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1.
J Environ Manage ; 364: 121473, 2024 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-38878582

RESUMO

The newly discovered ClO• and BrO• contribute to pollutant degradation in advanced oxidation processes, while acrylamide (AM) and acrylonitrile (ACN) are always the focus of scientists concerned due to their continuous production and highly toxic effects. Moreover, various particles with a graphene-like structure are the companions of AM/ACN in dry/wet sedimentation or aqueous phase existence, which play an important role in heterogeneous oxidation. Thus, this work focuses on the reaction mechanism and environmental effect of AM/ACN with ClO•/BrO•/HO• in the water environment under the influence of graphene (GP). The results show that although the reactivity sequence of AM and ACN takes the order of with HO• > with BrO• > with ClO•, the easiest channel always occurs at the same C-position of the two reactants. The reaction rate constants (k) of AM with three radicals are 2 times larger than that with ACN, and amide groups have a better ability to activate CC bonds than cyanide groups. The existence of GP can accelerate the target reaction, and the k increased by 9-13 orders of magnitude. The toxicity assessment results show that the toxic effect of most products is lower than that of parent compounds, but the environmental risk of products from ClO•/BrO•-adducts is higher than those from HO•-adducts. The oxidative degradation process based on ClO• and BrO• deserves special attention, and the catalytic effect of GP and its derivatives on the oxidation process is non-negligible.


Assuntos
Acrilamida , Acrilonitrila , Grafite , Oxirredução , Acrilonitrila/química , Acrilamida/química , Grafite/química , Poluentes Químicos da Água/química , Modelos Teóricos , Radical Hidroxila/química
2.
Sensors (Basel) ; 24(11)2024 May 29.
Artigo em Inglês | MEDLINE | ID: mdl-38894291

RESUMO

Acrylamide (AA), an odorless and colorless organic small-molecule compound found generally in thermally processed foods, possesses potential carcinogenic, neurotoxic, reproductive, and developmental toxicity. Compared with conventional methods for AA detection, bio/chemical sensors have attracted much interest in recent years owing to their reliability, sensitivity, selectivity, convenience, and low cost. This paper provides a comprehensive review of bio/chemical sensors utilized for the detection of AA over the past decade. Specifically, the content is concluded and systematically organized from the perspective of the sensing mechanism, state of selectivity, linear range, detection limits, and robustness. Subsequently, an analysis of the strengths and limitations of diverse analytical technologies ensues, contributing to a thorough discussion about the potential developments in point-of-care (POC) for AA detection in thermally processed foods at the conclusion of this review.


Assuntos
Acrilamida , Técnicas Biossensoriais , Sistemas Automatizados de Assistência Junto ao Leito , Acrilamida/análise , Acrilamida/química , Técnicas Biossensoriais/métodos , Humanos , Análise de Alimentos/métodos , Contaminação de Alimentos/análise
3.
Int J Biol Macromol ; 271(Pt 1): 132625, 2024 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-38795884

RESUMO

Graft copolymerization is an effective approach to improve performance of polysaccharide. However, selecting the most suitable modification strategy can be challenging due to the intricate molecular structure. Rational design through computer aided molecular dynamics (MD) simulations requires substantial computational resources. This study designed a simplified MD simulation strategy and suggested that grafting acrylamide (AM) could effectively adjust the molecular conformation of xanthan gum (XG) and its derivatives, thus regulating its viscosity and gelation properties. To rationally modify XG, a uniform experimental design was applied to tune the grafting ratios ranging from 72 % to 360 %, resulting in XG-AM solutions with viscosity ranging from 9 to 104 mPa•s at a concentration of 0.3 %. XG-AM was crosslinked by acid phenolic resin to generate gel with the viscosity of 7890 mPa·s in 3 days, which was 13 times the viscosity of unmodified XG. The controllable gelation will enhance the efficacy of XG-AM in oil recovery. By integrating rational selection of grafting strategies based on simplified MD simulation of polysaccharide derivatives and controllable grafting modification with specified grafting rates, customized production of polysaccharide derivatives can meet the requirements of a diverse range of applications.


Assuntos
Simulação de Dinâmica Molecular , Polissacarídeos Bacterianos , Polissacarídeos Bacterianos/química , Viscosidade , Acrilamida/química , Polimerização
4.
Colloids Surf B Biointerfaces ; 239: 113962, 2024 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-38749167

RESUMO

The undesirable and inevitable adhesion of marine organisms on submerged surfaces has seriously affect the environment, economy and society, so emerging and promising strategies for antifouling are required. Here, the novel and environmental strategy of the antibacterial and antialgal materials was proposed for the application of the antifouling coating without releasing harmful substances. The environment-friendly antifouling agent, the capsaicin derivative N-(2,5-dihydroxy-4-acrylamide meth-ylbenzyl)acrylamide (PHABA), was modified to the molecular chain of the polyurethane. The best tensile strength was up to 23.5 MPa of PUP-25% and the elongation at break was 415% of PUP-25%. The excellent wear resistance (300 wear cycles) and chemical solution resistance (H2SO4, NaOH, and NaCl solutions) revealed the applicability of the coating. PHABA would migrate to the surface of the polyurethane coating with time and enhanced the antibacterial and antialgal properties of the coating. PUP-25% prevented more than 90% of bacterial and algal adhesion, indicating the potential application of the antifouling coating.


Assuntos
Antibacterianos , Poliuretanos , Propriedades de Superfície , Poliuretanos/química , Poliuretanos/farmacologia , Antibacterianos/farmacologia , Antibacterianos/química , Hidroquinonas/química , Hidroquinonas/farmacologia , Testes de Sensibilidade Microbiana , Aderência Bacteriana/efeitos dos fármacos , Incrustação Biológica/prevenção & controle , Acrilamida/química , Acrilamida/farmacologia , Resistência à Tração
5.
J Comput Aided Mol Des ; 38(1): 21, 2024 May 01.
Artigo em Inglês | MEDLINE | ID: mdl-38693331

RESUMO

Covalent inhibition offers many advantages over non-covalent inhibition, but covalent warhead reactivity must be carefully balanced to maintain potency while avoiding unwanted side effects. While warhead reactivities are commonly measured with assays, a computational model to predict warhead reactivities could be useful for several aspects of the covalent inhibitor design process. Studies have shown correlations between covalent warhead reactivities and quantum mechanic (QM) properties that describe important aspects of the covalent reaction mechanism. However, the models from these studies are often linear regression equations and can have limitations associated with their usage. Applications of machine learning (ML) models to predict covalent warhead reactivities with QM descriptors are not extensively seen in the literature. This study uses QM descriptors, calculated at different levels of theory, to train ML models to predict reactivities of covalent acrylamide warheads. The QM/ML models are compared with linear regression models built upon the same QM descriptors and with ML models trained on structure-based features like Morgan fingerprints and RDKit descriptors. Experiments show that the QM/ML models outperform the linear regression models and the structure-based ML models, and literature test sets demonstrate the power of the QM/ML models to predict reactivities of unseen acrylamide warhead scaffolds. Ultimately, these QM/ML models are effective, computationally feasible tools that can expedite the design of new covalent inhibitors.


Assuntos
Cisteína , Desenho de Fármacos , Aprendizado de Máquina , Teoria Quântica , Cisteína/química , Acrilamida/química , Humanos , Modelos Moleculares , Relação Quantitativa Estrutura-Atividade , Modelos Lineares , Estrutura Molecular
6.
Food Chem ; 452: 139282, 2024 Sep 15.
Artigo em Inglês | MEDLINE | ID: mdl-38723562

RESUMO

Acrylamide (AA) is a neoformed compound in heated foods, mainly produced between asparagine (Asn) and glucose (Glc) during the Maillard reaction. Galacturonic acid (GalA), the major component of pectin, exhibits high activity in AA formation. This study investigated the pathway for AA formation between GalA and Asn. Three possible pathways were proposed: 1) The carbonyl group of GalA directly interacts with Asn to produce AA; 2) GalA undergoes an oxidative cleavage reaction to release α-dicarbonyl compounds, which subsequently leads to AA production; 3) 5-formyl-2-furancarboxylic acid, the thermal degradation product of GalA, reacts with Asn to generate AA. Structural analysis revealed that the COOH group in GalA accelerated intramolecular protonation and electron transfer processes, thereby increasing the formation of AA precursors such as decarboxylated Schiff base and α-dicarbonyl compounds, promoting AA formation. This study provides a theoretical basis and new insights into the formation and control of AA.


Assuntos
Acrilamida , Ácidos Hexurônicos , Acrilamida/química , Ácidos Hexurônicos/química , Reação de Maillard , Asparagina/química , Temperatura Alta , Pectinas/química , Estrutura Molecular
7.
Int J Biol Macromol ; 269(Pt 1): 132015, 2024 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-38697432

RESUMO

This study aimed to compare the effects of pectin and hydrolyzed pectin coating as pre-frying treatments on acrylamide content and quality characteristics of fried potato chips. The hydrolyzed pectin with molecular weight (Mw) of 8.81 ± 0.49 kDa was obtained through partial degradation of pectin (Mw: 747.57 ± 6.73 kDa) using pectinase. Results showed that both pectin and hydrolyzed pectin coating significantly inhibited acrylamide formation and inhibition rates exceeded 90 %. Hydrolyzed pectin had stronger inhibitory activity against acrylamide formation than pectin, especially when the concentration of hydrolyzed pectin was >2 %, its inhibitory rate exceeded 95 %. Compared to pectin coating, hydrolyzed pectin coating endow fried potato chips with smaller browning, higher crispness, less moisture but higher oil content. Overall, hydrolyzed pectin had better application prospects than pectin in inhibiting acrylamide formation of fried potato chips.


Assuntos
Acrilamida , Pectinas , Solanum tuberosum , Solanum tuberosum/química , Pectinas/química , Acrilamida/química , Hidrólise , Culinária , Peso Molecular
8.
Int J Mol Sci ; 25(9)2024 Apr 25.
Artigo em Inglês | MEDLINE | ID: mdl-38731875

RESUMO

Mass spectrometry has become the most prominent yet evolving technology in quantitative proteomics. Today, a number of label-free and label-based approaches are available for the relative and absolute quantification of proteins and peptides. However, the label-based methods rely solely on the employment of stable isotopes, which are expensive and often limited in availability. Here we propose a label-based quantification strategy, where the mass difference is identified by the differential alkylation of cysteines using iodoacetamide and acrylamide. The alkylation reactions were performed under identical experimental conditions; therefore, the method can be easily integrated into standard proteomic workflows. Using high-resolution mass spectrometry, the feasibility of this approach was assessed with a set of tryptic peptides of human serum albumin. Several critical questions, such as the efficiency of labeling and the effect of the differential alkylation on the peptide retention and fragmentation, were addressed. The concentration of the quality control samples calculated against the calibration curves were within the ±20% acceptance range. It was also demonstrated that heavy labeled peptides exhibit a similar extraction recovery and matrix effect to light ones. Consequently, the approach presented here may be a viable and cost-effective alternative of stable isotope labeling strategies for the quantification of cysteine-containing proteins.


Assuntos
Acrilamida , Cisteína , Iodoacetamida , Proteômica , Iodoacetamida/química , Alquilação , Cisteína/química , Cisteína/análise , Acrilamida/química , Acrilamida/análise , Humanos , Proteômica/métodos , Espectrometria de Massas/métodos , Marcação por Isótopo/métodos , Peptídeos/química , Peptídeos/análise , Espectrometria de Massas em Tandem/métodos
9.
J Agric Food Chem ; 72(20): 11360-11368, 2024 May 22.
Artigo em Inglês | MEDLINE | ID: mdl-38720533

RESUMO

In this study, a series of acrylamide derivatives containing trifluoromethylpyridine or piperazine fragments were rationally designed and synthesized. Subsequently, the in vitro antifungal activities of all of the synthesized compounds were evaluated. The findings revealed that compounds 6b, 6c, and 7e exhibited >80% antifungal activity against Phomopsis sp. (Ps) at the concentration of 50 µg/mL. Furthermore, the EC50 values for compounds 6b, 6c, and 7e against Ps were determined to be 4.49, 6.47, and 8.68 µg/mL, respectively, which were better than the positive control with azoxystrobin (24.83 µg/mL). At the concentration of 200 µg/mL, the protective activity of compound 6b against Ps reached 65%, which was comparable to that of azoxystrobin (60.9%). Comprehensive mechanistic studies, including morphological studies with fluorescence microscopy (FM), cytoplasmic leakage, and enzyme activity assays, indicated that compound 6b disrupts cell membrane integrity and induces the accumulation of defense enzyme activity, thereby inhibiting mycelial growth. Therefore, compound 6b serves as a valuable candidate for the development of novel fungicides for plant protection.


Assuntos
Acrilamida , Desenho de Fármacos , Fungicidas Industriais , Piridinas , Fungicidas Industriais/farmacologia , Fungicidas Industriais/síntese química , Fungicidas Industriais/química , Acrilamida/química , Piridinas/química , Piridinas/farmacologia , Piridinas/síntese química , Relação Estrutura-Atividade , Ascomicetos/efeitos dos fármacos , Ascomicetos/crescimento & desenvolvimento , Piperazina/química , Piperazina/farmacologia , Piperazinas/farmacologia , Piperazinas/química , Piperazinas/síntese química , Estrutura Molecular , Testes de Sensibilidade Microbiana , Doenças das Plantas/microbiologia
10.
Phytomedicine ; 128: 155589, 2024 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-38608487

RESUMO

BACKGROUND: Food products undergo a pronounced Maillard reaction (MR) during the cooking process, leading to the generation of substantial quantities of Maillard reaction products (MRPs). Within this category, advanced glycation end products (AGEs), acrylamide (AA), and heterocyclic amines (HAs) have been implicated as potential risk factors associated with the development of diseases. PURPOSE: To explore the effects of polyphenols, a class of bioactive compounds found in plants, on the inhibition of MRPs and related diseases. Previous research has mainly focused on their interactions with proteins and their effects on the gastrointestinal tract and other diseases, while fewer studies have examined their inhibitory effects on MRPs. The aim is to offer a scientific reference for future research investigating the inhibitory role of polyphenols in the MR. METHODS: The databases PubMed, Embase, Web of Science and The Cochrane Library were searched for appropriate research. RESULTS: Polyphenols have the potential to inhibit the formation of harmful MRPs and prevent related diseases. The inhibition of MRPs by polyphenols primarily occurs through the following mechanisms: trapping α-dicarbonyl compounds, scavenging free radicals, chelating metal ions, and preserving protein structure. Simultaneously, polyphenols exhibit the ability to impede the onset and progression of related diseases such as diabetes, atherosclerosis, cancer, and Alzheimer's disease through diverse pathways. CONCLUSION: This review presents that inhibition of polyphenols on Maillard reaction products and their induction of related diseases. Further research is imperative to enhance our comprehension of additional pathways affected by polyphenols and to fully uncover their potential application value in inhibiting MRPs.


Assuntos
Produtos Finais de Glicação Avançada , Reação de Maillard , Polifenóis , Polifenóis/farmacologia , Polifenóis/química , Produtos Finais de Glicação Avançada/antagonistas & inibidores , Humanos , Acrilamida/química , Doença de Alzheimer/tratamento farmacológico , Neoplasias/tratamento farmacológico , Aterosclerose/tratamento farmacológico , Aterosclerose/prevenção & controle , Animais
11.
Anal Methods ; 16(18): 2824-2839, 2024 May 09.
Artigo em Inglês | MEDLINE | ID: mdl-38669134

RESUMO

In this review, the mechanisms of acrylamide formation in food, along with aspects related to its toxicity and associated consumption risks, are investigated, highlighting the potential impact on human health. European regulations regarding acrylamide content in food products are also addressed, emphasizing the importance of monitoring and detecting this substance in nutrition, by public health protection measures. The primary objective of the research is to explore and analyze innovative methods for detecting acrylamide in food, with a particular focus on electrochemical biosensors. This research direction is motivated by the need to develop rapid, sensitive, and efficient monitoring techniques for this toxic compound in food products, considering the associated consumption risks. The research has revealed several significant results. Studies have shown that electrochemical biosensors based on hemoglobin exhibited increased sensitivity and low detection limits, capable of detecting very low concentrations of acrylamide in processed foods. Additionally, it has been found that the use of functionalized nanomaterials, such as carbon nanotubes and gold nanoparticles, has led to the improvement of electrochemical biosensor performance in acrylamide detection. The integration of these technological innovations and functionalization strategies has enhanced the sensitivity, specificity, and stability of biosensors in measuring acrylamides. Thus, the results of this research offer promising perspectives for the development of precise and efficient methods for monitoring acrylamides in food, contributing to the improvement of food quality control and the protection of consumer health.


Assuntos
Acrilamida , Técnicas Biossensoriais , Técnicas Eletroquímicas , Análise de Alimentos , Contaminação de Alimentos , Técnicas Biossensoriais/métodos , Acrilamida/análise , Acrilamida/química , Técnicas Eletroquímicas/métodos , Contaminação de Alimentos/análise , Análise de Alimentos/métodos , Humanos
12.
Int J Biol Macromol ; 268(Pt 1): 131652, 2024 May.
Artigo em Inglês | MEDLINE | ID: mdl-38649075

RESUMO

Vinylsulfonic acid (VSA), acrylamide (AM) and N, N methylene bis acrylamide(MBA) were copolymerized by radical polymerization in the presence of gum ghatti (GG) and treated water hyacianth (WH) in water. Several composite copolymers were prepared by varying the i) AM: VSA molar ratios ii) wt% of GG and iii) wt% of treated WH based on a Box-Behnken Design(BBD) of a response surface methodology (RSM) model with three input variables and the batch adsorption capacity (mg/g) of 100 mg/L Cd (II) from water as response. The composite polymer was characterized by Fourier transform Infrared spectroscopy (FTIR), X-ray diffraction (XRD), thermogravimetric analysis(TGA), X- ray photo electron spectroscopy (XPS), compressive strength, pH reversibility, pH at point zero charge (pHPZC), Brunauer-Emmett-Teller (BET) surface area and scanning electron microscopy (SEM). The network parameters of the composites were determined. The copolymer composite prepared with AM: VSA of 5:1 containing 10 wt% GG and 4 wt% treated WH showed an optimum batch adsorption capacity of 399.15 mg/g Cd (II) from water containing 100 mg/L Cd (II). The same composite showed an adsorption capacity of 170.1 mg/g and a removal% of 31.5 at a feed concentration/feed flow rate/bed height of 150 mgL-1/30mLmin-1/30 mm in a fixed bed column.


Assuntos
Celulose , Gomas Vegetais , Adsorção , Gomas Vegetais/química , Celulose/química , Celulose/análogos & derivados , Ácidos Sulfônicos/química , Purificação da Água/métodos , Água/química , Concentração de Íons de Hidrogênio , Acrilamida/química , Poluentes Químicos da Água/química , Poluentes Químicos da Água/isolamento & purificação , Polimerização , Difração de Raios X , Acrilamidas/química , Resinas Acrílicas/química , Espectroscopia de Infravermelho com Transformada de Fourier , Cádmio/química , Polivinil/química
13.
Food Addit Contam Part B Surveill ; 17(2): 122-128, 2024 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-38424740

RESUMO

This study was conducted to provide data on the amount of acrylamide (AA) in 270 heat-treated carbohydrate-rich foods in Turkey, determined by gas chromatography-mass spectrometry (GC-MS). A total of 270 samples were analysed and it was found that 85% of potato chips, 80% of biscuits, 85% of cakes, 80% of bread, 80% of roasted peanuts, 80% of roasted nuts and 85% of pretzels contained AA above the limit of quantification (LOQ). Analytical results indicated that 10 corn chips samples, 4 biscuits samples, all bread samples, all wheat bread samples, 2 dried bread samples and 1 pretzel sample contained AA levels above the benchmark levels of 150, 350, 50, 50, 300 and 300 µg/kg, respectively, as set by the European Commission.


Assuntos
Acrilamida , Contaminação de Alimentos , Cromatografia Gasosa-Espectrometria de Massas , Temperatura Alta , Acrilamida/análise , Acrilamida/química , Turquia , Contaminação de Alimentos/análise , Humanos , Culinária/métodos , Pão/análise , Limite de Detecção , Manipulação de Alimentos/métodos , Carboidratos da Dieta/análise , Solanum tuberosum/química
14.
J Mater Sci Mater Med ; 35(1): 20, 2024 Mar 25.
Artigo em Inglês | MEDLINE | ID: mdl-38526669

RESUMO

Xyloglucan is a rigid polysaccharide that belongs to the carbohydrate family. This hemicellulose compound has been widely used in biomedical research because of its pseudoplastic, mucoadhesive, mucomimetic, and biocompatibility properties. Xyloglucan is a polyose with no amino groups in its structure, which also limits its range of applications. It is still unknown whether grafting hydrophilic monomers onto xyloglucan can produce derivatives that overcome these shortcomings. This work aimed to prepare the first copolymers in which N-hydroxyethyl acrylamide is grafted onto tamarind xyloglucan by free-radical polymerization. The biocompatibility of these structures in vitro was evaluated using human dermal fibroblasts. Gamma radiation-induced graft polymerization was employed as an initiator by varying the radiation dose from 5-25 kGy. The structure of the graft copolymer, Xy-g-poly(N-hydroxyethyl acrylamide), was verified by thermal analysis, Fourier transform infrared spectroscopy, and nuclear magnetic resonance spectroscopy. The findings indicate that the degree of grafting and the cytotoxicity/viability of the xyloglucan-based copolymer were independent of dose. Notably, the grafted galactoxyloglucan exhibited efficient support for human dermal fibroblasts, showing heightened proliferative capacity and superior migration capabilities compared to the unmodified polymer. This copolymer might have the potential to be used in skin tissue engineering.


Assuntos
Acrilamida , Glucanos , Polímeros , Humanos , Acrilamida/química , Polimerização , Polímeros/química , Xilanos/química , Espectroscopia de Infravermelho com Transformada de Fourier
15.
World J Microbiol Biotechnol ; 40(3): 92, 2024 Feb 12.
Artigo em Inglês | MEDLINE | ID: mdl-38345704

RESUMO

A thermostable L-asparaginase was produced from Bacillus licheniformis UDS-5 (GenBank accession number, OP117154). The production conditions were optimized by the Plackett Burman method, followed by the Box Behnken method, where the enzyme production was enhanced up to fourfold. It secreted L-asparaginase optimally in the medium, pH 7, containing 0.5% (w/v) peptone, 1% (w/v) sodium chloride, 0.15% (w/v) beef extract, 0.15% (w/v) yeast extract, 3% (w/v) L-asparagine at 50 °C for 96 h. The enzyme, with a molecular weight of 85 kDa, was purified by ion exchange chromatography and size exclusion chromatography with better purification fold and percent yield. It displayed optimal catalysis at 70 °C in 20 mM Tris-Cl buffer, pH 8. The purified enzyme also exhibited significant salt tolerance too, making it a suitable candidate for the food application. The L-asparaginase was employed at different doses to evaluate its ability to mitigate acrylamide, while preparing French fries without any prior treatment. The salient attributes of B. licheniformis UDS-5 L-asparaginase, such as greater thermal stability, salt stability and acrylamide reduction in starchy foods, highlights its possible application in the food industry.


Assuntos
Acrilamida , Asparaginase , Asparaginase/química , Acrilamida/análise , Acrilamida/química , Asparagina , Indústria Alimentícia
16.
Bioorg Med Chem ; 100: 117627, 2024 Feb 15.
Artigo em Inglês | MEDLINE | ID: mdl-38310752

RESUMO

KRAS (Kirsten-RAS) is a highly mutated gene in the RAS (rat sarcoma) gene family that acts as a critical switch in intracellular signaling pathways, regulating cell proliferation, differentiation, and survival. The continuous activation of KRAS protein resulting from mutations leads to the activation of multiple downstream signaling pathways, inducing the development of malignant tumors. Despite the significant role of KRAS in tumorigenesis, targeted drugs against KRAS gene mutations have failed, and KRAS was once considered an undruggable target. The development of KRAS G12C mutant conformational modulators and the introduction of Sotorasib (R&D code: AMG510) have been a breakthrough in this field, with its remarkable clinical outcomes. Consequently, there is now a great number of KRAS G12C mutations. Patent applications for mutant GTPase KRAS G12C inhibitors, which are said to be covalently modified by cysteine codon 12, have been submitted since 2014. This review classifies KRAS G12C inhibitors based on their chemical structure and evaluates their biological properties. Additionally, it discusses the obstacles encountered in KRAS inhibitor research and the corresponding solutions.


Assuntos
Proteínas Proto-Oncogênicas p21(ras) , Transdução de Sinais , Humanos , Acrilamida/química , Carcinogênese , Diferenciação Celular , Mutação , Proteínas Proto-Oncogênicas p21(ras)/antagonistas & inibidores , Proteínas Proto-Oncogênicas p21(ras)/genética
17.
Int J Biol Macromol ; 260(Pt 2): 129546, 2024 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-38246461

RESUMO

Present investigation deals with the synthesis of psyllium based copolymeric hydrogels and evaluation of their physiochemical and biomedical properties. These copolymers have been prepared by grafting of poly(vinyl phosphonic acid) (poly (VPA)) and poly(acrylamide) (poly(AAm)) onto psyllium in the presence of crosslinker N,N-methylene bis acrylamide (NNMBA). These copolymers [psyllium-poly(VPA-co-AAm)-cl-NNMBA] were characterized by field emission-scanning electron micrographs (FE-SEM), electron dispersion X-ray analysis (EDAX), Atomic force microscopy (AFM), Fourier transform infrared spectroscopy (FTIR), 13C-nuclear magnetic resonance (NMR), X-ray diffraction (XRD), and thermogravimetric analysis (TGA)- differential thermal analysis (DTG). FESEM, AFM and XRD demonstrated heterogeneous morphology with a rough surface and an amorphous nature. Diffusion of ornidazole occurred with a non-Fickian diffusion mechanism, and the release profile data was fitted in the Korsemeyer-Peppas kinetic model. Biochemical analysis of hydrogel properties confirmed the blood-compatible nature during blood-polymer interactions and revealed haemolysis value 3.95 ± 0.05 %. The hydrogels exhibited mucoadhesive character during biomembrane-polymer interactions and demonstrated detachment force = 99.0 ± 0.016 mN. During 2,2-diphenyl-1-picrylhydrazyl reagent (DPPH) assay, free radical scavenging was observed 37.83 ± 3.64 % which illustrated antioxidant properties of hydrogels. Physiological and biomedical properties revealed that these hydrogels could be explored for drug delivery uses.


Assuntos
Acrilamida , Ácidos Fosforosos , Psyllium , Acrilamida/química , Psyllium/química , Hidrogéis/química , Acrilamidas/química , Polímeros/química , Espectroscopia de Infravermelho com Transformada de Fourier/métodos , Concentração de Íons de Hidrogênio
18.
J Sci Food Agric ; 104(7): 4070-4082, 2024 May.
Artigo em Inglês | MEDLINE | ID: mdl-38294231

RESUMO

BACKGROUND: In wheat-derived bakery products, the quantity of free asparagine (fAsn) has been identified as a key factor in acrylamide (AA) formation. Based on this assumption, four varieties of common wheat (Triticum aestivum L.), Stromboli, Montecarlo, Sothys and Cosmic, selected for their different fAsn content inside the grain, were studied to evaluate their potential in the production of pizza with reduced AA levels. To this purpose, wholemeal and refined flours were obtained from each variety. RESULTS: The fAsn content ranged from 0.25 to 3.30 mmol kg-1, with higher values for wholemeal flours which also showed greater amount of ash, fibre and damaged starch than refined wheat flours. All types of flours were separately used to produce wood oven baked pizza base, according to the Traditional Speciality Guaranteed EU Regulation (97/2010). AA reduction in the range 47-68% was found for all the selected wheat cultivars, compared with a commercial flour, with significantly lower values registered when refined flour was used. Moreover, refined leavened dough samples showed decreased levels of fAsn and reducing sugars due to the fermentation activity of yeasts. Furthermore, it was confirmed that pizza made with wholemeal flours exhibited lower rapidly digestible starch (RDS) and rapidly available glucose (RAG) values compared to that prepared with the refined flour. CONCLUSION: This study clearly shows that a reduced asparagine content in wheat flour is a key factor in the mitigation of AA formation in pizza base. Unfortunately, at the same time, it is highlighted how it is necessary to sacrifice the beneficial effects of fibre intake, such as lowering the glycaemic index, in order to reduce AA. © 2024 Society of Chemical Industry.


Assuntos
Asparagina , Farinha , Asparagina/química , Amido , Triticum/química , Acrilamida/química , Madeira , Pão
19.
Compr Rev Food Sci Food Saf ; 23(1): e13260, 2024 01.
Artigo em Inglês | MEDLINE | ID: mdl-38284574

RESUMO

Thermal processing techniques can lead to the formation of heat-induced toxic substances. Acrylamide is one contaminant that has received much scientific attention in recent years, and it is formed essentially during the Maillard reaction when foods rich in carbohydrates, particularly reducing sugars (glucose, fructose), and certain free amino acids, especially asparagine (ASN), are processed at high temperatures (>120°C). The highly variable free ASN concentration in raw materials makes it challenging for food businesses to keep acrylamide content below the European Commission benchmark levels, while avoiding flavor, color, and texture impacts on their products. Free ASN concentrations in crops are affected by environment, genotype, and soil fertilization, which can also influence protein content and amino acid composition. This review aims to provide an overview of free ASN and acrylamide quantification methods and mitigation strategies for acrylamide formation in foods, focusing on adding pulse flours to cereal-based snacks and bakery products. Overall, this review emphasizes the importance of these mitigation strategies in minimizing acrylamide formation in plant-based products and ensuring safer and healthier food options.


Assuntos
Asparagina , Grão Comestível , Asparagina/análise , Asparagina/química , Asparagina/metabolismo , Grão Comestível/química , Acrilamida/análise , Acrilamida/química , Acrilamida/toxicidade , Lanches , Carboidratos/análise , Carboidratos/química , Aminoácidos/análise
20.
Curr Microbiol ; 81(1): 30, 2023 Dec 05.
Artigo em Inglês | MEDLINE | ID: mdl-38052960

RESUMO

Acrylamide is the major by-product of the Maillard reactions in foods with the overheating processes of L-asparagine-rich foods with reducing sugars that usually allied with neurotoxicity and carcinogenicity. Several approaches have been used to prevent the formation of acrylamide, however, degrading the already formed acrylamide in foods remains unequivocal. Acrylamide hydrolyzing enzyme "amidohydrolase" is one of the most promising enzymes for acrylamide degradation in foods. So, amidohydrolase "amidase" from thermotolerant Aspergillus fumigatus EFBL was purified to their electrophoretic homogeneity by gel-filtration and ion-exchange chromatography, with overall purification folds 2.8 and yield 9.43%. The apparent molecular subunit structure of the purified A. fumigatus amidase was 50 kDa, with highest activity at reaction temperature of 40 °C and pH of 7.5 The enzyme displayed a significant thermal stability as revealed from the value of T1/2 (13.37 h), and thermal denaturation rate (Kr 0.832 × 10-3 min) at 50 °C, with metalloproteinic identity. The purified enzyme had a significant activity for acrylamide degradation in various food products such as meat, cookies, potato chips, and bread as revealed from the HPLC analysis and LC-MS analysis. So, with the purified amidase, the acrylamide in the food products was degraded by about 95% to acrylic acid, ensuring the possibility of using this enzyme in abolishing the toxic acrylamide in the foods products. This is the first report exploring the potency of A. fumigatus amidase for an actual degradation of acrylamide in foods efficiently. Further biochemical analyses are ongoing to assess the affinity of this enzyme for selective hydrolyses of acrylamide in foods, without affecting the beneficial stereochemical related compounds.


Assuntos
Acrilamida , Aspergillus fumigatus , Acrilamida/análise , Acrilamida/química , Amidoidrolases/química , Temperatura , Temperatura Alta
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