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1.
Toxics ; 12(2)2024 Feb 09.
Artigo em Inglês | MEDLINE | ID: mdl-38393236

RESUMO

The aim of this work was to compare the potential induction of oxidative stress and the antioxidant enzymatic response after a short-term waterborne exposure to copper (Cu) and arsenic (As) with that of the nanoparticles (NPs) of these elements (Cu-NPs and As-NPs) in fish larvae of the species Dicentrarchus labrax. Larvae were grouped in several tanks and exposed to different concentrations of contaminants (0 to 10 mg/L) for 24 or 96 h under laboratory conditions. Copper and arsenic concentrations were analysed in larval tissues using ICP-MS. A set of oxidative stress biomarkers, including the levels of hydroperoxides (HPs), and superoxide dismutase (SOD) and catalase (CAT) activities were assessed. The trace element concentrations (mg/kg d.w.) in larvae ranged as follows: 3.28-6.67 (Cu at 24 h) and 2.76-3.42 (Cu at 96 h); 3.03-8.31 (Cu-NPs at 24 h) and 2.50-4.86 (Cu-NPs at 96 h); 1.92-3.45 (As at 24 h) and 2.22-4.71 (As at 96 h); and 2.19-8.56 (As-NPs at 24 h) and 1.75-9.90 (As-NPs at 96 h). In Cu tests, the oxidative damage (ROOH levels) was induced from 0.1 mg/L at both exposure times, while for Cu-NPs, this damage was not observed until 1 mg/L, which was paralleled by concomitant increases in SOD activity. The CAT activity was also increased but at lower metal concentrations (0.01 mg/L and 0.1 mg/L for both chemical forms). No oxidative damage was observed for As or As-NPs after 24 h, but it was observed for As after 96 h of treatment with 0.01 mg/L. A decrease in SOD activity was observed for As after 24 h, but it turned out to be increased after 96 h. However, As-NPs did not alter SOD activity. The CAT activity was stimulated only at 96 h by As and at 24 h by As-NPs. Therefore, the two chemical forms of Cu exhibited a higher bioaccumulation and toxicity potential as compared to those of As. Importantly, the association of both Cu and As in NPs reduced the respective trace metal bioaccumulation, resulting also in a reduction in the toxic effects (mortality and biochemical). Furthermore, the assessment of oxidative stress-related biomarkers in seabass larvae appears to be a useful tool for biomonitoring environmental-occurring trace elements.

2.
Pharmaceuticals (Basel) ; 16(5)2023 May 08.
Artigo em Inglês | MEDLINE | ID: mdl-37242498

RESUMO

The population is now more aware of their diets due to the connection between food and general health. Onions (Allium cepa L.), common vegetables that are minimally processed and grown locally, are known for their health-promoting properties. The organosulfur compounds present in onions have powerful antioxidant properties and may decrease the likelihood of developing certain disorders. It is vital to employ an optimum approach with the best qualities for studying the target compounds to undertake a thorough analysis of these compounds. In this study, the use of a direct thermal desorption-gas chromatography-mass spectrometry method with a Box-Behnken design and multi-response optimization is proposed. Direct thermal desorption is an environmentally friendly technique that eliminates the use of solvents and requires no prior preparation of the sample. To the author's knowledge, this methodology has not been previously used to study the organosulfur compounds in onions. Likewise, the optimal conditions for pre-extraction and post-analysis of organosulfur compounds were as follows: 46 mg of onion in the tube, a desorption heat of 205 °C for 960 s, and a trap heat of 267 °C for 180 s. The repeatability and intermediate precision of the method were evaluated by conducting 27 tests over three consecutive days. The results obtained for all compounds studied revealed CV values ranging from 1.8% to 9.9%. The major compound reported in onions was 2,4-dimethyl-thiophene, representing 19.4% of the total area of sulfur compounds. The propanethial S-oxide, the principal compound responsible for the tear factor, accounted for 4.5% of the total area.

3.
Food Chem ; 399: 133979, 2023 Jan 15.
Artigo em Inglês | MEDLINE | ID: mdl-35998494

RESUMO

The changes of capsaicinoids in the pericarp and placenta of Jeromin pepper fruits, collected at two different stages of plant's maturity (young and adult), has been studied throughout the ripening process. This variety is used in the production of "Pimentón de La Vera" and recognized under a Protected Designation of Origin, so it is of great importance to determine their optimum harvesting time to get the most of its beneficial health effects. Capsaicinoids reached the maximum concentration on the 30th days post-anthesis (dpa) for the young plant, while in the adult plant it was later, specifically on 40th and 60th dpa for the placenta and pericarp, respectively. From this moment on, a sharp decrease in their content is observed. In addition, higher amounts of total capsaicinoids have been found in the second stage of plant maturity with respect to the first one, both in the placenta and in the pericarp.


Assuntos
Capsicum , Piper nigrum , Capsaicina/análise , Frutas/química
4.
Antioxidants (Basel) ; 11(12)2022 Dec 02.
Artigo em Inglês | MEDLINE | ID: mdl-36552601

RESUMO

Nowadays, consumers demand bioactive foods that have the potential to limit the risk of suffering from several medical conditions. Onions present these desirable capabilities owing to its high content in antioxidant bioactive compounds. This work has used a Box-Behnken design with a response surface methodology to determine the best conditions in which to extract the polyphenols that are found in onions. Two extraction methods-one for the extraction of total flavonols and another one intended to obtain extracts with the highest possible antioxidant activity-have been developed and optimized. The following factors have been studied: temperature, %methanol in water, solvent pH, and sample-solvent volumetric ratio. The optimal conditions for the extraction of flavonols were 93.8% methanol in water, pH 2, 50 °C extraction temperature and 0.2:17.9 g:mL sample-solvent ratio. The best antioxidant activity levels were registered when using 74.2% methanol in water, pH 2, 99.9 °C extraction temperature and 0.2:18.2 g:mL sample-solvent ratio. Both optimized methods used short extraction times, and presented good precision levels and successful results when used with an assortment of onion varieties. According to total flavonols and antioxidant activity data, with 7.557 ± 0.3261 and 12.08 ± 0.0379 mg g-1, respectively, the developed methods achieved comparable or even superior results to those obtained by other authors.

5.
J Fungi (Basel) ; 8(12)2022 Dec 10.
Artigo em Inglês | MEDLINE | ID: mdl-36547625

RESUMO

Mushroom consumption has increased in recent years due to their beneficial properties to the proper functioning of the body. Within this framework, the high potential of mushrooms as a source of essential elements has been reported. Therefore, the present study aims to determine the mineral content of seven essential metals, Fe, Mg, Mn, P, K, Ca, and Na, in twenty samples of mushrooms of the genus Lactarius collected from various locations in southern Spain and northern Morocco, by FAAS, UV-Vis spectroscopy, and ICP-OES after acid digestion. Statistics showed that K was the macronutrient found at the highest levels in all mushrooms studied. ANOVA showed that there were statistically significant differences among the species for K, P, and Na. The multivariate study suggested that there were differences between the accumulation of the elements according to the geographic location and species. Furthermore, the intake of 300 g of fresh mushrooms of each sample covers a high percentage of the RDI, but does not meet the recommended daily intake (RDI) for any of the metals studied, except for Fe. Even considering these benefits, the consumption of mushrooms should be moderated due to the presence of toxic metals, which may pose health risks.

6.
Food Chem ; 393: 133417, 2022 Nov 01.
Artigo em Inglês | MEDLINE | ID: mdl-35691065

RESUMO

A fast, precise and inexpensive alternative for evaluating the antioxidant activity (AA) in walnut kernel extracts is proposed. Traditional ABTS assay and an electrochemical index approach have been applied to evaluate the AA in walnuts. A fast and efficient defatting of the walnuts by ultrasound assisted extraction (UAE) was carried out. Later, for the extraction of polyphenolic compounds, a procedure based on UAE in ethanolic medium was used. The AA of the sample ethanolic extracts was expressed as both % of inhibition by the ABTS spectrophotometric method and the electrochemical index approach (EI) obtained by the ratio between current and potential peak values using differential pulse voltammetry (DPV) at a Sonogel-Carbon electrode. The behaviour of the EI approach have been explored using six polyphenols standards and walnut kernel extracts at pH 2. All the polyphenols appeared at an oxidation potential between 0.476 and 0.778 V. Eleven samples available to consumers were analysed. A high significant correlation (R2 = 0.927) between the spectrophotometric measurements and the EI approach of the walnut extracts was obtained.


Assuntos
Antioxidantes , Juglans , Antioxidantes/química , Flavonoides/química , Juglans/química , Extratos Vegetais/química , Polifenóis/química
7.
J Fungi (Basel) ; 8(5)2022 May 23.
Artigo em Inglês | MEDLINE | ID: mdl-35628800

RESUMO

The demand and interest in mushrooms, both cultivated and wild, has increased among consumers in recent years due to a better understanding of the benefits of this food. However, the ability of wild edible mushrooms to accumulate essential and toxic elements is well documented. In this study, a total of eight metallic elements and metalloids (chromium (Cr), arsenic (As), cadmium (Cd), mercury (Hg), lead (Pb), copper (Cu), zinc (Zn), and selenium (Se)) were determined by ICP-MS in five wild edible mushroom species (Agaricus silvicola, Amanita caesarea, Boletus aereus, Boletus edulis, and Russula cyanoxantha) collected in southern Spain and northern Morocco. Overall, Zn was found to be the predominant element among the studied species, followed by Cu and Se. The multivariate analysis suggested that considerable differences exist in the uptake of the essential and toxic elements determined, linked to species-intrinsic factors. Furthermore, the highest Estimated Daily Intake of Metals (EDIM) values obtained were observed for Zn. The Health Risk Index (HRI) assessment for all the mushroom species studied showed a Hg-related cause of concern due to the frequent consumption of around 300 g of fresh mushrooms per day during the mushrooming season.

8.
Antioxidants (Basel) ; 11(5)2022 Apr 26.
Artigo em Inglês | MEDLINE | ID: mdl-35624711

RESUMO

Despite the excellent beneficial properties that anthocyanins and total phenolic compounds give to the red onion bulbs, few articles have investigated modern extraction techniques or experimental designs in this field. For this reason, the present study proposes the development and optimization of alternative methods for the extraction of these compounds based on microwave-assisted extraction and the Box-Behnken experiment design. The optimal values for the extraction of total anthocyanins have been established at 62% methanol composition as a solvent, pH 2, 56 °C temperature, and 0.2:13 g:mL sample-solvent ratio. Regarding the extraction of total phenolic compounds, the optimal conditions have been established at 100% pure methanol as a solvent with pH 2, 57 °C temperature, and 0.2:8.8 g:mL sample-solvent ratio. Short extraction times (min), good recoveries (mg of bioactive compound g-1 of dry onion), and high repeatability and intermediate precision (coefficient of variation (%)) have been confirmed for both methods. Regarding total anthocyanins, the following results have been obtained: 2 min, 2.64 ± 0.093 mg of total anthocyanins g-1 of dry onion, and 2.51% and 3.12% for precision. Regarding phenolic compounds, the following results have been obtained: 15 min, 7.95 ± 0.084 mg of total phenolic compound g-1 of dry onion, and 3.62% and 4.56% for precision. Comparing these results with those of other authors and with those obtained in a previous study of ultrasound-assisted extraction, it can be confirmed that microwave-assisted extraction is a quantitative, repeatable, and very promising method for the extraction of phenolic compounds and anthocyanins, which offers similar and even superior results with little solvent expense, time, and costs.

9.
Antioxidants (Basel) ; 10(11)2021 Nov 03.
Artigo em Inglês | MEDLINE | ID: mdl-34829626

RESUMO

Allium cepa L. is one of the most abundant vegetable crops worldwide. In addition to its versatile culinary uses, onion also exhibits quite interesting medicinal uses. Bulbs have a high content of bioactive compounds that are beneficial for human health. This study intends to develop and optimize two appropriate ultrasound-assisted methods for the extraction of the phenolic compounds and anthocyanins present in red onion. A response surface methodology was employed and, specifically, a Box-Behnken design, for the optimization of the methods. The optimal conditions for the extraction of the phenolic compounds were the follows: 53% MeOH as solvent, pH 2.6, 60 °C temperature, 30.1% amplitude, 0.43 s cycle, and 0.2:11 g sample/mL solvent ratio. On the other hand, the optimal conditions for the anthocyanins were as follows: 57% MeOH as solvent, pH 2, 60 °C temperature, 90% amplitude, 0.64 s cycle, and 0.2:15 g sample/mL solvent ratio. Both methods presented high repeatability and intermediate precision, as well as short extraction times with good recovery yields. These results illustrate that the use of ultrasound-assisted extraction, when properly optimized, is suitable for the extraction and quantification of the compounds of interest to determine and improve the quality of the raw material and its subproducts for consumers.

10.
Pharmaceuticals (Basel) ; 14(4)2021 Apr 01.
Artigo em Inglês | MEDLINE | ID: mdl-33915768

RESUMO

Onion, one of the most consumed vegetables in the world, is also known to contain high levels of antioxidant compounds, with protective effects against different degenerative pathologies. Specifically, onion is rich in flavonols, mainly quercetin derivatives, which are compounds with high antioxidant and free radical scavenging power. For this reason, it is of the utmost importance to count on optimal analytical methods that allow for the determination and quantification of these compounds of interest. A rapid ultra-high performance liquid chromatography (UHPLC)-photo-diode array (PDA) method for the separation of the major flavonols in onions was developed using a Box-Behnken design in conjunction with multiresponse optimization on the basis of the desirability function. The conditions that provided a successful separation were 9.9% and 53.2% of phase B at the beginning and at the end of the gradient, respectively; 55 °C column working temperature; and 0.6 mL min-1 flow rate. The complete separation was achieved in less than 2.7 min with excellent chromatographic characteristics. The method was validated, and its high precision, low detection and quantification limits, good linearity, and robustness were confirmed. The correct applicability of the method improves the analysis of the raw material, increasing the quality of onions and its subproducts in terms of bioactive compounds and functional characteristics for consumers.

11.
Food Chem ; 356: 129688, 2021 Sep 15.
Artigo em Inglês | MEDLINE | ID: mdl-33812187

RESUMO

Capsaicinoids and capsinoids compounds have been a focus of special attention for their health benefits. An effective and rapid Ultra-High-Performance Liquid Chromatography (UHPLC-PDA) method has been developed and validated for the simultaneous separation and quantitative determination of the major capsaicinoids and capsinoids present in peppers. The separation of all the compounds of interest was achieved in less than 2 min by means of an ACQUITY UPLC BEH rp-C18 column (100 mm × 2.1 mm i.d., 1.7 µm particle size). The variables that have been optimized are the mobile phase (water as solvent A and acetonitrile as solvent B, both acidified by adding 0.1% acetic acid), separation gradient, column temperature (35-70 °C), flow rate (0.6-0.95 mL min-1), and injection volume (2.5-3.5 µL). The evaluation of the chromatographic performance revealed excellent resolution, retention factor, and selectivity. The method was satisfactorily validated in terms of linearity, detection and quantification limits, precision, and robustness.


Assuntos
Capsaicina/análogos & derivados , Capsaicina/análise , Capsicum/química , Cromatografia Líquida de Alta Pressão/métodos , Capsicum/metabolismo , Limite de Detecção , Espectrometria de Massas/métodos , Reprodutibilidade dos Testes , Temperatura
12.
Antioxidants (Basel) ; 10(2)2021 Feb 10.
Artigo em Inglês | MEDLINE | ID: mdl-33578861

RESUMO

The onion is one of the most cultivated and consumed vegetables, and is a very valuable source of antioxidant substances. Every onion variety is rich in flavonols-mainly quercetin derivatives which makes onions the main dietary source of these compounds. This study intends to develop an ultrasound-assisted extraction method (UAE), an economical, green, and efficient technique, that allows us to determine the quality of onion extracts in terms of flavonol composition and antioxidant activity. For this purpose, an ultrasound-assisted extraction method has been optimized to obtain extracts with a high amount of flavonols, as well as with a high antioxidant activity, not only separately using a Box-Behnken design, but also simultaneously, based on multi-response optimization. Multiple response optimization has not only demonstrated an efficacy level similar to that of the individual ones, but it also represents a considerable reduction in terms of cost, time and work. The optimal conditions for simultaneous extractions were determined as follows: 76.8% methanol as an extraction solvent at pH 2 and 58.5 °C temperature, 85% amplitude, 0.9 s cycle, and 0.2:13 g:mL sample mass/solvent volume ratio. Furthermore, the developed method exhibited a high precision level and great recoveries in a rather short extraction time (2 min). These results, together with the development of a fast and simple UHPLC analysis method, lead us to consider the developed UAE method as a suitable technique for the extraction of bioactive compounds from onion matrices.

13.
Food Chem ; 334: 127569, 2021 Jan 01.
Artigo em Inglês | MEDLINE | ID: mdl-32707360

RESUMO

Grapes are a great source of phenolic compounds, which have excellent antioxidant properties. Efficient analytical methods are necessary to selectively and precisely determine these compounds content in grapes. In this study, a reverse-phase ultra-high performance liquid chromatography (UHPLC) method with fluorescence and photodiode array detection has been developed to determine and quantify 27 of the main phenolic compounds present in grapes. An ACQUITY UPLC® BEH C18 (50 mm × 2.1 mm i.d., 1.7 mm particle size) column was employed. A gradient method was developed and column temperature (25-55 °C), as well as flow rate (0.6-0.75 mL min-1), were optimized. The optimum conditions allowed the separation of all the compounds in less than 9 min. The method was validated and demonstrated excellent detection and quantification limits, precision, and selectivity. Finally, several grape varieties were studied in order to demonstrate the applicability of the method to the analysis of real matrix samples.


Assuntos
Cromatografia Líquida de Alta Pressão/métodos , Flavonoides/análise , Frutas/química , Vitis/química , Flavonoides/isolamento & purificação , Limite de Detecção , Fenóis/análise , Fenóis/isolamento & purificação , Sensibilidade e Especificidade
14.
Foods ; 9(12)2020 Nov 28.
Artigo em Inglês | MEDLINE | ID: mdl-33260750

RESUMO

In recent years, consumers' preference for fruits such as blueberry has increased noticeably. This fact is probably related to their bioactive components such as anthocyanins, phenolic compounds, vitamins, minerals, and tannins that have been found in blueberries by the latest research studies. Both total anthocyanins (TA) and total phenolic compounds (TPC) are known for their multiple beneficial effects on our health, due to their anti-inflammatory, anti-oxidant, and anti-cancer properties. This is the reason why the development of new methodologies for the quality control analysis of raw materials or derived products from blueberry has a great relevance. Two ultrasound-assisted extraction methods (UAE) have been optimized for the quantification of TA and TPC in blueberry samples. The six variables to be optimized were: solvent composition, temperature, amplitude, cycle, extraction solvent pH, and sample/solvent ratio using response surface methodology. The optimized methods have proven to be suitable for the extraction of the TPC and TA with good precision (repeatability and intermediate precision) (coefficient of variation (CV) < 5%) and potentially for application in commercial samples. This fact, together with the multiple advantages of UAE, makes these methods a good alternative to be used in quality control analysis by both industries and laboratories.

15.
Plants (Basel) ; 9(9)2020 Sep 17.
Artigo em Inglês | MEDLINE | ID: mdl-32957596

RESUMO

Peppers are fruits with wide genetic variability and multiple ways of being consumed that hold a relevant position in the human diet. Nowadays, consumers are interested in new gastronomic experiences provided by pepper cultivars that present new shapes, colors, and flavors while preserving their bioactive compounds, such as their capsaicinoids and capsinoids. However, numerous changes take place during their development that may alter their biological properties. Therefore, this work evaluates the capsaicinoid and capsiate contents in two traditional varieties of ornamental peppers ("Filius Blue" and "Filius Green'") during fruit maturation. The aim is to determine the ideal harvesting moment depending on the farmer's objective (e.g., achieving a specific color, shape, or flavor; achieving the maximum concentrations of bioactive compounds). The capsaicinoid contents followed different patterns in the two varieties analyzed. The "Filius Blue" variety exhibited increasing concentrations of capsaicinoids up to the 41st day post-anthesis (dpa), from which point on this trend was reversed. The concentrations in the "Filius Green" variety increased and decreased several times, reaching maximum concentrations on the 69th dpa. Regarding capsiate contents, both varieties varied in the same way, reaching maximum concentrations on the 34th dpa and then decreasing.

16.
Plants (Basel) ; 8(9)2019 Sep 05.
Artigo em Inglês | MEDLINE | ID: mdl-31491917

RESUMO

Myrtus communis L. is an evergreen shrub that produces berries with a high content in antioxidant compounds. Since these compounds have demonstrated a positive effect on human health, the interest on berries and their usages has increased. However, environmental conditions may affect the productivity of these species and consequently the quality of wild myrtle. Ecotypes from diverse geographical origins may result in significant variations in terms of bioactive compounds content as well as in chemical traits. For this reason, in this work ecotypes from two different localizations have been studied to determine if their differences in morphological and anthocyanins traits can be attributed to their origin and the environmental characteristics of these locations. For this, chemometric analyses such as Hierarchical Cluster Analysis and Principal Component Analysis, were employed. The results showed differences between the ecotypes depending on their location. In particular, myrtle berries from maritime zones present greater fruit size and amount of bioactive compounds, which means an improvement in the quality of the final product based on this raw material. It can be concluded that both morphological and anthocyanins traits are related to the location of the ecotype and allow selecting the best ecotype for the required applications.

17.
Talanta ; 204: 57-62, 2019 Nov 01.
Artigo em Inglês | MEDLINE | ID: mdl-31357336

RESUMO

In this work, a method for the determination of phosphorus in walnuts has been developed due to the fact that there is no specific method for this purpose. A closed-vessel microwave-assisted digestion of the samples was optimized and a modified molybdenum blue spectrophotometric method was carried out with excellent precision and selectivity. To differentiate assimilable and non-assimilable phosphorus, an easy extraction procedure using 1 M NH4Cl was used. FTIR spectra ensured that the phytate extraction was successful. A sampling of thirteen different walnuts available to consumers from different crops and geographical origin was performed. Comparative statistical tools to differentiate walnuts were also carried out. Significant differences based on total content of phosphorus were obtained. Finally, a correlation study between total phosphorus concentration and the non-assimilable fraction showed a non-linear relationship (R2 = 0.435). Therefore, in relation to consumer health the total phosphorus determination must be complemented with information about assimilable phosphorus.


Assuntos
Juglans/química , Nozes/química , Fósforo/análise , Molibdênio/química , Extração em Fase Sólida/métodos , Espectroscopia de Infravermelho com Transformada de Fourier/métodos
18.
Talanta ; 203: 235-241, 2019 Oct 01.
Artigo em Inglês | MEDLINE | ID: mdl-31202332

RESUMO

According to European Union regulations, honey is a pure product and adding to or removing from it any kind of substance is illegal. Nevertheless, its adulteration by adding inexpensive and artificial adulterants is a common practice. This paper deals with the use of visible and near-infrared spectroscopy (Vis-NIRS) combined with chemometric tools as a screening technique for the identification and quantification of different types of adulterants (inverted sugar, rice syrup, brown cane sugar and fructose syrup) added to high-quality honey (Granada Protected Designation of Origin, Spain) at different levels (5%-50%). A complete discrimination between non-adulterated and adulterated samples was achieved. A general regression model to quantify the adulteration levels was developed as well as specific models for each adulterant. The coefficients of determination were higher than 0.96 for all the models. These results demonstrate the capacity of Vis-NIRS combined with chemometric tools for honey quality control.


Assuntos
Contaminação de Alimentos/análise , Mel/análise , Frutose/análise , Glucose/análise , Análise Multivariada , Oryza/química , Saccharum/química , Espectroscopia de Luz Próxima ao Infravermelho/métodos , Sacarose/análise
19.
Sensors (Basel) ; 19(7)2019 Apr 04.
Artigo em Inglês | MEDLINE | ID: mdl-30987373

RESUMO

Nowadays, adulteration of honey is a frequent fraud that is sometimes motivated by the high price of this product in comparison with other sweeteners. Food adulteration is considered a deception to consumers that may have an important impact on people's health. For this reason, it is important to develop fast, cheap, reliable and easy to use analytical methods for food control. In the present research, a novel method based on headspace-ion mobility spectrometry (HS-IMS) for the detection of adulterated honey by adding high fructose corn syrup (HFCS) has been developed. A Box-Behnken design combined with a response surface method have been used to optimize a procedure to detect adulterated honey. Intermediate precision and repeatability studies have been carried out and coefficients of variance of 4.90% and 4.27%, respectively, have been obtained. The developed method was then tested to detect adulterated honey. For that purpose, pure honey samples were adulterated with HFCS at different percentages (10-50%). Hierarchical cluster analysis (HCA) and principal component analysis (PCA) showed a tendency of the honey samples to be classified according to the level of adulteration. Nevertheless, a perfect classification was not achieved. On the contrary, a full classification (100%) of all the honey samples was performed by linear discriminant analysis (LDA). This is the first time the technique of HS-IMS has been applied for the determination of adulterated honey with HFCS in an automatic way.

20.
Molecules ; 24(5)2019 Mar 02.
Artigo em Inglês | MEDLINE | ID: mdl-30832328

RESUMO

The bioactive compounds in myrtle berries, such as phenolic compounds and anthocyanins, have shown a potentially positive effect on human health. Efficient extraction methods are to be used to obtain maximum amounts of such beneficial compounds from myrtle. For that reason, this study evaluates the effectiveness of a rapid ultrasound-assisted method (UAE) to extract anthocyanins and phenolic compounds from myrtle berries. The influence of solvent composition, as well as pH, temperature, ultrasound amplitude, cycle and solvent-sample ratio on the total phenolic compounds and anthocyanins content in the extracts obtained were evaluated. The response variables were optimized by means of a Box-Behnken design. It was found that the double interaction of the methanol composition and the cycle, the interaction between methanol composition and temperature, and the interaction between the cycle and solvent-sample ratio were the most influential variables on the extraction of total phenolic compounds (92.8% methanol in water, 0.2 s of cycle, 60 °C and 10:0.5 mL:g). The methanol composition and the interaction between methanol composition and pH were the most influential variables on the extraction of anthocyanins (74.1% methanol in water at pH 7). The methods that have been developed presented high repeatability and intermediate precision (RSD < 5%) and the bioactive compounds show a high recovery with short extraction times. Both methods were used to analyze the composition of the bioactive compounds in myrtle berries collected from different locations in the province of Cadiz (Spain). The results obtained by UAE were compared to those achieved in a previous study where microwave-assisted extraction (MAE) methods were employed. Similar extraction yields were obtained for phenolic compounds and anthocyanins by MAE and UAE under optimal conditions. However, UAE presents the advantage of using milder conditions for the extraction of anthocyanins from myrtle, which makes of this a more suitable method for the extraction of these degradable compounds.


Assuntos
Antocianinas/química , Myrtus/química , Fenóis/química , Extratos Vegetais/química , Antocianinas/isolamento & purificação , Antioxidantes/química , Antioxidantes/isolamento & purificação , Frutas/química , Humanos , Fenóis/isolamento & purificação , Folhas de Planta/química , Solventes/química , Espanha , Ondas Ultrassônicas
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