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1.
Zhongguo Zhong Yao Za Zhi ; 48(2): 356-365, 2023 Jan.
Artigo em Chinês | MEDLINE | ID: mdl-36725225

RESUMO

This research established a high-performance liquid chromatography(HPLC) method for simultaneous determination of isoorientin, orientin, vitexin, and isovitexin in Commelina communis to conduct content difference analysis and quality evaluation of 62 batches of C. communis from different origins. The HPLC content determination was performed on a Dikma Platisil ODS chromatographic column(4.6 mm×250 mm, 5 µm), with acetonitrile-0.1% formic acid(14∶86) as the mobile phase. The detection wavelength was set at 348 nm, the flow rate was 1.0 mL·min~(-1), and the column temperature was 35 ℃. The differences in origins and quality of 62 batches of C. communis were studied by chemometrics. The results showed that the determination of four components mani-fested a good linear relationship in the range of mass concentration(r>0.999 9), and the average recovery rate was 96.17%-103.0%. The relative standard deviations(RSDs) of precision, stability, and repeatability were all less than 2.0%. The content of four components from high to low was isoorientin>isovitexin>orientin>vitexin. Forty-seven batches of C. communis with clear origins were classified into six categories by chemometrics. C. communis from different origins had different qualities. Generally, C. communis from Western China, Central China, and South of China had superior qualities. The HPLC method established in this study is specific, simple, and efficient, which provides references for the comprehensive evaluation of the quality of C. communis. The chemometrics shows that the qualities of C. communis from different origins are largely different. Isoorientin can be used as an index to determine the content of C. communis, and its content limit should be set no less than 0.023%.


Assuntos
Commelina , Medicamentos de Ervas Chinesas , Quimiometria , Medicamentos de Ervas Chinesas/química , China , Cromatografia Líquida de Alta Pressão/métodos
2.
J Ethnopharmacol ; 305: 116093, 2023 Apr 06.
Artigo em Inglês | MEDLINE | ID: mdl-36603785

RESUMO

ETHNOPHARMACOLOGICAL RELEVANCE: Allergic contact dermatitis (ACD) is a common allergic inflammatory disease that is concomitant with skin swelling, redness, dry itching, and relapses. Prinsepia utilis Royle, a Chinese and Indian folk medicine, is rich in polyphenols with potential anti-inflammatory and skin-protective activities. However, the underlying mechanism of P. utilis leaf (PUL) in the treatment of ACD and its functional basis remains unclear. AIM OF THE STUDY: This study is aimed to explore and reveal the active substances and mechanism of PUL against ACD. MATERIALS AND METHODS: Hyaluronidase inhibitory assay and fluorescein isothiocyanate (FITC)-induced ACD mouse model were performed to assess the antiallergic effects of PUL in vitro and in vivo. Different solvents were applied to obtain multiple PUL extracts. The extracts were further tested for total phenolic content (TPC) and total flavonoid content (TFC) by using spectrophotometric assays. Polyphenolic profiles were analyzed by using ultrahigh-performance liquid chromatography coupled with time-of-flight mass spectrometry (UPLC-QTOF-MS/MS), and a simultaneous quantification method was established using UPLC-QTrap-MS/MS through multiple reaction monitoring (MRM) and applied to analyze the pharmacokinetics of the multiple major polyphenols of PUL in mice. RESULTS: The water extract of PUL with the highest TPC/TFC exhibited the strongest antihyaluronidase effect (IC50 = 231.93 µg/mL). In vivo assays indicated that the oral administration of PUL water extract dose-dependently attenuated ACD-like symptoms by decreased interleukin (IL)-4, IL-5, IL-13, IL-33, thymic stromal lymphopoietin, and IgE production, suppressed eosinophil and basophil secretion, and increasing the expression of tight junction (TJ) proteins (claudin-1 [CLDN-1] and occludin). Concomitantly, UPLC-QTOF-MS/MS analysis enabled the identification of 60 polyphenols and the pharmacokinetic parameters of seven quantified constituents of PUL were characterized. Four compounds, trans-p-coumaric acid 4-O-ß-D-glucopyranoside (11), vicenin-2 (21), isoschaftoside (31), and kaempferol 3-O-(2″,6″-di-O-α-L-rhamnopyransoyl)-ß-D-glucopyranoside (38) which displayed satisfactory pharmacokinetic features, were considered as potential effective substances in PUL. CONCLUSIONS: PUL water extract ameliorated the allergic inflammation of ACD by repairing the epithelial barrier and alleviating Th2-type allergic inflammation. The anti-allergic effect of PUL is closely related to its phenolic substances, and compounds 11, 21, 31, and 38 were the active substances of PUL. It revealed that P. utilis could be developed as a new source of antiallergic agents for ACD therapy.


Assuntos
Dermatite Alérgica de Contato , Medicamentos de Ervas Chinesas , Rosaceae , Camundongos , Animais , Espectrometria de Massas em Tandem , Quimiometria , Cromatografia Líquida , Dermatite Alérgica de Contato/tratamento farmacológico , Inflamação/tratamento farmacológico , Medicamentos de Ervas Chinesas/farmacologia , Flavonoides/farmacologia , Flavonoides/uso terapêutico , Extratos Vegetais/farmacologia , Extratos Vegetais/uso terapêutico
3.
Molecules ; 28(2)2023 Jan 12.
Artigo em Inglês | MEDLINE | ID: mdl-36677831

RESUMO

In this work, we employed EEM-PARAFAC (fluorescence excitation-emission matrices-parallel factor analysis) as a low-cost tool to study the oxidation pathways of (fluoro)quinolones. Amounts of 12.5 µM of enrofloxacin (ENR), ciprofloxacin (CIP), ofloxacin (OFL), oxolinic acid (OA), and flumequine (FLU), as individual solutions, were irradiated under UVA light. A 5-component PARAFAC model was obtained, four of them related to the parent pollutants, named as ENR-like (including CIP), OFL-like, OA-like, and FLU-like, and an additional one related to photoproducts, called ENRox-like (with an emission red-shift with respect to the ENR-like component). Mass spectrometry was employed to correlate the five PARAFAC components with their plausible molecular structures. Results indicated that photoproducts presenting: (i) hydroxylation or alkyl cleavages exhibited fingerprints analogous to those of the parent pollutants; (ii) defluorination and hydroxylation emitted within the ENRox-like region; (iii) the aforementioned changes plus piperazine ring cleavage emitted within the OA-like region. Afterwards, the five antibiotics were mixed in a single solution (each at a concentration of 0.25 µM) in seawater, PARAFAC being also able to deconvolute the fingerprint of humic-like substances. This approach could be a potential game changer in the analysis of (fluorescent) contaminants of emerging concern removals in complex matrices, giving rapid visual insights into the degradation pathways.


Assuntos
Quimiometria , Poluentes Químicos da Água , Fotólise , Espectrometria de Fluorescência/métodos , Fluoroquinolonas/química , Ciprofloxacina/química , Enrofloxacina/análise , Ofloxacino/análise , Espectrometria de Massas , Ácido Oxolínico , Poluentes Químicos da Água/química , Análise Fatorial , Substâncias Húmicas/análise
4.
Anal Methods ; 15(4): 502-511, 2023 Jan 26.
Artigo em Inglês | MEDLINE | ID: mdl-36617873

RESUMO

As a common fruit juice, grape juice is delicious and nutritious, making it very popular among consumers. However, some illegal manufacturers used shoddy products to lower costs and obtain high profits, which seriously threatens the health and interests of consumers. Hence, this paper proposed excitation-emission matrix (EEM) fluorescence spectroscopy combined with chemometric methods for the rapid identification and classification of commercial grape juices. Spectral characterization of different samples was achieved using the alternating trilinear decomposition (ATLD) algorithm, and chemically meaningful information was obtained and analyzed. Although both reconstituted and sweetened grape juices contain methyl anthranilate (MA) and 2'-aminoacetophenone (o-AAP), the content of MA in sweetened grape juice far exceeds that in reconstituted grape juice, and the MA in sweetened grape juice mainly comes from artificially added grape essence. Then two chemometric methods of hierarchical cluster analysis (HCA) and partial least squares discriminant analysis (PLS-DA) were used for the classification of reconstituted and sweetened grape juices. The results showed that the supervised classification model had a higher correct classification rate (CCR) than the unsupervised classification model, with PLS-DA obtaining 100% CCRs in both training and prediction sets. Therefore, the proposed strategy can be used as a powerful analytical method for the identification and classification of reconstituted and sweetened grape juices and provides a reliable scientific means for ensuring the authenticity and safety of the juice market.


Assuntos
Sucos de Frutas e Vegetais , Vitis , Vitis/química , Espectrometria de Fluorescência , Quimiometria , Frutas/química
5.
Molecules ; 28(1)2023 Jan 01.
Artigo em Inglês | MEDLINE | ID: mdl-36615530

RESUMO

Fourier-Transform mid-infrared (FTIR) spectroscopy offers a strong candidate screening tool for rapid, non-destructive and early detection of unauthorized virgin olive oil blends with other edible oils. Potential applications to the official anti-fraud control are supported by dozens of research articles with a "proof-of-concept" study approach through different chemometric workflows for comprehensive spectral analysis. It may also assist non-targeted authenticity testing, an emerging goal for modern food fraud inspection systems. Hence, FTIR-based methods need to be standardized and validated to be accepted by the olive industry and official regulators. Thus far, several literature reviews evaluated the competence of FTIR standalone or compared with other vibrational techniques only in view of the chemometric methodology, regardless of the inherent characteristics of the product spectra or the application scope. Regarding authenticity testing, every step of the methodology workflow, and not only the post-acquisition steps, need thorough validation. In this context, the present review investigates the progress in the research methodology on FTIR-based detection of virgin olive oil adulteration over a period of more than 25 years with the aim to capture the trends, identify gaps or misuses in the existing literature and highlight intriguing topics for future studies. An extensive search in Scopus, Web of Science and Google Scholar, combined with bibliometric analysis, helped to extract qualitative and quantitative information from publication sources. Our findings verified that intercomparison of literature results is often impossible; sampling design, FTIR spectral acquisition and performance evaluation are critical methodological issues that need more specific guidance and criteria for application to product authenticity testing.


Assuntos
Olea , Projetos de Pesquisa , Azeite de Oliva/análise , Espectroscopia de Infravermelho com Transformada de Fourier/métodos , Quimiometria , Óleos Vegetais/química , Contaminação de Alimentos/análise
6.
Anal Chim Acta ; 1239: 340710, 2023 Jan 25.
Artigo em Inglês | MEDLINE | ID: mdl-36628716

RESUMO

The new challenge in the investigation of cultural heritage is the possibility to obtain stratigraphical information about the distribution of the different organic and inorganic components without sampling. In this paper recently commercialized analytical set-up, which is able to co-register VNIR, SWIR, and XRF spectral data simultaneously, is exploited in combination with an innovative multivariate and multiblock high-throughput data processing for the analysis of multilayered paintings. The instrument allows to obtain elemental and molecular information from superficial to subsurface layers across the investigated area. The chemometric strategy proved to be highly efficient in data reduction and for the extraction and integration of the most useful information coming from the three different spectroscopies, also filling the gap between data acquisition and data understanding through the combination of principal component analysis (PCA), brushing, correlation diagrams and maps (within and between spectral blocks) on the low-level fused. In particular, correlation diagrams and maps provide useful information for the reconstruction of a stratigraphic structure without the need to take any sample, thanks to the effective account for inter-correlation among data (variables), which is able to effectively characterize the possible combinations of components located in the same depth level. The highly innovative technology and the data processing strategy are applied for the multi-level characterization of a complex painting reproduction as an illustrative pilot study.


Assuntos
Imageamento Hiperespectral , Pinturas , Projetos Piloto , Análise de Componente Principal , Quimiometria
7.
Anal Chim Acta ; 1239: 340694, 2023 Jan 25.
Artigo em Inglês | MEDLINE | ID: mdl-36628762

RESUMO

Quantitative analysis of spent nuclear fuel (SNF) is a very challenging task. High radioactivity, complex chemical composition and personnel safety requirements severely limit the number of analytical tools suitable for this problem. There is an urgent need for the methods that would provide for remote on-line quantification of elements in spent nuclear fuel and its reprocessing technological solutions. Here we propose a novel approach based on the registration of X-ray fluorescence radiation from SNF samples induced by fission products radioactivity. In this case the X-ray excitation conditions will obviously vary from sample to sample; moreover the resulting spectra will be a complex superposition of numerous signals from soft gamma emitters and X-ray fluorescence of various nature. These complex spectra can be effectively treated with chemometric data processing for quantification of particular elements. We have demonstrated the validity of this approach for direct analysis of U, Zr and Mo in SNF raffinate.


Assuntos
Resíduos Radioativos , Radioatividade , Resíduos Radioativos/análise , Quimiometria , Raios X , Raios gama
8.
Sensors (Basel) ; 23(2)2023 Jan 12.
Artigo em Inglês | MEDLINE | ID: mdl-36679682

RESUMO

Sensor arrays are currently attracting the interest of researchers due to their potential of overcoming the limitations of single sensors regarding selectivity, required by specific applications. Among the materials used to develop sensor arrays, graphene has not been so far extensively exploited, despite its remarkable sensing capability. Here we present the development of a graphene-based sensor array prepared by dropcasting nanostructure and nanocomposite graphene solution on interdigitated substrates, with the aim to investigate the capability of the array to discriminate several gases related to specific applications, including environmental monitoring, food quality tracking, and breathomics. This goal is achieved in two steps: at first the sensing properties of the array have been assessed through ammonia exposures, drawing the calibration curves, estimating the limit of detection, which has been found in the ppb range for all sensors, and investigating stability and sensitivity; then, after performing exposures to acetone, ethanol, 2-propanol, sodium hypochlorite, and water vapour, chemometric tools have been exploited to investigate the discrimination capability of the array, including principal component analysis (PCA), linear discriminant analysis (LDA), and Mahalanobis distance. PCA shows that the array was able to discriminate all the tested gases with an explained variance around 95%, while with an LDA approach the array can be trained to accurately recognize unknown gas contribution, with an accuracy higher than 94%.


Assuntos
Grafite , Nanocompostos , Amônia , Grafite/química , Quimiometria , Gases/análise
9.
Food Res Int ; 163: 112278, 2023 01.
Artigo em Inglês | MEDLINE | ID: mdl-36596188

RESUMO

The flavor and aroma quality of green tea are closely related to the harvest season. The aim of this study was to identify the harvesting season of green tea by alcohol/salt-based aqueous two-phase system (ATPS) combined with chemometric analysis. In this paper, the single factor experiments (SFM) and response surface methodology (RSM) optimization were designed to investigate and select the optimal ATPS. A total of 180 green tea samples were studied in this work, including 86 spring tea and 94 autumn tea. After the active components in green tea samples were extracted by the optimal ethanol/(NH4)2SO4 ATPS, the qualitative and quantitative analysis was realized based on HPLC-DAD combined with alternating trilinear decomposition-assisted multivariate curve resolution (ATLD-MCR) algorithm, with satisfactory spiked recoveries (86.00 %-112.45 %). The quantitative results obtained from ATLD-MCR model were subjected to chemometric pattern recognition analysis. The constructed partial least squares-discriminant analysis (PLS-DA) and orthogonal partial least squares-discriminant analysis (OPLS-DA) models showed better results than the principal component analysis (PCA) model, and the R2Xcum values (>0.835) and R2Ycum (>0.937) were close to 1, the Q2cum values were greater than 0.75 (>0.933), and the differences between R2Ycum and Q2cum were not larger than 0.2, indicating excellent cross-validation prediction performance of the models. Furthermore, the classification results based on the hierarchical clustering analysis (HCA) were consistent with the PCA, PLS-DA and OPLS-DA results, establishing a good correlation between tea active components and the harvesting seasons of green tea. Overall, the combination of ATPS and chemometric methods is accurate, sensitive, fast and reliable for the qualitative and quantitative determination of tea active components, providing guidance for the quality control of green tea.


Assuntos
Quimiometria , Chá , Estações do Ano , Análise Discriminante , Etanol , Cloreto de Sódio , Cloreto de Sódio na Dieta
10.
Anal Methods ; 15(4): 455-461, 2023 Jan 26.
Artigo em Inglês | MEDLINE | ID: mdl-36602089

RESUMO

As goat milk has a higher economic value compared to cow milk, the phenomenon of adulterating goat milk with cow milk appears in the market. In this study, the potential of Raman spectroscopy along with chemometrics was investigated for the authentication and quantitation of liquid goat milk adulterated with cow milk. First, the results of principal component analysis (PCA) showed that there were differences between the Raman spectra of cow and goat milk, which made quantitative experiments possible. For quantification, three different brands of cow milk and goat milk were selected randomly and adulterated goat milk with cow milk at the proportion of 5-95%. 342 samples were used for the construction of the partial least squares regression (PLSR) model with 80% for the calibration set and 20% for the prediction set. The PLSR model showed excellent performance in quantifying the level of adulteration, for the prediction set, with a coefficient of determination (R2) of 0.9781, root mean square error (RMSE) of 3.82%, and a ratio of prediction to deviation (RPD) of 6.8. The results demonstrated the potential of Raman spectroscopy as a rapid, low cost and non-destructive analytical tool for detecting adulteration in goat milk.


Assuntos
Quimiometria , Leite , Animais , Bovinos , Feminino , Leite/química , Análise Espectral Raman , Contaminação de Alimentos/análise , Cabras
12.
Environ Res ; 216(Pt 3): 114632, 2023 01 01.
Artigo em Inglês | MEDLINE | ID: mdl-36347397

RESUMO

The ubiquitous distribution of plastics and microplastics (MPs) and their resistance to biological and chemical decay is adversely affecting the environment. MPs are considered as emerging contaminants of concern in all the compartments, including terrestrial, aquatic, and atmospheric environments. Efficient monitoring, detection, and removal technologies require reliable methods for a qualitative and quantitative analysis of MPs, considering point-of-need testing a new evolution and a great trend at the market level. In the last years, portable spectrometers have gained popularity thanks to the excellent capability for fast and on-site measurements. Ultra-compact spectrometers coupled with chemometric tools have shown great potential in the polymer analysis, showing promising applications in the environmental field. Nevertheless, systematic studies are still required, in particular for the identification and quantification of fragments at the microscale. This study demonstrates the proof-of-concept of a Miniaturized Near-Infrared (MicroNIR) spectrometer coupled with chemometrics for the quantitative analysis of ternary mixtures of MPs. Polymers were chosen representing the three most common polymers found in the environment (polypropylene, polyethene, and polystyrene). Daily used plastic items were mechanically fragmented at laboratory scale mimicking the environmental breakdown process and creating "true-to-life" MPs for the assessment of analytical methods for MPs identification and quantification. The chemical nature of samples before and after fragmentation was checked by Raman spectroscopy. Sixty three different mixtures were prepared: 42 for the training set and 21 for the test set. Blends were investigated by the MicroNIR spectrometer, and the dataset was analysed using Principal Component Analysis (PCA) and Partial Least Square (PLS) Regression. PCA score plot showed a samples distribution consistent with their composition. Quantitative analysis by PLS showed the great capability prediction of the polymer's percentage in the mixtures, with R2 greater than 0.9 for the three analytes and a low and comparable Root-Mean Square Error. In addition, the developed model was challenged with environmental weathered materials to validate the system with real plastic pollution. The findings show the feasibility of employing a portable tool in conjunction with chemometrics to quantify the most abundant forms of MPs found in the environment.


Assuntos
Microplásticos , Plásticos , Plásticos/análise , Quimiometria , Espectroscopia de Luz Próxima ao Infravermelho/métodos , Análise dos Mínimos Quadrados
13.
Spectrochim Acta A Mol Biomol Spectrosc ; 288: 122186, 2023 Mar 05.
Artigo em Inglês | MEDLINE | ID: mdl-36481535

RESUMO

Traumatic lung injury (TLI), which is a common mechanical injury, is receiving increasing attention because of its serious hazards. In forensic practices, accurately identifying TLI is of great importance for investigations and case trials. The main goal of this research was to identify TLI utilizing attenuated total reflection-Fourier transform infrared (ATR-FTIR) spectroscopy in combination with chemometrics. The macroscopic appearance of lung tissue showed that identifying TLI in lung tissue at the decomposition stage is not feasible by only visualization, and significant pulmonary hypostasis was observed in the lungs regardless of whether the lung tissue was injured. Average spectra and principal component analysis (PCA) suggested that the biochemical difference between injured lung tissue samples from the TLI group and noninjured lung tissue samples from the negative control group was mainly attributed to the different structures and contents of proteins. Partial least squares discriminant analysis (PLS-DA) was then utilized to identify TLI with an accuracy of 96.4% and 98.6% based on the training set and the test set, respectively. Next, we focused on samples that were misclassified in the model and proposed that the misclassification could be caused by the pulmonary hypostasis effect. Therefore, two additional PCA and PLS-DA models were created to identify the pulmonary hypostatic areas between the TLI group and the negative control group and the nonpulmonary hypostatic areas between the TLI group and the negative control group. The PCA results indicated that the biochemical difference between the two groups was still associated with proteins, and the two PLS-DA models achieved 100% accuracy based on both the training and test sets. This result indicated that when pulmonary hypostasis was considered and the lung tissue was divided into pulmonary hypostatic areas and nonpulmonary hypostatic areas for separate comparisons, TLI identification was achieved with a greater accuracy than that obtained when the two areas were combined. This research confirms that the combined application of ATR-FTIR spectroscopy and chemometrics can be utilized to accurately identify TLI.


Assuntos
Lesão Pulmonar , Humanos , Lesão Pulmonar/diagnóstico , Espectroscopia de Infravermelho com Transformada de Fourier/métodos , Quimiometria , Análise Discriminante , Análise dos Mínimos Quadrados , Análise de Componente Principal , Pulmão , Proteínas Mutadas de Ataxia Telangiectasia
14.
Food Chem ; 407: 135116, 2023 May 01.
Artigo em Inglês | MEDLINE | ID: mdl-36493480

RESUMO

As a popular vegetable, the unique and pleasant aroma is the key quality characteristic of Toona sinensis. To explore the sources and differences of aroma, the volatilomic profiling in the leaves and shoots of seven T. sinensis cultivars were investigated by chemometric analysis. The results indicated that aroma differences of each cultivar can be distinguished by W5S, W1S, W1W and W2S sensors during E-nose analysis. More than two thirds of all volatile organic compounds (VOCs) were derived from the leaves of most cultivars, except for Ximu toon. Notably, 2-mercapto-3,4-dimethyl-2,3-dihydrothiophene, 3,4-dimethyl thiophene, methyl thiirane, isocaryophyllene and hexanal were the major VOCs in both the leaves and shoots of T. sinensis. By constructing a weighted correlation network model, 5 modules and 11 hub VOCs were identified in the leaf samples of all cultivars. The data indicate that differential intracellular metabolic responses are responsible for the aroma formation of seven T. sinensis cultivars.


Assuntos
Odorantes , Compostos Orgânicos Voláteis , Odorantes/análise , Toona , Quimiometria , Compostos Orgânicos Voláteis/análise , Folhas de Planta/química
15.
Food Chem ; 407: 135123, 2023 May 01.
Artigo em Inglês | MEDLINE | ID: mdl-36493482

RESUMO

The metabolic composition of thyme, one of the most used aromatic herbs, is influenced by environmental and post-harvest processing factors, presenting the possibility of exploiting thyme fingerprint to assess its authenticity. In this study, a comprehensive UHPLC-QTOF-HRMS fingerprinting approach was applied with a dual objective: (1) tracing thyme from three regions of production (Spain, Morocco, and Poland) and (2) evaluating the metabolic differences in response to processing, considering sterilized thyme samples. Multivariate statistics reveal 37 and 33 key origin and processing differentiation compounds, respectively. The findings highlighted the remarkable "terroir" influence on thyme fingerprint, noticing flavonoids, amino acids, and peptides among the most discriminant chemical classes. Thyme sterilization led to an overall metabolite enrichment, most likely due to the facilitated compound accessibility as a result of processing. The findings provide a comprehensive metabolomics insight into the origin and processing effect on thyme composition for product traceability and quality assessment.


Assuntos
Thymus (Planta) , Análise Discriminante , Cromatografia Líquida de Alta Pressão , Quimiometria , Metabolômica
16.
Food Chem ; 407: 135173, 2023 May 01.
Artigo em Inglês | MEDLINE | ID: mdl-36527949

RESUMO

Metabolite profiles of normal and defective dry, firm and dark (DFD) meat extracts with known ultimate pH (pHu) values were determined by Orbitrap Tribrid ID-X untargeted analysis coupled to chemometrics. An intelligent MS3 AcquireXTM workflow firstly approached the unambiguous characterization of detected features that were subsequently quantified by a complementary MS1 study of biological replicates. Chemometric research revealed how threonylphenylalanine (overexpressed in normal meats) together to tetradecadienoyl- and hydroxydodecanoyl-carnitines (both overexpressed in DFD meats) appropriately grouped meat groups assayed. Robustness of such biomarkers was confirmed through a time-delayed study of a blind set of samples (unknown pHu) and evidenced limitations of pHu as an isolated parameter for accurate meat quality differentiation. Other acyl-carnitines also characterized DFD samples, suggesting interferences induced by pre-slaughter stress (PSS) on lipid catabolism that would explain accumulation of such intermediate metabolites. Results achieved can ease understanding of biochemical mechanisms underlying meat quality defects.


Assuntos
Quimiometria , Carne , Carne/análise , Biomarcadores , Concentração de Íons de Hidrogênio , Metabolômica
17.
Spectrochim Acta A Mol Biomol Spectrosc ; 285: 121883, 2023 Jan 15.
Artigo em Inglês | MEDLINE | ID: mdl-36126622

RESUMO

Alternative routes such as virus transmission or cross-contamination by food have been suggested, due to reported cases of SARS-CoV-2 in frozen chicken wings and fish or seafood. Delay in routine testing due to the dependence on the PCR technique as the standard method leads to greater virus dissemination. Therefore, alternative detection methods such as FTIR spectroscopy emerge as an option. Here, we demonstrate a fast (3 min), simple and reagent-free methodology using attenuated total reflection-Fourier transform infrared (ATR-FTIR) spectroscopy for discrimination of food (chicken, beef and fish) contaminated with the SARS-CoV-2 virus. From the IR spectra of the samples, the "bio-fingerprint" (800 - 1900 cm-1) was selected to investigate the distinctions caused by the virus contamination. Exploratory analysis of the spectra, using Principal Component of Analysis (PCA), indicated the differentiation in the data due to the presence of single bands, marked as contamination from nucleic acids including viral RNA. Furthermore, the partial least squares discriminant analysis (PLS-DA) classification model allowed for discrimination of each matrix in its pure form and its contaminated counterpart with sensitivity, specificity and accuracy of 100 %. Therefore, this study indicates that the use of ATR-FTIR can offer a fast and low cost and not require chemical reagents and with minimal sample preparation to detect the SARS-CoV-2 virus in food matrices, ensuring food safety and non-dissemination by consumers.


Assuntos
COVID-19 , SARS-CoV-2 , Bovinos , Animais , Espectroscopia de Infravermelho com Transformada de Fourier/métodos , Quimiometria , COVID-19/diagnóstico , Análise Discriminante , Análise dos Mínimos Quadrados , Peixes
18.
Ultrason Sonochem ; 92: 106268, 2023 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-36543045

RESUMO

The enzymatic browning induced in amla juice due to the high activity of polyphenol oxidase (PPO) and peroxidase (POD) is one of the critical issues faced by the industry. The present study assessed the suitability of non-thermal, high-intensity ultrasound (US) on the inactivation of PPO and POD in fresh Indian Gooseberry juice. Ultrasonic waves, using a 6 mm titanium alloy probe were irradiated in the juice at a maximum power of 455 W and frequency of 20 kHz. The subsequent effects on biochemical attributes were studied using response surface methodology. Inactivation rates of 90.72 % and 73.18 %, respectively, for PPO and POD enzymes, were observed at the highest US intensity and exposure time. Numerical optimisation using the three-factor, three-level Box-Behnken design suggested that an optimum process at 70 % (energy density: 1610 Wcm-2) pulsed at 5 s on and 5 s off for 7 min 30 s resulted in PPO and POD inactivation of the order of 76.42 % and 64.57 % respectively. At these experimental conditions, the optimized levels of biochemical attributes i.e., ascorbic acid (738.50 mg/100 mL), total phenols (17.10 mg/mL), DPPH antioxidant activity (58.47 %), tannins (7.11 µg/mL), colour change (ΔE = 9.04) and flavonoids (6.14 mg/mL) were achieved. The overall statistical models were significant for all the responses except for reducing sugars. Furthermore, the approximation equations for individual responses indicated that the goodness of fit was adequate (R2 > 0.90). The results suggested that ultrasound is a suitable processing technique for amla juice stabilisation compared to thermal treatments that result in the loss of quality.


Assuntos
Phyllanthus emblica , Quimiometria , Antioxidantes/farmacologia , Ácido Ascórbico , Manipulação de Alimentos/métodos , Peroxidase , Peroxidases , Catecol Oxidase
19.
Spectrochim Acta A Mol Biomol Spectrosc ; 289: 122215, 2023 Mar 15.
Artigo em Inglês | MEDLINE | ID: mdl-36508903

RESUMO

OBJECTIVE: To establish a method for quality evaluation of the fruit of Crataegus pinnatifida Bunge, also known as Shanzha, by near-infrared spectroscopy combined with chemometrics. METHOD: Seventy-two batches of Shanzha samples were collected, and the content of total components (flavonoids, phenols and organic acids), monomer components (chlorogenic acid, hyperoside and isoquercitrin), as well as the antioxidant activity of 60% ethanol extract were determined by usual methods. Then, all measured values were correlated with the near infrared spectra of Shanzha, and the partial least squares regression models were established. As to improve the model performance, various methods for spectra pretreatment and wavelength selection were investigated. RESULTS: After optimization, the models obtained the coefficients of determination in both calibration and prediction >0.9, and the residual prediction deviations >3, indicating that the models had good prediction abilities. CONCLUSION: The present method can serve as an alternative to the methods for comprehensive and rapid quality evaluation of Shanzha.


Assuntos
Antioxidantes , Crataegus , Antioxidantes/farmacologia , Antioxidantes/análise , Crataegus/química , Espectroscopia de Luz Próxima ao Infravermelho/métodos , Frutas/química , Quimiometria , Análise dos Mínimos Quadrados
20.
Spectrochim Acta A Mol Biomol Spectrosc ; 289: 122226, 2023 Mar 15.
Artigo em Inglês | MEDLINE | ID: mdl-36512964

RESUMO

Cinnamon is a valuable aromatic spice widely used in pharmaceutical and food industry. Commonly, two-cinnamon species are available in the market, Cinnamomum verum (true cinnamon), cropped only in Sri Lanka, and Cinnamomum cassia (false cinnamon), cropped in different geographical origins. Thus, this work aimed to develop classification models based on NIR-hyperspectral imaging (NIR-HSI) coupled to chemometrics to classify C. verum and C. cassia sticks. First, principal component analysis (PCA) was applied to explore hyperspectral images. Scores surface displayed the high similarity between species supported by comparable macronutrient concentration. PC3 allowed better class differentiation compared to PC1 and PC2, with loadings exhibiting peaks related to phenolics/aromatics compounds, such as coumarin (C. cassia) or catechin (C. verum). Partial least square discriminant analysis (PLS-DA) and Support vector machine (SVM) reached similar performance to classify samples according to origin, with error = 3.3 % and accuracy = 96.7 %. A permutation test with p < 0.05 validated PLS-DA predictions have real spectral data dependency, and they are not result of chance. Pixel-wise (approach A) and sample-wise (approach B, C and D) classification maps reached a correct classification rate (CCR) of 98.3 % for C. verum and 100 % for C. cassia. NIR-HSI supported by classification chemometrics tools can be used as reliable analytical method for cinnamon authentication.


Assuntos
Quimiometria , Cinnamomum zeylanicum , Imageamento Hiperespectral , Análise Discriminante , Análise de Componente Principal , Análise dos Mínimos Quadrados , Máquina de Vetores de Suporte
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