Your browser doesn't support javascript.
loading
Mostrar: 20 | 50 | 100
Resultados 1 - 20 de 6.061
Filtrar
1.
J Chromatogr A ; 1733: 465241, 2024 Sep 27.
Artigo em Inglês | MEDLINE | ID: mdl-39153428

RESUMO

Cigars, treasured for their rich aromatic profiles, occupy a notable segment in the global consumer market. The objective of this study was to characterize the volatile aroma compounds that shape the flavor profiles of six distinct varieties of Great Wall cigars, contributing to the understanding of cigar aroma analysis. Utilizing HS-GC-IMS and sensory evaluation, the study discerned the aroma profiles of GJ No. 6 (GJ), Animal from the Chinese zodiac (SX), Range Rover No. 3 Classic (JD), Miracle 132 (QJ), Sheng Shi No. 5 (SS), and Red 132 (HS) cigars. The analysis uncovered a spectrum of characteristic aromas, including tobacco, creaminess, cocoa, leather, baking, herbaceous, leathery, woodsy, and fruity notes. A total of 88 compounds were identified, categorized into 11 chemical classes, with their quantities varying among the cigars in a descending order of QJ, JD, GJ, SS, HS, and SX. 24 compounds, such as 2-heptanone, n-butanol, 2,6-dimethylpyrazine and 2-furfuryl methyl sulfide were considered as key differential components. The volatile components were effectively differentiated using principal component analysis (PCA), orthogonal partial least squares-discriminant analysis (OPLS-DA), and cluster analysis, revealing correlations between sensory attributes, key components, and electronic nose (E-nose). This research introduces a novel method for analyzing volatile aroma components in cigars, offering insights to enhance cigar quality and to foster the development of new products with unique aroma profiles.


Assuntos
Técnicas de Química Analítica , Nariz Eletrônico , Cromatografia Gasosa-Espectrometria de Massas , Odorantes , Produtos do Tabaco , Odorantes/análise , Produtos do Tabaco/análise , Técnicas de Química Analítica/métodos , Compostos Orgânicos Voláteis/análise
2.
J Pharm Biomed Anal ; 249: 116344, 2024 Oct 15.
Artigo em Inglês | MEDLINE | ID: mdl-39053096

RESUMO

The performance of analytical test methods is critical to ensure decisions that affect efficacy and quality of pharmaceutical products are based on accurate and reliable results. As described in USP <1220> and advocated for in ICH Q14, continued verification of critical method attributes linked to bias and precision is essential to ensure method performance throughout the lifecycle of an analytical test method. As continued verification programs for analytical methods within the pharmaceutical industry mature, additional monitoring tools are required to deliver robust and cost-effective verification programs. Herein, a novel methodology is presented to evaluated analytical method variability directly from results generated during routine method execution. The implementation of the methodology is demonstrated for a small molecule liquid chromatographic assay method utilizing a single-point external reference calibration. Approaches to reduce the required data to be collected and broaden the applicability of the methodology to a wide range of analytical methods is described. Finally, the application of the methodology to method development activities is discussed to aid in the identification of variability sources and effectively select replication strategies, thus allowing a holistic understanding of method variability throughout the entirety of the method lifecycle.


Assuntos
Controle de Qualidade , Calibragem , Reprodutibilidade dos Testes , Preparações Farmacêuticas/análise , Preparações Farmacêuticas/química , Cromatografia Líquida/métodos , Padrões de Referência , Indústria Farmacêutica/métodos , Técnicas de Química Analítica/métodos
3.
Sci Rep ; 14(1): 12655, 2024 06 02.
Artigo em Inglês | MEDLINE | ID: mdl-38825597

RESUMO

Potato peel waste (PPW) is an underutilized substrate which is produced in huge amounts by food processing industries. Using PPW a feedstock for production of useful compounds can overcome the problem of waste management as well as cost-effective. In present study, potential of PPW was investigated using chemical and thermochemical treatment processes. Three independent variables i.e., PPW concentration, dilute sulphuric acid concentration and liberation time were selected to optimize the production of fermentable sugars (TS and RS) and phenolic compounds (TP). These three process variables were selected in the range of 5-15 g w/v substrate, 0.8-1.2 v/v acid conc. and 4-6 h. Whole treatment process was optimized by using box-behnken design (BBD) of response surface methodology (RSM). Highest yield of total and reducing sugars and total phenolic compounds obtained after chemical treatment was 188.00, 144.42 and 43.68 mg/gds, respectively. The maximum yield of fermentable sugars attained by acid plus steam treatment were 720.00 and 660.62 mg/gds of TS and RS, respectively w.r.t 5% substrate conc. in 0.8% acid with residence time of 6 h. Results recorded that acid assisted autoclaved treatment could be an effective process for PPW deconstruction. Characterization of substrate before and after treatment was checked by SEM and FTIR. Spectras and micrographs confirmed the topographical variations in treated substrate. The present study was aimed to utilize biowaste and to determine cost-effective conditions for degradation of PWW into value added compounds.


Assuntos
Resíduos Industriais , Extratos Vegetais , Solanum tuberosum , Técnicas de Química Analítica/métodos , Técnicas de Química Analítica/normas , Solanum tuberosum/química , Extratos Vegetais/química , Extratos Vegetais/isolamento & purificação , Resíduos Industriais/análise , Indústria Alimentícia , Fermentação , Açúcares/análise , Açúcares/isolamento & purificação , Fenóis/análise , Fenóis/isolamento & purificação , Ácidos/química , Vapor , Espectroscopia de Infravermelho com Transformada de Fourier
4.
5.
Biosensors (Basel) ; 14(4)2024 Mar 29.
Artigo em Inglês | MEDLINE | ID: mdl-38667156

RESUMO

Covalent organic frameworks (COFs) are porous crystals that have high designability and great potential in designing, encapsulating, and immobilizing nanozymes. COF nanozymes have also attracted extensive attention in analyte sensing and detection because of their abundant active sites, high enzyme-carrying capacity, and significantly improved stability. In this paper, we classify COF nanozymes into three types and review their characteristics and advantages. Then, the synthesis methods of these COF nanozymes are introduced, and their performances are compared in a list. Finally, the applications of COF nanozymes in environmental analysis, food analysis, medicine analysis, disease diagnosis, and treatment are reviewed. Furthermore, we also discuss the application prospects of COF nanozymes and the challenges they face.


Assuntos
Estruturas Metalorgânicas , Estruturas Metalorgânicas/química , Técnicas Biossensoriais , Nanoestruturas , Química Analítica , Análise de Alimentos , Técnicas de Química Analítica/métodos
6.
Biosci Biotechnol Biochem ; 88(6): 639-647, 2024 May 22.
Artigo em Inglês | MEDLINE | ID: mdl-38544329

RESUMO

Efficient extraction of natural pigments is a key focus in enhancing the utilization of by-products for applications in the food industry. In this study, an enzymatic extraction method using Pectinex Ultra SP-L, Pectinex XXL, Novoshape, and Celluclast was used to investigate natural pigment production from the pomace of aronia, a commercially important plant. The method's performance was monitored using high-performance liquid chromatography with diode-array detection by measuring total and individual anthocyanin levels. Pectinex XXL (0.5%) yielded the highest total anthocyanin extraction (2082.41 ± 85.69 mg/100 g) in the single enzyme treatment, followed by Pectinex Ultra SP-L (0.05%), Celluclast (0.01%), and Novoshape (0.1%). Combining Pectinex XXL (0.25%) with Celluclast (0.01%) increased the extraction ratio of total anthocyanins (2 323.04 ± 61.32 mg/100 g) by ∼50.7% compared with that obtained using the solvent extraction method. This study demonstrated an effective enzymatic extraction method for application in the food industry.


Assuntos
Antocianinas , Técnicas de Química Analítica , Enzimas , Indústria Alimentícia , Antocianinas/análise , Antocianinas/isolamento & purificação , Técnicas de Química Analítica/métodos , Enzimas/metabolismo , Corantes de Alimentos/isolamento & purificação , Indústria Alimentícia/métodos , Photinia/química , Temperatura , Tempo
8.
Mikrochim Acta ; 191(4): 185, 2024 03 07.
Artigo em Inglês | MEDLINE | ID: mdl-38451330

RESUMO

A dual-mode sensor was developed for detecting acetylcholinesterase (AChE) and organophosphorus pesticides (OPs) via bifunctional BSA-CeO2 nanoclusters (NCs) with oxidase-mimetic activity and fluorescence property. The dual-mode sensor has the characteristics of self-calibration and self-verification, meeting the needs of different detection conditions and provide more accurate results. The colorimetric sensor and fluorescence sensor have been successfully used for detecting AChE with limit of detection (LOD) of 0.081 mU/mL and 0.056 mU/mL, respectively, while the LOD for OPs were 0.9 ng/mL and 0.78 ng/mL, respectively. The recovery of AChE was 93.9-107.2% and of OPs was 95.8-105.0% in actual samples. A novel strategy was developed to monitor pesticide residues and detect AChE level, which will motivate future work to explore the potential applications of multifunctional nanozymes.


Assuntos
Acetilcolinesterase , Técnicas de Química Analítica , Praguicidas , Smartphone , Acetilcolinesterase/análise , Hidrogéis , Compostos Organofosforados , Praguicidas/efeitos adversos , Técnicas de Química Analítica/métodos
9.
Eur J Pharm Sci ; 192: 106633, 2024 Jan 01.
Artigo em Inglês | MEDLINE | ID: mdl-37951317

RESUMO

Recently, the potentially highly carcinogenic N-nitrosamines (NAs) have become the focus of pharmaceutical regulatory authorities, the pharmaceutical industry and researchers because trace amounts have been detected in some drug products (DPs), resulting in drug supply shortages. In the absence of sufficient analytical methods for the determination of multiple regulated low-molecular-weight NAs in various DPs, a robust, selective, sensitive and accurate method based on sample preparation by solid phase extraction, followed by liquid chromatography high-resolution mass spectrometry for the simultaneous analysis of 13 regulated low-molecular-weight NAs was developed. The best results for the cleanup were obtained using Strata X-C SPE cartridge. The proposed method was successfully validated according to the USP general chapter 〈1469〉, demonstrating its excellent linearity, accuracy and precision in wide analytical ranges, adjusted to NAs acceptable intake limits. The achieved limits of quantitation correspond to 30 % or less of the acceptable intake limits. The developed analytical method was applied to 16 commercially available DPs containing one to three active pharmaceutical ingredients with different physicochemical properties. Only N-Nitrosodimethylamine was detected in DPs containing ranitidine at levels exceeding the regulatory AI limits by 37.6 - 57.4-fold. In addition, the robustness of the method was confirmed on a considerable number of DPs containing different active ingredients, demonstrating the suitability of the analytical method for routine quality control of different DPs, thus mitigate the risk to human health.


Assuntos
Técnicas de Química Analítica , Nitrosaminas , Preparações Farmacêuticas , Humanos , Cromatografia Líquida de Alta Pressão/métodos , Cromatografia Líquida , Espectrometria de Massas , Nitrosaminas/análise , Preparações Farmacêuticas/química , Extração em Fase Sólida/métodos , Técnicas de Química Analítica/métodos
10.
J Biol Chem ; 300(2): 105615, 2024 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-38159850

RESUMO

Cells continuously fine-tune signaling pathway proteins to match nutrient and stress levels in their local environment by modifying intracellular proteins with O-linked N-acetylglucosamine (O-GlcNAc) sugars, an essential process for cell survival and growth. The small size of these monosaccharide modifications poses a challenge for functional determination, but the chemistry and biology communities have together created a collection of precision tools to study these dynamic sugars. This review presents the major themes by which O-GlcNAc influences signaling pathway proteins, including G-protein coupled receptors, growth factor signaling, mitogen-activated protein kinase (MAPK) pathways, lipid sensing, and cytokine signaling pathways. Along the way, we describe in detail key chemical biology tools that have been developed and applied to determine specific O-GlcNAc roles in these pathways. These tools include metabolic labeling, O-GlcNAc-enhancing RNA aptamers, fluorescent biosensors, proximity labeling tools, nanobody targeting tools, O-GlcNAc cycling inhibitors, light-activated systems, chemoenzymatic labeling, and nutrient reporter assays. An emergent feature of this signaling pathway meta-analysis is the intricate interplay between O-GlcNAc modifications across different signaling systems, underscoring the importance of O-GlcNAc in regulating cellular processes. We highlight the significance of O-GlcNAc in signaling and the role of chemical and biochemical tools in unraveling distinct glycobiological regulatory mechanisms. Collectively, our field has determined effective strategies to probe O-GlcNAc roles in biology. At the same time, this survey of what we do not yet know presents a clear roadmap for the field to use these powerful chemical tools to explore cross-pathway O-GlcNAc interactions in signaling and other major biological pathways.


Assuntos
Acetilglucosamina , Técnicas de Química Analítica , Transdução de Sinais , Acetilglucosamina/análise , Acetilglucosamina/metabolismo , Técnicas de Química Analítica/métodos , Receptores Acoplados a Proteínas G/metabolismo , Bioquímica/métodos , Biotecnologia/métodos
SELEÇÃO DE REFERÊNCIAS
DETALHE DA PESQUISA
...