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1.
Nutrients ; 13(8)2021 Aug 09.
Artigo em Inglês | MEDLINE | ID: mdl-34444894

RESUMO

Nutritional intake has important impacts on human health. A sufficient supply of nutrients is required to ensure high-level nutrition in a population. Assessment of nutrient supply adequacy can help to develop evidence-based policies and thereby promote public health. This study estimates the supply adequacy of nutrients in China's food system from 1965 to 2018 at the national level, aiming to reveal whether the supply of nutrients meets the demand. The results show that the nutrient supply in China's food system has experienced a sharp increase in the past five decades, and the deficiency in nutrient supply has been greatly mitigated. Although most nutrients such as potassium are already sufficiently supplied in China's current food system, some nutrients, especially calcium and zinc, still need a further enlarged supply to improve the nutrition condition of the Chinese population. Besides encouraging a healthy diet, supply-side regulation, e.g., fortification and enrichment, is also needed to improve nutrient availability. This study helps people better understand the development and current situation of nutrient adequacy in China's food supply, thereby providing information and implications for policymakers.


Assuntos
Dieta Saudável/tendências , Análise de Alimentos/estatística & dados numéricos , Abastecimento de Alimentos/estatística & dados numéricos , Nutrientes/análise , China , Análise de Alimentos/métodos , Abastecimento de Alimentos/história , História do Século XX , História do Século XXI , Humanos , Inquéritos Nutricionais
2.
Molecules ; 26(15)2021 Jul 28.
Artigo em Inglês | MEDLINE | ID: mdl-34361713

RESUMO

The textural properties of butter are influenced by its fat content and implicitly by the fatty acids composition. The impact of butter's chemical composition variation was studied in accordance with texture and color properties. From 37 fatty acids examined, only 18 were quantified in the analyzed butter fat samples, and approximately 69.120% were saturated, 25.482% were monounsaturated, and 5.301% were polyunsaturated. The butter samples' viscosity ranged between 0.24 and 2.12 N, while the adhesiveness ranged between 0.286 to 18.19 N·mm. The principal component analysis (PCA) separated the butter samples based on texture parameters, fatty acids concentration, and fat content, which were in contrast with water content. Of the measured color parameters, the yellowness b* color parameter is a relevant indicator that differentiated the analyzed sample into seven statistical groups; the ANOVA statistics highlighted this difference at a level of p < 0.001.


Assuntos
Manteiga/análise , Ácidos Graxos Insaturados/química , Ácidos Graxos/química , Água/análise , Animais , Cor , Ácidos Graxos/classificação , Ácidos Graxos/isolamento & purificação , Ácidos Graxos Insaturados/classificação , Ácidos Graxos Insaturados/isolamento & purificação , Análise de Alimentos/métodos , Humanos , Análise de Componente Principal , Paladar/fisiologia , Viscosidade
3.
Molecules ; 26(16)2021 Aug 17.
Artigo em Inglês | MEDLINE | ID: mdl-34443568

RESUMO

Laser-Induced Breakdown Spectroscopy (LIBS), having reached a level of maturity during the last few years, is generally considered as a very powerful and efficient analytical tool, and it has been proposed for a broad range of applications, extending from space exploration down to terrestrial applications, from cultural heritage to food science and security. Over the last decade, there has been a rapidly growing sub-field concerning the application of LIBS for food analysis, safety, and security, which along with the implementation of machine learning and chemometric algorithms opens new perspectives and possibilities. The present review intends to provide a short overview of the current state-of-the-art research activities concerning the application of LIBS for the analysis of foodstuffs, with the emphasis given to olive oil, honey, and milk.


Assuntos
Produtos Biológicos/química , Análise de Alimentos/métodos , Mel/análise , Lasers , Leite/química , Azeite de Oliva/química , Análise Espectral , Animais
4.
Molecules ; 26(16)2021 Aug 08.
Artigo em Inglês | MEDLINE | ID: mdl-34443389

RESUMO

Is it possible to characterize the types of honey based on their chemical composition, their content of bioactive substances, and their physicochemical properties? The objective of this study was a comparative analysis of four types of honey from the Carpathian Foothills area, located in south-east Poland, based on the content of the main phenolic acids and proline, the mineral composition, and selected physicochemical properties. Most analyses, such as those of phenolic acids, sugars, and proline content, in honey samples were performed using chromatographic methods. These experiments demonstrated that honeydew honeys were the richest in phenolic acids, minerals, as well as oligosaccharides, compared to other honeys. Dark-colored honeys were characterized by the highest proline content. The dominant elements in all types of honey were potassium and calcium. The results of the present study show that analyses of specific phenolic acids, minerals, proline, and sugar content, in combination with chemometrics analysis, may successfully differentiate between the biological origins of honey samples and allow the preliminary verification of the samples before performing time-consuming pollen analysis.


Assuntos
Fenômenos Químicos , Análise de Alimentos/métodos , Mel/análise , Informática
5.
ACS Appl Mater Interfaces ; 13(33): 39905-39914, 2021 Aug 25.
Artigo em Inglês | MEDLINE | ID: mdl-34374514

RESUMO

The lack of functional groups or binding sites largely hindered the broad application of microporous organic networks (MONs). Herein, we report the fabrication of the sulfonate group-enriched magnetic MON composite (MMON-SO3H@SO3Na) via the combination of the sulfonic acid group containing the monomer and thiol-yne click postmodification for efficient magnetic solid-phase extraction (MSPE) of benzimidazole fungicides (BZDs) from complex sample matrices. The well-defined core-shell-structured MMON-SO3H@SO3Na was obtained and served as an advanced adsorbent for MSPE for concentrating and monitoring trace BZDs. The MMON-SO3H@SO3Na with numerous sulfonate groups provides plenty of ion-exchange, hydrogen-bonding, and π-π sites, leading to the favorable affinity to BZDs via multiple interaction mechanisms. The MMON-SO3H@SO3Na-based MSPE-high-performance liquid chromatography method afforded a wide linear range, low limits of detection, large enrichment factors, good precisions, and reusability for BZDs. Trace BZDs in complex vegetables and fruit samples were successfully detected by the established method. The MMON-SO3H@SO3Na also exhibited good selectivity toward multiple types of polar contaminants containing hydrogen-bonding sites and aromatic structures. This work provided a new postsynthesis strategy for constructing novel and multifunctioned magnetic MONs for preconcentration of trace analytes in a complex matrix.


Assuntos
Alcanossulfonatos/síntese química , Alcinos/química , Benzimidazóis/isolamento & purificação , Análise de Alimentos/métodos , Fungicidas Industriais/isolamento & purificação , Compostos de Sulfidrila/química , Cromatografia Líquida de Alta Pressão/métodos , Química Click , Óxido Ferroso-Férrico/química , Frutas/química , Limite de Detecção , Magnetismo/métodos , Microesferas , Porosidade , Reprodutibilidade dos Testes , Extração em Fase Sólida/métodos , Verduras/química
6.
Molecules ; 26(15)2021 Jul 29.
Artigo em Inglês | MEDLINE | ID: mdl-34361757

RESUMO

Detection of relevant contaminants using screening approaches is a key issue to ensure food safety and respect for the regulatory limits established. Electrochemical sensors present several advantages such as rapidity; ease of use; possibility of on-site analysis and low cost. The lack of selectivity for electrochemical sensors working in complex samples as food may be overcome by coupling them with molecularly imprinted polymers (MIPs). MIPs are synthetic materials that mimic biological receptors and are produced by the polymerization of functional monomers in presence of a target analyte. This paper critically reviews and discusses the recent progress in MIP-based electrochemical sensors for food safety. A brief introduction on MIPs and electrochemical sensors is given; followed by a discussion of the recent achievements for various MIPs-based electrochemical sensors for food contaminants analysis. Both electropolymerization and chemical synthesis of MIP-based electrochemical sensing are discussed as well as the relevant applications of MIPs used in sample preparation and then coupled to electrochemical analysis. Future perspectives and challenges have been eventually given.


Assuntos
Técnicas Biossensoriais , Técnicas Eletroquímicas , Análise de Alimentos/métodos , Contaminação de Alimentos/análise , Impressão Molecular/métodos , Polímeros Molecularmente Impressos/síntese química , Animais , Toxinas Bacterianas/análise , Análise de Alimentos/instrumentação , Inocuidade dos Alimentos/métodos , Humanos , Micotoxinas/análise , Praguicidas/análise , Polimerização , Extração em Fase Sólida/métodos , Drogas Veterinárias/análise
7.
Nutrients ; 13(8)2021 Aug 02.
Artigo em Inglês | MEDLINE | ID: mdl-34444844

RESUMO

The implementation of REGULATION (EC) No 1924/2006 has led to the formation of a list of health claims that can be used in food supplements (EU 432/2012). However, such supplements are often composed of plant preparations with claims omitted from this list. The peculiarity of plants is related to their long history of use, that could allow claims based on traditionally recognized health effects. In addition, the scientific literature has been enriched over the years through clinical studies that have assessed the bioavailability and efficacy of bioactive components, and investigated their mechanisms of action. Based on existing recognized models which aim to classify research according to the level of scientific evidence, Synadiet developed a three-grade model (A, B or C) for assessing plants health claims. In this paper, the applicability of the model is illustrated through an example for which a Grade B health claim attesting the possible contribution of red clover isoflavones to the improvement of blood lipid levels in postmenopausal women has been attributed. The model appears able to be easily extrapolated to claims pertaining to other plants. If adopted by consensus at European level, this model could initiate the implementation of a positive list of health claims on plant preparations.


Assuntos
Suplementos Nutricionais/normas , Análise de Alimentos/métodos , Rotulagem de Alimentos/normas , Preparações de Plantas/normas , Plantas Comestíveis , Adulto , Idoso , Suplementos Nutricionais/análise , Feminino , Rotulagem de Alimentos/legislação & jurisprudência , Humanos , Isoflavonas/análise , Isoflavonas/normas , Legislação sobre Alimentos , Lipídeos/sangue , Masculino , Pessoa de Meia-Idade , Valor Nutritivo , Preparações de Plantas/análise , Pós-Menopausa/sangue , Trifolium/química
8.
Molecules ; 26(14)2021 Jul 17.
Artigo em Inglês | MEDLINE | ID: mdl-34299609

RESUMO

In a global context where trading of wines involves considerable economic value, the requirement to guarantee wine authenticity can never be underestimated. With the ever-increasing advancements in analytical platforms, research into spectroscopic methods is thriving as they offer a powerful tool for rapid wine authentication. In particular, spectroscopic techniques have been identified as a user-friendly and economical alternative to traditional analyses involving more complex instrumentation that may not readily be deployable in an industry setting. Chemometrics plays an indispensable role in the interpretation and modelling of spectral data and is frequently used in conjunction with spectroscopy for sample classification. Considering the variety of available techniques under the banner of spectroscopy, this review aims to provide an update on the most popular spectroscopic approaches and chemometric data analysis procedures that are applicable to wine authentication.


Assuntos
Vinho/análise , Análise de Alimentos/métodos , Aprendizado de Máquina , Espectroscopia de Ressonância Magnética/métodos , Análise Multivariada , Espectrometria de Fluorescência/métodos , Espectrofotometria Infravermelho/métodos , Espectrofotometria Ultravioleta/métodos , Análise Espectral Raman/métodos
9.
Se Pu ; 39(2): 162-172, 2021 Feb.
Artigo em Chinês | MEDLINE | ID: mdl-34227349

RESUMO

Food safety is closely related to human health and life. Contaminated foods may result in illness or poisoning. For example, perfluorinated compounds can concentrate in the human body, or they can be transferred to the baby during breastfeeding, thus leading to serious health risks. Phthalate esters may cause damage to the liver, lungs, and kidneys. Therefore, food safety has become a hot topic at a global level. Poisonous and harmful substances in foods are derived from the environment, planting or breeding, food contacting materials, and food processing, or due to unsuitable storage conditions. Residues of pesticides and veterinary drugs, organic pollutants, additives, heavy metals, and biotoxins often hamper food safety, causing diseases or even death. The diversity of available food species, complexity of the sample matrix, and lack of information about the source of pollutants render the direct determination of food contaminants difficult. Pretreatment is vital for the accurate analysis of trace toxins in foods. Optimal pretreatment can not only improve the extract efficiency and determination sensitivity, but also prevent instrument contamination. Pretreatment techniques have played an important role in trace determination for complex matrices. Pretreatment methods can be classified as solvent-based and adsorption-based methods. Adsorption-based techniques such as solid-phase extraction, magnetic solid-phase extraction, and solid-phase microextraction are simple and efficient, and hence, are widely used. In these pretreatment techniques, adsorbents play a key role in the extraction effect. In the last few years, metal organic frameworks, metal oxide materials, carbon nanotubes, graphene, and magnetic nanoparticles, as well as a combination of these materials, have been used as adsorbents. These materials are porous and have a large surface area; they are used to enrich trace targets and eliminate interferents. Covalent organic polymers (COPs) are a class of organic porous materials constructed from organic monomers via covalent bonding. Given their excellent characteristics such as light density, good stability, high surface area, structural controllability, and ease of modification, COPs are potential adsorbents. COPs are often synthesized by solvent thermal methods. However, these methods are time-consuming and require toxic solvents and harsh reaction conditions. As alternatives, room-temperature methods, mechanical chemical methods, microwave-assisted methods, and UV-assisted methods have been developed. This has facilitated the synthesis of a wide range of COPs. In this article, the recent applications of COPs in sample pretreatment for food safety analysis are reviewed. COPs can be used in solid-phase extraction by simple packing into columns, polymerization, or chemical bonding in the capillary. Magnetic compounds have been prepared by one-pot synthesis, in situ growth, in situ reduction, or coprecipitation methods and used in magnetic solid-phase extraction. Coatings of solid-phase microextraction fibers are fabricated by physical methods, chemical bonding, sol-gel methods, or in situ growth. Toxic and harmful substances in foods and foodstuffs are efficiently extracted by exploiting the high adsorbent capacities and specificity of COPs. Future development prospects and challenges in sample pretreatment are also discussed herein. There is increased focus on the development of simple, efficient, and environment-friendly methods to synthesize COPs with specific functions; further, high-throughput, sensitive analytical methods may be established. In the future, more specific COPs will be prepared in a cost-effective manner for widespread use in sample pretreatment.


Assuntos
Análise de Alimentos/métodos , Inocuidade dos Alimentos , Estruturas Metalorgânicas , Nanotubos de Carbono , Análise de Perigos e Pontos Críticos de Controle , Polímeros , Extração em Fase Sólida
10.
Se Pu ; 39(1): 96-103, 2021 Jan.
Artigo em Chinês | MEDLINE | ID: mdl-34227363

RESUMO

In this study, a comprehensive analytical method based on gas chromatography-tandem mass spectrometry (GC-MS/MS) was developed for the determination of nine N-nitrosamines in animal derived foods. There are many kinds of N-nitrosamines in foods that are harmful to human health. However, the national standard GB 5009.26-2016 pertains only to the detection of N-dimethylnitrosamine; there are many drawbacks of this method, such as complicated sample preparation, low recovery rate, and poor reproducibility. Hence, it is of practical significance to establish a method for the simultaneous determination of a variety of N-nitrosamines. The optimal extraction conditions for the developed method were as follows: 10.0 g aliquots of the sample were placed in a 50 mL centrifuge tube, followed by the addition of 10 mL acetonitrile and 200 µL internal working standard solutions. After 30 min of freezing treatment, 4 g magnesium sulfate and 1 g sodium chloride were added for dehydration, and the tube was centrifuged at 9000 r/min for 5 min. After vortex centrifugation, 5 mL of the clear supernatant was purified using 150 mg polystyrene divinylbenzene (PLS-A). The purified extracts were dewatered using 1.6 g MgSO4 and 0.4 g NaCl, and then filtered through a 0.22 µm membrane filter unit prior to GC-MS/MS analysis. Temperature-programmed was applied at an initial temperature of 50 ℃. After 0.16 min, the temperature was raised to 220 ℃ at the rate of 900 ℃/min for 5 min. N-Nitrosamines were separated on an HP-Innowax column (30 m×0.25 mm×0.25 µm). Identification and quantification were achieved using an electron impact ion (EI) source in positive ion mode with multiple reaction monitoring (MRM). The internal standard method was used to quantify the N-nitrosamines. Under the optimal conditions, the correlation coefficients of the standard calibration curves were not less than 0.99 in the range of 0.1-50.0 µg/L. The limits of detection were 0.03-0.30 µg/kg (S/N=3), and limits of quantification were 0.15-1.00 µg/kg (S/N=10). At spiked levels of 0.5, 1.0, and 3.0 µg/kg, the average recoveries of N-nitrosamines in spiked samples ranged from 80.4% to 98.5%, with relative standard deviations between 2.41% and 12.50%. This method was used to determine animal derived food products, except N-itrosomethylethylamine and N-nitrosomorpholine, others were founded. The results showed that N-nitrosamines levels in salted aquatic products were generally higher than those of the other samples. The method established in this study is simple to operate, and it does not require any time-consuming distillation extraction. Furthermore, there is minimal consumption of samples and reagents; consequently, the experiment cost is reduced, and the method is environmentally friendly. This method has theoretical and practical significance for the control of N-nitrosamines residues in animal derived foods, establishment of detection standards, and corresponding management measures.


Assuntos
Análise de Alimentos/métodos , Nitrosaminas , Animais , Cromatografia Gasosa-Espectrometria de Massas , Isótopos , Nitrosaminas/análise , Reprodutibilidade dos Testes , Espectrometria de Massas em Tandem
11.
Se Pu ; 39(5): 472-477, 2021 May.
Artigo em Chinês | MEDLINE | ID: mdl-34227331

RESUMO

In recent years, goat milk powder and camel milk powder have gained popularity among consumers. Due to their potential low allergenicity, these milk powders have become a substitute for breast milk, especially for infants, and for people with lactose intolerance. In this paper, a method was developed for the simultaneous determination of 18 amino acids (AAs), histidine (His), serine (Ser), arginine (Arg), glycine (Gly), aspartic acid (Asp) combined with asparagine (Asn), glutamic (Glu), glutamine (Gln), threonine (Thr), alanine (Ala), proline (Pro), lysine (Lys), tyrosine (Tyr), methionine (Met), valine (Val), isoleucine (Iso), leucine (Leu), and dimer of cysteine (Cys) combined with cysteine (L-Cys-Cys), phenylalanine (Phe), taurine (Tau) in milk, goat milk, and camel milk power. The aim of the research was to compare the three kinds of milk powder from the perspective of the constituent amino acids. Therefore, the amino acid compositions and contents were compared. Thus, 2.0 g of the sample was accurately weighed, added to 16 mL H2O, and mixed thoroughly. Then, 200 mg of the sample was weighed in a glass tube with a stream of nitrogen to displace oxygen. The samples were hydrolyzed in HCl for 24 h at 110 ℃. Then, the amino acids were pre-column derivatized by 6-aminoquinoline-n-hydroxysuccinimide carbamate (AQC). In precolumn derivatization combined with reverse-phase chromatography, both 2,4-dinitrofluorobenzene (DNFB) and phenylisothiocyanate (PITC) can react with primary amines and secondary amines. However, the derivatization time is approximately 1 h. In contrast, the derivatization time of AQC was greatly shortened. Derivatization led to the conversion of free amino acids into highly stable derivatives, which were separated by ultra performance liquid chromatography (UPLC) with UV detection at 260 nm and quantified by the external standard method. The samples were separated on a BEH C18 column (150 mm×2.1 mm, 1.7 µm) at a flow rate of 0.4 mL/min. The calibration curves showed good linearity, with correlation coefficients greater than 0.999. The limits of detection (LODs) and limits of quantification (LOQs) of the 18 amino acids were 1.3-2.5 (mg/100 g) and 3.9-7.5 (mg/100 g), respectively. Quality control samples of SRM 1849a were used as the reference material. The results were in accordance with the content range. The RSDs ranged from 2.04% to 3.65%. Furthermore, the developed method was successfully applied to determine the types and concentrations of amino acids in 11 samples purchased from local markets in Shanghai and online shops. Abundant amino acids were detected in the three types of milk powder. While all the milk powder samples contained 18 types of amino acids, Tau was not detected in some of the goat and camel milk powder samples. Total essential amino acids (TEAA) in total amino acids (TAA) of milk powder was the highest of all. The TEAA values of TAA in the goat and camel milk powders were similar. The developed method requires only 22 min for the separation of 18 amino acids. This method is suitable for the large-scale analysis of milk powder samples, and it demonstrates high sensitivity and accuracy for the determination and confirmation of the 18 amino acids in different types of milk powders.


Assuntos
Aminoácidos , Análise de Alimentos/métodos , Leite , Aminoácidos/análise , Animais , Cromatografia Líquida de Alta Pressão , Cromatografia Líquida , Leite/química , Pós
12.
Se Pu ; 39(5): 494-509, 2021 May.
Artigo em Chinês | MEDLINE | ID: mdl-34227334

RESUMO

QuEChERS pretreatment combined with gas chromatography-quadrupole time-of-flight mass spectrometry (GC-Q-TOF/MS) has been investigated for application in screening 244 pesticide residues in chilli. Fresh chilli samples were extracted with acetonitrile, and dried chilli samples were extracted using an acetonitrile/acetic acid (99∶1, v/v) mixture. The two extraction solvents were stored at -20 ℃. After salting out and cleaning by dispersive solid phase extraction (dSPE), heptachlor epoxide B was added as an internal standard, and the resulting residues were dissolved in 1.00 mL acetone. The dissolved sample solution was loaded onto an HP-5MS UI column (30 m×0.25 mm, 0.25 µm) and eluted by GC-Q-TOF/MS with a programmable temperature vaporizer and splitless injection in the full-scan mode. The compensation effects of the analytical protectant (AP) and matrix-matched calibration method on the matrix effect were established. AP could be used in the fresh chilli matrix to compensate for matrix effects, but it was not effective in the dried chilli matrix. The matrix-matched calibration method was effective in both matrices, which was selected for the quantification of pesticide residues in the samples. Because of the existence of the isomers of one compound and the same characteristic ions of different compounds, analyte detection was based on a flexible retention time deviation of ±0.25 min and accurate mass deviation of ±20×10 -6. Screening was performed by the software in the automatic matching mode. Compound identification and quantitation were based on a database and calibration curve established with reference materials. Suspicious samples were subjected to manual analysis. Quantitative analysis of 244 pesticide residues in fresh chilli and 222 pesticide residues in dried chilli was performed. The results showed that the developed database and method can provide a reference for the high-throughput screening and quantitation of fresh and dried chilli. Different levels of pesticides were added to the blank chilli samples, and the addition level corresponding to a signal-to-noise ratio (S/N) of 10 was used as the limit of quantification (LOQ). The LOQs of 44 pesticides with a maximum residue limit (MRL) ≤0.05 mg/kg in fresh chilli did not exceed 0.010 mg/kg. The linear ranges of these 44 pesticides were 0.01-1.00 mg/L. At spiked levels of the LOQ and 2.5 times the LOQ, the ratios of the 44 pesticides with recoveries of 60% to 120% were 88.64% and 100%, respectively. The LOQs of 200 pesticides with MRLs ≥0.05 mg/kg or without MRLs in fresh chilli did not exceed 0.025 mg/kg. The linear ranges of these 200 pesticides were 0.05-1.00. At spiked levels of the LOQ, twice the LOQ, and 10 times the LOQ, the ratios of the 200 pesticides with recoveries of 60% to 120% were 49.50%, 87.00%, and 89.50%, respectively. The linear correlation coefficients (r 2) of the 244 pesticides in fresh chilli were greater than 0.99. The LOQs of 222 pesticides in dried chilli were less than 0.15 mg/kg, and the linear ranges were 0.04-1.00 mg/L. The ratios of these 222 pesticides with r 2 greater than 0.99 was 95.46%. At spiked levels of the LOQ, twice the LOQ and 10 times the LOQ in dried chilli, the ratio of the 222 pesticides with recoveries of 60% to 120% were 72.52%, 73.42%, and 81.53%, respectively. The established screening and confirmation method was used to analyze 12 fresh chilli samples and 14 dried chilli samples. Eight pesticides were found in nine fresh chilli samples and three dried chilli samples, all of which were confirmed to be positive after manual identification. The concentrations of these pesticides were lower than the MRLs required by GB 2763-2019: National Food Safety Standard Maximum Residue Limits for Pesticides in Food. The results demonstrate that the established method is rapid, easy to execute, efficient, and reliable. It can be used for the high-throughput screening and quantitation of pesticide residues in fresh and dried chilli.


Assuntos
Análise de Alimentos/métodos , Contaminação de Alimentos/análise , Resíduos de Praguicidas , Calibragem , Cromatografia Gasosa-Espectrometria de Massas , Carne/análise , Resíduos de Praguicidas/análise , Extração em Fase Sólida
13.
Se Pu ; 39(5): 526-533, 2021 May.
Artigo em Chinês | MEDLINE | ID: mdl-34227337

RESUMO

Ginsenosides are the main active compounds of ginseng, American ginseng and Panax notoginseng. They have certain pharmacological effects on the cardiovascular, immune and central nervous systems. Most ginsenosides are naturally classified as protopanaxatriol (PPT), protopanaxadiol (PPD), and oleanolic acid (OA) according to their aglycone skeletons. The nine main ginsenosides are Rb1, Rb2, Rb3, Rc, Rd, Re, Rf, Rg1 and Rg2. Accurate quantification of ginsenosides is imperative because they are the characteristic components and quality evaluation indicators of health foods. A new method based on solid phase extraction-ultra performance liquid chromatography-tandem mass spectrometry (SPE-UPLC-MS/MS) was developed for the determination of the nine ginsenosides in health foods. First, the pretreatment conditions were optimized. With the aim of purifying the samples and removing impurities, SPE cartridges with different packing materials, such as Alumina-N/XAD-2 SPE Cartridge, C18 and HLB were investigated. Based on the purification efficiencies, recoveries and other factors, the Alumina-N/XAD-2 SPE cartridge composite SPE column was selected as the pretreatment purification column. The eluents were then optimized. When water was used as the eluent, the ginsenosides could remain adsorbed on the SPE column, and could not be eluted down with other water-soluble substances. By increasing the proportion of ethanol in the eluent, the ginsenoside adsorbed on the filler of the SPE column could be gradually eluted. When the proportion of ethanol in the eluent reached 70%, the ginsenosides could be completely eluted. The effects of different volumes of 70% ethanol elution solvent (5-30 mL) on the extraction efficiencies of ginsenosides were also investigated. The results showed that when the volume of the elution solvent reached 20 mL, the ginsenosides were completely eluted. Then, the chromatographic conditions and MS parameters were optimized. By examining the ionization cracking of ginsenosides, the quasi-molecular ions and corresponding fragment ions in ginsenoside primary MS were determined. After optimizing the chromatographic conditions and MS parameters, not only the sensitivity of the method was improved, but also the isomers Rb2, Rb3 and Rc with the same quasi-molecular ions and the corresponding fragment ions were completely separated. Good separation was achieved for the nine ginsenosides, thus meeting the requirements for accurate quantification. Finally, chromatographic separation was achieved on a Hypersil Gold C18 column (100 mm×2.1 mm, 1.9 µm) under linear gradient elution using a 5 mmol/L ammonium acetate solution (with 0.1% formic acid) and acetonitrile as the mobile phases. The nine ginsenosides were detected using a triple quadrupole MS detector under ESI - and multiple reaction monitoring (MRM) modes, and quantified by the external standard method. The nine ginsenosides showed a strong positive linear correlation (r 2>0.9950) in the range of 0.005-0.5 µg/mL. The sample recoveries and the corresponding relative standard deviations (RSDs) were 81.1%-114.2% and 0.4%-8.0% (n=6), respectively. Eleven batches of health foods on the market, among which six batches contained ginseng, American ginseng or Panax notoginseng ingredients, were analyzed by the developed method, and the ginsenosides were detected. The total ginsenosides contents were close to those mentioned on the label. However, the nine ginsenosides were detected in one batch of health food, whose label did not indicated ginseng, American ginseng or Panax notoginseng. The nine ginsenosides were not detected in the remaining batches of health foods.The health food extract was directly loaded and purified without any complex pretreatment. The UPLC⁃MS/MS method, not only helped shorten the analysis time, but also accurate quantification of low ginsenoside contents in complex matrix samples. The developed method is simple and rapid, with high throughput, thus being suitable for the quantitative analysis of the nine ginsenosides in health foods.


Assuntos
Análise de Alimentos/métodos , Ginsenosídeos , Panax , Cromatografia Líquida de Alta Pressão , Ginsenosídeos/análise , Espectrometria de Massas em Tandem
14.
Food Chem ; 361: 130173, 2021 Nov 01.
Artigo em Inglês | MEDLINE | ID: mdl-34062455

RESUMO

Glutathione and its disulfide were determined in a single run using liquid chromatography with on-line post-column derivatization and fluorimetric detection (340 nm/425 nm). The analytes were separated using a reversed-phase column capable of operating at 100% aqueous mobile phase and detected following direct on-line reaction with o-phthalaldehyde (7.5 mmol L-1) in highly basic medium (0.37 mol L-1 NaOH). The instrumental and chemical variables were carefully investigated towards high sensitivity and throughput, while special attention was paid to validating potential matrix effects. Glutathione and its disulfide could be selectively determined with respective LODs of 0.10 and 0.30 µmol L-1 in the absence of matrix effect (<6%). The endogenous content of the analytes was accurately determined in various food samples with recoveries ranging between 80 and 120% in all cases. The proposed method is reliable and promising as a generic analytical tool for the convenient estimation of the redox status of glutathione in various food matrices.


Assuntos
Cromatografia Líquida/métodos , Análise de Alimentos/métodos , Dissulfeto de Glutationa/análise , Glutationa/análise , Cromatografia Líquida de Alta Pressão/métodos , Limite de Detecção , Oxirredução , Verduras/química , Vinho/análise , o-Ftalaldeído/química
15.
Food Chem ; 361: 130154, 2021 Nov 01.
Artigo em Inglês | MEDLINE | ID: mdl-34077882

RESUMO

The implementation of Raman and infrared spectroscopy with three data fusion strategies to predict pH and % IMF content of red meat was investigated. Raman and FTIR systems were utilized to assess quality parameters of intact red meat. Quantitative models were built using PLS, with model performances assessed with respect to the determination coefficient (R2), root mean square error and normalized root mean square error (NRMSEP). Results obtained on validation against an independent test set show that the high-level fusion strategy had the best performance in predicting the observed pH; with RP2 and NRMSEP values of 0.73 and 12.9% respectively, whereas low-level fusion strategy showed promise in predicting % IMF (NRMSEP = 8.5%). The fusion of data from more than one technique at low and high level resulted in improvement in the model performances; highlighting the possibility of information enhancement.


Assuntos
Análise de Alimentos/métodos , Carne Vermelha/análise , Espectroscopia de Infravermelho com Transformada de Fourier/métodos , Análise Espectral Raman/métodos , Animais , Qualidade dos Alimentos , Concentração de Íons de Hidrogênio , Processamento de Sinais Assistido por Computador
16.
Food Chem ; 361: 130149, 2021 Nov 01.
Artigo em Inglês | MEDLINE | ID: mdl-34082385

RESUMO

Fluorescence spectroscopy is rapid, straightforward, selective, and sensitive, and can provide the molecular fingerprint of a sample based on the presence of various fluorophores. In conjunction with chemometrics, fluorescence techniques have been applied to the analysis and classification of an array of products of agricultural origin. Recognising that fluorescence spectroscopy offered a promising method for wine authentication, this study investigated the unique use of an absorbance-transmission and fluorescence excitation emission matrix (A-TEEM) technique for classification of red wines with respect to variety and geographical origin. Multi-block data analysis of A-TEEM data with extreme gradient boosting discriminant analysis yielded an unrivalled 100% and 99.7% correct class assignment for variety and region of origin, respectively. Prediction of phenolic compound concentrations with A-TEEM based on multivariate calibration models using HPLC reference data was also highly effective, and overall, the A-TEEM technique was shown to be a powerful tool for wine classification and analysis.


Assuntos
Análise de Alimentos/métodos , Aprendizado de Máquina , Fenóis/análise , Vinho/análise , Austrália , Cromatografia Líquida de Alta Pressão/métodos , Análise Discriminante , Análise de Alimentos/estatística & dados numéricos , Espectrometria de Fluorescência , Vitis/química
17.
Food Chem ; 361: 129829, 2021 Nov 01.
Artigo em Inglês | MEDLINE | ID: mdl-34087571

RESUMO

To detect major soy isoflavone glycosides, namely daidzin (DZ) and genistin (GEN), novel open sandwich fluorescence-linked immunosorbent assay (os-FLISA) was developed by taking advantage of enhanced interactions between variable regions of heavy (VH) and light chain (VL) domains in the presence of an antigen. The VH and VL genes were expressed in Escherichia coli as a chimera protein with green fluorescence protein (AcGFP1) and maltose-binding protein (MBP), respectively. Comprehensive characterization of os-FLISA displayed nearly the same specificity as parental DZ- and GEN-specific monoclonal antibody, demonstrating the potential of the developed assay for detection of both DZ and GEN. Their detectable range in this system exhibited at 0.1-12.5 µg mL-1. Subsequent validation analysis revealed that os-FLISA was reliable and accurate system for detection of total soy isoflavone glycosides. Notably, this is the first FLISA based on an open sandwich system, which can be employed for the detection of small molecules.


Assuntos
Técnicas de Imunoadsorção , Isoflavonas/análise , Soja/química , Anticorpos Monoclonais/genética , Escherichia coli/genética , Fluorescência , Análise de Alimentos/métodos , Proteínas de Fluorescência Verde/genética , Cadeias Pesadas de Imunoglobulinas/genética , Cadeias Leves de Imunoglobulina/genética , Isoflavonas/imunologia , Limite de Detecção , Proteínas Ligantes de Maltose/genética , Proteínas Recombinantes/genética , Reprodutibilidade dos Testes
18.
Spectrochim Acta A Mol Biomol Spectrosc ; 262: 120081, 2021 Dec 05.
Artigo em Inglês | MEDLINE | ID: mdl-34175755

RESUMO

The demand for gluten-free banana flour has led manufactures to enforce strict measures for quality control. A need has arisen for the development of more sensitive and reliable methods to test the quality of green banana flour (GBF). The objective of this study was to develop rapid visible to near-infrared (Vis-NIR) based spectroscopic models to detect gluten concentration, as a biomarker to detect wheat flour adulteration in green banana flour (GBF). Spectroscopic data were acquired using a desktop (FOSS®) Vis-NIR spectroscopy ranging from 400 to 2500 nm of the electromagnetic spectrum. The spectral and reference data were submitted to principal component analysis (PCA) and partial least squares regression (PLSR) for the development of gluten adulteration detection models. Calibration models were constructed based on a full cross-validation approach, consisting of 51 samples for the calibration set and 21 samples for the test set. PCA scores plot discriminated gluten adulterated and unadulterated GBF samples with 100% accuracy for the first two principal components (PCs). The optimal prediction model was obtained after a combination of baseline (offset and baseline linear correlation) and standard normal variate (SNV) pre-processing technique. This model showed a 94% coefficient of determination of cross-validation (R2cv) and prediction (R2p); root mean square error of cross-validation (RMSECV) of 3.7 mg/kg, root mean square error of prediction (RMSEP) of 3.9 mg/kg; and RPD value of 4. This work has demonstrated that Vis-NIRS method is a robust and feasible technology that may be used to ensure the safety of banana flour and that this product stays gluten-free by providing good and reliable gluten detection and quantification prediction models.


Assuntos
Análise de Alimentos/métodos , Glutens/análise , Musa , Biomarcadores , Análise dos Mínimos Quadrados , Musa/química , Espectroscopia de Luz Próxima ao Infravermelho
19.
J Chromatogr A ; 1652: 462341, 2021 Aug 30.
Artigo em Inglês | MEDLINE | ID: mdl-34192611

RESUMO

We designed and synthesized three novel derivatization reagents bearing chiral 4-imidazolidinone, namely succinimidyl 2-(3-((benzyloxy)carbonyl)-1-methyl, ethyl, and -phenyl-5-oxoimidazolidin-4-yl)acetates (CIMs), for use in liquid chromatography-tandem mass spectrometry (LC-MS/MS) analysis. The CIMs were able to discriminate primary amines from other compounds such as secondary amines and phenols, based on their unique m/z reduction of precursor ion to form product ion in MS/MS. As amino acid derivatization reagents, the CIMs were compared in terms of enantioseparation of amino acid and detection sensitivity. CIMa-OSu with 1-methyl-5-oxoimidazolidinone moiety gave the best optical resolution and detection sensitivity among the CIM reagents. Next, we applied (R)-CIMa-OSu to determine amino acids in miso by LC-triple-quadrupole MS. The proposed method achieved simultaneous determination of 20 l-amino acids and two d-amino acids (d-alanine and d-serine) in the sample with a high sensitivity (limits of detection 5-238 fmol, signal-to-noise ratio 3.3). After derivatization with CIMa-OSu, it was possible to determine whether each peak in the chromatogram was a component of primary amine or not, by using a high-resolution orbitrap MS instrument.


Assuntos
Aminas , Aminoácidos , Cromatografia Líquida , Análise de Alimentos , Alimentos de Soja , Espectrometria de Massas em Tandem , Aminas/isolamento & purificação , Aminoácidos/isolamento & purificação , Cromatografia Líquida de Alta Pressão , Análise de Alimentos/métodos , Indicadores e Reagentes , Alimentos de Soja/análise , Estereoisomerismo
20.
Artigo em Inglês | MEDLINE | ID: mdl-34130205

RESUMO

Due to the strong background interferences in the low-mass region and poor reproducibility of conventional organic matrices, it is of great importance to develop a novel matrix for matrix-assisted laser desorption/ionization mass spectrometry (MALDI-MS) to qualitatively and quantitatively analyze small molecules. In this work, water-soluble fullerenol C60(OH)24-26 was selected as a MALDI matrix for the analysis of low-molecular-weight compounds in consideration of optical absorption property, water solubility and stability. Compared with the traditional matrices, fullerenol demonstrated lower background interference and stronger peak intensity. In addition, the hydrophilic fullerenol could avoid the heterogeneous crystallization in sample preparation, increase the reproducibility and sensitivity of MALDI-MS, and ameliorate quantitative analysis of small molecules. With saccharin as model analyte, quantitative analysis was carried out using fullerenol as matrix. The results demonstrated satisfying reproducibility and good tolerance to salt. The limit-of-detection of the quantitative analysis was as low as 4 pmol, and the linear range is 1-100 µg mL-1 with R2 greater than 0.99. The analytical results also showed excellent precision and accuracy, low matrix effect and good recovery rate. Fullerenol as a potential matrix was further validated in the quantification of saccharin sodium in different real food samples, such as nuts and drinks. This work not only confirms the potential of fullerenol for the quantitative analysis in food field, but also provides a new technique for rapid analysis of small molecules.


Assuntos
Análise de Alimentos/métodos , Fulerenos/química , Sacarina/análise , Espectrometria de Massas por Ionização e Dessorção a Laser Assistida por Matriz/métodos , Bebidas/análise , Limite de Detecção , Modelos Lineares , Nozes/química , Reprodutibilidade dos Testes
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