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1.
Molecules ; 27(20)2022 Oct 13.
Artículo en Inglés | MEDLINE | ID: mdl-36296459

RESUMEN

Deficiency of folates can cause various health problems, and germination is a potential way to enrich folates in grain-based food materials. In the present study, the effects of six amino acids (phenylalanine, tyrosine, tryptophan, glutamate, γ-aminobutyric acid, and p-aminobenzoic acid) on folate accumulation during wheat germination under red light radiation were investigated, and an optimized combination of amino acids for promoting folate enrichment was established. The results showed that applying phenylalanine, tyrosine, tryptophan, glutamate, or p-aminobenzoic acid to wheat seedlings during germination can significantly increase the content of total folates through activating the synthesis of the precursors for folate synthesis (pterin and p-aminobenzoic acid) or condensation of these two moieties. Meanwhile, up-regulation of corresponding genes was observed by measuring their expressions to investigate the mechanism for promoting the accumulation of folates. The highest content of folates (ca. 417 µg/100 g DW) was observed when the germinated wheat was cultured with a mixture of 1.5 mM phenylalanine, 0.5 mM tyrosine, 0.5 mM tryptophan, 0.75 mM p-aminobenzoic acid, and 0.5 mM glutamic acid, which was 50% higher than the control seedlings. This study established a promising and practical approach to enhance the accumulation of folates in wheat seedlings.


Asunto(s)
Germinación , Plantones , Plantones/metabolismo , Triticum/química , Aminoácidos/metabolismo , Ácido 4-Aminobenzoico , Triptófano/metabolismo , Ácido Fólico/metabolismo , Grano Comestible/metabolismo , Ácido gamma-Aminobutírico/metabolismo , Tirosina/metabolismo , Fenilalanina/metabolismo , Glutamatos/metabolismo
2.
Clin Lab ; 67(9)2021 Sep 01.
Artículo en Inglés | MEDLINE | ID: mdl-34542985

RESUMEN

BACKGROUND: The current study aims to investigate the differences of glycoprotein non-metastatic melanoma protein B (GPNMB) levels between gestational diabetes mellitus (GDM) women and normal blood glucose women during pregnancy to provide the basis for early intervention and treatment of GDM. METHODS: The level of GPNMB was detected using an enzyme-linked immunosorbent assay (ELISA). Pearson's correlation assay was performed to analyze the correlation between serum GPNMB and fasting plasma glucose (FPG) or hemoglobin A1c (HbA1c). The receiver operating characteristic (ROC) curve was carried out to analyze the diagnostic value of serum GPNMB. RESULTS: Our data showed that the serum GPNMB level in GDM group was higher than that in normal blood glucose group at 5 - 12 weeks, 13 - 23 weeks, and 24 - 28 weeks of gestation, but there was no significant difference at 29 - 37 weeks of gestation. Meanwhile, the total level of serum GPNMB in GDM group was significantly higher than that in normal blood glucose group. Further study indicated that serum GPNMB positively correlated with FPG (r = 0.562, p < 0.0001) or HbA1c (r = 0.652, p < 0.0001). ROC analysis showed that serum GPNMB level at 13 - 23 weeks of gestation had a good predictive effect on predicting GDM at 24 weeks of gestation and beyond. When the cutoff value of serum GPNMB level was 2.46 µg/L, the sensitivity and specificity were 80% and 72%, respectively. CONCLUSIONS: The serum GPNMB level at 13 - 23 weeks of gestation is an independent risk factor for GDM in 24 weeks and beyond, and early inhibition with GPNMB may provide a preventive measure in GDM women.


Asunto(s)
Diabetes Gestacional , Melanoma , Glucemia , Diabetes Gestacional/diagnóstico , Femenino , Hemoglobina Glucada/análisis , Humanos , Melanoma/diagnóstico , Glicoproteínas de Membrana , Embarazo , Receptores Fc
3.
Org Biomol Chem ; 17(33): 7694-7705, 2019 09 07.
Artículo en Inglés | MEDLINE | ID: mdl-31328213

RESUMEN

Membranous organelles are major endogenous sources of reactive oxygen and nitrogen species. When present at high levels, these species can cause macromolecular damage and disease. To better detect and scavenge free radical forms of the reactive species at their sources, we investigated whether nitrone spin traps could be selectively targeted to intracellular membranes using a bioorthogonal imaging approach. Electron paramagnetic resonance imaging demonstrated that the novel cyclic nitrone 5-dodecylcarbamoyl-5-N-dodecylacetamide-1-pyroline-N-oxide (diC12PO) could be used to target the nitrone moiety to liposomes composed of phosphatidyl choline. To test localization with authentic membranes in living cells, fluorophores were introduced via strain-promoted alkyne-nitrone cycloaddition (SPANC). Two fluorophore-conjugated alkynes were investigated: hexynamide-fluoresceine (HYA-FL) and dibenzylcyclooctyne-PEG4-5/6-sulforhodamine B (DBCO-Rhod). Computational and mass spectrometry experiments confirmed the cycloadduct formation of DBCO-Rhod (but not HYA-FL) with diC12PO in cell-free solution. Confocal microscopy of bovine aortic endothelial cells treated sequentially with diC12PO and DBCO-Rhod demonstrated clear localization of fluorescence with intracellular membranes. These results indicate that targeting of nitrone spin traps to cellular membranes is feasible, and that a bioorthogonal approach can aid the interrogation of their intracellular compartmentalization properties.


Asunto(s)
Acetamidas/química , Teoría Funcional de la Densidad , Fluorescencia , Imagen Óptica , Acetamidas/síntesis química , Animales , Bovinos , Células Cultivadas , Espectroscopía de Resonancia por Spin del Electrón , Estructura Molecular
4.
Eur Spine J ; 26(4): 985-997, 2017 04.
Artículo en Inglés | MEDLINE | ID: mdl-27314663

RESUMEN

BACKGROUND: Anterior cervical discectomy and fusion (ACDF) has been considered as a gold standard for symptomatic cervical disc degeneration (CDD), which may result in progressive degeneration of the adjacent segments. The artificial cervical disc was designed to reduce the number of lesions in the adjacent segments. Clinical studies have demonstrated equivalence of cervical disc arthroplasty (CDA) for anterior cervical discectomy and fusion in single segment cervical disc degeneration. But for two contiguous levels cervical disc degeneration (CDD), which kind of treatment method is better is controversial. PURPOSE: To evaluate the clinical effects requiring surgical intervention between anterior cervical discectomy and fusion (ACDF) and cervical disc arthroplasty (CDA) at two contiguous levels cervical disc degeneration. METHODS: We conducted a comprehensive search in multiple databases, including PubMed, Cochrane Central Register of Controlled Trials, EBSCO and EMBASE. We identified that six reports meet inclusion criteria. Two independent reviewers performed the data extraction from archives. Data analysis was conducted with RevMan 5.3. RESULTS: After applying inclusion and exclusion criteria, six papers were included in meta-analyses. The overall sample size at baseline was 650 patients (317 in the TDR group and 333 in the ACDF group). The results of the meta-analysis indicated that the CDA patients had significant superiorities in mean blood loss (P < 0.00001, standard mean differences (SMD) = -0.85, 95 % confidence interval (CI) = -1.22 to -0.48); reoperation (P = 0.0009, risk ratio (RR) = 0.28, 95 % confidence interval (CI) = 0.13-0.59), adjacent segment degeneration (P < 0.00001, risk ratio (RR) = 0.48, 95 % confidence interval (CI) = 0.40-0.58) and Neck Disability Index (P = 0.002, SMD = 0.31, 95 % CI = 0.12-0.50). No significant difference was identified between the two groups regarding mean surgical time (P = 0.84, SMD = -0.04, 95 % CI = -0.40 to 0.32), neck and arm pain scores (P = 0.52, SMD = 0.06, 95 % CI = -0.13 to 0.25) reported on a visual analog scale and rate of postoperative complications [risk ratio (RR) = 0.79; 95 % CI = 0.50-1.25; P = 0.31]. The CDA group of sagittal range of motion (ROM) of the operated and adjacent levels, functional segment units (FSU) and C2-7 is superior to ACDF group by radiographic data of peroperation, postoperation and follow-up. CONCLUSION: We can learn from this meta-analysis that the cervical disc arthroplasty (CDA) group is equivalent and in some aspects has more significant clinical outcomes than the ACDF group at two contiguous levels CDD.


Asunto(s)
Artroplastia/métodos , Vértebras Cervicales/cirugía , Discectomía/métodos , Degeneración del Disco Intervertebral/cirugía , Fusión Vertebral/métodos , Humanos , Dolor de Cuello , Tempo Operativo , Dimensión del Dolor , Complicaciones Posoperatorias/epidemiología , Ensayos Clínicos Controlados Aleatorios como Asunto , Rango del Movimiento Articular , Reoperación , Resultado del Tratamiento
5.
J Biochem Mol Toxicol ; 30(5): 258-64, 2016 May.
Artículo en Inglés | MEDLINE | ID: mdl-26749074

RESUMEN

The interaction of hydroxyethyl starch 130/0.4 (Voluven) with human serum albumin (HSA) has been investigated by fluorescence (steady state and synchronous), Fourier transforms infrared (FT-IR), and circular dichroism (CD) spectroscopies. Analysis of the fluorescence quenching data of HSA by Voluven using the Stern-Volmer method revealed the formation of 1:1 ground-state complex. Evaluation of binding parameters and binding energy indicated that the binding reaction was exothermic. On the basis of fluorescence measurements, it was concluded that electrostatic forces play a crucial role in stabilizing the complex. The binding distance was calculated by using Förster resonance energy transfer (FRET) theory. The conformational changes of HSA were obtained qualitatively as well as quantitatively using synchronous fluorescence, FT-IR, and CD. The HSA underwent partial unfolding in the presence of Voluven.


Asunto(s)
Derivados de Hidroxietil Almidón/química , Albúmina Sérica/química , Sitios de Unión , Dicroismo Circular , Humanos , Modelos Moleculares , Unión Proteica , Dominios Proteicos , Estructura Secundaria de Proteína , Espectrometría de Fluorescencia , Espectroscopía Infrarroja por Transformada de Fourier , Electricidad Estática , Termodinámica
6.
J Food Sci Technol ; 53(10): 3685-3694, 2016 Oct.
Artículo en Inglés | MEDLINE | ID: mdl-28017983

RESUMEN

In the study, osmotically dehydrated cherry tomatoes were partially dried to water activity between 0.746 and 0.868, vacuum-packed and stored at 4-30 °C for 60 days. Adaptive neuro-fuzzy inference system (ANFIS) was utilized to predict the physicochemical and microbiological parameters of these partially dried cherry tomatoes during storage. Satisfactory accuracies were obtained when ANFIS was used to predict the lycopene and total phenolic contents, color and microbial contamination. The coefficients of determination for all the ANFIS models were higher than 0.86 and showed better performance for prediction compared with models developed by response surface methodology. Through ANFIS modeling, the effects of storage conditions on the properties of partially dried cherry tomatoes were visualized. Generally, contents of lycopene and total phenolics decreased with the increase in water activity, temperature and storage time, while aerobic plate count and number of yeasts and molds increased at high water activities and temperatures. Overall, ANFIS approach can be used as an effective tool to study the quality decrease and microbial pollution of partially dried cherry tomatoes during storage, as well as identify the suitable preservation conditions.

7.
J Sci Food Agric ; 94(8): 1585-91, 2014 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-24170570

RESUMEN

BACKGROUND: γ-Aminobutyric acid (GABA) is synthesized via the polyamine degradation pathway in plants, with diamine oxidase (DAO) being the key enzyme. In this study the cDNA of DAO in fava bean was cloned and its expression in seeds germinating under hypoxia-NaCl stress was investigated. RESULTS: Fava bean DAO cDNA is 2199 bp long and contains 2025 bp of open reading frame that encodes 675 amino acid peptides with a calculated molecular weight of 76.31 kDa and a pI of 5.41. Hypoxia and hypoxia-NaCl stress enhanced DAO activity and resulted in GABA accumulation in germinating fava bean. However, DAO gene expression was down-regulated under hypoxia compared with non-stress condition, while its expression in the cotyledon and shoot was up-regulated under hypoxia-NaCl. In addition, DAO expression could be promoted to enhance GABA accumulation after increasing the stress intensity using NaCl. DAO gene expression was significantly inhibited by aminoguanidine treatment under hypoxia but increased under hypoxia-NaCl. CONCLUSION: Under hypoxia, GABA accumulation due to NaCl was mainly concentrated in the cotyledon. The GABA content increase under hypoxia did not result from DAO gene expression, but DAO existing in seeds was activated under hypoxia. DAO gene expression was up-regulated to enhance GABA accumulation after increasing the stress intensity.


Asunto(s)
Amina Oxidasa (conteniendo Cobre)/genética , Regulación de la Expresión Génica de las Plantas , Semillas/enzimología , Vicia faba/enzimología , Ácido gamma-Aminobutírico/biosíntesis , Amina Oxidasa (conteniendo Cobre)/metabolismo , Clonación Molecular , ADN de Plantas/química , ADN de Plantas/genética , Regulación de la Expresión Génica de las Plantas/efectos de los fármacos , Germinación , Guanidinas/farmacología , Oxígeno/administración & dosificación , Semillas/efectos de los fármacos , Semillas/crecimiento & desarrollo , Análisis de Secuencia de ADN , Cloruro de Sodio/administración & dosificación , Vicia faba/genética , Vicia faba/metabolismo
8.
Arch Med Sci ; 20(1): 302-308, 2024.
Artículo en Inglés | MEDLINE | ID: mdl-38414449

RESUMEN

Introduction: Osteoarthritis (OA) is a common inflammatory joint disease characterised by progressive cartilage destruction. Management of this condition remains a significant challenge, and new therapies are required. We investigated the protective effects of miR-106a mimics in a murine model of OA. Material and methods: This study was performed using both in vitro and in vivo OA models. Primary chondrocytes were isolated from female rats, with inflammation induced via treatment with lipopolysaccharide (LPS). Then the effects of a miR-106a mimic were examined based on the level of inflammatory cytokine production and apoptotic signalling following LPS stimulation. An in vivo rat model of OA was generated by injecting LPS into the anterior cruciate ligament, followed by treatment with miR-106a mimics. Then, inflammatory and apoptotic protein expression was assessed in the cartilage tissue. Results: Treatment with miR-106a mimic reduced the levels of inflammatory cytokines and apoptotic proteins in cartilage tissues following LPS-induced inflammation. Furthermore, the mimic ameliorated the expression of DR-6 mRNA and DR6, IκBα, and p65 proteins in chondrocytes. Similar effects were seen in the in vivo model, with the mimic attenuating expression of NF-κB, p65, IκBα, and DR6 proteins and improving histopathological outcomes in the chondrocytes of OA rats. Conclusions: Treatment with miR-106a mimic ameliorates inflammation in cartilage tissues of OA subjects by activating death receptor 6 via the NF-κB signalling pathway.

9.
Chemistry ; 19(24): 7931-6, 2013 Jun 10.
Artículo en Inglés | MEDLINE | ID: mdl-23589382

RESUMEN

A small amphiphile that contains a coumarin unit and alkynyl groups, as a two-photon-cleavable segment and polymerizable groups, respectively, was designed and synthesized. The amphiphile showed a critical aggregation concentration of about 4.6×10(-5) M and formed a vesicle-type assembly. The formed vesicles were stabilized by in situ "click" polymerization without altering their morphology. Hydrophobic and hydrophilic guests can be encapsulated within the vesicle membrane and inside the aqueous core of the vesicle, respectively. The loaded guests can be released from the vesicle by using UV or near-IR stimuli, through splitting up the amphiphilic structure of the amphiphile. Distinguished dose-controlled photorelease of the polymeric vesicle is achieved with the maintenance of vesicular integrity, which makes the guest release dependent on the amount of cleavage of the amphiphilic structure during irradiation. This study provides a potential strategy for the development of versatile and stable drug-delivery systems that offer sustained and photo-triggered release.


Asunto(s)
Alquinos/síntesis química , Cumarinas/síntesis química , Sistemas de Liberación de Medicamentos , Fotones , Polímeros/síntesis química , Tensoactivos/síntesis química , Alquinos/química , Cumarinas/química , Interacciones Hidrofóbicas e Hidrofílicas , Micelas , Estructura Molecular , Procesos Fotoquímicos , Polimerizacion , Polímeros/administración & dosificación , Polímeros/química , Tensoactivos/administración & dosificación , Tensoactivos/química
10.
Carbohydr Polym ; 319: 121137, 2023 Nov 01.
Artículo en Inglés | MEDLINE | ID: mdl-37567727

RESUMEN

This study aimed to enhance the synthesis of carboxymethyl starch (CMS) by induced electric field (IEF). Corn starch was alkalized, pumped into IEF system, and then reacted with monochloroacetic acid at excitation voltages of 0-400 V. IEF enhanced the carboxymethylation by accelerating the rate of OH- and ClCH2COO- attacking starch particles and slightly intensifying the thermal effect by ~7.1 °C (30 min). Compared with the control (0 V), IEF increased the degree of substitution and reaction efficiency by 0.056-0.148 and 9.37-24.56 %, caused more destruction in starch granular and crystal structure, and thus increased its water solubility, swelling power, and paste transparency. Furthermore, some new crystals were formed during IEF treatment, which enhanced the thermostability of CMS, showing an increase of the maximum decomposition temperature by 16-26 °C. Overall, the results classified that IEF could improve the carboxymethylation and enhance the thermostability of products, which provided guides for the applications of electro-techniques in starch modification involving charged species.

11.
Food Chem ; 404(Pt B): 134709, 2023 Mar 15.
Artículo en Inglés | MEDLINE | ID: mdl-36323041

RESUMEN

This study aimed to improve γ-aminobutyric acid (GABA) content and sensory characteristics of brown rice (BR) cake by static magnetic field (SMF)-assisted germination. BR was pre-treated by SMF (10 mT, 60 min, 25 °C), germinated for 36 h, and then germinated BR (GBR) was used to prepare rice cake. The optimal formula was: 60 % GBR, 40 % white rice, 1 % yeast, 20 % sugar, and 55 % water. SMF significantly increased the GABA content by stimulating glutamate decarboxylase, with the values increasing from 28.17 to 32.43 mg/100 g and from 2.50 to 6.27 mg/100 g in GBR (36 h) and GBR cake, respectively. SMF also altered the swelling power and water solubility of GBR flour by promoting the hydrolysis of starch, protein, and fiber, thus improving the texture, flavor, and storage stability of GBR cake. Overall, SMF could be a prospective technique for improving the nutritional and sensory qualities of whole-grain food.


Asunto(s)
Oryza , Oryza/metabolismo , Estudios Prospectivos , Ácido gamma-Aminobutírico/metabolismo , Agua/metabolismo , Campos Magnéticos , Germinación
12.
Ultrason Sonochem ; 101: 106692, 2023 Dec.
Artículo en Inglés | MEDLINE | ID: mdl-37988955

RESUMEN

The effects of hydrodynamic cavitation (HC) and ultrasound cavitation (UC) on the lipoxygenase activity and physicochemical properties of soy milk were evaluated. The results revealed that both ultrasound cavitation and hydrodynamic cavitation significantly inactivated the lipoxygenase activity. After the exposure to ultrasound cavitation at 522.5 W/L and 70 °C for 12 min, the lipoxygenase activity was inactivated by 96.47 %. Meanwhile, HC treatment with the cavitation number of 0.0133 for 240 min led to the loss of 79.31 % of lipoxygenase activity. An artificial neural network was used to model and visualize the effects of different parameters after ultrasound cavitation treatment on the inactivation efficiency of soy milk. Turbiscan test results showed that hydrodynamic and ultrasound cavitation decreased the instability index and particle size of soy milk. Moreover, the total free amino acid content was significantly increased after hydrodynamic and ultrasound cavitation treatment. Gas chromatography-mass spectrometry showed that the total content of beany flavor compounds decreased after acoustic cavitation and HC treatment. Acoustic cavitation and HC affected the tertiary and secondary structure of soy milk, which was related to the inactivation of lipoxygenase. We aim to explore a potential and effective way of the application in soy milk processing by comparing the ultrasound equipped with heat treatment and hydrodymic cavitation.


Asunto(s)
Leche de Soja , Leche de Soja/química , Hidrodinámica , Lipooxigenasa/metabolismo , Fenómenos Químicos , Tamaño de la Partícula
13.
Food Chem ; 405(Pt B): 134982, 2023 Mar 30.
Artículo en Inglés | MEDLINE | ID: mdl-36435102

RESUMEN

Three strains, including L. fermentum, L. plantarum and S. thermophilus, were combined to ferment blueberry juice. Through the sequential simplex lattice mixture design, regression modeling and genetic algorithm optimization, it was found that the combination of S. thermophilus with either L. fermentum or L. plantarum weakened the capacity of Lactobacillus strains to enrich phenolics, and the combinations of these strains had no synergistic effect of synthesizing lactic acid. The resulting optimal inoculation proportion to enrich phenolics was the mixed L. fermentum and L. plantarum at 0.5:0.5. After fermentation for 48 h, total phenolic, ferulic acid, rutin, and quercetin-3-rhamnoside of mixed fermented samples were 82.19 %, 15.22 %, 79.08 % and 98.59 % higher than the unfermented juice, and their contents were all highest among the fermented samples. Moreover, the samples fermented by mixed strains possessed higher amounts of 3-methyl-1-butanol, 2-methyl-1-propanol, 2-heptanone and 2-pentanone than samples fermented by L. fermentum, S. thermophilus and unfermented samples.


Asunto(s)
Arándanos Azules (Planta) , Probióticos , Fermentación , Fenoles , Aprendizaje Automático
14.
Food Res Int ; 174(Pt 2): 113663, 2023 Dec.
Artículo en Inglés | MEDLINE | ID: mdl-37981365

RESUMEN

This study aimed to investigate the effect of static magnetic field (SMF, 0-10 mT) on the quality of rice dumplings subjected to 7, 14, 21, and 28 freeze-thaw cycles. The underlying mechanism was explored by monitoring changes in water phase transition, water distribution, and structural and physicochemical properties of rice flour. Results suggested that SMF enables the formation of small ice crystals by accelerating freezing rate, shortening phase transition time, and increasing bound water content, which attributes to reducing the mechanical damage on starch granules and thus improves the quality of frozen rice dumpling. After 7-28 freeze-thaw cycles, SMF treatment increased the whiteness by 0.08-1.58, reduced the cracking ratio by 1.67 %-8.34 %, decreased the water loss ratio by 0-0.75 %, and significantly improved the texture of cooked rice dumplings. This study confirmed the feasibility of SMF in improving the quality of rice dumpling, which contributes to expanding the applications of magnetic freezer in the preservation of starch-based foods.


Asunto(s)
Oryza , Congelación , Oryza/química , Harina , Agua/química , Almidón/química
15.
Langmuir ; 28(3): 1733-7, 2012 Jan 24.
Artículo en Inglés | MEDLINE | ID: mdl-22172224

RESUMEN

A small amphiphile consisting of hydrophilic tetraethylene glycol monoacrylate and hydrophobic alkyl chain which were connected by an o-nitrobenzyl unit, a photolabile group, was designed and synthesized. The critical aggregate concentration of the synthesized amphiphile was determined to be about 3 × 10(-5) M by the fluorescence probe technique. Nanosized vesicles were prepared and stabilized by in-situ radical polymerization without altering the morphology. The polymeric vesicle was highly stable which retained vesicular shape under dilution or UV irradiation. Hydrophobic guests can be encapsulated within the vesicle membrane and released out of the vesicle by UV stimulus through splitting the amphiphilic structure of the amphiphile. Distinguished dose-controlled photorelease of the polymeric vesicle is achieved due to the maintenance of the vesicular shape integrity which makes the guest release depend on the cleavage amount of amphiphilic structure during UV irradiation. This study provides a promising strategy to develop stable drug delivery systems for sustained and phototriggered release.


Asunto(s)
Preparaciones de Acción Retardada/química , Sistemas de Liberación de Medicamentos , Acrilatos/química , Preparaciones de Acción Retardada/síntesis química , Diseño de Fármacos , Colorantes Fluorescentes/química , Interacciones Hidrofóbicas e Hidrofílicas , Microscopía Electrónica de Rastreo , Microscopía Electrónica de Transmisión , Nanotecnología/métodos , Oxazinas/química , Fotoquímica/métodos , Dispersión de Radiación , Rayos Ultravioleta
16.
J Sci Food Agric ; 92(8): 1709-15, 2012 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-22228559

RESUMEN

BACKGROUND: γ-Aminobutyric acid (GABA) is a non-protein amino acid with bioactive functions for human health. Diamine oxidase (DAO, EC 1.4.3.6) is one of the key enzymes for GABA formation. In the present study, this enzyme was purified from 5 day germinated fava bean and its properties were investigated in vitro. RESULTS: The molecular mass of the enzyme estimated by Sephadex G-100 gel filtration was 121 kDa. Sodium dodecyl sulfate polyacrylamide gel electrophoresis (SDS-PAGE) displayed a single band at a molecular mass of 52 kDa. The enzyme had optimal activity at 40 °C and retained its activity after being incubated at 30 °C for 30 min. It showed higher activity at pH 6.5 than at other pH values. The enzyme was significantly inhibited by Mg(2+), Cu(2+), Fe(3+), aminoguanidine, ethylene glycol tetraacetic acid (EGTA), ethylene diamine tetraacetic acid disodium salt (EDTA-Na(2)), L-cysteine and ß-mercaptoethanol. The K(m) value of DAO was 0.23 mmol L(-1) for putrescine and 0.96 mmol L(-1) for spermidine. However, the enzyme did not degrade spermine. CONCLUSION: DAO from germinated fava bean was purified. The optimal reaction temperature and pH of the enzyme were mild. The enzyme had higher affinity to putrescine than to spermidine and spermine.


Asunto(s)
Amina Oxidasa (conteniendo Cobre)/metabolismo , Germinación/fisiología , Semillas/enzimología , Vicia faba/enzimología , Ácido gamma-Aminobutírico/biosíntesis , Amina Oxidasa (conteniendo Cobre)/química , Amina Oxidasa (conteniendo Cobre)/aislamiento & purificación , Electroforesis en Gel de Poliacrilamida , Inhibidores Enzimáticos/farmacología , Humanos , Concentración de Iones de Hidrógeno , Peso Molecular , Putrescina/metabolismo , Espermidina/metabolismo , Especificidad por Sustrato , Temperatura
17.
Carbohydr Polym ; 292: 119654, 2022 Sep 15.
Artículo en Inglés | MEDLINE | ID: mdl-35725161

RESUMEN

This study aimed to improve the effect of moderate electric field (MEF) treatment on the structural and physicochemical properties of maize starch by adding 1-butyl-3-methylimidazolium chloride ([bmim]Cl). Starch (20%, w/v) was mixed with [bmim]Cl solution (0, 30%, 50%, and 70%, w/w), and then electro-treated (5 V/cm, 50 Hz) at 60 °C for 10 min. As the [bmim]Cl concentration increased, the electro-induced disintegration of starch granules was enhanced due to the intensified Joule heat and decreased pH of reaction bulk. After electro-treated in 70% w/w [bmim]Cl, a transparent solution of starch was observed and the recovered starch tended to dissolve rather than swell in water. Compared with water-bath heating, MEF caused more destruction in the granular and crystal structure, increased the particle size, decreased the pasting viscosity, and reduced the gelatinization enthalpy and thermostability of starch. The obtained results could provide guidance for the application of electro-based techniques in starch modification.


Asunto(s)
Almidón , Zea mays , Imidazoles/química , Almidón/química , Viscosidad , Agua , Zea mays/química
18.
Food Chem ; 383: 132392, 2022 Jul 30.
Artículo en Inglés | MEDLINE | ID: mdl-35176715

RESUMEN

The study aimed to explore the stimulating effect of static magnetic field (SMF) treatment on germinated brown rice (GBR) by monitoring changes in α-amylase activity and structural and functional properties of starch. Brown rice was exposed to SMF (10 mT, 60 min, 25 °C) and then germinated for 0 h -72 h at 30 °C. Compared with the control, SMF treatment improved α-amylase activity (15.2%), leading to the hydrolysis of starch into reducing sugar (8.2%) and increasing the germination rate (9.7% -158.8%), shoot length (9.1% -87.3%), root length (19.2% -110.0%), and fresh weight (0.9% -16.5%). In view of the properties of starch, SMF treatment also altered the surface microstructure, induced partial losses of birefringence, exerted no significant effect on the crystalline type, slightly increased the gelatinization temperatures, and significantly decreased the peak viscosity. This study suggested that SMF could serve as a prospective technique for GBR products processing.


Asunto(s)
Oryza , Almidón , Harina , Germinación , Campos Magnéticos , Oryza/química , Estudios Prospectivos , Almidón/química , alfa-Amilasas
19.
Ultrason Sonochem ; 84: 105977, 2022 Mar.
Artículo en Inglés | MEDLINE | ID: mdl-35279633

RESUMEN

In this investigation, the combinations of exogenous pretreatment (melatonin or vitamin C) and contact ultrasound-assisted air drying were utilized to dry broccoli florets. To understand the influences of the studied dehydration methods on the conversion of glucoraphanin to bioactive sulforaphane in broccoli, various components (like glucoraphanin, sulforaphane, myrosinase, etc.) and factors (temperature and moisture) involved in the metabolism pathway were analyzed. The results showed that compared with direct air drying, the sequential exogenous pretreatment and contact ultrasound drying shortened the drying time by 19.0-22.7%. Meanwhile, contact sonication could promote the degradation of glucoraphanin. Both melatonin pretreatment and vitamin C pretreatment showed protective effects on the sulforaphane content and myrosinase activity during the subsequent drying process. At the end of drying, the sulforaphane content in samples dehydrated by the sequential melatonin (or vitamin C) pretreatment and ultrasound-intensified drying was 14.4% (or 26.5%) higher than only air-dried samples. The correlation analysis revealed that the exogenous pretreatment or ultrasound could affect the enzymatic degradation of glucoraphanin and the generation of sulforaphane through weakening the connections of sulforaphane-myrosinase, sulforaphane-VC, and VC-myrosinase. Overall, the reported results can enrich the biochemistry knowledge about the transformation of glucoraphanin to sulforaphane in cruciferous vegetables during drying, and the combined VC/melatonin pretreatment and ultrasound drying is conducive to protect bioactive sulforaphane in dehydrated broccoli.


Asunto(s)
Brassica , Brassica/química , Glucosinolatos/química , Imidoésteres , Redes y Vías Metabólicas , Oximas/metabolismo , Sulfóxidos/metabolismo
20.
Int J Biol Macromol ; 200: 370-377, 2022 Mar 01.
Artículo en Inglés | MEDLINE | ID: mdl-34999042

RESUMEN

This study aimed to explore the effect of induced electric field (IEF) treatment on acid hydrolysis of corn starch by altering the connection modes of sample coils of a 4-reactor IEF system. Results suggested that IEF treatment could enhance the hydrolysis of corn starch and series connection (1. RRRR, η=16ESi2Pin4ZSi+Zload) exhibited higher energy efficiency than parallel (9. (RRRR), η=4ESi2PinZSi+4Zload), thus contributing to more extensive hydrolysis. Although no new functional group was formed, the starch granules were partially cracked into pieces and the crystallinity was slightly increased after IEF-assisted hydrolysis. Differential scanning calorimetry results indicated that IEF-assisted hydrolysis increased the gelatinization temperatures but decreased the enthalpy of starch, with a greatest variation was observed by series connection. Rapid visco-analysis showed that IEF-assisted hydrolysis greatly decreased the pasting viscosity of corn starch and also series connection showed the strongest reduction. The obtained results could provide a theoretical guide for the applications of IEF technology in biomaterial processing.


Asunto(s)
Almidón
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