intake (P < 0.01), and consumed more monounsaturated fatty acids (P < 0.01), vitamin B9 (P < 0.01) and calcium (P = 0.02) compared with healthy controls, while the control group had a higher vitamin C intake than the participants with UC (P < 0.01). In a fully adjusted model, participants who were in the highest quartile of dietary TAC had a lower risk of UC (odds ratio 0.11, 95% confidence interval 0.01-0.73). CONCLUSIONS: A higher dietary TAC score was associated with lower odds of UC in this case-control study. Further elucidation of the role of key dietary elements is now warranted.


Assuntos
Antioxidantes , Colite Ulcerativa , Dieta , Avaliação Nutricional , Adulto , Antioxidantes/análise , Antioxidantes/metabolismo , Cálcio/sangue , Estudos de Casos e Controles , Colite Ulcerativa/sangue , Colite Ulcerativa/diagnóstico , Colite Ulcerativa/epidemiologia , Ingestão de Energia , Ácidos Graxos Monoinsaturados/análise , Feminino , Ácido Fólico/análise , Humanos , Irã (Geográfico)/epidemiologia , Masculino , Pessoa de Meia-Idade , Fatores de Proteção , Medição de Risco , Inquéritos e Questionários
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