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1.
Plants (Basel) ; 13(19)2024 Sep 24.
Artículo en Inglés | MEDLINE | ID: mdl-39409545

RESUMEN

Humulus lupulus, or hops, is a vital ingredient in brewing, contributing bitterness, flavor, and aroma. The female plants produce strobiles rich in essential oils and acids, along with bioactive compounds like polyphenols, humulene, and myrcene, which offer health benefits. This study examined the aromatic profiles of five hop varieties grown in Brazil versus their countries of origin. Fifty grams of pelletized hops from each strain were collected and analyzed using HS-SPME/GC-MS to identify volatile compounds, followed by statistical analysis with PLS-DA and ANOVA. The study identified 330 volatile compounds and found significant aromatic differences among hops from different regions. For instance, H. Mittelfrüher grown in Brazil has a fruity and herbaceous profile, while the German-grown variety is more herbal and spicy. Similar variations were noted in the Magnum, Nugget, Saaz, and Sorachi Ace varieties. The findings underscore the impact of terroir on hop aromatic profiles, with Brazilian-grown hops displaying distinct profiles compared to their counterparts from their countries of origin, including variations in aromatic notes and α-acid content.

2.
Food Res Int ; 191: 114735, 2024 Sep.
Artículo en Inglés | MEDLINE | ID: mdl-39059967

RESUMEN

The present study was carried out to investigate the proximate composition, fatty acid (FA) profile and volatile compounds (VC) of cooked green licuri (Syagrus coronata) - an unripe stage that is then cooked - and naturally ripe licuri almonds. The FA profiles were determined by gas chromatography (GC) and the VC composition was evaluated using headspace-solid-phase microextraction coupled with GC-MS. The cooked green licuri presented higher moisture, and lower contents of ashes, proteins and lipids than naturally ripe licuri almonds. The FA profiles of cooked green licuri and naturally ripe licuri almonds showed that saturated FAs were predominant (80%) in both samples, and the concentrations of lauric, palmitic, and oleic acids in naturally ripe licuri almonds were higher than those in cooked green licuri. Limonene was the predominant compound in naturally ripe licuri almonds. The main class of VC in the cooked green licuri were aldehydes, with 3-methyl-butanal and furfural being the main species. Alcohols, such as 3-methyl-butanol and 2-heptanol, were the main class of VC in naturally ripe licuri almonds. Among the volatile compounds, 1-hexanol and 2-nonanone contributed to the aroma of cooked green licuri almonds, whereas 2-heptanone, ethanol, and limonene contributed to the aroma of naturally ripe licuri almonds (almonds not subjected to any cooking process). In a word, cooked green licuri and naturally riped licuri almonds, despite having different proximate compositions, present similar fatty acid profile and distinct aromatic characteristics. Therefore, cooked green licuri and naturally riped licuri almonds are an alternative source of nutrient and could be investigated for the use in the food industry to enhance flavor and aroma to new products.


Asunto(s)
Culinaria , Ácidos Grasos , Cromatografía de Gases y Espectrometría de Masas , Compuestos Orgánicos Volátiles , Compuestos Orgánicos Volátiles/análisis , Ácidos Grasos/análisis , Brasil , Microextracción en Fase Sólida , Ciclohexenos/análisis , Terpenos/análisis , Limoneno/análisis , Odorantes/análisis , Ácido Palmítico/análisis , Ácido Oléico/análisis , Aldehídos/análisis , Ácidos Láuricos/análisis , Pentanoles/análisis
3.
Plants (Basel) ; 12(22)2023 Nov 20.
Artículo en Inglés | MEDLINE | ID: mdl-38005802

RESUMEN

The present work was conducted to evaluate the volatile profile of Ecuadorian Forastero, CCN-51, ETT103 and LR14 cocoa beans during traditional fermentation in laurel wood boxes followed by a sun-drying process. Fifty-six volatiles were identified with HS-SPME-GC-MS. Aldehydes, alcohols and ketones were the compounds that mainly characterized the fresh cocoa. The main compounds formed during the anaerobic fermentation step were esters and acids, while in the aerobic fermentation step, an increase in ester-, aldehyde- and acid-type compounds was observed. Finally, after the drying step, a notable increase in the acid (i.e., acetic acid) content was the predominant trend. According to the genotypes, ETT103 presented high contents of terpenes, alcohols, aldehydes and ketones and low contents of unfavorable acid compounds. The CCN-51 and LR14 (Trinitarian) varieties stood out for their highest amounts in acids (i.e., acetic acid) at the end of primary processing. Finally, the Forastero cocoa beans were highlighted for their low acid and high trimethylpyrazine contents. According to the chemometric and Venn diagram analyses, ETT-103 was an interestingly high-aromatic-quality variety for cocoa gourmet preparations. The results also showed the need for good control of the processing steps (using prefermentative treatments, starter cultures, etc.) on Ecuadorian genotypes of Trinitarian origin.

4.
Food Res Int ; 169: 112938, 2023 07.
Artículo en Inglés | MEDLINE | ID: mdl-37254362

RESUMEN

Aiming to improve the quality of cocoa, preconditioning of cocoa after harvesting and before fermentation has become an on-farm processing step of great interest in recent times. The present work aimed to evaluate the influence of a pre-drying process on the volatile composition of Ecuadorian bulk (Forastero and CCN-51) and fine-flavour (ETT103 and LR14) cocoa at the end of primary processing. A total of 63 volatile compounds including aldehydes, alcohols, acids, ketones, esters, terpenes, lactones and other miscellaneous compounds were identified in cocoa samples by HS-SPME-GC-MS. The use of a pre-drying step revealed a varietal homogenization and a reduction in the fermentation time, making this preconditioning step an inexpensive and attractive option for farmers. Moreover, different varietal behaviour was observed after pre-drying, the fine-flavour varieties obtaining a clear improvement in aromatic quality with higher levels of compounds imparting positive notes.


Asunto(s)
Cacao , Chocolate , Ecuador , Granjas , Chocolate/análisis , Cromatografía de Gases y Espectrometría de Masas
5.
Foods ; 12(5)2023 Mar 02.
Artículo en Inglés | MEDLINE | ID: mdl-36900586

RESUMEN

Cocoa (Theobroma cacao L.) is one of the most widely consumed edible seeds in the world affected by on-farm processing. This study investigated the effect of different drying techniques, namely oven drying (OD), sun drying (SD), and a modification of sun drying using black plastic sheeting (SBPD), on the volatile profile of fine-flavor and bulk cocoa varieties analyzed by HS-SPME-GC-MS. A total of sixty-four volatile compounds were identified in fresh and dried cocoa. As expected, the volatile profile was clearly modified after the drying step, showing strong differences among cocoa varieties, this factor and its interaction with the drying technique having greater influence according to the ANOVA simultaneous component analysis. A principal component analysis revealed a close relationship between the volatile content of bulk cocoa samples dried by the OD and SD techniques, whereas slight volatile modifications were perceived among fine-flavor samples dried using the three different techniques under study. Overall, the results provide the basis for the potential application of the simplest inexpensive SBPD technique in order to accelerate the drying process of sun drying and produce cocoa with similar (fine-flavor cocoa) or improved (bulk cocoa) aromatic quality to that formed using the traditional SD or the small-scale OD.

6.
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
7.
Bull Environ Contam Toxicol ; 108(6): 1139-1146, 2022 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-35303142

RESUMEN

The biomass conversion technologies, especially different types of pyrolysis, have been intensively studied to improve biomass energy transformation suggesting a low impact on the environment. In particular, fast pyrolysis of biomass is considered to be a thermal process in which the starting material is converted to bio-oil, char and gas products. In this work, volatile organic compounds (VOCs) of the gaseous fraction of peanut shells fast pyrolysis were collected and identified at atmospheric pressure. Aromatic compounds, hydrocarbons, furans and other oxygenated compounds were identified using solid phase microextraction (SPME) and gas chromatography coupled to mass spectrometry (CG-MS) as a detection system. The composition of volatiles was analyzed and compared with the constituents of liquid fraction for comparative purposes. Atmospheric implications of the main compounds identified in the gases fraction were assessed by determining tropospheric lifetimes of the VOCs identified and its impact on environment at the local, regional or global scale.


Asunto(s)
Compuestos Orgánicos Volátiles , Arachis , Cromatografía de Gases y Espectrometría de Masas/métodos , Gases , Pirólisis , Microextracción en Fase Sólida/métodos , Compuestos Orgánicos Volátiles/análisis
8.
Heliyon ; 7(8): e07694, 2021 Aug.
Artículo en Inglés | MEDLINE | ID: mdl-34401578

RESUMEN

Two artisanal fermentation processes for Criollo cocoa beans with different turning start times (24 h and 48 h) were studied. The aromatic profile of cocoa turned every 24 h (B1) displayed volatile compounds associated with fermented, bready, and fruity aromas. When cocoa beans were fermented with a different turning technique with a start time of 48 h (B2), they provided volatile compounds mainly associated with descriptors of floral, woody, sweet, fruity and chocolate aromas. The turning start time of 48 h stimulated a microbial profile dominated by yeast such as Hanseniaspora opuntiae, Pichia manshurica, and Meyerozyma carpophila, favoring the production of several key aroma markers associated with cocoa bean fermentation quality, such as phenylethyl acetate, 2-phenylacetaldehyde, 3-methylbutanal, 2-phenylethyl alcohol, 2,3-butanedione, 3-methylbutanoic acid, and 2-methylpropanoic acid, while an immediate turning start time (24 h) favored an aerobic environment that stimulated the rapid growth of Acetobacter pasteurianus, Bacillus subtilis and a higher biodiversity of lactic acid bacteria (LAB) (e.g., Lactobacillus plantarum and Pediococcus acidilactici), which increased the production of ethyl acetate and 3-hydroxy-2-butanone. Volatile compound generation and microbial populations were evaluated and analyzed by multivariate analysis (principal component analysis and partial least squares discriminant analysis) to find correlations and significant differences. This study shows that the method of turning Criollo cacao beans can lead to the formation of desirable aromatic compounds.

9.
Front Zool ; 18(1): 39, 2021 Aug 26.
Artículo en Inglés | MEDLINE | ID: mdl-34446035

RESUMEN

BACKGROUND: Poison frogs are known for the outstanding diversity of alkaloid-based chemical defences with promising therapeutic applications. However, current knowledge about chemical defences in Dendrobatoidea superfamily has two sources of bias. First, cryptic, brown-colored species have been neglected in comparison to those conspicuously colored, and second, there has been little interest in characterizing metabolites other than alkaloids mediating defensive functions. In an effort to contribute to fill the gap of knowledge about cryptic species and broadening the spectrum of compounds analyzed we have applied head-space solid phase microextraction coupled to gas chromatography and mass spectrometry (HS-SPME/GC-MS) for extracting amphibian alkaloids and volatile organic compounds (VOCs) from Silverstoneia punctiventris. RESULTS: Using the skin from 8 specimens in 4 biological replicates we have found 33 different compounds. Twenty of them were classified as VOCs into 15 chemical classes including alkanes, alcohols, carbonyl compounds, methylpyridines, benzothiazoles, N-alkylpyrrolidines, pyrazines, and sesquiterpenoids, some of which were previously reported as repellents, defence compounds or defence pheromones in other organisms, and as sex pheromones in a treefrog. Interestingly, six of the remaining compounds were identified as alkaloids previously reported in other toxic/unpalatable dendrobatid frogs. CONCLUSIONS: This is the first report of alkaloids and VOCs found in the Silverstoneia genus, which has been assumed for decades as non-chemically defended. This study establishes HS-SPME/GC-MS as a new application for a simultaneous approach to amphibian alkaloids and VOCs in poison frogs while opens up new research questions to assess the co-occurrence of both type of compounds and to investigate the evolutionary significance of a defence gradient that includes olfactory avoidance, unpalatability, and toxicity in dendrobatids. In addition, our results show that amphibian alkaloids could have a dual function (olfactory at distance, taste by contact) never explored before neither in Silverstonaeia nor in any other dendrobatid species.

10.
J Environ Sci Health B ; 55(11): 983-989, 2020.
Artículo en Inglés | MEDLINE | ID: mdl-32795113

RESUMEN

A solid-phase microextraction (SPME) coupled to gas chromatography-mass spectrometry method was validated for the simultaneous determination of penconazole, cyproconazole, epoxiconazole, deltamethrin, azoxystrobin and kresoxim-methyl in paddy rice irrigation water. Different SPME fiber coatings and pH values were tested. Polydimethylsiloxane (PDMS) and pH 7 were chosen to optimize extraction. All pesticides presented a recovery percentage between 90.5 and 104.2%; and detection and quantification limits were 0.03 and 0.05 µg/kg for azoxystrobin and cyproconazole, 0.02 and 0.05 µg/kg for deltametrhin and epoxiconazole, 0.02 and 0.03 µg/kg for kresoxim-methyl, and 0.01 and 0.02 µg/kg for penconazole. The expanded uncertainty was estimated for all pesticides showing results lower than 20%. A total of 100 paddy rice irrigation water samples, collected in different rice fields from Argentina, were evaluated. The study showed that 86 of them presented residues. The concentrations exceeded the values that were set by European legislation and the frequencies were higher than 86% so the agricultural practices should be revised.


Asunto(s)
Riego Agrícola , Oryza , Plaguicidas/análisis , Contaminantes Químicos del Agua/análisis , Riego Agrícola/métodos , Argentina , Productos Agrícolas , Cromatografía de Gases y Espectrometría de Masas/métodos , Concentración de Iones de Hidrógeno , Límite de Detección , Microextracción en Fase Sólida/métodos , Encuestas y Cuestionarios , Incertidumbre
11.
Food Res Int ; 130: 108943, 2020 04.
Artículo en Inglés | MEDLINE | ID: mdl-32156387

RESUMEN

Cocoa products are obtained from the seeds of Theobroma cacao L. In this research, cocoa liquor and chocolate produced from cocoa beans from West Africa (Forastero, "bulk" cacao) and Ecuador (Nacional variety, "fine-flavor" cacao), were investigated, using a novel approach in which various analytical techniques are combined in order to obtain in-depth knowledge of the studied cocoa samples. The levels of various classes of primary metabolites were determined and a wide range of secondary metabolites, including volatile organic acids, aldehydes, esters, pyrazines, polyphenols, methylxanthines and biogenic amines, were identified and/or quantified by HS-SPME GC-MS (headspace-solid phase microextraction gas chromatography - mass spectrometry). and UPLC-HRMS (ultra-performance liquid chromatography - high resolution mass spectrometry). Odor Activity Values (OAV) were calculated to assess the contribution of individual volatiles on the final aroma. Various volatile aroma compounds were more abundant in the West African cocoa liquor and chocolate, while the Ecuadorian samples were richer in most quantified non-volatile metabolites. Principal component analysis (PCA) confirmed that the four samples can be clearly distinguished. Alcohols, pyrazines, amino acids and biogenic amines were found to be highly influential in causing this differentiation. The proposed approach can be useful in future studies on more extensive cocoa sample collections, in order to highlight similarities and pinpoint typical differences in chemical composition among these samples.


Asunto(s)
Chocolate/análisis , Chocolate/normas , Cromatografía Liquida/métodos , Cromatografía de Gases y Espectrometría de Masas/métodos , Compuestos Orgánicos Volátiles/química , África Occidental , Ecuador , Manipulación de Alimentos
12.
Meat Sci ; 164: 108110, 2020 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-32179387

RESUMEN

The aim of this study was to investigate the effect of using different reforestation woods (Acacia mearnsii and Eucalyptus citriodora) on the formation of volatile organic compounds and to evaluate the changes in the lipid fraction (peroxide value and thiobarbituric acid reactive substances), microbiological counts and overall liking in bacons stored for 60 days at 5 ± 1 °C. Smoking with Eucalyptus citriodora wood increased the total phenolic content and, consequently, reduced the concentration of hexanal, TBARS, and PV values. Although smoking with different reforestation woods did not impact negatively on the liking of products, no changes on antimicrobial activity was observed in the developed products. Thus, the use of Eucalyptus citriodora wood may be an alternative for smoking meat products as it reduced lipid oxidation and improved the volatile compounds profile, and provided higher antioxidant activity. The information generated herein can be used as a platform for companies to test the viability of producing meat products smoked with reforestation woods.


Asunto(s)
Productos de la Carne/análisis , Humo , Madera , Acacia , Animales , Brasil , Comportamiento del Consumidor , Eucalyptus , Femenino , Manipulación de Alimentos/métodos , Almacenamiento de Alimentos , Humanos , Metabolismo de los Lípidos , Masculino , Productos de la Carne/microbiología , Oxidación-Reducción , Porcinos , Sustancias Reactivas al Ácido Tiobarbitúrico/análisis , Compuestos Orgánicos Volátiles/análisis
13.
Antioxidants (Basel) ; 9(1)2020 Jan 13.
Artículo en Inglés | MEDLINE | ID: mdl-31940981

RESUMEN

Propolis is a complex mixture of natural sticky and resinous components produced by honeybees from living plant exudates. Globally, research has been dedicated to studying the biological properties and chemical composition of propolis from various geographical and climatic regions. However, the chemical data and biological properties of Mexican brown propolis are scant. The antioxidant activity of the ethanolic extract of propolis (EEP) sample collected in México and the isolated compounds is described. Cytotoxic activity was evaluated in a central nervous system and cervical cancer cell lines. Cytotoxicity of EEP was evaluated in a C6 cell line and cervical cancer (HeLa, SiHa, and CasKi) measured by the 3-(3,5-dimethylthiazol-2-yl)2,5-diphenyltetrazolium (MTT) assay. The antibacterial activity was tested using the minimum inhibitory concentration (MIC) assay. Twelve known compounds were isolated and identified by nuclear magnetic resonance spectroscopy (NMR). Additionally, forty volatile compounds were identified by means of headspace-solid phase microextraction with gas chromatography and mass spectrometry time of flight analysis (HS-SPME/GC-MS-TOF). The main volatile compounds detected include nonanal (18.82%), α-pinene (12.45%), neryl alcohol (10.13%), and α-pinene (8.04%). EEP showed an anti-proliferative effect on glioma cells better than temozolomide, also decreased proliferation and viability in cervical cancer cells, but its effectiveness was lower compared to cisplatin.

14.
Food Chem ; 310: 125943, 2020 Apr 25.
Artículo en Inglés | MEDLINE | ID: mdl-31816532

RESUMEN

The interactions between edaphoclimatic factors, forms of processing, drying, storage and roasting, directly affect the sensorial results. This study applied four forms of wet-processing in six different altitude strata, aiming to potentiate the final quality of the drink. The final quality of the coffees was measured using the sensory technique and HS-SPME-GC/MS analyses. Results indicate that the use of starter culture in the fermentation phase constitutes a relevant alternative for lower-altitude zones, and that spontaneous fermentations have a higher potential of sensorial results at above 900 m. In the sequence, the volatile compounds were affected according to the type of processing and the altitude. The compounds in general that contributed the most to the formation of the math models were: 2-furylmethanol, octadecanal, 2-acetyl-3-methylpyrazine, 2,3-Dihydro-3,5-dihydroxy-6-methyl-4H-pyran-4-one (DDMP) and caffeine. The positive effects of the fermentation corroborate with new sensory routes, modification of the flavor and volatile compounds, consequently, generating new fermentation strategies.


Asunto(s)
Café/química , Manipulación de Alimentos/métodos , Altitud , Brasil , Cafeína/análisis , Café/microbiología , Desecación , Fermentación , Calidad de los Alimentos , Cromatografía de Gases y Espectrometría de Masas/métodos , Humanos , Odorantes/análisis , Saccharomyces cerevisiae , Gusto , Compuestos Orgánicos Volátiles/análisis
15.
Bol. latinoam. Caribe plantas med. aromát ; 18(5): 492-503, sept. 2019. tab, ilus
Artículo en Inglés | LILACS | ID: biblio-1008286

RESUMEN

The aim of the present work was to optimize the main experimental variables of a procedure using HS-SPME/GC-MS as the analytical methodology to establish the profile of the volatile compounds present in aerial parts of Hedeoma multiflorum Benth. The influence of the type of fiber, equilibrium time, extraction time and extraction temperature on the composition of the volatile compounds was determined using response surface methodology (RSM), and the parameters of the models were corroborated by multiple linear regressions. The results showed that the regression models generated adequately explained the data variation and represented the relationships between the parameters and their responses. The optimal analysis conditions from the contour plots were established (DVB/CAR/PDMS fiber, with a 10 min equilibrium time, 10 min extraction time, and 40°C). Under these conditions, 41 volatile components in the whole plant were determined, which represents more than those reported using hydrodistillation.


El objetivo del presente trabajo fue optimizar las principales variables experimentales de un procedimiento HS-SPME/GC para establecer el perfil de compuestos volátiles presentes en la parte aérea de Hedeoma multiflorum Benth. Se determinó la influencia de las variables tipo de fibra, tiempo de equilibrio, tiempo de extracción y temperatura de extracción sobre la composición de los volátiles, utilizando una met odología de superficie de respuesta (RSM) y los parámetros del modelo se corroboraron por regresión lineal múltiple. Los resultados demostraron que los modelos de regresión generados explican adecuadamente la variación de los datos y representaron significativamente las relaciones reales entre los parámetros y sus respuestas. Las condiciones óptimas de análisis fueron establecidas (DVB/CAR/PDMS, con un tiempo de equilibrio de 10 minutos, un tiempo de extracción de 10 minutos y trabajando a 40°C). Utilizando esta metodología, se determinaron 41 componentes volátiles en planta entera, más que los reportados mediante hidrodestilación.


Asunto(s)
Hedeoma , Microextracción en Fase Sólida/métodos , Compuestos Orgánicos Volátiles/química , Cromatografía de Gases y Espectrometría de Masas/métodos
16.
Molecules ; 24(16)2019 Aug 15.
Artículo en Inglés | MEDLINE | ID: mdl-31443290

RESUMEN

Background. There is no gold standard method for human skin odor determination; several techniques can be applied to collect, extract, transfer, and detect human skin odors. However, none of these methods are suitable for field sampling of a large number of individuals. Objective. The present study aimed to develop a simple, fast, non-invasive, and low-cost method for such a purpose. Methods. Considering that hair from legs can act as a retention mesh of volatile organic compounds (VOCs), samples of leg hairs provided by healthy adult males were collected and solid-phase microextraction (SPME), in headspace (HS) mode, coupled to gas chromatography (GC) and mass spectrometry (MS) analysis of the samples was carried out. A pilot test was applied to detect five quality markers that are frequently reported in human skin odors. Then, several steps were performed for method standardization. The method was applied to 36 different individuals (3 sampled under laboratory conditions and 33 under field conditions), aiming to evaluate its applicability in both environments. Findings. A total of 49 VOCs were identified, and 73.5% of these have been reported in previous studies. Main Conclusions. Hair from legs can be considered an efficient tool for human skin odor sampling and a suitable and practical matrix for human skin odor profile determination by using HS-SPME/GC-MS.


Asunto(s)
Cabello/química , Odorantes/análisis , Piel/metabolismo , Análisis de Varianza , Cromatografía de Gases y Espectrometría de Masas , Humanos , Microextracción en Fase Sólida , Compuestos Orgánicos Volátiles/análisis , Compuestos Orgánicos Volátiles/química , Compuestos Orgánicos Volátiles/aislamiento & purificación
17.
Metabolomics ; 15(6): 91, 2019 06 12.
Artículo en Inglés | MEDLINE | ID: mdl-31190244

RESUMEN

INTRODUCTION: Mikania laevigata Sch.Bip. ex Baker and Mikania glomerata Spreng. are medicinal plants popularly known as guaco, used for inflammatory diseases of the respiratory system, included in pharmaceutical formularies and often used without distinction. However, several studies show that the chemical composition varies between these species, as well as in plants are subjected to different environmental stresses. Few studies have been carried out with the volatile compounds of guaco, even less about the changes in volatile composition due to abiotic variation. OBJECTIVE: The aim of this work was to evaluate how volatile compounds vary according to the seasons and at different times of the day and if these compounds are influenced by the variations in the growth conditions such as: temperature, luminosity and water. METHODS: The headspace volatiles of the leaves were sampled by solid phase micro extraction and analyzed by gas chromatography-mass spectrometry. Untargeted metabolomic analysis of the resulting chromatograms and chemometrics was applied. The chemical profile of the volatiles of M. laevigata and M. glomerata were different; being clearly separated in the exploratory grouping analyzes (PCA), followed by analysis of variance of the marker compounds of both species. RESULTS: Only M. laevigata contained coumarin, considered to be the chemical marker of both species and to be responsible for the therapeutic activities. There was no significant difference between the morning and afternoon collections of either species. Coumarin, α-pinene and bicyclogermacrene were more intense in the volatiles of M. laevigata throughout the year and responsible for grouping the samples of this species. For M. glomerata, hexanal and 2-hexenal were responsible for grouping the samples and were more intense in all months. The growth conditions tested affected the intensity of specific compounds in the chromatograms. Some compounds were less intense with the increase of the temperature and in the plants subjected to full sunlight. However, certain volatile compounds-such as pinenes-were more intense in plants suffering drought. CONCLUSION: The variation in composition between species of guaco was greater than those observed in the seasonal and cultivation studies, indicating that these species cannot be used indistinctly.


Asunto(s)
Mikania/metabolismo , Plantas Medicinales/metabolismo , Compuestos Orgánicos Volátiles/metabolismo , Monoterpenos Bicíclicos/análisis , Monoterpenos Bicíclicos/metabolismo , Brasil , Cumarinas/análisis , Cumarinas/metabolismo , Sequías , Mikania/química , Plantas Medicinales/química , Sesquiterpenos de Germacrano/análisis , Sesquiterpenos de Germacrano/metabolismo , Estrés Fisiológico , Temperatura , Compuestos Orgánicos Volátiles/análisis
18.
Anal Bioanal Chem ; 411(14): 3209-3218, 2019 May.
Artículo en Inglés | MEDLINE | ID: mdl-30976896

RESUMEN

A method was developed for the simultaneous determination of two groups of personal care products, namely UV filters (oxybenzone, 3-(4-methylbenzylidene)camphor, padimate-O, 2-ethylhexyl-4-methoxycinnamate, and octocrylene) and polycyclic aromatic musks (galaxolide and tonalide), in fish by in vivo solid-phase microextraction followed by gas chromatography-mass spectrometry. The in vivo method was validated by carrying out in vitro experiments; the method validation parameters were linearity (r2 > 0.98), interday precision (relative standard deviations < 35.50%), limits of detection and quantification ranging from 2 to 25 ng g-1 and 5 to 70 ng g-1, respectively. The calibrations in vivo and in vitro were determined using a pre-equilibrium sampling rate calibration method. In vivo sampling rate (Rs) was greater than that in vitro; therefore in vivo Rs was applied to the uptake and elimination tracing under controlled laboratory conditions to avoid quantitation error. All analytes were bioaccumulated in muscle tissue over the 5-day exposure in different grades depending on their molecular structure and physicochemical properties; the most absorbed compound was tonalide and the least absorbed compound was padimate-O. The elimination rate was initially high with a rapid decrease of the analyte concentrations for the first 24 h; thereafter, the rate of elimination tended to decrease which indicated that the target analytes were bioaccumulated. To our knowledge, this is the first time that UV filters have been analyzed with in vivo SPME-GC-MS. The proposed method is a simple, miniaturized, and non-lethal alternative for the determination of personal care products in living organisms. Graphical abstract.


Asunto(s)
Benzopiranos/análisis , Cosméticos/análisis , Peces , Cromatografía de Gases y Espectrometría de Masas/métodos , Microextracción en Fase Sólida/métodos , Protectores Solares/análisis , Tetrahidronaftalenos/análisis , Animales , Calibración , Límite de Detección , Reproducibilidad de los Resultados
19.
Food Res Int ; 119: 839-849, 2019 05.
Artículo en Inglés | MEDLINE | ID: mdl-30884723

RESUMEN

Bacon is a product made from pork meat that is subjected to curing, drying, and smoking. Researchers aim to associate the worldwide high-acceptance of such a product with the sensory and chemical properties of bacon. In this context, the objective of the present study was to characterize bacon samples smoked with different woods from reforestation using chemical and sensory methodologies, which were subsequently correlated by means of statistical multi-block analysis. Volatile compounds (VCs) of the smoked bacons were studied using solid-phase microextraction (SPME) coupled with gas chromatography-mass spectrometry (GC-MS), and the consumer sensory perception was explored by the Napping technique. VCs were identified in smoked samples, which triggered sensory attributes related to odor, flavor, and texture, such as "smoky flavor", "salty taste", "pleasant taste", "woodsy flavor", and "hard texture". Multi-block analysis showed that the sensory attributes were associated with a group of VCs and not by a single compound.


Asunto(s)
Carne de Cerdo , Gusto , Compuestos Orgánicos Volátiles/análisis , Madera/química , Acacia , Aldehídos/análisis , Brasil , Eucalyptus , Aromatizantes/análisis , Cromatografía de Gases y Espectrometría de Masas , Cetonas/análisis , Productos de la Carne/análisis , Odorantes/análisis , Fenoles/análisis , Humo , Microextracción en Fase Sólida
20.
Food Res Int ; 119: 84-98, 2019 05.
Artículo en Inglés | MEDLINE | ID: mdl-30884724

RESUMEN

The impact of pod storage (PS) and roasting temperature (RT) on the aroma profiles of dark chocolates were evaluated. Cocoa liquor samples comprised of ten different combinations of PS and RT, whilst keeping the roasting time fixed at 35 min. Additionally, commercial cocoa liquors from renowned origins (Ecuador, Madagascar, Venezuela, Vietnam, Ivory Coast and Ghana) were acquired for comparison. From these, 70% dark chocolates were produced under the same conditions after which they were subjected to headspace solid-phase microextraction-gas chromatography-mass spectrometry (HS-SPME-GC-MS) analysis. Although both PS and RT were found to influence the aroma volatile concentrations, the impact of RT over PS seemed to be greater. An agglomerative hierarchical clustering (AHC) of all chocolates on the basis of their aroma profiles revealed a similar impact as earlier observed, where major clustering of the chocolates was in accordance with the intensity of the roasting process applied. However, within each group, the dissimilarities owing to PS among the chocolates was clearly depicted. Comparatively, chocolates with low (100-120 °C), instead of moderate to high (135-160 °C) RT's, rather showed a low dissimilarity with those from the commercial cocoa liquors of the different origins. Although from the same beans, the diversity of aroma profiles of these chocolates as well as the similitude of some treatments to some chocolates from commercial grade cocoa liquors, unequivocally underscores the possibility for steering diverse distinct flavors from 'bulk' cocoa through PS and roasting, with beneficial implications, both from an application and an economic point of view.


Asunto(s)
Cacao/química , Chocolate/análisis , Manipulación de Alimentos , Almacenamiento de Alimentos , Odorantes/análisis , Gusto , Côte d'Ivoire , Ecuador , Ésteres/análisis , Furanos/análisis , Cromatografía de Gases y Espectrometría de Masas , Ghana , Madagascar , Piranos/análisis , Pirazinas/análisis , Pironas/análisis , Pirroles/análisis , Semillas/química , Microextracción en Fase Sólida , Terpenos/análisis , Venezuela , Vietnam , Compuestos Orgánicos Volátiles/análisis
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