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1.
Medicine (Baltimore) ; 100(35): e26878, 2021 Sep 03.
Artigo em Inglês | MEDLINE | ID: mdl-34477121

RESUMO

ABSTRACT: Many free radicles are implicated to activate a number of oncogenic signaling, cause damage to deoxyribonucleic acid and tumor suppressor genes, or promote expression of proto-oncogenes. Reduced level of antioxidants and increases oxidative stress markers are associated with the development of various types of cancer.This prospective study included 60 women who were grouped into equal groups. Patients group included 30 breast cancer women and control group consisting of 30 apparently healthy women. Both groups were compared regarding the serum levels of antioxidants biomarkers (vitamin C, ceruloplasmin, glutathione) and oxidative stress biomarkers, malondialdehyde (MDA), peroxynitrite, and gamma-glutamyl transferase.In regard to the antioxidant biomarkers, there was a significant difference between the patients and the controls regarding the levels of serum ceruloplasmin and glutathione, (P values .000) for each while vitamin C showed no significant correlation (P value .053), while regarding oxidative stress biomarkers, the correlation was significant for both peroxynitrite and MDA (P value .000 and .001) respectively, and not significant for gamma-glutamyl transferase (P value 1.00).Reduced level both ceruloplasmin and glutathione is seen in patients with breast cancer while vitamin C is not associated. Elevated levels of both peroxynitrite and MDA is seen in patients with breast cancer which may be used as serum markers for the early detection of breast cancer.


Assuntos
Antioxidantes/análise , Neoplasias da Mama/tratamento farmacológico , Adulto , Antioxidantes/uso terapêutico , Estudos de Casos e Controles , Correlação de Dados , Feminino , Humanos , Pessoa de Meia-Idade , Estresse Oxidativo , Estudos Prospectivos
2.
Molecules ; 26(16)2021 Aug 04.
Artigo em Inglês | MEDLINE | ID: mdl-34443313

RESUMO

Nowadays, products of natural origin with health-promoting properties are increasingly more common. Research shows that fruit vinegars can be a source of compounds with antioxidant activity. Research on the total antioxidant capacity, total phenolic content, and antimicrobial properties against Staphylococcus aureus, Escherichia coli, and Candida albicans of grape vinegars were conducted. Moreover, gas chromatography was used to measure acetic acid content in the vinegars. The research material consisted of vinegars produced from five different grape varieties. For each variety, two variants were prepared: with and without the addition of sugar in the fermentation process. The highest antimicrobial activity against all micro-organisms was observed in vinegar produced from Solaris grapes with added sugar. The highest polyphenol content was observed in vinegar produced from the Prior grape variety with added sugar and the highest total antioxidant capacity is the Johanniter grape variety with added sugar. The vinegars examined in this study differed, depending on grape variety, in terms of antimicrobial properties, antioxidant capacity, total phenolic content, as well as acetic acid content. Sugar addition caused significant differences in the antioxidant capacity of vinegar samples.


Assuntos
Ácido Acético/farmacologia , Anti-Infecciosos/farmacologia , Antioxidantes/análise , Antioxidantes/farmacologia , Fermentação , Vitis/química , Cromanos/metabolismo , Concentração de Íons de Hidrogênio , Testes de Sensibilidade Microbiana , Polônia , Polifenóis/análise
3.
Molecules ; 26(16)2021 Aug 06.
Artigo em Inglês | MEDLINE | ID: mdl-34443362

RESUMO

The polyphenol content of tea depends on the growing region, harvest date, the production process used, and the brewing parameters. In this study, research was undertaken that included an analysis of the influence of the brewing process parameters on the content of total polyphenols (Folin-Ciocalteu), epigallocatechin gallate (HPLC), and antioxidant activity (against DPPH radicals) of fresh tea shrub leaves grown from Taiwan and of teas obtained from them (oolong, green in bags, and green loose from the spring and autumn harvest). The antioxidant potential was determined in the methanol and aqueous extracts, as well as in infusions that were obtained by using water at 65 or 100 °C and infusing the tea for 5 or 10 min. The highest content of total polyphenols and epigallocatechin gallate was found in green tea extracts from the spring harvest. However, in the case of infusions, the highest content of these compounds was found in green tea in bags. Steaming at 100 °C for 10 min, turned out to be the most favourable condition for the extraction. Oolong tea, brewed at 100 °C for 5 min was characterised by the highest antioxidant activity against stable DPPH radicals.


Assuntos
Antioxidantes/análise , Camellia sinensis/química , Manipulação de Alimentos/métodos , Folhas de Planta/química , Temperatura , Fatores de Tempo , Água/química
4.
Int J Mol Sci ; 22(15)2021 Jul 25.
Artigo em Inglês | MEDLINE | ID: mdl-34360688

RESUMO

Plant response to osmotic stress is a complex issue and includes a wide range of physiological and biochemical processes. Extensive studies of known cultivars and their reaction to drought or salinity stress are very important for future breeding of new and tolerant cultivars. Our study focused on the antioxidant activity, accumulations of osmotica, and the content of abscisic acid in apple (cv. "Malinové holovouské", "Fragrance", "Rubinstep", "Idared", "Car Alexander") and cherry (cv. "Regina", "Napoleonova", "Kastánka", "Sunburst", "P-HL-C") cultivated in vitro on media containing different levels of polyethylene glycol PEG-6000. Our results indicated that the studied genotypes responded differently to osmotic stress manifested as reduction in the leaf relative water content (RWC) and increment in the activities of antioxidant enzymes, proline, sugars, and abscisic acid content. Overall, cherry cultivars showed a smaller decrease in percentage RWC and enzymatic activities, but enhanced proline content compared to the apple plants cultivars. Cultivars "Rubinstep", "Napoleonova", and "Kastánka" exhibited higher antioxidant capacity and accumulation of osmoprotectants like proline and sorbitol that can be associated with the drought-tolerance system.


Assuntos
Ácido Abscísico/análise , Antioxidantes/análise , Pressão Osmótica , Prolina/análise , Estresse Fisiológico , Açúcares/análise , Malus/química , Malus/metabolismo , Malus/fisiologia , Prolina/metabolismo , Prunus avium/química , Prunus avium/metabolismo , Prunus avium/fisiologia , Açúcares/metabolismo
5.
Molecules ; 26(15)2021 Jul 29.
Artigo em Inglês | MEDLINE | ID: mdl-34361748

RESUMO

The aim of this study was to determine the effects that the type of impregnating solution and drying method (freeze drying (FD) and vacuum drying (VD) at 45 °C and convective drying (CD) at 50, 60, and 70 °C) had on the physicochemical and quality properties of courgettes. Courgette slices were vacuum-impregnated (6 kPa) in freshly squeezed onion, kale, and onion and kale (50:50) juices with 3% NaCl solution (N). The application of vacuum impregnation (VI) with impregnating solutions from freshly squeezed onions and kale had a beneficial effect on the bioactive values of courgette. The highest contents of quercetin (41.84 µg/g d.m.) and carotenoids (276.04 µg/g d.m.) were found in courgette impregnated with onion juice after freeze drying. The highest values of lutein and zeaxanthin (216.42 µg/g d.m.) were recorded for courgette impregnated with kale juice and convective dried. By analysing the kinetics of convective drying, the best matching of the logistic model was found. Increasing the drying process temperature from 50 to 70 °C reduced the drying time from 15% to 36%, depending on the type of impregnating solution used. Water activity < 0.6 was recorded for courgette dried by freezing, vacuum, and convection at 60 and 70 °C. Conclusions: The vacuum impregnation process and the impregnation solutions from freshly squeezed vegetables can be used to develop new snacks with high levels of bioactive compounds. The FD method is the most appropriate considering both the bioactive compounds content and the obtained colour and water activity.


Assuntos
Antioxidantes/análise , Cucurbitaceae/química , Dessecação/métodos , Tecnologia de Alimentos/métodos , Liofilização/métodos , Brassica/química , Carotenoides/análise , Dessecação/instrumentação , Liofilização/instrumentação , Humanos , Cinética , Luteína/análise , Valor Nutritivo , Cebolas/química , Quercetina/análise , Lanches , Vácuo , Zeaxantinas/análise
6.
Molecules ; 26(15)2021 Jul 21.
Artigo em Inglês | MEDLINE | ID: mdl-34361551

RESUMO

Honey is a well-known natural sweetener and is rich in natural antioxidants that prevent the occurrence of oxidative stress, which is responsible for many human diseases. Some of the biochemical compounds in honey that contribute to this property are vitamins and phenolic compounds such as phenolic acids and flavonoids. However, the extent to which these molecules contribute towards the antioxidant capacity in vitro is inconsistently reported, especially with the different analytical methods used, as well as other extrinsic factors that influence these molecules' availability. Therefore, by reviewing recently published works correlating the vitamin, total phenolic, and flavonoid content in honey with its antioxidant activities in vitro, this paper will establish a relationship between these parameters. Based on the literature, vitamins do not contribute to honey's antioxidant capacity; however, the content of phenolic acids and flavonoids has an impact on honey's antioxidant activity.


Assuntos
Antioxidantes/análise , Flavonoides/análise , Análise de Alimentos , Mel/análise , Fenóis/análise , Vitaminas/análise , Humanos
7.
Molecules ; 26(15)2021 Jul 21.
Artigo em Inglês | MEDLINE | ID: mdl-34361554

RESUMO

The objective of this study was to investigate the use of citrus fiber as a carrier of blackberry juice polyphenols. For that purpose, freeze-dried complexes with blackberry juice and different amounts of citrus fiber (1%, 2% and 4%) were prepared. Complexes were evaluated spectrophotometrically for total polyphenols, proanthocyanidins and antioxidant activity. Analyses of individual polyphenols were performed using high-performance liquid chromatography. IR spectra were recorded to confirm encapsulation. All analyses were performed after preparation and after eight months of storage, in order to examine the stability of formed complexes. The obtained results indicated that increasing the amount of fiber led to a decrease in the concentration of polyphenols and the antioxidant activity of complexes. Cyanidin 3-glucoside was the prevalent anthocyanin in complexes (138.32-246.45 mg/100 g), while cyanidin 3-dioxalylglucoside was present at lower concentrations (22.19-31.45 mg/100 g). The other identified and quantified polyphenols were hesperidin (from citrus fiber), ellagic acid and quercetin (1317.59-1571.65 mg/100 g, 31.94-50.11 mg/100 g and 20.11-33.77 mg/100 g, respectively). Degradation of polyphenols occurred during storage. Results obtained in this study confirmed that citrus fiber could be used for the formulation of novel bioactive additives. Such additives could enhance the antioxidant potential of products to which they are added, such as baked goods, dairy, or fruit products.


Assuntos
Antioxidantes/análise , Citrus/química , Fibras na Dieta/análise , Sucos de Frutas e Vegetais/análise , Polifenóis/análise , Rubus/química
8.
Molecules ; 26(16)2021 Aug 11.
Artigo em Inglês | MEDLINE | ID: mdl-34443462

RESUMO

Ajuga bracteosa Wall. ex Benth. is an endangered medicinal herb traditionally used against different ailments. The present study aimed to create new insight into the fundamental mechanisms of genetic transformation and the biological activities of this plant. We transformed the A. bracteosa plant with rol genes of Agrobacterium rhizogenes and raised the regenerants from the hairy roots. These transgenic regenerants were screened for in vitro antioxidant activities, a range of in vivo assays, elemental analysis, polyphenol content, and different phytochemicals found through HPLC. Among 18 polyphenolic standards, kaempferol was most abundant in all transgenic lines. Furthermore, transgenic line 3 (ABRL3) showed maximum phenolics and flavonoids content among all tested plant extracts. ABRL3 also demonstrated the highest total antioxidant capacity (8.16 ± 1 µg AAE/mg), total reducing power, (6.60 ± 1.17 µg AAE/mg), DPPH activity (IC50 = 59.5 ± 0.8 µg/mL), hydroxyl ion scavenging (IC50 = 122.5 ± 0.90 µg/mL), and iron-chelating power (IC50 = 154.8 ± 2 µg/mL). Moreover, transformed plant extracts produced significant analgesic, anti-inflammatory, anticoagulant, and antidepressant activities in BALB/c mice models. In conclusion, transgenic regenerants of A. bracteosa pose better antioxidant and pharmacological properties under the effect of rol genes as compared to wild-type plants.


Assuntos
Ajuga/química , Polifenóis/farmacologia , Regeneração , Analgésicos/farmacologia , Animais , Anti-Inflamatórios/farmacologia , Anticoagulantes/farmacologia , Antidepressivos/farmacologia , Antioxidantes/análise , Bioensaio , Compostos de Bifenilo/química , Cromatografia Líquida de Alta Pressão , Elementos Químicos , Flavonoides/análise , Sequestradores de Radicais Livres/química , Hidróxidos/química , Concentração Inibidora 50 , Quelantes de Ferro/farmacologia , Masculino , Camundongos Endogâmicos BALB C , Fenóis/análise , Picratos/química , Plantas Geneticamente Modificadas , Regeneração/efeitos dos fármacos
9.
Int J Mol Sci ; 22(15)2021 Jul 29.
Artigo em Inglês | MEDLINE | ID: mdl-34360936

RESUMO

Dietary consumption of fruits and vegetables is related to a risk reduction in a series of leading human diseases, probably due to the plants' antioxidant content. Plant-derived nanovesicles (PDNVs) have been recently receiving great attention regarding their natural ability to deliver several active biomolecules and antioxidants. To investigate the presence of active antioxidants in fruits, we preliminarily analyzed the differences between nanovesicles from either organic or conventional agriculture-derived fruits, at equal volumes, showing a higher yield of nanovesicles with a smaller size from organic agriculture-derived fruits as compared to conventional ones. PDNVs from organic agriculture also showed a higher antioxidant level compared to nanovesicles from conventional agriculture. Using the PDNVs from fruit mixes, we found comparable levels of Total Antioxidant Capacity, Ascorbic Acid, Catalase, Glutathione and Superoxide Dismutase 1. Finally, we exposed the nanovesicle mixes to either chemical or physical lytic treatments, with no evidence of effects on the number, size and antioxidant capacity of the treated nanovesicles, thus showing a marked resistance of PDNVs to external stimuli and a high capability to preserve their content. Our study provides for the first time a series of data supporting the use of plant-derived nanovesicles in human beings' daily supplementation, for both prevention and treatment of human diseases.


Assuntos
Antioxidantes/análise , Frutas/química , Agricultura Orgânica , Verduras/química , Dieta , Vesículas Extracelulares , Humanos
10.
Molecules ; 26(13)2021 Jun 29.
Artigo em Inglês | MEDLINE | ID: mdl-34209531

RESUMO

Sorghum is a major cereal food worldwide, and is considered a potential source of minerals and bioactive compounds. Its wide adaptive range may cause variations in its agronomic traits, antioxidant properties, and phytochemical content. This extensive study investigated variations in seed characteristics, antioxidant properties, and total phenolic (TPC) and flavonoid contents (TFC) of sorghum collected from different ecological regions of 15 countries. The antioxidant potential of the seed extracts of various sorghum accessions was determined using 1,1-diphenyl-2-picrylhydrazyl (DPPH) and 2,2'-azinobis 3-ethylbenzothiazoline-6-sulfonate (ABTS) radical scavenging assays. Significant variations in TPC were observed among the sorghum accessions. All 78 sorghum accessions used in this study exhibited significant variations in TFC, with the lowest and highest amount observed in accessions C465 and J542, respectively. DPPH scavenging potential of the seed extracts for all the accessions ranged from 11.91 ± 4.83 to 1343.90 ± 81.02 µg mL-1. The ABTS assay results were similar to those of DPPH but showed some differences in the accessions. Pearson's correlation analysis revealed a wide variation range in the correlation between antioxidant activity and TPC, as well as TFC, among the sorghum accessions. A wide diversity range was also recorded for the seed characteristics (1000-seed weight and seed germination rate). A dendrogram generated from UPGMA clustering, based on seed traits, antioxidant activity, TPC, and TFC was highly dispersed for these accessions. Variations among the accessions may provide useful information regarding the phytoconstituents, antioxidant properties, and phytochemical contents of sorghum and aid in designing breeding programs to obtain sorghum with improved agronomic traits and bioactive properties.


Assuntos
Antioxidantes , Flavonoides , Fenóis , Sementes/química , Sorghum/química , Antioxidantes/análise , Antioxidantes/química , Flavonoides/análise , Flavonoides/química , Fenóis/análise , Fenóis/química
11.
Molecules ; 26(12)2021 Jun 11.
Artigo em Inglês | MEDLINE | ID: mdl-34208409

RESUMO

Spider plant (Cleome gynandra L.) is an important leafy vegetable that grows naturally in many parts of the world. The leaves are highly nutritious and are used mainly for human consumption. The mineral content and phenolic compounds of 17 genotypes (local and exotic) of spider plant and four standards (swiss chard, jute mallow, cowpea, and pumpkin) were investigated. Leaf samples were harvested from plants raised at Thohoyandou, South Africa. Exotic genotypes were superior to local genotypes for most of the minerals. Swiss chard possessed significantly high levels of some minerals such as iron and manganese in comparison with exotic spider plant genotypes. The calcium content in the local ('MP-B-3-CG') and exotic ('GPS') genotypes was >30.0% and >60.0% higher than in swiss chard, respectively. Total phenolics among spider plant genotypes ranged from 9.86 to 12.21 mg GAE/g DW and were superior to pumpkin. In addition, the spider plant genotypes varied significantly in the antioxidant capacity as estimated by the 2,2 diphenyl-1-picrylhydrazyl method and ferric-reducing antioxidant power. The main flavonoid in the leaves of spider plant genotypes was quercetin-3-rutinoside. Crotonoside (glycoside) was detected in all the spider plant genotypes and swiss chard. A positive correlation was observed between total phenolic content and each of the three flavonoids. The PCA biplot associated exotic genotypes ('ML-SF-29', 'PS', 'TZ-1', and 'GPS') and local genotypes ('ML-3-KK', 'ML-13-SDM', and 'ML-12-TMP') with high Al, Fe, Zn, N, and TPC. Cluster analysis indicated high "distant groups" between exotic and local genotypes of spider plant. These results indicated that some of the local germplasm of spider plant was largely inferior to the exotic germplasm in terms of their mineral composition but contained considerable quantities of quercetin-3-rutinoside, particularly in the local genotypes 'MP-B-2-CG' and 'MP-B-1-CG'. There is a need for genetic improvement of the local germplasm in some of the minerals particularly to benefit the end-users.


Assuntos
Cleome/química , Flavonoides/análise , Minerais/análise , Fenóis/análise , Extratos Vegetais/análise , Antioxidantes/análise , Folhas de Planta/química , Sementes/química , África do Sul
12.
Molecules ; 26(12)2021 Jun 13.
Artigo em Inglês | MEDLINE | ID: mdl-34199199

RESUMO

Natural products have always enjoyed great popularity among consumers. Wild tea is an interesting alternative to tea from intensive plantations. The term "wild tea" is applied to many different varieties of tea, the most desirable and valued of which are native or indigenous tea plants. Special pro-health properties of wild tea are attributed to the natural conditions in which it grows. However, there are no complex studies that describe quality and health indicators of wild tea. The aim of this research was to evaluate the quality of wild and cultivated green tea from different regions of China: Wuzhishan, Baisha, Kunlushan, and Pu'Er. The assessment was carried out by verifying the concentration of selected chemical components in tea and relating it to the health risks they may pose, as well as to the nutritional requirements of adults. Wild tea was characterized by higher micronutrient concentration. The analyzed teas can constitute a valuable source of Mn in the diet. A higher concentration of nitrates and oxalates in cultivated tea can be associated with fertilizer use. The analyzed cultivated tea was a better source of antioxidants with a higher concentration of caffeine. There were no indications of health risks for wild or cultivated teas.


Assuntos
Antioxidantes/análise , Fertilizantes/análise , Oxalatos/análise , Extratos Vegetais/análise , Folhas de Planta/química , Polifenóis/química , Chá/química , China , Elementos Químicos , Humanos , Nitratos/análise , Controle de Qualidade
13.
BMC Neurol ; 21(1): 258, 2021 Jul 02.
Artigo em Inglês | MEDLINE | ID: mdl-34215195

RESUMO

BACKGROUND: Stroke is a major cause of mortality and morbidity. Also, free radicals and oxidative stress are deleterious factor in the stroke progression. We aimed to evaluate the association between oxidative stress markers and odds of having risk factor for stroke or developing stroke. METHODS: The present case-control study was conducted on 556 participants in Imam-Reza hospital, Tabriz, Iran. Subjects were divided into three group, including individuals with acute ischemic stroke, those who were at risk of stroke, and healthy controls. All enrolled participants except for controls underwent neurological examinations and brain magnetic resonance imaging (MRI). Stroke-related disability and stroke severity were evaluated by modified Rankin Scale (mRS) and National Institutes of Health Stroke Scale (NIHSS), respectively. Serum malondialdehyde (MDA) level and total antioxidant capacity (TAC) were measured within 48 h of the initiation of stroke. One-way ANOVA and Chi-square tests were used for comparing characteristics between groups. Multivariable logistic regression was implemented for odds of stroke based on MDA and TAC quartiles. Also, Spearman's correlation was utilized. RESULTS: Serum MDA, systolic and diastolic blood pressure, cholesterol, and triglyceride were significantly higher in the stroke group than controls. High levels of MDA were associated with increased development of stroke (P-value < 0.001), however TAC and MDA were not associated with having risk factors for stroke (P-value = 1.00 and 0.27, respectively). Also, TAC level was negatively associated with baseline (ρ = - 0.28; P-value = 0.04) and follow-up (ρ = - 0.31; P-value = 0.03) NIHSS scores. Moreover, MDA was correlated with mRS score at follow-up (ρ = - 0.26; P-value = 0.04). CONCLUSIONS: The balance between antioxidants and oxidants markers might reveal a new approach in this context. Further studies are warranted to identify the source of oxidative stress as well as cessation of the production of oxygen radicals in stroke.


Assuntos
AVC Isquêmico , Estresse Oxidativo/fisiologia , Antioxidantes/análise , Biomarcadores/sangue , Estudos de Casos e Controles , Humanos , AVC Isquêmico/sangue , AVC Isquêmico/diagnóstico , AVC Isquêmico/epidemiologia , Prognóstico , Fatores de Risco
14.
Molecules ; 26(13)2021 Jun 25.
Artigo em Inglês | MEDLINE | ID: mdl-34202027

RESUMO

At present, a wide variety of analytical methods is available to measure antioxidant capacity. However, this great diversity is not reflected in the analysis of meat and meat products, as there are a limited number of studies on determining this parameter in this complex food matrix. Despite this, and due to the interest in antioxidants that prevent oxidation reactions, the identification of antioxidants in meat and meat products is of special importance to the meat industry. For this reason, this review compiled the main antioxidant capacity assays employed in meat and meat products, to date, describing their foundations, and showing both their advantages and limitations. This review also looked at the different applications of antioxidant properties in meat and meat products. In this sense, the suitability of using these methodologies has been demonstrated in different investigations related to these foods.


Assuntos
Antioxidantes/análise , Análise de Alimentos , Produtos da Carne/análise , Humanos
15.
Molecules ; 26(12)2021 Jun 12.
Artigo em Inglês | MEDLINE | ID: mdl-34204744

RESUMO

The cambuci is a native Brazilian fruit from the Atlantic Forest biome. A soft and astringent pulp, a green color, and a sweet aroma are its main characteristics. Classical food quality attributes (fresh fruit mass, fruit height, diameters, total soluble solid, titratable acidity, and ratio) and the metabolic profile from ten accessions from three different locations were analyzed herein by analytical methods (refractometry and neutralization titration) and nuclear magnetic resonance spectroscopy. Concerning sugar content, sucrose was the predominant compound, with glucose and fructose alternating in second, depending on the accession. Citric acid was the most relevant acid, followed by shikimic and quinic acids in quite variable amounts. These three main acids vary in amounts for each accession. Ascorbic acid content emerges as an important quality attribute and makes this fruit nutritionally attractive, due to values comparable to those contained in citric fruits. The main amino acids identified in cambuci were glutamic acid individually or in comprising the tripeptide glutathione (glutamic acid, cysteine, glycine). The quality diversity of the evaluated accessions suggests the potentiality of cambuci use in future breeding programs.


Assuntos
Frutas/química , Frutas/metabolismo , Myrtaceae/metabolismo , Ácidos/metabolismo , Antioxidantes/análise , Ácido Ascórbico/análise , Brasil , Carboidratos/análise , Qualidade dos Alimentos , Frutose/metabolismo , Glucose/metabolismo , Metaboloma , Metabolômica/métodos , Floresta Úmida
16.
Molecules ; 26(12)2021 Jun 16.
Artigo em Inglês | MEDLINE | ID: mdl-34208702

RESUMO

Coffee is one of the most often consumed beverages almost all over the world. The multiplicity of beans, as well as the methods and parameters used to brew, encourages the optimization of the brewing process. The study aimed to analyze the effect of roasting beans, the brewing technique, and its parameters (time and water temperature) on antioxidant activity (determined using several in vitro methods), total polyphenols, flavonoids, and caffeine content. The infusions of unroasted and roasted Arabica beans from Brazil, Colombia, India, Peru, and Rwanda were analyzed. In general, infusions prepared from roasted beans had higher antioxidant activity and the content of above-mentioned compounds. The hot brew method was used to obtain infusions with a higher antioxidant activity, while the cold brew with higher caffeine content. The phenolic compound content in infusions prepared using both techniques depended on the roasting process. Moreover, the bean's origin, roasting process, and brewing technique had a significant effect on the tested properties, in contrary to brewing time and water temperature (below and above 90 °C), which had less impact. The results confirm the importance of coffee brewing optimization.


Assuntos
Café/química , Antioxidantes/análise , Bebidas , Compostos de Bifenilo/análise , Brasil , Cafeína/análise , Coffea/química , Colômbia , Índia , Peru , Fenóis/análise , Extratos Vegetais/química , Polifenóis/análise , Sementes/química , Temperatura , Fatores de Tempo , Água/química
17.
Molecules ; 26(14)2021 Jul 10.
Artigo em Inglês | MEDLINE | ID: mdl-34299472

RESUMO

The impact of the composition of natural deep eutectic solvents (NADES) and extraction conditions on the simultaneous extraction of hydrophilic ascorbic acid (AA), phlorotannins (TPhC), and lipophilic fucoxanthin (FX) from Fucus vesiculosus was investigated for the first time. In biological tests, the NADES extracts showed the promising ability to scavenge DPPH radicals. A positive correlation was observed between DPPH scavenging activity and AA, TPhC, and FX contents. We calculate the synergistic effect of antioxidants extracted by NADES from F. vesiculosus based on the mixture effect (ME). The addition of 30% water to the NADES and the prolongation of sonication time from 20 min up to 60 min were favorable for the ME. The ME for extracts with the NADES was increased by two folds (ME > 2). In contrast, conventional extraction by maceration with steering at 60 °C does not lead to the synergistic effect (ME = 1). It is notable that the NADES provides high stability and preserves the antioxidant activity of the extracts from F. vesiculosus during storage.


Assuntos
Antioxidantes/isolamento & purificação , Fucus/química , Compostos Fitoquímicos/isolamento & purificação , Extratos Vegetais/isolamento & purificação , Solventes/química , Antioxidantes/análise , Interações Hidrofóbicas e Hidrofílicas , Compostos Fitoquímicos/análise , Extratos Vegetais/análise
18.
Molecules ; 26(14)2021 Jul 07.
Artigo em Inglês | MEDLINE | ID: mdl-34299402

RESUMO

Prunus persica L. is one of the most important fruit crops in European production, after grapes, apples, oranges and watermelons. Most varieties are rich in secondary metabolites, showing antioxidant properties for human health. The purpose of this study was to develop a chemical analysis methodology, which involves the use of different analytical-instrumental techniques to deepen the knowledge related to the profile of metabolites present in selected cultivars of peaches and nectarines cultivated in the Mediterranean area (Southern Italy). The comparative study was conducted by choosing yellow-fleshed peaches (RomeStar, ZeeLady) and yellow-fleshed nectarines (Nectaross, Venus) from two geographical areas (Piana di Sibari and Piana di Metaponto), and by determining the chemical parameters for the flesh and skin that allow for identification of any distinctive varietal and/or geographical characteristics. A combined analytical and chemometric approach was used, trough rheological, thermogravimetric (TGA), chromatographic (HPLC-ESI-MS), spectroscopic (UV-Vis, ATR-FTIR, NMR) and spectrometric (ToF-SIMS) analysis. This approach allowed us to identify the characterizing parameters for the analysis of a plant matrix so that the developed methodology could define an easily exportable and extendable model for the characterization of other types of vegetable matrices.


Assuntos
Antioxidantes/análise , Frutas/classificação , Frutas/metabolismo , Cromatografia Gasosa-Espectrometria de Massas/instrumentação , Modelos Estatísticos , Prunus persica/classificação , Prunus persica/metabolismo , Antioxidantes/metabolismo , Geografia
19.
Molecules ; 26(14)2021 Jul 07.
Artigo em Inglês | MEDLINE | ID: mdl-34299420

RESUMO

A comparative study of volatile constituents, antioxidant activity, and molecular docking was conducted between essential oils from Mentha longifolia L., Mentha spicata L., and Origanum majorana L., widely cultivated in Madinah. The investigation of volatile oils extracted by hydrodistillation was performed using Gas Chromatography-Mass Spectrometry (GC-MS). A total number of 29, 42, and 29 components were identified in M. longifolia, M. spicata, and O. majorana representing, respectively, 95.91, 94.62, and 98.42, of the total oils. Pulegone (38.42%), 1,8-cineole (15.60%), menthone (13.20%), and isopulegone (9.81%) were the dominant compounds in M. longifolia oil; carvone (35.14%), limonene (27.11%), germacrene D (4.73%), and ß-caryophyllene (3.02%) were dominant in M. spicata oil; terpin-4-ol (42.47%), trans-sabinene hydrate (8.52%), γ-terpinene (7.90%), α-terpineol (7.38%), linalool (6.35%), α-terpinene (5.42%), and cis-sabinene hydrate (3.14%) were dominant in O. majorana oil. The antioxidant activity, assessed using DPPH free radical-scavenging and ABTS assays, was found to be the highest in O. majorana volatile oil, followed by M. spicata and M. longifolia, which is consistent with the differences in total phenolic content and volatile constituents identified in investigated oils. In the same context, molecular docking of the main identified volatiles on NADPH oxidase showed a higher binding affinity for cis-verbenyl acetate, followed by ß-elemene and linalool, compared to the control (dextromethorphan). These results prove significant antioxidant abilities of the investigated oils, which may be considered for further analyses concerning the control of oxidative stress, as well as for their use as possible antioxidant agents in the pharmaceutical industry.


Assuntos
Antioxidantes/farmacologia , Mentha/química , NADPH Oxidases/metabolismo , Óleos Voláteis/farmacologia , Origanum/química , Compostos Orgânicos Voláteis/farmacologia , Antioxidantes/análise , Simulação de Acoplamento Molecular , Óleos Voláteis/análise , Arábia Saudita , Compostos Orgânicos Voláteis/análise
20.
Molecules ; 26(13)2021 Jun 23.
Artigo em Inglês | MEDLINE | ID: mdl-34201524

RESUMO

Some agroforestry residues such as orange and olive tree pruning have been extensively evaluated for their valorization due to its high carbohydrates content. However, lignin-enriched residues generated during carbohydrates valorization are normally incinerated to produce energy. In order to find alternative high added-value applications for these lignins, a depth characterization of them is required. In this study, lignins isolated from the black liquors produced during soda/anthraquinone (soda/AQ) pulping of orange and olive tree pruning residues were analyzed by analytical standard methods and Fourier-transform infrared spectroscopy (FTIR), nuclear magnetic resonance (solid state 13C NMR and 2D NMR) and size exclusion chromatography (SEC). Thermal analysis (thermogravimetric analysis (TGA), differential scanning calorimetry (DSC)) and antioxidant capacity (Trolox equivalent antioxidant capacity) were also evaluated. Both lignins showed a high OH phenolic content as consequence of a wide breakdown of ß-aryl ether linkages. This extensive degradation yielded lignins with low molecular weights and polydispersity values. Moreover, both lignins exhibited an enrichment of syringyl units together with different native as well as soda/AQ lignin derived units. Based on these chemical properties, orange and olive lignins showed relatively high thermal stability and good antioxidant activities. These results make them potential additives to enhance the thermo-oxidation stability of synthetic polymers.


Assuntos
Antioxidantes/análise , Citrus sinensis/química , Lignina/química , Lignina/farmacologia , Olea/química , Fenóis/análise , Varredura Diferencial de Calorimetria , Cromatografia em Gel , Espectroscopia de Ressonância Magnética , Espectroscopia de Infravermelho com Transformada de Fourier , Termogravimetria
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