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1.
Actual. nutr ; 25(2): 96-102, abr.jun.2024. ilus
Artigo em Espanhol | LILACS | ID: biblio-1562046

RESUMO

Introducción: El hígado graso no alcohólico se enmarca en un grupo de patologías de etiología multifactorial, en el que la alimentación tendría un papel protagónico. En este sentido, el consumo de dietas ricas en fructosa, en especial a partir de fructosa añadida o jarabe de maíz alto en fructosa, ha sido motivo de investigación por su probable rol en la patogénesis de esta enfermedad. Metodología: Se realizó una búsqueda de artículos en relación con los efectos de las dietas ricas en fructosa sobre parámetros que podrían afectar la esteatosis hepática con el objetivo de organizar las principales evidencias al respecto. Resultados: Los estudios analizados tienden a evidenciar asociaciones positivas entre estas dietas y un mayor riesgo de desarrollar disbiosis intestinal, pérdida de integridad de la barrera intestinal y esteatosis hepática. Conclusiones: Los antecedentes recopilados en la presente revisión muestran evidencia de que este tipo de dietas favorecerían una serie de eventos que pueden conducir al hígado graso no alcohólico; por lo tanto, procurar un consumo adecuado de este monosacárido representaría una interesante alternativa de prevención para esta patología


Introduction: The non-alcoholic fatty liver disease falls within the group of multifactorial etiology pathologies in which food would play an important role. It is in this regard that the consumption of diets rich in fructose, especially from added fructose or corn syrup in fructose, has been a subject of investigation due to its likely roll in the pathogenesis of this disease. Methodology: A research for articles was performed about the effects of very rich fructose diets on parameters who could affect the liver steatosis in order to organize the main evidences. Results: The studies analized tend to report positive association between this diets and a higher risk of intestinal dysbiosis, intestinal barrier loss and partially with increased hepatic steatosis. Conclusions: The records compiled in the present review show evidence that this type of diets promote a serie of events that could result in non-alcoholic fatty liver disease so try a adequate consumption of this monosaccharides it would represent an interesting alternative to prevent this pathology


Assuntos
Xarope de Milho Rico em Frutose , Frutose , Disbiose , Hepatopatia Gordurosa não Alcoólica
2.
Med Sci Monit ; 30: e944050, 2024 Jul 07.
Artigo em Inglês | MEDLINE | ID: mdl-38971968

RESUMO

BACKGROUND Measurement of bite force plays a crucial role in assessment of the masticatory system. With a growing interest in detecting occlusal irregularities, bite force sensors have garnered attention in the biomedical field. This study aimed to introduce a hydrogel bite force sensor, based on hydroxyethyl-cellulose-fructose-water (HEC-F-water), for premolar and molar teeth, and to evaluate it using optical profilometry, infrared spectroscopy (FTIR), and Instron Tension testing system, with 2.5 cm (1 inch) margins at top, bottom, right, and left. MATERIAL AND METHODS We fabricated 20 HEC-F-water hydrogel samples sized with surface of 1×1 cm, with 2 different widths - 1 mm and 5 mm. The samples were characterized using optical profilometry and FTIR and their electrical characteristics were determined using an impedance analyzer. Aluminum (Al) electrodes, fabricated using Cutting Plotter, were used to form a HEC-F-water-based transducer, which was used for bite force sensing. The Instron tensile testing system was employed, utilizing 3D printed models of the upper and lower jaw, to simulate biting. Forces in the range between 40 N and 540 N were exerted upon the transducer, and the output change in the electrical signal was measured. RESULTS The study determined the transfer function between bite force and capacitance. The fabricated sensor exhibited a sensitivity of 3.98 pF/N, an input range of 500 N, output range of 2 nF, and accuracy of 95.9%. CONCLUSIONS This study introduces an edible bite force sensor employing an edible hydrogel as a dielectric, presenting a novel avenue in the development of edible sensorics in dentistry.


Assuntos
Força de Mordida , Humanos , Hidrogéis/química , Dente Molar , Frutose , Mastigação/fisiologia , Espectroscopia de Infravermelho com Transformada de Fourier/métodos , Celulose/química , Água , Dente Pré-Molar
3.
Commun Biol ; 7(1): 849, 2024 Jul 11.
Artigo em Inglês | MEDLINE | ID: mdl-38992061

RESUMO

Hereditary fructose intolerance (HFI) is a painful and potentially lethal genetic disease caused by a mutation in aldolase B resulting in accumulation of fructose-1-phosphate (F1P). No cure exists for HFI and treatment is limited to avoid exposure to fructose and sugar. Using aldolase B deficient mice, here we identify a yet unrecognized metabolic event activated in HFI and associated with the progression of the disease. Besides the accumulation of F1P, here we show that the activation of the purine degradation pathway is a common feature in aldolase B deficient mice exposed to fructose. The purine degradation pathway is a metabolic route initiated by adenosine monophosphate deaminase 2 (AMPD2) that regulates overall energy balance. We demonstrate that very low amounts of fructose are sufficient to activate AMPD2 in these mice via a phosphate trap. While blocking AMPD2 do not impact F1P accumulation and the risk of hypoglycemia, its deletion in hepatocytes markedly improves the metabolic dysregulation induced by fructose and corrects fat and glycogen storage while significantly increasing the voluntary tolerance of these mice to fructose. In summary, we provide evidence for a critical pathway activated in HFI that could be targeted to improve the metabolic consequences associated with fructose consumption.


Assuntos
AMP Desaminase , Intolerância à Frutose , Frutose-Bifosfato Aldolase , Frutose , Animais , Intolerância à Frutose/metabolismo , Intolerância à Frutose/genética , Camundongos , AMP Desaminase/genética , AMP Desaminase/metabolismo , Frutose-Bifosfato Aldolase/metabolismo , Frutose-Bifosfato Aldolase/genética , Frutose/metabolismo , Hepatopatias/metabolismo , Hepatopatias/etiologia , Hepatopatias/genética , Masculino , Camundongos Knockout , Camundongos Endogâmicos C57BL , Modelos Animais de Doenças , Fígado/metabolismo , Hepatócitos/metabolismo , Hepatócitos/efeitos dos fármacos , Metabolismo Energético/efeitos dos fármacos , Frutosefosfatos/metabolismo
4.
Int J Biol Sci ; 20(9): 3480-3496, 2024.
Artigo em Inglês | MEDLINE | ID: mdl-38993560

RESUMO

Metabolic dysfunction-associated steatotic liver disease (MASLD) is the most common cause of chronic liver-related morbidity and mortality. Though high fructose intake is acknowledged as a metabolic hazard, its role in the etiology of MASLD requires further clarification. Here, we demonstrated that high dietary fructose drives MASLD development and promotes MASLD progression in mice, and identified Usp2 as a fructose-responsive gene in the liver. Elevated USP2 levels were detected in the hepatocytes of MASLD mice; a similar increase was observed following fructose exposure in primary hepatocytes and mouse AML12 cells. Notably, hepatocytes overexpressing USP2 presented with exaggerated lipid accumulation and metabolic inflammation when exposed to fructose. Conversely, USP2 knockdown mitigated these fructose-induced changes. Furthermore, USP2 was found to activate the C/EBPα/11ß-HSD1 signaling, which further impacted the equilibrium of cortisol and cortisone in the circulation of mice. Collectively, our findings revealed the role of dietary fructose in MASLD pathogenesis and identified the USP2-mediated C/EBPα/ 11ß-HSD1 signaling as a potential target for the management of MASLD.


Assuntos
11-beta-Hidroxiesteroide Desidrogenase Tipo 1 , Frutose , Ubiquitina Tiolesterase , Animais , Camundongos , Frutose/efeitos adversos , Ubiquitina Tiolesterase/metabolismo , Ubiquitina Tiolesterase/genética , Masculino , 11-beta-Hidroxiesteroide Desidrogenase Tipo 1/metabolismo , 11-beta-Hidroxiesteroide Desidrogenase Tipo 1/genética , Camundongos Endogâmicos C57BL , Transdução de Sinais , Fígado Gorduroso/metabolismo , Hepatócitos/metabolismo , Fígado/metabolismo , Endopeptidases/metabolismo
5.
Sensors (Basel) ; 24(13)2024 Jun 29.
Artigo em Inglês | MEDLINE | ID: mdl-39001010

RESUMO

Carbohydrates are the main components of lentils, accounting for more than 60% of their composition. Their content is influenced by genetic factors, with different contents depending on the variety. These compounds have not only been linked to interesting health benefits, but they also have a significant influence on the techno-functional properties of lentil-derived products. In this study, the use of near-infrared spectroscopy (NIRS) to predict the concentration of total carbohydrate, fibre, starch, total sugars, fructose, sucrose and raffinose was investigated. For this purpose, six different cultivars of macrosperm (n = 37) and microsperm (n = 43) lentils have been analysed, the samples were recorded whole and ground and the suitability of both recording methods were compared. Different spectral and mathematical pre-treatments were evaluated before developing the calibration models using the Modified Partial Least Squares regression method, with a cross-validation and an external validation. The predictive models developed show excellent coefficients of determination (RSQ > 0.9) for the total sugars and fructose, sucrose, and raffinose. The recording of ground samples allowed for obtaining better models for the calibration of starch content (R > 0.8), total sugars and sucrose (R > 0.93), and raffinose (R > 0.91). The results obtained confirm that there is sufficient information in the NIRS spectral region for the development of predictive models for the quantification of the carbohydrate content in lentils.


Assuntos
Carboidratos , Lens (Planta) , Espectroscopia de Luz Próxima ao Infravermelho , Espectroscopia de Luz Próxima ao Infravermelho/métodos , Carboidratos/análise , Carboidratos/química , Lens (Planta)/química , Amido/análise , Amido/química , Sacarose/análise , Análise dos Mínimos Quadrados , Frutose/análise , Calibragem
6.
Arch Microbiol ; 206(8): 353, 2024 Jul 16.
Artigo em Inglês | MEDLINE | ID: mdl-39014223

RESUMO

Liamocins are molecules with a polyol lipid structure produced by rare strains of Aureobasidium pullulans. In recent years, liamocins have attracted attention due to their antibacterial, anticancer and surface-active properties, and promising potential applications have been identified in the food, agriculture, medical and pharmaceutical industries. This study is the first to investigate the effects of different carbon and nitrogen sources on the growth and liamocin production kinetics of A. pullulans NBRC 100716 strain. This strain was selected among six different A. pullulans strains whose liamocin productions were tested by us for the first time. In fermentations carried out in shaking water baths, the carbon source that most supported the liamocin production of this strain was fructose, and the nitrogen source was peptone-yeast extract combination. In the medium containing fructose and the peptone-yeast extract mixture, A. pullulans NBRC 100716 produced 4.26 g liamocin L-1. The specific liamocin production rate (qp) of the strain in this medium was 0.0090 g liamocin/g mo.h. This study is also the first to produce liamocin with a fructophilic A. pullulans strain. Present findings in this research also demonstrated the excellent biosurfactant capacity of the liamocin produced by this strain. The obtained liamocin reduced the water surface tension to a degree that can compete with synthetic surfactants. Furthermore, this is the first report to reveal that the fatty acid profile of liamocin obtained from A. pullulans NBRC 100716 contains an appreciable amount of unsaturated fatty acids and is similar to the composition of vegetable oil.


Assuntos
Aureobasidium , Carbono , Meios de Cultura , Fermentação , Nitrogênio , Nitrogênio/metabolismo , Carbono/metabolismo , Meios de Cultura/química , Aureobasidium/metabolismo , Cinética , Frutose/metabolismo
7.
S Afr Med J ; 114(6): e1748, 2024 May 31.
Artigo em Inglês | MEDLINE | ID: mdl-39041504

RESUMO

BACKGROUND: Non-alcoholic fatty liver disease (NAFLD) in South Africa and Africa at large is considered a hidden threat. Our local population is burdened with increased metabolic risk factors for NAFLD. Our setting requires a reasonable approach to screen for and aid the diagnosis of NAFLD. OBJECTIVES: To investigate serum fructosamine and random spot urine fructose levels as biomarkers for the screening, diagnosis and monitoring of NAFLD. The primary objective of this study was to compare serum fructosamine and random spot urine fructose levels between groups with different levels of NAFLD severity as measured by ultrasound. A secondary objective was to determine the association, if any, between serum transaminases, the aspartate aminotransferase (AST) to platelet ratio index (APRI) score, serum fructosamine and urine fructose in different groups with steatosis. METHODS: Using a cross-sectional study design, 65 patients with three different levels of NAFLD, as detected by imaging, were enrolled. The primary exposures measured were serum fructosamine with random spot urine fructose, and secondary exposures were the serum transaminases (AST and alanine aminotransferase (ALT)) and the APRI score. Patients identified at the departments of gastroenterology, general internal medicine and diagnostic radiology were invited to participate. RESULTS: There were 38, 17 and 10 patients with mild, moderate and severe steatosis, respectively. There was no significant difference between the groups regarding serum fructosamine, measured as median (interquartile range): mild 257 (241 - 286) µmol/L, moderate 239 (230 - 280) µmol/L and severe 260 (221 - 341) µmol/L, p=0.5; or random spot urine fructose: mild 0.86 (0.51 - 1.30) mmol/L, moderate 0.84 (0.51 - 2.62) mmol/L and severe 0.71 (0.58 - 1.09) mmol/L, p = 0.8. ALT (U/L) differed between groups: mild 19 (12 - 27), moderate 27 (22 - 33), severe 27 (21 - 56), p=0.03, but not AST (U/L) (p=0.7) nor APRI (p=0.9). Urine fructose and ALT were correlated in the moderate to severe steatosis group (R=0.490, p<0.05), but not in the mild steatosis group. Serum fructosamine was associated with age in the mild steatosis group but not the moderate-severe steatosis group (R=0.42, p<0.01). CONCLUSION: Serum fructosamine and random spot urine fructose did not vary with the severity of NAFLD, indicating that they would not be useful biomarkers in this condition.


Assuntos
Alanina Transaminase , Aspartato Aminotransferases , Biomarcadores , Frutosamina , Frutose , Hepatopatia Gordurosa não Alcoólica , Índice de Gravidade de Doença , Humanos , Frutosamina/sangue , Hepatopatia Gordurosa não Alcoólica/urina , Hepatopatia Gordurosa não Alcoólica/sangue , Estudos Transversais , Feminino , Frutose/urina , Masculino , Pessoa de Meia-Idade , Biomarcadores/sangue , Biomarcadores/urina , Adulto , Aspartato Aminotransferases/sangue , Alanina Transaminase/sangue , África do Sul/epidemiologia , Ultrassonografia
8.
Molecules ; 29(13)2024 Jun 21.
Artigo em Inglês | MEDLINE | ID: mdl-38998906

RESUMO

The effects of normal (NA) and controlled atmosphere (CA) storage and postharvest treatment with 1-methylcyclopropene (1-MCP) before CA storage for 5 months on the volatilome, biochemical composition and quality of 'Golden Delicious' (GD) and 'Red Delicious' (RD) apples were studied. Apples stored under NA and CA maintained and 1-MCP treatment increased firmness in both cultivars. NA storage resulted in a decrease of glucose, sucrose and fructose levels in both cultivars. When compared to CA storage, 1-MCP treatment caused a more significant decrease in sucrose levels and an increase in glucose levels. Additionally, 1-MCP-treated apples exhibited a significant decrease in malic acid content for both cultivars. All storage conditions led to significant changes in the abundance and composition of the volatilome in both cultivars. GD and RD apples responded differently to 1-MCP treatment compared to CA storage; higher abundance of hexanoate esters and (E,E)-α-farnesene was observed in RD apples treated with 1-MCP. While 1-MCP was effective in reducing (E,E)-α-farnesene abundance in GD apples, its impact on RD apples was more limited. However, for both cultivars, all storage conditions resulted in lower levels of 2-methylbutyl acetate, butyl acetate and hexyl acetate. The effectiveness of 1-MCP is cultivar dependent, with GD showing better results than RD.


Assuntos
Armazenamento de Alimentos , Malus , Malus/química , Malus/metabolismo , Ciclopropanos/farmacologia , Compostos Orgânicos Voláteis/análise , Compostos Orgânicos Voláteis/química , Frutas/química , Frutas/metabolismo , Sacarose/metabolismo , Malatos , Sesquiterpenos/análise , Glucose/metabolismo , Frutose/metabolismo , Frutose/análise
9.
Molecules ; 29(13)2024 Jun 27.
Artigo em Inglês | MEDLINE | ID: mdl-38999025

RESUMO

Enzymatic fructosylation has emerged as a strategy to enhance the hydrophilicity of polyphenols by introducing sugar moieties, leading to the development of phenolic glycosides, which exhibit improved solubility, stability, and biological activities compared to their non-glycosylated forms. This study provides a detailed analysis of the interactions between five phenolic fructosides (4MFPh, MFF, DFPh, MFPh, and MFPu) and twelve proteins (11ß-HS1, CRP, DPPIV, IRS, PPAR-γ, GK, AMPK, IR, GFAT, IL-1ß, IL-6, and TNF-α) associated with the pathogenesis of T2DM. The strongest interactions were observed for phlorizin fructosides (DFPh) with IR (-16.8 kcal/mol) and GFAT (-16.9 kcal/mol). MFPh with 11ß-HS1 (-13.99 kcal/mol) and GFAT (-12.55 kcal/mol). 4MFPh with GFAT (-11.79 kcal/mol) and IR (-12.11 kcal/mol). MFF with AMPK (-9.10 kcal/mol) and PPAR- γ (-9.71 kcal/mol), followed by puerarin and ferulic acid monofructosides. The fructoside group showed lower free energy binding values than the controls, metformin and sitagliptin. Hydrogen bonding (HB) was identified as the primary interaction mechanism, with specific polar amino acids such as serin, glutamine, glutamic acid, threonine, aspartic acid, and lysine identified as key contributors. ADMET results indicated favorable absorption and distribution characteristics of the fructosides. These findings provide valuable information for further exploration of phenolic fructosides as potential therapeutic agents for T2DM.


Assuntos
Hipoglicemiantes , Hipoglicemiantes/química , Hipoglicemiantes/farmacologia , Fenóis/química , Fenóis/farmacologia , Humanos , Simulação de Acoplamento Molecular , Isoflavonas/química , Isoflavonas/metabolismo , Isoflavonas/farmacologia , Diabetes Mellitus Tipo 2/tratamento farmacológico , Diabetes Mellitus Tipo 2/metabolismo , Florizina/química , Florizina/farmacologia , Frutose/química , Frutose/metabolismo , Glicosilação , Ácidos Cumáricos/química , Ácidos Cumáricos/metabolismo
10.
Nutrients ; 16(13)2024 Jun 29.
Artigo em Inglês | MEDLINE | ID: mdl-38999831

RESUMO

The interactions of different dietary doses of copper with fructose contribute to the development of metabolic dysfunction-associated steatotic liver disease (MASLD) via the gut-liver axis. The underlying mechanisms remain elusive. The aim of this study was to identify the specific pathways leading to gut barrier dysfunction in the ileum using a proteomics approach in a rat model. Male weanling Sprague Dawley rats were fed diets with adequate copper (CuA), marginal copper (CuM), or supplemented copper (CuS) in the absence or presence of fructose supplementation (CuAF, CuMF, and CuSF) for 4 weeks. Ileum protein was extracted and analyzed with an LC-MS. A total of 2847 differentially expressed proteins (DEPs) were identified and submitted to functional enrichment analysis. As a result, the ileum proteome and signaling pathways that were differentially altered were revealed. Of note, the CuAF is characterized by the enrichment of oxidative phosphorylation and ribosome as analyzed with the KEGG; the CuMF is characterized by an enriched arachidonic acid metabolism pathway; and focal adhesion, the regulation of the actin cytoskeleton, and tight junction were significantly enriched by the CuSF. In conclusion, our proteomics analysis identified the specific pathways in the ileum related to the different dietary doses of copper-fructose interactions, suggesting that distinct mechanisms in the gut are involved in the development of MASLD.


Assuntos
Cobre , Frutose , Íleo , Fígado , Proteômica , Ratos Sprague-Dawley , Animais , Frutose/administração & dosagem , Frutose/efeitos adversos , Masculino , Cobre/metabolismo , Proteômica/métodos , Íleo/metabolismo , Íleo/efeitos dos fármacos , Fígado/metabolismo , Fígado/efeitos dos fármacos , Ratos , Dieta , Proteoma/metabolismo , Transdução de Sinais/efeitos dos fármacos , Hepatopatia Gordurosa não Alcoólica/metabolismo , Hepatopatia Gordurosa não Alcoólica/etiologia , Suplementos Nutricionais
11.
Int J Mol Sci ; 25(13)2024 Jun 25.
Artigo em Inglês | MEDLINE | ID: mdl-39000037

RESUMO

A complication of reducing sugars is that they can undergo Maillard chemical reactions, forming advanced glycation end-products (AGEs) that can induce oxidative stress and inflammation via engagements with the main receptor for AGEs (RAGE) in various tissues. Certain sugars, such as glucose and fructose, are well known to cause AGE formation. Recently, allulose has emerged as a rare natural sugar that is an epimer of fructose and which is of low caloric content that is minimally metabolized, leading to it being introduced as a low-calorie sugar alternative. However, the relative ability of allulose to generate AGEs compared to glucose and fructose is not known. Here we assess the accumulation of AGEs in cell-free, in vitro, and in vivo conditions in response to allulose and compare it to glycation mediated by glucose or fructose. AGEs were quantified in cell-free samples, cell culture media and lysates, and rat serum with glycation-specific ELISAs. In cell-free conditions, we observed concentration and time-dependent increases in AGEs when bovine serum albumin (BSA) was incubated with glucose or fructose and significantly less glycation when incubated with allulose. AGEs were significantly elevated when pulmonary alveolar type II-like cells were co-incubated with glucose or fructose; however, significantly less AGEs were detected when cells were exposed to allulose. AGE quantification in serum obtained from rats fed a high-fat, low-carb (HFLC) Western diet for 2 weeks revealed significantly less glycation in animals co-administered allulose compared to those exposed to stevia. These results suggest allulose is associated with less AGE formation compared to fructose or glucose, and support its safety as a low-calorie sugar alternative.


Assuntos
Frutose , Produtos Finais de Glicação Avançada , Animais , Produtos Finais de Glicação Avançada/metabolismo , Ratos , Glicosilação , Frutose/metabolismo , Monossacarídeos/metabolismo , Glucose/metabolismo , Masculino , Soroalbumina Bovina/metabolismo , Receptor para Produtos Finais de Glicação Avançada/metabolismo , Ratos Sprague-Dawley
12.
Bioresour Technol ; 406: 131071, 2024 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-38971391

RESUMO

The isomerization of glucose is a crucial step for biomass valorization to downstream chemicals. Herein, highly dispersed MgO doped biochar (BM-0.5@450) was prepared from rice straw via a solvent-free ball milling pretreatment and pyrolysis under nitrogen conditions. The nano-MgO doped biochar demonstrated enhanced conversion of glucose in water at low temperatures. A 31 % yield of fructose was obtained from glucose over BM-0.5@450 at 50 °C with 80.0 % selectivity. At 60 °C for 140 min, BM-0.5@450 achieved a 32.5 % yield of fructose. Compared to catalyst synthesized from conventional impregnation method (IM@450), the BM-0.5@450 catalyst shows much higher fructose yields (32.5 % vs 25.9 %), which can be attributed to smaller crystallite size of MgO (11.32 nm vs 19.58 nm) and homogenous distribution. The mechanism study shows that the activated MgOH+·OH- group by water facilitated the deprotonation process leading to the formation of key intermediate enediol.


Assuntos
Carvão Vegetal , Glucose , Óxido de Magnésio , Carvão Vegetal/química , Óxido de Magnésio/química , Glucose/química , Isomerismo , Catálise , Oryza/química , Frutose/química , Temperatura Baixa , Temperatura
14.
J Agric Food Chem ; 72(26): 14821-14829, 2024 Jul 03.
Artigo em Inglês | MEDLINE | ID: mdl-38897918

RESUMO

d-Allulose, a C-3 epimer of d-fructose, has great market potential in food, healthcare, and medicine due to its excellent biochemical and physiological properties. Microbial fermentation for d-allulose production is being developed, which contributes to cost savings and environmental protection. A novel metabolic pathway for the biosynthesis of d-allulose from a d-xylose-methanol mixture has shown potential for industrial application. In this study, an artificial antisense RNA (asRNA) was introduced into engineered Escherichia coli to diminish the flow of pentose phosphate (PP) pathway, while the UDP-glucose-4-epimerase (GalE) was knocked out to prevent the synthesis of byproducts. As a result, the d-allulose yield on d-xylose was increased by 35.1%. Then, we designed a d-xylose-sensitive translation control system to regulate the expression of the formaldehyde detoxification operon (FrmRAB), achieving self-inductive detoxification by cells. Finally, fed-batch fermentation was carried out to improve the productivity of the cell factory. The d-allulose titer reached 98.6 mM, with a yield of 0.615 mM/mM on d-xylose and a productivity of 0.969 mM/h.


Assuntos
Escherichia coli , Fermentação , Metanol , RNA Antissenso , Xilose , Escherichia coli/genética , Escherichia coli/metabolismo , Xilose/metabolismo , RNA Antissenso/genética , RNA Antissenso/metabolismo , Metanol/metabolismo , Engenharia Metabólica , Frutose/metabolismo , Proteínas de Escherichia coli/genética , Proteínas de Escherichia coli/metabolismo
16.
Biochem Biophys Res Commun ; 725: 150271, 2024 Sep 17.
Artigo em Inglês | MEDLINE | ID: mdl-38901222

RESUMO

The R-type voltage-gated calcium channel CaV2.3 is predominantly located in the presynapse and is implicated in distinct types of epileptic seizures. It has consequently emerged as a molecular target in seizure treatment. Here, we determined the cryo-EM structure of the CaV2.3-α2δ1-ß1 complex in the topiramate-bound state at a 3.0 Å resolution. We provide a snapshot of the binding site of topiramate, a widely prescribed antiepileptic drug, on a voltage-gated ion channel. The binding site is located at an intracellular juxtamembrane hydrophilic cavity. Further structural analysis revealed that topiramate may allosterically facilitate channel inactivation. These findings provide fundamental insights into the mechanism underlying the inhibitory effect of topiramate on CaV and NaV channels, elucidating a previously unseen modulator binding site and thus pointing toward a route for the development of new drugs.


Assuntos
Anticonvulsivantes , Canais de Cálcio Tipo R , Microscopia Crioeletrônica , Topiramato , Anticonvulsivantes/química , Anticonvulsivantes/farmacologia , Topiramato/química , Topiramato/farmacologia , Humanos , Regulação Alostérica/efeitos dos fármacos , Canais de Cálcio Tipo R/química , Canais de Cálcio Tipo R/metabolismo , Sítios de Ligação , Modelos Moleculares , Células HEK293 , Conformação Proteica , Frutose/química , Frutose/análogos & derivados , Frutose/metabolismo , Animais , Proteínas de Transporte de Cátions
17.
Int J Biol Macromol ; 273(Pt 1): 132803, 2024 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-38848836

RESUMO

Bionanocomposites offer a promising solution to the plastic waste crisis. Although tapioca starch shows potential as a bioplastic material, it is characterized by low mechanical properties, poor thermal stability, and high water absorption owing to its hydrophilic nature. To increase the flexibility of the material and reduce the transmission rate of oxygen and water vapor, additives such as fructose and titanium dioxide (TiO2) can be incorporated into the material. TiO2 nanoparticles are commonly utilized in agriculture to enhance nutrient release and promote plant growth. In this study, X-ray diffraction analysis revealed that TiO2 reduced crystal size while increasing the crystallinity of bionanocomposites. Fourier-transform infrared spectroscopy analysis revealed an absorption peak at 3397 cm-1, indicating hydrogen bonding between TiO2 and starch-OH groups, and a peak at 773 cm-1, indicating an increase in the intensity of Ti-O-Ti stretching vibrations with the incorporation of TiO2. Water absorption rate results confirmed that TiO2 addition enhanced bionanocomposite resistance to water vapor and moisture, evidenced by increased tensile strength from 0.11 to 0.49 MPa and Young's modulus from 2.48 to 5.26 MPa, as well as decreased elongation at break from 21.46 % to 2.36 % in bionanocomposites with TiO2. Furthermore, with TiO2 addition, the biodegradation rate of the bionanocomposites decreased, which is beneficial for enhancing plant nutrient content.


Assuntos
Embalagem de Alimentos , Frutose , Manihot , Nanocompostos , Amido , Titânio , Nanocompostos/química , Titânio/química , Amido/química , Embalagem de Alimentos/métodos , Frutose/química , Manihot/química , Fertilizantes , Resistência à Tração , Água/química , Difração de Raios X , Espectroscopia de Infravermelho com Transformada de Fourier
18.
Spectrochim Acta A Mol Biomol Spectrosc ; 320: 124612, 2024 Nov 05.
Artigo em Inglês | MEDLINE | ID: mdl-38857548

RESUMO

High fructose intake is an important cause of metabolic disease. Due to the increasing prevalence of metabolic diseases worldwide, the development of an accurate and efficient tool for monitoring fructose in food is urgently needed to control the intake of fructose. Herein, a new fluorescent probe NBD-PQ-B with 7-nitrobenz-2-oxa-1, 3-diazole (NBD) as the fluorophore, piperazine (PQ) as the bridging group and phenylboronic acid (B) as the recognition receptor, was synthesized to detect fructose. The fluorescence of NBD-PQ-B increased linearly at 550 nm at an excitation wavelength of 497 nm with increasing fructose concentration from 0.1 to 20 mM. The limit of detection (LOD) of fructose was 40 µM. The pKa values of NBD-PQ-B and its fructose complexes were 4.1 and 10.0, respectively. In addition, NBD-PQ-B bound to fructose in a few seconds. The present technique was applied to determine the fructose content in beverages, honey, and watermelon with satisfactory results. Finally, the system could not only be applied in an aqueous solution with a spectrophotometer, but also be fabricated as a NBD-PQ-B/polyvinyl oxide (PEO) film by electrospinning for on-site food analysis simply with the assistance of a smartphone.


Assuntos
Corantes Fluorescentes , Análise de Alimentos , Frutose , Espectrometria de Fluorescência , Frutose/análise , Corantes Fluorescentes/química , Espectrometria de Fluorescência/métodos , Análise de Alimentos/métodos , Limite de Detecção , Mel/análise , Bebidas/análise , 4-Cloro-7-nitrobenzofurazano/química
19.
Int J Biol Macromol ; 273(Pt 1): 133027, 2024 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-38857717

RESUMO

D-allulose, a low-calorie rare sugar catalyzed by D-allulose 3-epimerase (DAE), is highly sought after for its potential health benefits. However, poor reusability and stability of DAE limited its popularization in industrial applications. Although metal-organic frameworks (MOFs) offer a promising enzyme platform for enzyme immobilization, developing customized strategies for MOF immobilization of enzymes remains challenging. In this study, we introduce a designable strategy involving the construction of bimetal-organic frameworks (ZnCo-MOF) based on metal ions compatibility. The DAE@MOFs materials were prepared and characterized, and the immobilization of DAE and the enzymatic characteristics of the MOF-immobilized DAE were subsequently evaluated. Remarkably, DAE@ZnCo-MOF exhibited superior recyclability which could maintain 95 % relative activity after 8 consecutive cycles. The storage stability is significantly improved compared to the free form, with a relative activity of 116 % remaining after 30 days. Molecular docking was also employed to investigate the interaction between DAE and the components of MOFs synthesis. The results demonstrate that the DAE@ZnCo-MOF exhibited enhanced catalytic efficiency and increased stability. This study introduces a viable and adaptable MOF-based immobilization strategy for enzymes, which holds the potential to expand the implementation of enzyme biocatalysts in a multitude of disciplines.


Assuntos
Enzimas Imobilizadas , Estruturas Metalorgânicas , Simulação de Acoplamento Molecular , Estruturas Metalorgânicas/química , Enzimas Imobilizadas/química , Enzimas Imobilizadas/metabolismo , Carboidratos Epimerases/química , Carboidratos Epimerases/metabolismo , Estabilidade Enzimática , Íons/química , Frutose
20.
Nutrients ; 16(12)2024 Jun 10.
Artigo em Inglês | MEDLINE | ID: mdl-38931176

RESUMO

The global rise in type 2 diabetes (T2D) and obesity necessitates innovative dietary interventions. This study investigates the effects of allulose, a rare sugar shown to reduce blood glucose, in a rat model of diet-induced obesity and T2D. Over 12 weeks, we hypothesized that allulose supplementation would improve body weight, insulin sensitivity, and glycemic control. Our results showed that allulose mitigated the adverse effects of high-fat, high-sugar diets, including reduced body weight gain and improved insulin resistance. The allulose group exhibited lower food consumption and increased levels of glucagon-like peptide-1 (GLP-1), enhancing glucose regulation and appetite control. Additionally, allulose prevented liver triglyceride accumulation and promoted mitochondrial uncoupling in adipose tissue. These findings suggest that allulose supplementation can improve metabolic health markers, making it a promising dietary component for managing obesity and T2D. Further research is needed to explore the long-term benefits and mechanisms of allulose in metabolic disease prevention and management. This study supports the potential of allulose as a safe and effective intervention for improving metabolic health in the context of dietary excess.


Assuntos
Glicemia , Diabetes Mellitus Tipo 2 , Dieta Hiperlipídica , Frutose , Resistência à Insulina , Obesidade , Animais , Frutose/administração & dosagem , Masculino , Obesidade/metabolismo , Diabetes Mellitus Tipo 2/prevenção & controle , Diabetes Mellitus Tipo 2/metabolismo , Glicemia/metabolismo , Ratos , Dieta Hiperlipídica/efeitos adversos , Fígado/metabolismo , Peptídeo 1 Semelhante ao Glucagon/metabolismo , Peptídeo 1 Semelhante ao Glucagon/sangue , Triglicerídeos/sangue , Ratos Sprague-Dawley , Tecido Adiposo/metabolismo , Aumento de Peso , Modelos Animais de Doenças
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