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1.
J Sci Food Agric ; 100(4): 1524-1531, 2020 Mar 15.
Artigo em Inglês | MEDLINE | ID: mdl-31769029

RESUMO

BACKGROUND: In recent years, cold-pressed oils have become more and more popular with consumers. However, their oxidative stability is low. Improving the oxidative stability of cold-pressed oils will increase their shelf life. Maillard reaction products (MRPs) have been shown to promote the oxidative stability of lipids. In this study, products from the Maillard reaction of reducing sugars and sesame enzymatically hydrolyzed protein (SEHP) were added to cold-pressed sesame oils to improve their oxidative stability. RESULTS: Three types of MRPs from reducing sugars (xylose, fructose, and glucose) and SEHP were prepared. Xylose-SEHP MRPs prepared under optimum conditions had the highest antioxidant activities among the three. The optimum conditions for xylose-SEHP were as follows: reaction temperature, 130 °C; reaction time, 180 min; pH, 6.5; and sugar/protein ratio, 10:1. The addition of xylose-SEHP MRPs at a level of 20 g kg-1 could significantly improve the oxidative stability of cold-pressed sesame oil. Besides, the addition of MRPs reduced the loss of tocopherol. The interaction of MRPs with endogenous antioxidants in the sesame oil (sesamol and tocopherol) was proved by comparison with lard. There was a synergistic increase in antioxidant activity for the combination of MRPs and sesamol and the combination of MRPs and tocopherol. CONCLUSIONS: The results provide evidence that adding certain MRPs can improve the oxidative stability of cold-pressed sesame oil. © 2019 Society of Chemical Industry.


Assuntos
Manipulação de Alimentos/métodos , Frutose/química , Glucose/química , Produtos Finais de Glicação Avançada/química , Proteínas de Plantas/química , Óleo de Gergelim/química , Sesamum/química , Xilose/química , Aditivos Alimentares/química , Reação de Maillard , Oxirredução
2.
Food Chem ; 305: 125459, 2020 Feb 01.
Artigo em Inglês | MEDLINE | ID: mdl-31520919

RESUMO

In this study the elemental compositions of melanoidin formed at 160 °C from d-glucose (Glc) and l-alanine (Ala) as well as from fructosylalanine - the corresponding Amadori rearrangement product - were compared. Specific chemical bonds were probed by FTIR spectroscopy. This approach tackles the different chemical pathways for melanoidin formation via the Amadori rearrangement in contrast to the reaction from Glc/Ala. Melanoidins formed from fructosylalanine contain about twice as much nitrogen and therefore amino acid as compared to melanoidin from Glc/Ala and exhibit higher absorption in the UV/Vis. Consequently, melanoidins formed from Glc/Ala contain more sugar degradation products with lower absorption due to a smaller size of the conjugated double bond network.


Assuntos
Alanina/análogos & derivados , Alanina/química , Frutose/análogos & derivados , Frutose/química , Glucose/química , Polímeros/química , Frutose/síntese química , Espectroscopia de Ressonância Magnética , Reação de Maillard , Polímeros/metabolismo , Espectroscopia de Infravermelho com Transformada de Fourier , Análise Espectral Raman
3.
Carbohydr Polym ; 228: 115373, 2020 Jan 15.
Artigo em Inglês | MEDLINE | ID: mdl-31635735

RESUMO

Type of sugar and gelling agents used in confectionery formulations have vital importance since they directly influence physicochemical properties during storage. In this study, the effect of a non-caloric rare sugar, D-allulose (formerly called D-psicose) on the starch based confectionery gels were investigated in the presence and absence of soy protein isolate (SPI) using different experimental techniques for 28 days. For characterization of the formulized gel systems, common techniques were used (SEM, DSC, XRD, moisture content, water activity, hardness and color). Time Domain Nuclear Magnetic Resonance (TD-NMR) technique was also employed to explain dynamics in the systems. Sugar type was found to be a very significant factor affecting gel characteristics and retrogradation. Results showed that D-allulose containing formulations were less prone to retrogradation and showed smaller changes upon storage by supporting presence of better gel network. According to X-ray results, sucrose containing formulations were more susceptible to crystallization. T2 relaxation spectra obtained from NMR experiments showed that number of distinct peaks reduced with the addition of SPI while relaxation times of peaks changed when different type of sugar.


Assuntos
Doces , Armazenamento de Alimentos , Frutose/química , Géis/química , Proteínas de Soja/química , Amido/química , Dureza , Água/química
4.
Molecules ; 24(24)2019 Dec 17.
Artigo em Inglês | MEDLINE | ID: mdl-31861157

RESUMO

5-Acetoxymethyl-2-furfural (AMF) was prepared from D-fructose via 1,6-diacetylfructose (DAF) through a simple two-step reaction pathway. Immobilized enzyme (Novozym 435) was found to be the best enzymatic catalyst for the trans-esterification step (yielding 94.6% DAF). In the dehydration step, while soluble H2SO4 was found to be the best acidic catalyst (yielding 86.6% AMF), we opted to utilize heterogeneous cation exchange resin (Amberlyst 15) together with recyclable industrial solvents (1,4-dioxane) for a more sustainable AMF synthesis procedure. Although the total yield of AMF was a little lower, both the enzyme and the solid acid catalyst could be recycled for five cycles without a significant loss of activity, which has a major contribution to the cost-efficient aspect of the entire process.


Assuntos
Resinas de Troca de Cátion/química , Enzimas Imobilizadas , Frutose/química , Furaldeído/química , Lipase/química , Catálise , Desidratação , Esterificação , Solventes/química
5.
Anal Bioanal Chem ; 411(30): 7967-7979, 2019 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-31754770

RESUMO

Naturally occurring fructosamines are of high clinical significance due to their potential use in diabetes mellitus monitoring (quantification of fructosylated hemoglobin, HbA1c) or for the investigation of their reactivity in consecutive reactions and harmfulness towards the organism. Here we report the specific synthesis of the fructosylated dipeptide L-valyl-L-histidine (Fru-Val-His) and fructosylated L-valine (Fru-Val). Both are basic tools for the development and validation of enzymatic HbA1c assays. The two fructosamine derivatives were synthesized via a protected glucosone intermediate which was coupled to the primary amine of Val or Val-His, performing a reductive amination reaction. Overall yields starting from fructose were 36% and 34% for Fru-Val and Fru-Val-His, respectively. Both compounds were achieved in purities > 90%. A HILIC-ESI-MS/MS method was developed for routine analysis of the synthesized fructosamines, including starting materials and intermediates. The presented method provides a well-defined and efficient synthesis protocol with purification steps and characterization of the desired products. The functionality of the fructosylated dipeptide has been thoroughly tested in an enzymatic HbA1c assay, showing its concentration-dependent oxidative degradation by fructosyl-peptide oxidases (FPOX). Graphical abstract.


Assuntos
Diabetes Mellitus/diagnóstico , Frutose/química , Hemoglobina A Glicada/análise , Histidina/química , Cetoses/química , Espectrometria de Massas por Ionização por Electrospray/métodos , Espectrometria de Massas em Tandem/métodos , Valina/química , Ensaios Enzimáticos , Humanos
6.
Eur J Med Chem ; 183: 111720, 2019 Dec 01.
Artigo em Inglês | MEDLINE | ID: mdl-31553933

RESUMO

At present, chemo- and radiotherapies remain to be the mainstream methods for treating triple-negative breast cancer (TNBC), which is known for poor prognosis and high rate of mortality. Two types of novel dual-targeting TNBC liposomes (Fru-RGD-Lip and Fru+RGD-Lip) that actively recognize both fructose transporter GLUT5 and integrin αvß3 were designed and prepared in this work. Firstly, a Y-shaped Fru-RGD-chol ligand, where a fructose and peptide Arg-Gly-Asp (RGD) were covalently attached to cholesterol, was designed and synthesized. Then, the Fru-RGD-Lip was constructed by inserting Fru-RGD-chol into liposomes, while Fru+RGD-Lip was obtained by inserting both Fru-chol and RGD-chol (with the molar ratio of 1:1) into liposomes. The particle size, zeta potential, encapsulation efficiency and serum stability of the paclitaxel-loaded liposomes were characterized. The results indicated that the paclitaxel-loaded Fru-RGD-Lip had the strongest growth inhibition against GLUT5 and αvß3 overexpressed MDA-MB-231 and 4T1 cells. The cellular uptake of Fru-RGD-Lip on MDA-MB-231 cells and 4T1 cells was 3.19- and 3.23-fold more than that of the uncoated liposomes (Lip). The uptake of Fru+RGD-Lip was slightly lower, giving a 2.81- and 2.90-fold increase than that of Lip in two cell lines, respectively. The mechanism study demonstrated that the cellular uptake of both dual-targeting liposomes was likely to be recognized and mediated by GLUT5 and αvß3 firstly, then endocytosed through comprehensive pathways in an energy-dependent manner. Moreover, Fru-RGD-Lip displayed the maximum accumulation, which was 2.62-fold higher than that of Lip for instance, at the tumor sites compared to other liposomes using in vivo imaging. Collectively, the liposomes co-modified by fructose and RGD have enormous potential in the development of targeted TNBC treatment, especially the covalently modified Fru-RGD-Lip, making it a promising multifunctional liposome.


Assuntos
Antineoplásicos Fitogênicos , Transportador de Glucose Tipo 5/metabolismo , Integrina alfaVbeta3/metabolismo , Lipossomos , Paclitaxel , Neoplasias de Mama Triplo Negativas/tratamento farmacológico , Animais , Antineoplásicos Fitogênicos/administração & dosagem , Antineoplásicos Fitogênicos/química , Linhagem Celular Tumoral , Feminino , Frutose/química , Humanos , Lipossomos/química , Camundongos Endogâmicos BALB C , Terapia de Alvo Molecular , Oligopeptídeos/metabolismo , Paclitaxel/administração & dosagem , Paclitaxel/química , Neoplasias de Mama Triplo Negativas/metabolismo
7.
Food Chem ; 300: 125182, 2019 Dec 01.
Artigo em Inglês | MEDLINE | ID: mdl-31326678

RESUMO

Molecular dynamics simulation was performed on sugar profile and moisture content-based mixture systems of six Indian honey samples. Comparative studies were performed to understand the interactive effects of fructose, glucose, sucrose, maltose and water on crystallization. All simulations led to formation of stable crystal but with different interaction energies. Post-simulation analysis showed that Fructose:Glucose of 1.18 formed the most stable crystal with highest van der Waals and electrostatic interactions. The stability of crystal was further validated with least gyration radius (209 ±â€¯1.81 nm2), accessible surface area (4.09 ±â€¯0.04 nm) and root mean square displacement (3.51 ±â€¯0.00261 nm). Results indicated that not only Fructose:Glucose ratio but also sucrose, maltose and water had a significant effect on the overall crystallization process. The simulation data was used to train the artificial neural network which predicted the stability of honey crystallization depending on Fructose:Glucose and Glucose:Water ratios.


Assuntos
Mel , Cristalização , Frutose/química , Glucose/química , Mel/análise , Índia , Maltose/química , Simulação de Dinâmica Molecular , Sacarose/química , Água/química
8.
Carbohydr Res ; 480: 67-72, 2019 Jul 01.
Artigo em Inglês | MEDLINE | ID: mdl-31176192

RESUMO

An improved process for chemical synthesis of l-fructose with high purity in large scale from readily available l-sorbose is described. In general, this synthetic scheme is characterized by inexpensive and easily available starting materials, simple and safe experimental procedures, short time period, low environmental impact, and great potential for scaling up. The scale-up experiment (100 g) was carried out to provide 42.7 g of l-fructose with high HPLC purity of 99.65% in total yield of 50.2%. Consequently, the described improvements would be helpful for those who may wish to use l-fructose and promoting the further evaluation of applications of l-fructose.


Assuntos
Frutose/química , Frutose/síntese química , Configuração de Carboidratos , Técnicas de Química Sintética , Cinética , Modelos Moleculares , Estereoisomerismo
9.
Plant Physiol Biochem ; 141: 477-486, 2019 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-31252253

RESUMO

The induction of leaf injuries, including leaf chlorosis and epinasty, by continuous light in tomato plants is one of the most interesting and mysterious phenomena regarding plant interactions with light, the mechanism of which has not yet been revealed. To gain further insights into this particular response of tomato plants, we cultivated tomato seedlings (Solanum lycopersicum cv. Momotaro) for 14 days under continuous light with different ratios of red and blue light and compared their performance to those grown under continuous or 14/10-h photoperiodic white light using novel methods to quantitatively evaluate the level of leaf chlorosis and epinasty. Continuous monochromatic blue light induced severe chlorosis but almost completely alleviated epinasty in tomato leaf. In contrast, continuous monochromatic red light caused a lower level of leaf chlorosis but very severe epinasty. The combination of red and blue light at different ratios significantly reduced both leaf chlorosis and epinasty under continuous light condition. Carbohydrate contents showed no correlation with leaf chlorosis, while glucose and fructose contents showed correlations with the petiole and leaflet curvatures. Histochemical staining with 3,3'-diaminobenzidine and nitro blue tetrazodium chloride also did not reveal any significant buildup of hydrogen peroxide and superoxide anion in monochromatic blue light treatment. Taken together, these results suggest that chlorosis and epinasty are two distinctive leaf injuries caused by continuous light that may follow very different mechanisms, and an overaccumulation of carbohydrates in the leaf may not be the main cause of continuous light-induced leaf chlorosis in tomato.


Assuntos
Luz , Lycopersicon esculentum/efeitos da radiação , Folhas de Planta/efeitos da radiação , 3,3'-Diaminobenzidina/química , Carboidratos/química , Cor , Frutose/química , Glucose/química , Peróxido de Hidrogênio/química , Lycopersicon esculentum/crescimento & desenvolvimento , Oxigênio/química , Fotoquímica , Fotoperíodo , Fotossíntese , Doenças das Plantas , Proteínas de Plantas/metabolismo , Plântula/metabolismo , Sais de Tetrazólio/química
10.
Arch Biochem Biophys ; 668: 54-60, 2019 06 15.
Artigo em Inglês | MEDLINE | ID: mdl-31091430

RESUMO

The interaction of reducing sugars with proteins leads to the formation of advanced glycation end products (AGE) and reactive oxidative species (ROS). ROS peroxidise free or membrane included unsaturated fatty acids, leading to generate reactive aldehydes as advanced lipid peroxidation end products (ALE). Aldehydes from lipid peroxidation (LPO) react with proteins to cause alteration of protein structure to exacerbate complication of diseases. Here we studied serum albumin glycation in the presence and absence of liposomes as a bio-membrane model to investigate protein structural changes using various techniques including intrinsic and extrinsic fluorescence spectroscopies and electron microscopy analysis. Accordingly, serum albumin glycation and fibrillation were accelerated and intensified in the presence of liposomes through a hypothesized glycation-peroxidation loop (GPL). Together, our results shed light on the necessity of reconsidering diabetic protein glycation to make it close to physiological conditions mimicry, more importantly, proteins structural change due to diabetic glycation is intensified in the proximity of cell membranes which probably potentiates programmed cell death distinct from apoptosis.


Assuntos
Proteínas Amiloidogênicas/metabolismo , Produtos Finais de Glicação Avançada/metabolismo , Multimerização Proteica , Soroalbumina Bovina/metabolismo , 1,2-Dipalmitoilfosfatidilcolina/química , Proteínas Amiloidogênicas/química , Animais , Bovinos , Frutose/química , Produtos Finais de Glicação Avançada/química , Peróxido de Hidrogênio/química , Peroxidação de Lipídeos , Lipossomos/química , Oxirredução , Fosfatidilcolinas/química , Soroalbumina Bovina/química
11.
Int J Biol Macromol ; 133: 702-711, 2019 Jul 15.
Artigo em Inglês | MEDLINE | ID: mdl-31022484

RESUMO

Polysaccharide K4 expressed from E. coli K4 has a similar structure with chondroitin, which can be used as a precursor to produce chondroitin sulfates. Here, we investigated the structure, conformation and biological activity of K4 from an engineered strain with high productivity. The NMR analysis suggested that K4 from wild-type strain with a low yield was a partially fructosylated chondroitin. While K4 from engineered strain was a fully fructosylated chondroitin. Light scattering analysis gave the Mw values of 6.15 × 104, 8.23 × 104 and 1.92 × 104 for K4-1, K4-2 and defructosylated K4 (DK4), respectively. The exponents of functions z1/2 = f(Mw) were in the range of 0.643-0.608, suggesting a random coil conformation for K4 and DK4. And the random coils K4 easily self-assembled into sphere-like aggregates in the dilute aqueous solution. Both K4 and DK4 exhibited significant immunomodulatory activities on RAW 264.7 cells at the dosage range of 5-500 µg/mL.


Assuntos
Condroitina/química , Condroitina/farmacologia , Escherichia coli/genética , Frutose/química , Engenharia Genética , Fatores Imunológicos/química , Fatores Imunológicos/farmacologia , Animais , Configuração de Carboidratos , Proliferação de Células/efeitos dos fármacos , Condroitina/genética , Citocinas/biossíntese , Fatores Imunológicos/metabolismo , Camundongos , Peso Molecular , Óxido Nítrico/biossíntese , Fagocitose/efeitos dos fármacos , Células RAW 264.7
12.
Food Chem ; 289: 285-291, 2019 Aug 15.
Artigo em Inglês | MEDLINE | ID: mdl-30955614

RESUMO

Various metal oxides were used as co-catalysts to improve the production of alkyl lactate over Sn-Beta-P. WO3 exhibited the best promotion effect. The yield of MLA increased from 25% (6.5 g L-1) over Sn-Beta-P (0.2 g) to 52% (13.4 g L-1) over WO3 (0.1 g) and Sn-Beta-P (0.1 g) at 160 °C for 5 h and 3.1 wt% of glucose concentration. MLA yield of 38% was attained even at glucose concentration of 10 wt% and the space-time yield reached 7.1 g L-1 h-1. The action mechanism of WO3 was investigated. Fine WO3 particles adsorbed on surface of Sn-Beta-P in reaction media and decreased the silanol defects of Sn-Beta-P. This promotes retro-aldol of fructose, the rate-determining step of whole reaction, thus facilitated the formation of MLA. Kinetic studies indicate that the presence of WO3 decreased the activation energy of the retro-aldol of fructose. The binary solid WO3 and Sn-Beta-P is recyclable.


Assuntos
Glucose/metabolismo , Ácido Láctico/metabolismo , Óxidos/química , Tungstênio/química , Zeolitas/química , Catálise , Frutose/química , Frutose/metabolismo , Glucose/química , Cinética , Ácido Láctico/análogos & derivados , Estanho/química
13.
Food Chem ; 289: 320-327, 2019 Aug 15.
Artigo em Inglês | MEDLINE | ID: mdl-30955619

RESUMO

The role of Reactive Carbonyl Species (RCS) derived from the Maillard reaction and ascorbic acid degradation on brown color formation was investigated in orange juice during storage. Eight RCS were monitored in aseptic juice over an 8-week period under refrigerated (4 °C) and accelerated conditions (35 °C). Significant changes in RCS concentrations were reported and positively correlated with color formation. Recombination experiments demonstrated the significant role of 3-deoxyglucosone and acetol on color formation as well as their interactions with glyoxal and methylglyoxal that lead to an increase in browning. Isotopic enrichment techniques further identified fructose as the main precursor of RCS, indicating the important role of Maillard reaction as a mechanism of non-enzymatic browning during orange juice storage. Finally, among the amino acids, tryptophan and glutamine showed the largest percentage losses in orange juice during storage and were reported to significantly impact the RCS composition and color formation.


Assuntos
Citrus sinensis/química , Sucos de Frutas e Vegetais/análise , Aminoácidos/análise , Cromatografia Líquida de Alta Pressão , Citrus sinensis/metabolismo , Cor , Desoxiglucose/análogos & derivados , Desoxiglucose/análise , Armazenamento de Alimentos , Frutose/química , Glioxal/análise , Glioxal/química , Reação de Maillard , Espectrometria de Massas , Espectrofotometria Ultravioleta , Temperatura
14.
Food Chem ; 289: 49-55, 2019 Aug 15.
Artigo em Inglês | MEDLINE | ID: mdl-30955640

RESUMO

Stable carbon isotope ratios (δ13C) for glucose, fructose, disaccharides, trisaccharides, and organic acids in 116 commercial honey samples were measured by LC/IRMS. On the basis of EA/IRMS and LC/IRMS authenticity criteria, 39 of the samples were judged to have been adulterated. The δ13C values for organic acids from pure honey, reported here for the first time, ranged from -33.6 to -26.5‰. The mean Δδ13C (glucose-organic acids) value was +3.7 ±â€¯0.9‰. Glucose and organic acid δ13C values were strongly correlated (R = 0.71, P < 0.001). Gluconic acid, the predominant organic acid in honey, has been reported to be produced via decomposition of glucose by bee glucose-oxidase and certain Gluconobacter spp. This fact was confirmed by isotope analysis.


Assuntos
Dissacarídeos/química , Frutose/química , Gluconatos/química , Glucose/química , Mel/análise , Animais , Abelhas , Isótopos de Carbono/química , Cromatografia Líquida de Alta Pressão , Dissacarídeos/análise , Frutose/análise , Gluconatos/análise , Glucose/análise , Marcação por Isótopo , Espectrometria de Massas
15.
Chem Commun (Camb) ; 55(32): 4671-4674, 2019 Apr 16.
Artigo em Inglês | MEDLINE | ID: mdl-30938380

RESUMO

A metal-free oxygen reduction reaction (ORR) electrocatalyst with outstanding performance was obtained through an easy and one-pot synthesis of hemoglobin functionalized fructose@graphene-oxide (GO) nanocomposites. The active pyridinic nitrogen sites of the highly unfolded proteins together with the excellent electronic properties of GO appears to be the main factors causing the improved electrocatalytic activity.


Assuntos
Frutose/química , Grafite/química , Hemoglobinas/química , Nanocompostos/química , Óxidos/química , Oxigênio/química , Biocatálise , Técnicas Eletroquímicas/métodos , Oxirredução , Desdobramento de Proteína
16.
Molecules ; 24(5)2019 Mar 09.
Artigo em Inglês | MEDLINE | ID: mdl-30857298

RESUMO

Dry matter content (DMC) and reducing sugars (glucose, fructose) contents of three potato varieties for frying (Innovator, Lady Claire, and Markies) were determined by applying Fourier-transform near-infrared spectrometry (FT-NIR), with paying particular attention to tubers preparation (unpeeled, peeled, and transversally cut tubers) before spectral acquisitions. Potatoes were subjected to normal storage temperature as it is processed in the industry (8 °C) and lower temperature inducing sugar accumulations (5 °C) for 195 and 48 days, respectively. Prediction of DMC has been successfully modeled for all varieties. A common model to the three varieties reached R², root mean square error (RMSEP), and ratio performance to deviation (RPD) values of 0.84, 1.2, and 2.49. Prediction accuracy of reducing sugars was variety dependent. Reducing sugars were accurately predicted for Innovator (R² = 0.84, RMSEP = 0.097, and RPD = 2.86) and Markies (R² = 0.78, RMSEP = 0.033, and RPD = 2.15) and slightly less accurate for Lady Claire (R² = 0.63, RMSEP = 0.036, and RPD = 1.64). The lack of accuracy obtained with the Lady Claire variety is mainly due to the tight variability in sugar content measured over the storage. Finally, the best preparation of the tuber from the point of view of the accuracy of the prediction models was to use the whole peeled potato. Such preparation allowed for the improvement in RPD values by 15% to 38% the RPD values depending on reducing sugars and 35% for DMC.


Assuntos
Tubérculos/química , Espectroscopia de Luz Próxima ao Infravermelho/métodos , Frutose/química , Glucose/química , Análise dos Mínimos Quadrados
17.
Bioanalysis ; 11(5): 407-425, 2019 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-30887836

RESUMO

AIM: Fructose and sorbitol are utilized as biomarkers for nonalcoholic steatohepatitis. Measurement of fructose and sorbitol levels helps understanding disease progression, drug response and underlying mechanism. MATERIALS & METHODS: Stable isotope-labeled fructose and sorbitol were used as surrogate standards and internal standards. Human plasma samples were processed and analyzed by ultra performance LC®-MS/MS via chromatographic separation on a hydrophilic interaction liquid chromatography analytical column without derivatization. Assay was validated with biomarker fit-for-purpose concept. RESULTS: A 12-min ultra performance LC®-MS/MS method was developed and validated to directly measure fructose and sorbitol in human plasma with acceptable intra- and inter-assay precision and accuracy. CONCLUSION: This sensitive, selective, and high-throughput assay with suitable dynamic ranges was successfully applied to clinical studies to provide reliable fructose and sorbitol biomarker data.


Assuntos
Cromatografia Líquida/métodos , Frutose/química , Sorbitol/química , Espectrometria de Massas em Tandem/métodos , Método Duplo-Cego , Humanos , Interações Hidrofóbicas e Hidrofílicas , Reprodutibilidade dos Testes
18.
Nat Commun ; 10(1): 582, 2019 02 04.
Artigo em Inglês | MEDLINE | ID: mdl-30718496

RESUMO

In nature, self-assembly processes based on amphiphilic molecules play an integral part in the design of structures of higher order such as cells. Among them, amphiphilic glycoproteins or glycolipids take on a pivotal role due to their bioactivity. Here we show that sugars, in particular, fructose, are capable of directing the self-assembly of highly insoluble curcumin resulting in the formation of well-defined capsules based on non-covalent forces. Simply by mixing an aqueous solution of fructose and curcumin in an open vessel leads to the generation of capsules with sizes ranging between 100 and 150 nm independent of the initial concentrations used. Our results demonstrate that hydrogen bonding displayed by fructose can induce the self-assembly of hydrophobic molecules such as curcumin into well-ordered structures, and serving as a simple and virtually instantaneous way of making nanoparticles from curcumin in water with the potential for template polymerization and nanocarriers.


Assuntos
Curcumina/química , Nanopartículas/química , Açúcares/química , Portadores de Fármacos/química , Frutose/química , Ligação de Hidrogênio , Interações Hidrofóbicas e Hidrofílicas
19.
J Oleo Sci ; 68(3): 261-271, 2019 Mar 01.
Artigo em Inglês | MEDLINE | ID: mdl-30760673

RESUMO

A simple solid base catalyst, ammonium aluminum carbonate hydroxide (AACH), was prepared and its structure was characterized by many technologies, including XRD, FT-IR, SEM, BET and Elemental Analysis. The prepared catalyst was used to catalyze the conversion of glucose into 5-hydroxymethylfurfural (HMF) in ionic liquid 1-butyl-3-methylimidazolium chloride ([Bmim]+Cl-) and dimethyl sulfoxide (DMSO) mixtures. Various reaction conditions, including catalyst loading, reaction temperature, reaction duration and solvent, were investigated. A moderated HMF yield of 52.17 % was obtained at the mild reaction conditions (120°C for 4 h). More importantly, the catalyst could be reused for several times without the loss of its significant catalytic activities. After five reaction runs, a HMF yield about 49.34 % was also obtained.


Assuntos
Dimetil Sulfóxido/química , Furaldeído/análogos & derivados , Glucose/química , Imidazóis/química , Líquidos Iônicos/química , Carbonatos/química , Catálise , Frutose/química , Furaldeído/síntese química , Hidróxidos/química , Modelos Químicos , Solventes/química , Temperatura
20.
Food Chem ; 284: 236-244, 2019 Jun 30.
Artigo em Inglês | MEDLINE | ID: mdl-30744852

RESUMO

In light of a recent update in EU regulations governing levels of acrylamide in foodstuffs, further understanding of the role of different precursors is fundamental to extending mitigation strategies into a wider product range. Kinetic modelling was used to investigate the role of maltose in the formation of acrylamide during the finish-frying of french fries. The maltose concentration of raw white potato strips was systematically increased from 0 to 1.4% to observe the effect of this reducing disaccharide on acrylamide formation. A mathematical model, incorporating glucose, fructose and maltose and based on known Maillard reaction pathways, was developed which showed that acrylamide formation from maltose only contributed <10% to the total acrylamide. An additional kinetic model allowed for the formation of acrylamide directly from sugar-asparagine glycoconjugates. This model suggested that under these conditions, it is unlikely that acrylamide is formed directly from the maltose-asparagine conjugate.


Assuntos
Acrilamida/química , Culinária/métodos , Maltose/química , Solanum tuberosum/química , Acrilamida/análise , Asparagina , Frutose/química , Glucose/química , Cinética , Reação de Maillard , Modelos Químicos
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