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1.
Chem Biodivers ; : e202400670, 2024 May 15.
Artículo en Inglés | MEDLINE | ID: mdl-38747034

RESUMEN

Cancer remains a significant global health concern, with mortality rates steadily rising and prompting an urgent search for effective treatments. This study focuses on the medicinal properties of plants from the Phyllanthus genus, specifically Phyllanthus amarus and Phyllanthus niruri, which have shown promise in traditional medicine. Through bioguided fractionation using preparative high-performance liquid chromatography (HPLC), bioactive compounds were isolated and identified using ultra-performance liquid chromatography coupled to time-of-flight mass spectrometry (UHPLC-QTOF-MSE) and nuclear magnetic resonance (NMR) spectroscopy. Chemometric analyses such as principal component analysis (PCA) aided in understanding metabolite distribution. Biological assays demonstrated cytotoxic activities of specific fractions against cancer cell lines, notably the PhyN 4n fraction from P. niruri, which induced S-phase cell cycle arrest and apoptosis in HL60 cells. These findings underscore the anticancer potential of Phyllanthus species and lay the groundwork for future drug development efforts. The study's integration of advanced analytical techniques, chemometrics, and biological assays provides valuable insights for harnessing natural products in the fight against cancer.

2.
J Chem Ecol ; 48(7-8): 660-669, 2022 Aug.
Artículo en Inglés | MEDLINE | ID: mdl-35653012

RESUMEN

In most commercial pine farms in southern Brazil, black capuchin causes damage to wood and financial losses when it removes bark from some pine species to feed upon underlying vascular tissues. Therefore, this study aimed to evaluate the variability of the primary metabolites of phloem saps from 10 different species of pine by NMR spectroscopy, as well as the aroma compounds using SPME-GC-MS. Each technique provided a different set of metabolites that we can correlate to monkey predilection. The PCA showed monosaccharide (detected by NMR) and α-pinene (pine-like and resinous flavor descriptors) as attractive compounds for monkeys. On the other hand, the low content of monosaccharide and the high content of ß-phellandrene (citrus odor descriptor) was observed in less attacked pine species (P. patula). The data fusion on primary metabolites and aroma compounds corroborated the individual analyses, complementing the comprehension of the monkey predilection. Thus, P. elliottii was an avoided tree even with high content of sugars possibly due to its high content of ß-phellandrene (citrus odor). The results are useful for further behavioral studies to determine the role that each highlighted metabolite plays in chemically mediated animal-plant interactions.


Asunto(s)
Citrus , Pinus , Animales , Citrus/metabolismo , Cromatografía de Gases y Espectrometría de Masas , Monosacáridos/metabolismo , Floema/metabolismo , Pinus/química , Sapajus
3.
J Chem Inf Model ; 61(6): 2516-2522, 2021 06 28.
Artículo en Inglés | MEDLINE | ID: mdl-34014674

RESUMEN

Natural products and their secondary metabolites are promising starting points for the development of drug prototypes and new drugs, as many current treatments for numerous diseases are directly or indirectly related to such compounds. State-of-the-art, curated, integrated, and frequently updated databases of secondary metabolites are thus highly relevant to drug discovery. The SistematX Web Portal, introduced in 2018, is undergoing development to address this need and documents crucial information about plant secondary metabolites, including the exact location of the species from which the compounds were isolated. SistematX also allows registered users to log in to the data management area and gain access to administrative pages. This study reports recent updates and modifications to the SistematX Web Portal, including a batch download option, the generation and visualization of 1H and 13C nuclear magnetic resonance spectra, and the calculation of physicochemical (drug-like and lead-like) properties and biological activity profiles. The SistematX Web Portal is freely available at http://sistematx.ufpb.br.


Asunto(s)
Productos Biológicos , Bases de Datos Factuales , Descubrimiento de Drogas , Espectroscopía de Resonancia Magnética , Plantas
4.
Chem Biodivers ; 16(6): e1900050, 2019 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-30980460

RESUMEN

The development of studies on emissions of volatile organic compounds (VOCs) by inflorescence of oil palms deserves a special attention regarding the importance to reproduction success and for increase of production. This study aimed to evaluate metabolic profiling of VOCs expelled by male and female inflorescences of different oil palm species (African oil palm, Amazonian Caiaué and the interspecific hybrid BRS-Manicoré), associating the composition variability with main pollinators to improve the comprehension of the plant-insect relationship. The phenylpropanoids, terpenoids and the aliphatic hydrocarbons were predominant classes detected in inflorescences of oil palms and the major compound was estragole. This result may be correlated with attraction of Elaidobius pollinators, since these insects were not attracted by Caiaué, which emitted estragole only in trace amounts. However, Caiaué and the hybrid species were visited by other native species whose frequencies were low and their success as pollinators could not be expected.


Asunto(s)
Aceite de Palma/química , Compuestos Orgánicos Volátiles/química , Animales , Arecaceae/química , Arecaceae/metabolismo , Conducta Animal/efectos de los fármacos , Análisis por Conglomerados , Femenino , Cromatografía de Gases y Espectrometría de Masas , Hidrocarburos/química , Hidrocarburos/farmacología , Masculino , Aceite de Palma/metabolismo , Polinización , Terpenos/química , Terpenos/farmacología , Compuestos Orgánicos Volátiles/metabolismo , Compuestos Orgánicos Volátiles/farmacología , Gorgojos/fisiología
5.
Analyst ; 139(6): 1350-4, 2014 Mar 21.
Artículo en Inglés | MEDLINE | ID: mdl-24503630

RESUMEN

Polysaccharide-based chiral stationary phases (CSP) demonstrate great versatility and higher chiral selectivity for a variety of chiral compounds in multimodal elution modes (normal, reverse and polar organic). The main role of CSP phenyl carbamate based derivatives as chiral selectors is the formation of diastereoisomeric complexes by means of π-π interaction, dipole-dipole, hydrogen bonding and/or inclusion complex mechanisms. Nevertheless, the mechanism behind their enantioselectivity requires clarification. High resolution magic angle spinning nuclear magnetic resonance spectroscopy ((1)H HR/MAS NMR) has provided key information on the recognition process at the binding sites of the CSP surface. Herein we report the results obtained using omeprazole as a probe for these investigations.


Asunto(s)
Amilosa/química , Antiulcerosos/química , Espectroscopía de Resonancia Magnética/métodos , Omeprazol/química , Estereoisomerismo
6.
Foods ; 11(11)2022 Jun 03.
Artículo en Inglés | MEDLINE | ID: mdl-35681401

RESUMEN

Cassava is an important staple food for low-income countries. However, its cooking characteristics are especially affected by genotype. In this study, two groups of genotypes, namely hard to cook (HTC) and easy to cook (ETC), were harvested at different times (9 and 15 months), and evaluated by NMR coupled to chemometrics. Additionally, lignin of these materials was studied by 1H-13C HSQC NMR. The carbohydrates were the most important class of compounds to differentiate the cassava genotypes. The correlation of NMR with cooking time and starch content showed that the higher content of primary metabolites, mostly glucose, can be associated with longer cooking times and reduction of starch, corroborating the metabolic pathways analysis. Furthermore, it was observed that the lignin from cell walls did not differentiate the cooking performance of the genotypes.

7.
Food Chem ; 382: 132359, 2022 Jul 15.
Artículo en Inglés | MEDLINE | ID: mdl-35152022

RESUMEN

Touriga Nacional is a well-adapted Portuguese grape variety in São Francisco River Valley (northeastern Brazil). Nevertheless, it has only been indicated to short-term consumption because of the lack of chemical stability, which is attributed to low grape acidity and incomplete phenolic maturity. Therefore, we used Ultra-Performance Liquid Chromatography coupled High-resolution Mass Spectrometry, Nuclear Magnetic Resonance and chemometrics (PCA and PLS-DA) to evaluate the grape maturity and maceration time on chemical composition of wines from two harvest seasons. Moreover, we investigated how these experimental factors could affect their chemical stability. Grapes maturity showed to be the main effect. Overall, phenolic acids and short-chain organic acids were found to be at higher levels in wines produced with unripe grapes from February and shorter maceration time (p < 0.05). Proanthocyanidins and other flavonoids were increased in wines macerated for longer time using overripe grapes harvested in July. Furthermore, stable wines were made from overripe grapes, which contained more galacturonic acid.


Asunto(s)
Vitis , Vino , Frutas/química , Espectroscopía de Resonancia Magnética , Espectroscopía de Protones por Resonancia Magnética , Vitis/química , Vino/análisis
8.
Food Res Int ; 136: 109506, 2020 10.
Artículo en Inglés | MEDLINE | ID: mdl-32846584

RESUMEN

This study evaluated the effects of High-Temperature Short Time (HTST), Ultra High Temperature (UHT), and the non-thermal processes High Power Ultrasound (US), UV-pulsed-light and Low Pressure Plasma (LPP) on the composition, stability, and bioactive compounds bioaccessibility of açai juice. 1H NMR based approach, coupled to chemometrics, was applied to evaluate the changes in the juice composition. All the non-thermal processes increased the sugars content (glucose and fructose), and the amino acid betaine, except the combined processing of ultrasound followed by low-pressure plasma (US.LPP). HTST and UHT increased the fatty acids and phenolic compounds content in the açai juice. The bioaccessibility of phenolic compounds decreased due to the processing. After thermal sterilization (UHT), the anthocyanin bioaccessibility was 2-fold higher. The combined non-thermal treatment reduced the biocompounds bioaccessibility to 40% of the non-processed juice. However, the combined US.LPP improved the bioaccessibility of vitamin C by 8%. UHT increased the anthocyanin's bioaccessibility but sharply decreased vitamin C bioaccessibility. Higher impact of thermal processing on vitamin C, anthocyanins, total phenolics, PPO, POD, DPPH, ABTS, and FRAP was verified after 45 and 60 days of storage compared to the non-thermally processed samples.


Asunto(s)
Antocianinas , Manipulación de Alimentos , Antocianinas/análisis , Frutas/química , Calor , Fenoles/análisis
9.
Food Chem ; 324: 126874, 2020 Sep 15.
Artículo en Inglés | MEDLINE | ID: mdl-32353658

RESUMEN

Thermally-processed coconut water often develop a commercially-undesirable pink color, thus, NMR, UPLC-HRMS, GC-MS analyses combined with chemometrics approach were applied to evaluate chemical variations in comparison to tender water (control) that could explain such color change. Chemometrics on negative ionization mode dataset showed trimeric and A-type dimeric procyanidins, and caffeoylshikimic acid as main identified secondary metabolites induced by processing, while, control water presented mainly cytokinin trans-zeatin riboside, procyanidin dimer, caffeoylshikimic acid and trihydroxy-octadecenoic acid. Processing increased long-chain saturated palmitic and stearic fatty acids contents, meanwhile NMR analysis showed a decline in primary metabolites content as sugars fructose and glucose, and short-chain organic acids. Among the results observed for thermally processed coconut water, the increase in oligomeric procyanidins as A-type dimer and trimer may be associated with pink color development as these are precursors of anthocyanin pigment and/or by enhancing color stability of anthocyanin solutions.


Asunto(s)
Cromatografía Líquida de Alta Presión , Cocos/química , Cromatografía de Gases y Espectrometría de Masas , Espectroscopía de Resonancia Magnética , Espectrometría de Masas , Antocianinas/análisis , Antocianinas/aislamiento & purificación , Cocos/metabolismo , Color , Citocininas/análisis , Citocininas/aislamiento & purificación , Fructosa/análisis , Fructosa/aislamiento & purificación , Análisis de Componente Principal , Proantocianidinas/análisis , Proantocianidinas/aislamiento & purificación , Extracción en Fase Sólida , Temperatura
10.
Food Res Int ; 131: 109000, 2020 05.
Artículo en Inglés | MEDLINE | ID: mdl-32247458

RESUMEN

In this study, the effect of plasma and ozone processing on the quality of coconut water was evaluated. For ozone processing, the samples were submitted to different ozone loads and temperatures. For atmospheric cold plasma processing (ACP), samples were exposed to plasma under different frequencies and voltages. The coconut water pH, soluble solids, titratable acidity, color, total phenolic content, and enzymatic activity were determined before and after treatments. The main compounds were also determined by NMR spectroscopy and chemometric analysis. Both processes did not change the pH values, total soluble solids, titratable acidity, and color. Chemometrics analysis of 1H NMR dataset showed no relevant changes after the processing. All ozone treatments promoted complete inactivation of POD activity and did not affect the content of phenolic compounds. After ACP, the smallest POD residual activity was observed when higher frequencies were applied, and slight changes in phenolic compounds content were observed.


Asunto(s)
Cocos , Manipulación de Alimentos/métodos , Ozono , Gases em Plasma , Cromatografía Liquida/métodos , Frutas/química , Espectroscopía de Resonancia Magnética , Espectrometría de Masas/métodos , Agua/análisis
11.
Food Chem ; 309: 125761, 2020 Mar 30.
Artículo en Inglés | MEDLINE | ID: mdl-31757490

RESUMEN

Innovative chemometric approaches by NMR and LC-MS data fusion (multiblock analysis) and decomposition of the GC-MS raw data by PARADISe were applied to evaluate the influence of thermal and non-thermal processing on the composition of cashew apple juices. Comparative investigations by Principal Component Analysis (PCA) highlighted pronounced effect of thermal processing on juice compared to non-thermal processing, as decreases of anacardic acids, sucrose, malic acid, tyrosine, phenylalanine, and important flavor compounds (esters, aldehydes, and ketones). Ultrasound presented relevant influence on increase of anacardic acids concentration. Non-thermal processing carried out at more intense conditions (10 min of ultrasound, 5 min of ozone, and pulsed light at 10 V) showed pronounced effect compared to other non-thermal processing. Although individual PCA enables to detect the influence of different processing technologies, data fusion and PARADISe presented advantages, since a more comprehensive understanding of the relationship among chemical changes from different analytical techniques were established.


Asunto(s)
Anacardium/química , Jugos de Frutas y Vegetales/análisis , Ácidos Anacárdicos/análisis , Anacardium/metabolismo , Cromatografía Líquida de Alta Presión , Cromatografía de Gases y Espectrometría de Masas , Calor , Espectroscopía de Resonancia Magnética , Malatos/análisis , Ozono/química , Análisis de Componente Principal , Sonicación , Espectrometría de Masas en Tándem , Rayos Ultravioleta
12.
Food Res Int ; 138(Pt A): 109759, 2020 12.
Artículo en Inglés | MEDLINE | ID: mdl-33292941

RESUMEN

Egletes viscosa is a Brazilian medicinal herb consumed as flower bud tea due to its gastroprotective properties. This plant possesses two essential oil-based chemical varieties: trans-pinocarveyl acetate-rich chemotype A and cis-isopinocarveyl acetate- rich chemotype B. Therefore, we developed two simple, fast and reliable methods for discrimination of E. viscosa chemotypes using NIR and 1H qNMR spectroscopies combined with the chemometrics tools (iPLS and PLS-DA). Both methods showed high sensitivity, precision and specificity in the cross-validation tests. The NIR method has the advantages of being non-destructive and analyzable by portable devices, enabling its application for field and industrial evaluations. Meanwhile, the 1H qNMR method allows the quantification of the bioactive components ternatin, tanabalin, and centipedic acid. These aforementioned compounds were found higher in the chemotype A. Accordingly, our methods showed to be complimentary approaches for authenticity and/or quality control of E. viscosa-derived raw materials and herbal products.


Asunto(s)
Asteraceae , Aceites Volátiles , Plantas Medicinales , Brasil , Extractos Vegetales
13.
Food Res Int ; 125: 108621, 2019 11.
Artículo en Inglés | MEDLINE | ID: mdl-31554108

RESUMEN

The study investigated the influence of atmospheric plasma processing on cashew nut composition as well as on its allergenicity. The cashew nuts were processed by low-pressure plasma, using glow discharge plasma (80 W and 50 kHz power supply). Anacardic acids and allergens were quantified by HPLC and immunoassay, respectively. Additionally, the overall composition was evaluated by 1H qNMR. Increases in amounts of anacardic acids (15:1, 15:2, and 15:3) and fatty acids (oleic, linoleic, palmitic and stearic) were detected after all process conditions, with 70.92% of total variance captured using 2 LVs. The total amount of anacardic acids increased from 0.7 to 1.2 µg·mg-1 of nut. The major change was observed for anacardic acid (C15:3) with an increase from 0.2 to 0.55 µg/mg of nut for the samples treated with a flow of 10 mL·min-1 and 30 min of processing. On the other hand, the amount of sucrose decreased, from 33 to 18 mg·g-1 of nut, after all processing conditions. Plasma processing of cashew nuts did not affect binding of either the rabbit anti-cashew or human cashew allergic IgE binding. Among the treatments, 10 min of plasma processing at flow rate of 30 mL·min-1 of synthetic air followed by 20 min at flow rate 5.8 mL·min-1 had the least effect on nut composition as a whole.


Asunto(s)
Anacardium , Manipulación de Alimentos/métodos , Irradiación de Alimentos/métodos , Nueces/química , Nueces/inmunología , Alérgenos/análisis , Ácidos Anacárdicos/análisis , Animales , Ácidos Grasos/análisis , Humanos , Inmunoglobulina E/metabolismo , Microscopía Electrónica de Rastreo , Hipersensibilidad a la Nuez/prevención & control , Extractos Vegetales/inmunología , Conejos
14.
Food Chem ; 289: 558-567, 2019 Aug 15.
Artículo en Inglés | MEDLINE | ID: mdl-30955648

RESUMEN

São Francisco River Valley (SFRV) is a wine-producing semi-arid region in Brazil. Therefore, we used a 1H NMR and UPLC-MS-based metabolomic approach coupled to chemometrics to evaluate the variability in Chenin Blanc and Syrah wines for two harvest seasons, two vine training system and six rootstocks. Overall, the secondary metabolites were influenced by the three factors studied, whereas the primary metabolites were only by the seasonality. Chenin Blanc wines made in December presented higher content of an unidentified carbohydrate. In Syrah wines, glycerol, tartaric acid, succinic acid and 2,3-butanediol were greater in December, while proline and lactic acid were more abundant in July. For training system, caffeic acid derivatives were increased in wines produced from espalier. Lyre system increased phenolic compounds, organic acids and apocarotenoids. The effect of the rootstocks was less pronounced, affecting basically caffeic acid derivatives. Thus, we expect that our results may assist the winemakers to improve the SFRV wine quality.


Asunto(s)
Agricultura/métodos , Espectroscopía de Resonancia Magnética/métodos , Espectrometría de Masas/métodos , Vino/análisis , Brasil , Cromatografía Liquida/métodos , Análisis de los Alimentos/métodos , Metabolómica/métodos , Fenoles/análisis , Estaciones del Año , Metabolismo Secundario , Vitis/química , Vitis/metabolismo
15.
Artículo en Inglés | MEDLINE | ID: mdl-31071579

RESUMEN

The classical approach to drug discovery from natural products (NP's) requires strenuous and complex purification steps for the isolation and structural elucidation. Modern strategies as dereplication aim to accelerate the identification of known compounds present in a crude or partially purified extract. In this work, we investigated the influence of the solid-phase extraction (Oasis, Plexa, and Agilent C18 cartridges with and without organic modifiers) chemical profile obtained by UPLC-QTOF-MS and NMR and cytotoxicities of aqueous extracts from Phyllanthus niruri and P. amarus. Our results showed differences between the SPE cartridges and the mass recovered. P. niruri showed higher mass recovery than P. amarus indicating a higher amount of secondary metabolites. The UPLC-QTOF-MS analysis revealed that P. niruri crude extract presents higher contents of phenolic compounds than P. amarus. According to NMR analysis, P. niruri contained more tyrosine, corilagin, and glycosidic residues while P. amarus, presented higher content of ellagic acid. The different stationary phases, as well as mobile phases for exploratory SPE, enabled the exploitation of the different chemical functionalities within the Phyllanthus species. The SPE (MeOH:H2O 70:30 with C18 cartridges) samples showed greater in vitro cytotoxicity than the crude extracts, with IC50 ranging from 8.01 to 94.92 µg mL-1 against the tumor lines tested. The solid phase extraction allowed the concentration of molecules with desirable physicochemical characteristics, which might increase the hit of therapeutically useful substances.


Asunto(s)
Supervivencia Celular/efectos de los fármacos , Cromatografía Líquida de Alta Presión/métodos , Phyllanthus/química , Extractos Vegetales/farmacología , Extracción en Fase Sólida/métodos , Antineoplásicos/química , Antineoplásicos/farmacología , Línea Celular Tumoral , Proliferación Celular/efectos de los fármacos , Descubrimiento de Drogas , Humanos , Espectroscopía de Resonancia Magnética/métodos , Espectrometría de Masas/métodos , Extractos Vegetales/química , Hojas de la Planta/química
16.
Sci Rep ; 8(1): 15141, 2018 10 11.
Artículo en Inglés | MEDLINE | ID: mdl-30310165

RESUMEN

The Phyllanthus genus is widely distributed in tropical and subtropical areas of the world and present several pharmacological applications. Drought is a restrictive factor for crop development and production, and is becoming a severe problem in many regions of the world. The species Phyllanthus amarus and Phyllanthus niruri were subjected to drought stress for varying periods of time (0, 3, 5, 7, and 10 days), and afterwards, leaves were collected and evaluated for physiological and biochemical responses, such as oxidative stress markers and drought-associated defense mechanisms. Results show that P. amarus has an endogenously higher level of variables of the oxidative/antioxidant metabolism, and P. niruri presents the most significant changes in those variables when compared to control and stressed plants. For both Phyllanthus species, drought stress induces higher levels of organic acids such as malic, succinic, and citric acids, and amino acids such as proline, GABA, alanine, and valine. Moreover, P. niruri plants respond with greater glucose and corilagin contents. Therefore, considering the evaluated metabolic changes, P. amarus is better adapted to drought-stress, while P. niruri presents an acclimation strategy that increases the corilagin levels induced by short-term drought stress.


Asunto(s)
Adaptación Biológica , Sequías , Phyllanthus/fisiología , Estrés Fisiológico , Antioxidantes/metabolismo , Cromatografía Líquida de Alta Presión , Espectroscopía de Resonancia Magnética , Metabolómica/métodos , Estrés Oxidativo
17.
J Pharm Biomed Anal ; 153: 29-36, 2018 May 10.
Artículo en Inglés | MEDLINE | ID: mdl-29459233

RESUMEN

Several flavoring and sweetening agents added to excipient of pediatric syrups are not declared in the package leaflet. Therefore, the aim of this study was to develop a non-target, simple, and precise method for qualitative and quantitative evaluation of pediatric syrups using NMR spectroscopy combined with chemometrics. This approach allowed the identification of several added compounds as citric acid, cyclamate, ethanol, glycerol, propylene glycol, saccharin, sorbitol, fructose, glucose, and sucrose. Among the sugared syrups, sucrose was the main carbohydrate with approximately 59.1%, and for sweetened syrups, glycerol with 25.5%. The ethanol was found with highest concentration of 4.0%, approximately. In addition, some syrups presented both sugar and sweetener, which is inconsistent according to the purpose of the addition. Consequently, institutional structures of countries as Brazil that are in charge of public health should put additional compliance pressure on pharmaceutical companies to clearly declare in package leaflet the presence and exact amount of the main compounds (at least) existent in the pediatric excipients.


Asunto(s)
Excipientes/química , Preparaciones Farmacéuticas/química , Edulcorantes/química , Brasil , Etiquetado de Medicamentos/métodos , Estudios de Evaluación como Asunto , Humanos , Espectroscopía de Resonancia Magnética , Pediatría
18.
Talanta ; 180: 329-336, 2018 Apr 01.
Artículo en Inglés | MEDLINE | ID: mdl-29332819

RESUMEN

The genus Ocimum (Labiatae) comprises 30 species found in tropical and subtropical regions of the planet, of which species O. basilicum L. and O. gratissimum are widely used in food and traditional medicine. Phytochemical studies on Ocimum have revealed a number of essential oil chemotypes, for example, eugenol, methyl chavicol, linalool, and methyl cinnamate. Since essential oils are commercially assessed according to their content, the aim of this study was to develop a simple and precise method for their qualitative and quantitative analysis using NMR spectroscopy combined with chemometrics. Seven essential oils from different species of Ocimum, an unknown sample, and a commercial sample were evaluated and the results compared to those from established and precise GC-MS and GC-FID methods. Chemometric evaluation from both 1H NMR and GC-MS data revealed three chemotypes: eugenol for O. gratissimum, O. micranthum, and O. tenuiflorum; estragole for O. basilicum, O. basilicum var. purpuracens, and O. selloi; and methyl cinnamate for O. americanum. The unknown and commercial species were classified as cinnamate and eugenol chemotypes, respectively. Despite the corroborating results, the chemometric analysis revealed the higher robustness (better adjustment) of the 1H NMR model compared to the GC-MS method in terms of certain statistical parameters. The 1H NMR method allows for the detection and quantification of organic compounds in a complex mixture without the need for certified standard compounds. Although GC-MS and GC-FID were able to detect five compounds not observed by NMR spectroscopy, the four most important metabolites (eugenol, estragole, methyl cinnamate, and eucalyptol) were more readily detected and quantified by 1H NMR.


Asunto(s)
Cromatografía de Gases/métodos , Espectroscopía de Resonancia Magnética/métodos , Ocimum/química , Aceites Volátiles/análisis , Aceites de Plantas/análisis , Monoterpenos Acíclicos , Derivados de Alilbenceno , Anisoles/análisis , Cinamatos/análisis , Ciclohexanoles/análisis , Eucaliptol , Eugenol/análisis , Cromatografía de Gases y Espectrometría de Masas/métodos , Monoterpenos/análisis
19.
Food Chem ; 265: 23-31, 2018 Nov 01.
Artículo en Inglés | MEDLINE | ID: mdl-29884378

RESUMEN

The effects of thermal (pasteurization and sterilization) and non-thermal (ultrasound and plasma) processing on the composition of prebiotic and non-prebiotic acerola juices were evaluated using NMR and GC-MS coupled to chemometrics. The increase in the amount of Vitamin C was the main feature observed after thermal processing, followed by malic acid, choline, trigonelline, and acetaldehyde. On the other hand, thermal processing increased the amount of 2-furoic acid, a degradation product from ascorbic acid, as well as influenced the decrease in the amount of esters and alcohols. In general, the non-thermal processing did not present relevant effect on juices composition. The addition of prebiotics (inulin and gluco-oligosaccharides) decreased the effect of processing on juices composition, which suggested a protective effect by microencapsulation. Therefore, chemometric evaluation of the 1H qNMR and GC-MS dataset was suitable to follow changes in acerola juice under different processing.


Asunto(s)
Manipulación de Alimentos/métodos , Jugos de Frutas y Vegetales/análisis , Informática , Malpighiaceae/química , Prebióticos/análisis , Temperatura , Cromatografía de Gases y Espectrometría de Masas , Espectroscopía de Resonancia Magnética
20.
Food Chem ; 219: 1-6, 2017 Mar 15.
Artículo en Inglés | MEDLINE | ID: mdl-27765203

RESUMEN

Thermal food processing mainly aims to control microorganism in order to extend its shelf life. However, it may induce chemical and nutritional changes in foodstuff. The Nuclear Magnetic Resonance (NMR) coupled to multivariate analysis was used to evaluate the effect of different thermal processing conditions (85 and 140°C for 4; 15; 30; and 60s) on the passion fruit juice using an Armfield pasteurizer. Through this approach it was possible to identify the changes in the juice composition. The temperature and the time lead to a hydrolysis of the sucrose to glucose and fructose. Additionally, juice submitted to 140°C for 60s results in the degradation of the sucrose and the formation of 5-(hydroxymethyl)-2-furfural (HMF). Despite no novel chemical marker has been identified, the 1H NMR chemometrics approach may contribute in the choice of the temperature and time to be employed in the juice processing.


Asunto(s)
Jugos de Frutas y Vegetales/análisis , Espectroscopía de Resonancia Magnética/métodos , Temperatura , Manipulación de Alimentos , Reacción de Maillard
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