Your browser doesn't support javascript.
Mostrar: 20 | 50 | 100
Resultados 1 - 9 de 9
Filtrar
Mais filtros










Base de dados
Intervalo de ano de publicação
1.
Food Chem ; 295: 514-519, 2019 Oct 15.
Artigo em Inglês | MEDLINE | ID: mdl-31174790

RESUMO

Chayote, the fruit of Sechium edule (Jacq.) Swartz, is known for culinary applications and in traditional medicine. A great number of its health benefits have been related to its phenolic composition. However, literature concerning the characterization of phenolic compounds in chayote is scarce. Therefore, this work highlights new information about the composition of chayote. For that, different hydro-alcoholic mixtures (50-100% ethanol content) were used to recover phenolic compounds by ultrasound assisted extraction (UAE) and the platform HPLC-ESI-TOF-MS was employed to characterize these components in the fruit. Briefly, 26 compounds, classified as phenolic acids, flavonoids and other polar compounds were identified in the fruit. About the effect of ethanol ratio on phenolic extraction, 70% ethanol exhibited the best recovery of target compounds (188 ±â€¯2 mg/100 g fruit d.w.). Chayote is rich in flavones accounting for a 60.6% from the total compounds quantified and the major compound is diosmetin 7-O-rutinoside (23.8%).


Assuntos
Cucurbitaceae/química , Análise de Alimentos/métodos , Fenóis/análise , Cromatografia Líquida de Alta Pressão , Flavonoides/análise , Frutas/química , Extratos Vegetais/análise , Extratos Vegetais/química , Espectrometria de Massas por Ionização por Electrospray/métodos , Ultrassom/métodos
2.
Food Chem ; 269: 258-263, 2018 Dec 15.
Artigo em Inglês | MEDLINE | ID: mdl-30100433

RESUMO

Potato processing generates large amounts of by-products, which include potato peels and the outer layers of flesh, which contain phenolic compounds. The purpose of this study was to establish an extraction method for phenolic compounds from industrial potato by-products by using response surface methodology (RSM). Box-Behnken design (BBD) was performed to optimize the extraction conditions of phenolic compounds considering different extraction temperature, ratios of ethanol/water, time of extraction and sample/solvent ratio. The optimum extraction conditions were obtained with ethanol/water 55/45 (v/v) by ultrasound bath during 35 min at 35 °C and 1/10 sample/solvent ratio. The best conditions were applied to determine the phenolic content in five potato by-products. The analyses by HPLC-DAD-ESI-MS showed that chlorogenic acid accounted for a 49.3-61% of the total phenolic compounds. Positive Pearson correlations between HPLC data and antioxidant activity confirmed that the phenolic compounds had significant antioxidant properties.

3.
Anal Bioanal Chem ; 410(15): 3607-3619, 2018 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-29629503

RESUMO

Annona cherimola Mill. (cherimoya) has widely been used as food crop. The leaves of this tree possess several health benefits, which are, in general, attributed mainly to its bioactive composition. However, literature concerning a comprehensive characterization based on a combined approach, which consists of nuclear magnetic resonance (NMR) and high-performance liquid chromatography coupled with time-of-flight mass spectrometry (HPLC-TOF-MS), from these leaves is scarce. Thus, the aim of this work was to study the polar profile of full extracts of cherimoya leaves by using these tools. Thus, a total of 77 compounds have been characterized, 12 of which were identified by both techniques. Briefly, 23 compounds were classified as amino acids, organic acids, carbohydrates, cholines, phenolic acid derivatives, and flavonoids by NMR, while 66 metabolites were divided into sugars, amino acids, phenolic acids and derivatives, flavonoids, phenylpropanoids, and other polar compounds by HPLC-TOF-MS. It is worth mentioning that different solvent mixtures were tested and the total phenolic content in the extracts quantified (TPC via HPLC-TOF-MS). The tendency observed was EtOH/water 80/20 (v/v) (17.0 ± 0.2 mg TPC/g leaf dry weight (d.w.)) ≥ acetone/water 70/30 (v/v) (16.1 ± 0.7 mg TPC/g leaf d.w.) > EtOH/water 70/30 (v/v) (14.0 ± 0.3 mg TPC/g leaf d.w.) > acetone/water 80/20 (v/v) (13.5 ± 0.4 mg TPC/g leaf d.w.). Importantly, flavonoids derivatives were between 63 and 76% of the TPC in those extracts. Major compounds were sucrose, glucose (α and ß), and proline, and chlorogenic acid and rutin for NMR and HPLC-TOF-MS, respectively. Graphical abstract The combined use of LC-HRMS and NMR is a potential synergic combination for a comprehensive metabolite composition of cherimoya leaves.


Assuntos
Annona/química , Cromatografia Líquida de Alta Pressão/métodos , Espectroscopia de Ressonância Magnética/métodos , Extratos Vegetais/química , Folhas de Planta/química , Espectrometria de Massas por Ionização por Electrospray/métodos , Flavonoides/análise , Fenóis/análise
4.
Anal Bioanal Chem ; 410(15): 3547-3557, 2018 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-29423599

RESUMO

Myrtus communis L. (myrtle) is native to the Mediterranean region and Western Asia. Its leaves have demonstrated its potential effect towards different bioactivities like anti-diabetic, anti-diarrheic, anti-ulcer, anti-cancer, among others. These activities have been associated with its phenolic content. In this sense, the aim of this work has been to develop a new pressurized-liquid extraction procedure (PLE), by using a response surface methodology (RSM), to evaluate the phenolic composition from myrtle leaves by HPLC-DAD-TOF-MS. Previously, different solvents such as methanol, ethanol, and acetone/water mixtures were tested by using ultrasound-assisted extraction (UAE) in order to select the most suitable one. Subsequently, a Box-Behnken design (BBD) was performed according to the effect of ethanol/water ratio (50, 75, and 100% (v/v)), temperature (50, 125, and 200 °C), and extraction time (5, 18, and 30 min). The optimal conditions achieved with the established method were 71% ethanol/water, 137 °C, and 19 min. The analysis of the obtained extracts by HPLC-DAD-TOF-MS allowed the characterization of 15 new compounds in myrtle leaves. Finally, high amounts of gallic and ellagic acid were found in the optimized PLE extracts (3.31 ± 0.03 and 3.88 ± 0.09 mg/g leaf dry weight (d.w.), respectively), and PLE reported greater recovery of total phenolic compounds than UAE (30 ± 1 and 22.4 ± 0.6 mg/g leaf d.w., respectively).


Assuntos
Myrtus/química , Fenóis/análise , Folhas de Planta/química , Fracionamento Químico/métodos , Cromatografia Líquida de Alta Pressão/métodos , Espectrometria de Massas/métodos , Solventes , Sonicação/métodos
5.
Food Res Int ; 100(Pt 3): 423-434, 2017 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-28964365

RESUMO

Mango industry processing generates high quantities of mango by-products such as peels and seeds (35%-60% of the fruit). Indeed, it is known that mango and its by-products contain different families of bioactive compounds that possess several health benefits. Thus, the aim of this study has been the determination of different families of phenolic derivatives (free and bound phenolic compounds and alk(en)ylresorcinols (ARs)) in mango edible part and its by-products (peel, seed and seed husk) from three different cultivars. This is the first study that evaluates the phenolic compounds and ARs in the four fractions of mango of three different cultivars. Special attention has been paid to the determination of anthocyanins and ARs, because these families of compounds had not been studied in depth in mango. In fact, petunidin rutinoside-(p-coumaric acid) gallate was found in mango pulp, peel, seed and seed husk of the three cultivars and, it had never been described in mango before. It is also important to highlight that this is the first time that the identification and quantification of ARs have been performed in mango seed and seed husk; besides, four and five out of eleven alk(en)ylresorcinols detected in peel and pulp, respectively, were identified for the first time in these mango fractions. Furthermore, antioxidant activity was measured by ABTS and FRAP assays. Seed free and bound phenolic extracts showed the highest antioxidant capacity.

6.
Food Res Int ; 96: 64-71, 2017 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-28528109

RESUMO

Obesity is associated with a low-grade inflammatory status that affects vascular function. Previous studies have reported the beneficial effects of Psidium guajava L. (guava) on diabetes. Here we evaluate the how guava leaf extract at the dose of 5 mg/kg, affects vascular dysfunction in obese mice fed a high-fat diet for 7 weeks. Extract intake did not alter weight over time, although it reduced glycemia and insulin resistance, improving the serum lipid profile in obese mice. Additionally, guava leaf extract reversed the endothelial dysfunction found in obese mice in terms of endothelium- and NO (nitric oxide)-dependent vasodilatation induced by acetylcholine in aortic rings. In conclusion, the beneficial effects of guava leaf extract in obese mice were associated with improved vascular functions altered by obesity, probably due to its phenolic content.

7.
Int J Mol Sci ; 18(4)2017 Apr 24.
Artigo em Inglês | MEDLINE | ID: mdl-28441777

RESUMO

Today, there is increasing interest in discovering new bioactive compounds derived from ethnomedicine. Preparations of guava (Psidium guajava L.) leaves have traditionally been used to manage several diseases. The pharmacological research in vitro as well as in vivo has been widely used to demonstrate the potential of the extracts from the leaves for the co-treatment of different ailments with high prevalence worldwide, upholding the traditional medicine in cases such as diabetes mellitus, cardiovascular diseases, cancer, and parasitic infections. Moreover, the biological activity has been attributed to the bioactive composition of the leaves, to some specific phytochemical subclasses, or even to individual compounds. Phenolic compounds in guava leaves have been credited with regulating blood-glucose levels. Thus, the aim of the present review was to compile results from in vitro and in vivo studies carried out with guava leaves over the last decade, relating the effects to their clinical applications in order to focus further research for finding individual bioactive compounds. Some food applications (guava tea and supplementary feed for aquaculture) and some clinical, in vitro, and in vivo outcomes are also included.


Assuntos
Extratos Vegetais/química , Psidium/química , Animais , Doenças do Sistema Digestório/tratamento farmacológico , Doenças do Sistema Digestório/patologia , Humanos , Doenças Metabólicas/tratamento farmacológico , Doenças Metabólicas/patologia , Neoplasias/tratamento farmacológico , Neoplasias/patologia , Doenças Parasitárias/tratamento farmacológico , Doenças Parasitárias/patologia , Fenóis/química , Fenóis/farmacologia , Fenóis/uso terapêutico , Folhas de Planta/química , Folhas de Planta/metabolismo , Psidium/metabolismo
8.
J Pharm Biomed Anal ; 133: 1-7, 2017 Jan 30.
Artigo em Inglês | MEDLINE | ID: mdl-27780121

RESUMO

Due to the importance of the proanthocyanidins (PAs) bioactivity and its relationship with the PAs degree of polymerization (DP), an experimental design was carried out to establish the best extraction conditions in order to evaluate the proanthocyanidins content and their degree of polymerization in Psidium guajava leaves at different oxidation state. Optimal conditions achieved by response surface methodology were 50% acetone/water (v/v), 48°C, 30min, and 0% acetic acid (v/v). The highest DP has been found in the low oxidized state (DP 13 plus the polymers). Medium and high oxidized state leaves reported a DP 11 plus the polymers. The total amounts of proanthocyanidins (sum of PAs by HPLC-FLD-ESI-MS) decreased when oxidation state of leaves increased (15.8±0.4, 12.6±0.4, and 10.5±0.3mg/g leaf dry weight (d.w.) in low, medium and high oxidized state leaves, respectively). Guava leaves present an interesting source of low DP-PAs.


Assuntos
Folhas de Planta/química , Proantocianidinas/isolamento & purificação , Psidium/química , Modelos Estatísticos , Oxirredução , Polimerização , Ultrassom
9.
Int J Mol Sci ; 17(5)2016 May 11.
Artigo em Inglês | MEDLINE | ID: mdl-27187352

RESUMO

Psidium guajava L. is widely used like food and in folk medicine all around the world. Many studies have demonstrated that guava leaves have anti-hyperglycemic and anti-hyperlipidemic activities, among others, and that these activities belong mainly to phenolic compounds, although it is known that phenolic composition in guava tree varies throughout seasonal changes. Andalusia is one of the regions in Europe where guava is grown, thus, the aim of this work was to study the phenolic compounds present in Andalusian guava leaves at different oxidation states (low, medium, and high). The phenolic compounds in guava leaves were determined by HPLC-DAD-ESI-QTOF-MS. The results obtained by chromatographic analysis reported that guava leaves with low degree of oxidation had a higher content of flavonols, gallic, and ellagic derivatives compared to the other two guava leaf samples. Contrary, high oxidation state guava leaves reported the highest content of cyanidin-glucoside that was 2.6 and 15 times higher than guava leaves with medium and low oxidation state, respectively. The QTOF platform permitted the determination of several phenolic compounds with anti-diabetic properties and provided new information about guava leaf phenolic composition that could be useful for nutraceutical production.


Assuntos
Antioxidantes/análise , Hipoglicemiantes/análise , Fenóis/análise , Extratos Vegetais/química , Folhas de Planta/química , Psidium/química , Antioxidantes/farmacologia , Hipoglicemiantes/farmacologia , Fenóis/farmacologia
SELEÇÃO DE REFERÊNCIAS
DETALHE DA PESQUISA