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1.
PLoS One ; 15(6): e0234435, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-32574221

RESUMO

This study was designed to investigate the antioxidant properties of the extracts and subfractions of various polarities from Clerodendrum cyrtophyllum Turcz leaves and the related phenolic compound profiles. The ethyl acetate fraction (EAF) showed the most potent radical-scavenging activity for DPPH radicals, ABTS radicals, and superoxide anion (O2·-) radicals as well as the highest reducing power of the fractions tested; the n-butyl alcohol fraction (BAF) was the most effective in scavenging hydroxyl radical (OH·), and the dichloromethane fraction (DMF) exhibited the highest ferrous ion chelating activity. Twelve phenolic components were identified from the EAF of C. cyrtophyllum. Additionally, acteoside (1) was found to be a major component (0.803 g, 0.54%) and show DPPH and ABTS radical scavenging activities with IC50 values of 79.65±3.4 and 23.00±1.5 µg/ml, indicating it is principally responsible for the significant total antioxidant effect of C. cyrtophyllum. Our work offers a theoretical basis for further utilization of C. cyrtophyllum as a potential source of natural, green antioxidants derived from plants.


Assuntos
Antioxidantes/farmacologia , Clerodendrum/química , Glucosídeos/farmacologia , Fenóis/farmacologia , Extratos Vegetais/farmacologia , Antioxidantes/análise , Antioxidantes/isolamento & purificação , Glucosídeos/análise , Glucosídeos/isolamento & purificação , Radical Hidroxila/metabolismo , Fenóis/análise , Fenóis/isolamento & purificação , Extratos Vegetais/análise , Extratos Vegetais/isolamento & purificação , Folhas de Planta/química , Superóxidos/metabolismo
2.
Food Chem ; 331: 127305, 2020 Nov 30.
Artigo em Inglês | MEDLINE | ID: mdl-32593038

RESUMO

An ultra-high-performance liquid chromatography-triple quadrupole tandem mass spectrometry (UHPLC-QqQ-MS/MS) method was established and validated for the simultaneous quantification of eight cyanogenic glucosides (CNGs) in agri-food. The eight CNGs were linamarin, lotaustralin, linustatin, neolinustatin, taxiphyllin, amygdalin, dhurrin and prunasin. CNGs were extracted with aqueous methanol and cleaned via solid-phase extraction. Analytes were separated with a C18 column via gradient elution. MS/MS analysis was performed with electrospray ionisation in positive mode. Quantification was performed in multiple reaction monitoring mode. Satisfactory validation results were obtained in terms of linearity, sensitivity, precision and accuracy, matrix effect and stability. The method was applied in typical cyanogenic agri-food. CNGs in cassava, linseed, bamboo, sorghum, apricot, almond and lima bean were analyzed.


Assuntos
Cromatografia Líquida de Alta Pressão/métodos , Análise de Alimentos/métodos , Glucosídeos/análise , Glucosídeos/química , Nitrilos/química , Espectrometria de Massas em Tandem/métodos , Agricultura , Glucosídeos/isolamento & purificação , Extração em Fase Sólida , Fatores de Tempo
3.
Food Chem ; 326: 126960, 2020 Oct 01.
Artigo em Inglês | MEDLINE | ID: mdl-32413752

RESUMO

In this study, intermolecular copigmentation between five primary wine monoglucosidic anthocyanins (cyanidin-3-O-glucoside, peonidin-3-O-glucoside, delphinidin-3-O-glucoside, petunidin-3-O-glucoside, and malvidin-3-O-glucoside) and three common wine phenolics (gallic acid, (-)-epicatechin, and quercetin-3-O-glucoside) were investigated through experimental and theoretical methods, and the influence of substituent pattern of anthocyanin B ring was studied emphatically. Chromatic and thermodynamic analysis showed there were great differences among these different pigment-copigment systems. Spatial conformations of the 15 copigmentation complexes were obtained through theoretical calculation, and diverse π-π stacking modes were observed. These results indicated that the substituent pattern of anthocyanin B ring had significant impact on its affinity to copigments, and more, the structures of pigments and copigments determined the color expression and stability of copigmentation together.


Assuntos
Antocianinas/química , Fenóis/química , Vinho/análise , Antocianinas/análise , Cor , Glucosídeos/análise , Estrutura Molecular , Quercetina/análogos & derivados , Quercetina/análise
4.
Zhongguo Zhong Yao Za Zhi ; 45(4): 884-889, 2020 Feb.
Artigo em Chinês | MEDLINE | ID: mdl-32237489

RESUMO

To establish a content determination method for quality control of the pieces and standard decoction of honey-fried Descurainiae Semen. Standard decoction of honey-fried Descurainiae Semen was prepared with standardized process, and high performance liquid chromatography coupled with diode-array detector(HPLC-DAD) was used to detect its characteristic fingerprint and determine the content of quercetin-3-O-ß-D-glucose-7-O-ß-D-gentiobioside. In addition, the transfer rate, dry extract rate and pH value were calculated. The results showed that the established method had a high accuracy. The content of quercetin-3-O-ß-D-glucose-7-O-ß-D-gentiobioside in 13 batches of standard decoction was 0.03-0.12 mg·mL~(-1); the transfer rate was 13.4%-23.1%; the rate of extracts was 1.9%-5.5%, and the pH was between 5.4-5.9. The similarity coefficients were all greater than 0.85, indicating good homogeneity for the different batches of decoction. There were 7 common peaks in the characteristic chromatogram, one of which was quercetin-3-O-ß-D-glucose-7-O-ß-D-gentiobioside. In this paper, the established content determination and quality evaluation method for Descurainiae Semen pieces and decoction was simple, rapid and reproducible, providing reference for the quality control of honey-fried Descurainiae Semen pieces, standard decoction and its preparations.


Assuntos
Brassicaceae/química , Medicamentos de Ervas Chinesas/normas , Mel , Sementes/química , Cromatografia Líquida de Alta Pressão , Glucosídeos/análise , Controle de Qualidade , Quercetina/análogos & derivados
5.
Food Chem ; 321: 126644, 2020 Aug 15.
Artigo em Inglês | MEDLINE | ID: mdl-32247886

RESUMO

Genetics and environment both influence the content of hop (Humulus lupulus L.) aroma compounds. The effects of these two factors on aroma glycosides, which can change the aroma profile of beer over time, were examined in a preliminary study. Twenty-three hop cultivars were grown in the northwestern United States in two locations with distinct terroirs. UPLC-MS/MS analysis of hop cone extracts revealed that growing location had a large effect on hexyl glucoside levels but only a negligible effect on levels of linalyl, raspberry ketone, and 2-phenylethyl glucoside, which were mostly affected by genetic differences. The large terroir effect on hexyl glucoside, which releases a green leaf volatile with a grassy aroma when hydrolyzed, but not on the other aroma glucosides, which have more desirable aromas when hydrolyzed, could have an impact on beer aroma profiles.


Assuntos
Glucosídeos/análise , Glicosídeos/química , Humulus/química , Odorantes/análise , Cromatografia Líquida de Alta Pressão , Cor , Glucosídeos/química , Glicosilação , Estrutura Molecular , Folhas de Planta/química , Espectrometria de Massas em Tandem
6.
Food Chem ; 321: 126741, 2020 Aug 15.
Artigo em Inglês | MEDLINE | ID: mdl-32276146

RESUMO

Buckwheat sprouts (BS) becomes popular due to its' health-promoting properties as food product. The effects of fermentation with Saccharomyces cerevisiae and Lactobacillus plantarum on antioxidant and hypolipidemic activities as well as functional composition in common BS cultivated in maifanite mineral water were investigated here. DPPH and ·OH results showed higher antioxidant potential in fermented BS compared to unfermented BS, due to the higher rutin, orientin, isoorientin, vitexin, isovitexin, and total phenolic and flavonoid contents. The S. cerevisiae-fermented BS also exhibited 113% and 110% higher DPPH and ·OH scavenging activities than the L. plantarum-fermented BS, respectively. In hyperlipidemic mice, blood lipid parameters were improved as dose-dependent manner when supplemented the food with S. cerevisiae-fermented BS. Fermented BS also restored liver antioxidant levels significantly. The fermented BS had greater effect on different parameters than those of unfermented BS. Therefore, fermentation is a valuable method to enhance the bioactive potential of BS.


Assuntos
Antioxidantes/análise , Fagopyrum/química , Fagopyrum/crescimento & desenvolvimento , Alimentos e Bebidas Fermentados/análise , Águas Minerais , Animais , Antioxidantes/farmacologia , Apigenina/análise , Fagopyrum/metabolismo , Fermentação , Flavonoides/análise , Glucosídeos/análise , Hiperlipidemias/dietoterapia , Lactobacillus plantarum , Masculino , Camundongos , Fenóis/análise , Rutina/análise , Saccharomyces cerevisiae , Plântula/crescimento & desenvolvimento
7.
Zhongguo Zhong Yao Za Zhi ; 45(1): 119-123, 2020 Jan.
Artigo em Chinês | MEDLINE | ID: mdl-32237420

RESUMO

Astragali Radix is commonly used as bulk medicinal materials. Chinese Pharmacopoeia contains about 150 compound preparations of Astragali Radix, but the sample preparation method under the determination of Astragali Radix content in Chinese Pharmacopoeia is tedious and time-consuming, not convenient for the test of a large number of samples. Therefore, it is of great significance to simplify the sample preparation method and improve the practicability of the method for the quality control of Astragali Radix and its preparations. In this study, ultrasonic extraction method was used instead of heated reflux extraction, and solid phase extraction method was used to enrich and prepare the samples. A set of practical quality evaluation method was established for Astragali Radix slices and standard decoction, greatly shortening the sample preparation time and improving the accuracy of the method. The results of Astragali Radix standard decoction analysis showed that the transfer rate of calycosin 7-O-ß-D-glucospyranoside,(96.5±28.7)%, had great variation, which was found to be related to the conversion of mulberry isoflavone glucoside into calycosin 7-O-ß-D-glucospyranoside during the preparation of standard decoction. The transfer rates were(59.4±14.4)% and(101.3±12.3)% for calycosin and astragaloside Ⅳ respectively, which were relatively stable. Therefore, it is suggested that Astragali Radix slices and water decoction preparations should be evaluated by using calycosin and astragaloside Ⅳ as the quality evaluation index. The results provide a scientific and practical method for quality control of Astragali Radix slices and its standard decoction, and also provide scientific evidence for quality evaluation of the preparations.


Assuntos
Astrágalo (Planta)/química , Medicamentos de Ervas Chinesas/análise , Medicamentos de Ervas Chinesas/normas , Glucosídeos/análise , Raízes de Plantas/química , Controle de Qualidade , Extração em Fase Sólida
8.
PLoS One ; 15(2): e0228641, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-32053630

RESUMO

The use of plant tissue analysis as a tool for attaining low cyanogenic glucoside levels in cassava roots, has hardly been investigated. Just as the quality of crops is improved through the use of plant tissue analysis, the same can probably be done to consistently attain the lowest possible cyanogenic glucoside levels in cassava roots. High levels of cyanogenic glucosides in consumed fresh cassava roots or in their products have the potential of causing cyanide intoxication, hence the need to lower them. An experiment was thus conducted to assess the occurrence of meaningful relationships between plant nutritional status and cyanogenic glucoside production in cassava roots. Total hydrogen cyanide (HCN) levels in cassava roots were used to assess cyanogenic glucoside production. Using NPK fertiliser application to induce changes in plant nutritional status, the main objective of the study was investigated using the following sub-objectives; (1) to determine the effects of increased NPK fertiliser application on cassava root HCN levels; (2) and to show the occurrence of relationships between changes in nutrient levels in plant 'indicator tissue' and HCN levels in cassava roots. The study was a field experiment laid out as a split-plot in a randomized complete block design with three replicates. It was repeated in two consecutive years, with soil nutrient deficiencies only being corrected in the second year. The varieties Salanga, Kalinda, Supa and Kiroba were used in the experiment, while the NPK fertiliser treatments included; a control with no fertiliser applied; a moderate NPK treatment (50 kg N + 10 kg P + 50 kg K /ha); and a high NPK treatment (100 kg N + 25 kg P + 100 kg K /ha). A potassium only treatment (50 kg K/ha) was also included, but mainly for comparison. The root HCN levels of Salanga, Kalinda and Kiroba were significantly influenced by NPK fertiliser application in at least one of the two field experiments, while those of Supa remained uninfluenced. Changes in plant nutritional status in response to fertiliser application were thus shown to influence cyanogenic glucoside production. The results of the multiple linear regression analysis for the first field experiment, generally showed that the root HCN levels of some cassava varieties could have been 'reduced' by decreasing concentrations of nitrogen, potassium and magnesium in plants, or by improving plant calcium concentrations along with NPK fertiliser application. However, in the second field experiment (with corrected soil nutrient deficiencies) the regression analysis generally showed that the root HCN levels of some cassava varieties could have been 'reduced' by improving either one or a combination of the nutrients phosphorous, zinc and potassium in plants along with NPK fertiliser application. Although the results obtained in the two experiments had been contradicting due to slight differences in how they were conducted, the study had nonetheless demonstrated the occurrence of meaningful relationships between plant nutritional status and cyanogenic glucoside production; confirming the possible use of plant tissue analysis in predicting fertiliser needs for the consistent attainment of low cyanogenic glucosides in cassava roots.


Assuntos
Fertilizantes , Glucosídeos/análise , Cianeto de Hidrogênio/análise , Manihot/química , Nitrilos/análise , Raízes de Plantas/química , Agricultura , Produtos Agrícolas/química , Cianetos/análise , Glicosídeos/análise , Concentração de Íons de Hidrogênio , Modelos Lineares , Nitrogênio/análise , Fósforo/análise , Potássio/análise , Solo
9.
PLoS One ; 15(2): e0220084, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-32074105

RESUMO

Bletilla striata is an endangered traditional Chinese medicinal plant with multiple uses and a slow regeneration rate of its germplasm resources. To evaluate the callus growth kinetics and accumulation of secondary metabolites (SMs), a callus suspension culture was proven to be a valuable approach for acquiring high yields of medicinal compounds. An effective callus suspension culture for obtaining B. striata callus growth and its SMs was achieved with the in vitro induction of calluses from B. striata seeds. The callus growth kinetics and accumulation of SMs were analyzed using a mathematical model. The resulting callus growth kinetic model revealed that the growth curves of B. striata suspension-cultured calluses were sigmoidal, indicating changes in the growth of the suspension-cultured calluses. Improved Murashige and Skoog callus growth medium was the most favorable medium for B. striata callus formation, with the highest callus growth occurring during the stationary phase of the cultivation period. Callus growth acceleration started after 7 days and thereafter gradually decreased until day 24 of the cultivation period and reached its highest at day 36 period in both the dry weight and fresh weight analyses. The coelonin concentration peaked during the exponential growth stage and decreased afterward during the stationary stage of the callus suspension culture. The maximum content of coelonin (approximately 0.3323 mg/g callus dry weight) was observed on the 18th day of the cultivation cycle, while dactylorhin A and militarine reached the highest concentrations at day 24, and p-hydroxybenzyl alcohol at day 39. This investigation also laid a foundation for a multimathematical model to better describe the accumulation variation of SMs. The production of SMs showed great specificity during callus growth and development. This research provided a well-organized way to increase the accumulation and production of SMs during the scaled-up biosynthesis of calluses in B. striata callus suspension cultures.


Assuntos
Calo Ósseo/crescimento & desenvolvimento , Técnicas de Cultura de Células/métodos , Plantas Medicinais/metabolismo , Glucosídeos/análise , Cinética , Modelos Teóricos , Metabolismo Secundário , Sementes/química , Succinatos/análise
10.
Food Chem ; 317: 126398, 2020 Jul 01.
Artigo em Inglês | MEDLINE | ID: mdl-32086122

RESUMO

Malvidin-3-O-glucoside, malvidin-3,5-O-diglucoside, malvidin-3-O-(6-O-coumaroyl)-glucoside-5-O-glucoside from Chinese Vitis davidii red wine were used to investigate the role of glucoside, diglucoside and coumaroylated glucoside moieties on their transport efficiency through MKN-28 gastric and Caco-2 intestinal cells. Due to the already described conversion of 3-O-glucosylated anthocyanins into 3-O-glucuronidated, the 3-O-glucuronidated metabolite of malvidin-3-O-glucoside was also tested. The antiproliferative activity was higher for the glucuronidated metabolite in both cell lines. All anthocyanins were transported through MKN-28 gastric cells and Caco-2 intestinal cells with transport efficiencies ranging from 4% to 9% in MKN-28 and from 3% to 5% in Caco-2. No significant differences on transport efficiencies were observed at 180 min among the different anthocyanins in MKN-28. The transport efficiency of malvidin-3-O-glucuronide at 180 min was about 3-4% in Caco-2 and MKN-28 cells. Computational studies were performed to evaluate the interaction between anthocyanins and glucose gastric transporters GLUT1 and GLUT3, which supported the experimental findings.


Assuntos
Antocianinas/farmacocinética , Vitis/química , Vinho , Antocianinas/análise , Antocianinas/química , Células CACO-2 , Sobrevivência Celular/efeitos dos fármacos , Transportador de Glucose Tipo 1/química , Transportador de Glucose Tipo 1/metabolismo , Transportador de Glucose Tipo 3/química , Transportador de Glucose Tipo 3/metabolismo , Glucosídeos/análise , Glucosídeos/química , Glucosídeos/farmacocinética , Humanos , Inativação Metabólica , Absorção Intestinal , Simulação de Acoplamento Molecular
11.
J Chromatogr A ; 1620: 460978, 2020 Jun 07.
Artigo em Inglês | MEDLINE | ID: mdl-32106966

RESUMO

To explore the retention and separation of stevioside polar compounds on a sulfonic acid-functionalized cation exchange column, the effects of different organic solvent-water mobile phases on the retention behavior of polar rebaudioside A (RA) and its analogues on the column were investigated over a wide range of organic solvent contents. The obtained U-shape curves hinted that the retention of the compounds on the same column transitioned from a reversed-phase liquid chromatography (RPLC) mode to a hydrophilic interaction liquid chromatography (HILIC) mode when the water-rich state in the mobile phases changed to an organic solvent-rich state. Under the RPLC mode, no separation of RA from its analogues was observed. The HILIC mode was beneficial to the retention and separation of RA and its analogues. Compared with polar protic solvents, aprotic solvents were more conducive to the retention and separation of the polar compounds based on the HILIC mode in organic solvent-rich mobile phases. Three models were used to evaluate and discuss the HILIC retention and separation of the compounds on the column. In the aprotic solvent-rich mobile phase, the HILIC retention of RA and its analogues was effectively described by a mixed-mode model; in the polar proton solvent-rich mobile phase, the retention of analytes was best described by an linear solvation strength (LSS) model. The content and composition of the organic solvent in the mobile phase were determined to be important influencing factors that regulated the retention time for the RA and its analogues, and even the separation mechanism for HILIC. The present work provides a theoretical basis for guiding one to prepare high-purity RA from its analogues by predicting the retention time.


Assuntos
Diterpenos de Caurano/análise , Glucosídeos/análise , Ácidos Sulfônicos/química , Cromatografia de Fase Reversa , Diterpenos de Caurano/química , Glucosídeos/química , Interações Hidrofóbicas e Hidrofílicas , Troca Iônica , Compostos Orgânicos/química , Solventes/química , Água/química
12.
Phytomedicine ; 68: 153181, 2020 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-32065954

RESUMO

BACKGROUND: Eleutherococcus senticosus or Siberian ginseng is a medicinal plant containing adaptogenic substances believed to regulate immune responses. Both, the root and stem bark are commonly used in traditional medicines. PURPOSE: The purpose of the present study is to chemically characterize E. senticosus root and bark extracts and to compare their effects on functions of human primary macrophages. STUDY DESIGN AND METHODS: HPLC-DAD-MS analysis was used to characterize chemical constituents of alcoholic extracts from E. senticosus root and bark. The data obtained and available databases were combined for network pharmacology analysis. Involvement of predicted pathways was further functionally confirmed by using monocyte-derived human macrophages and endotoxin-free E. senticosus root and bark extracts. RESULTS: Chemical analysis showed that the root extract contained more syringin, caffeic acid, and isofraxidin than the bark extract. At variance, bark extract contained more sesamin and oleanolic acid. Coniferyl aldehyde and afzelin were below the limit of quantification in both extracts. Network pharmacology analysis indicated that constituents of E. senticosus might affect the immune cell phenotype and signaling pathways involved in cell metabolism and cytoskeleton regulation. Indeed, both extracts promoted actin polymerization, migration, and phagocytosis of E. coli by macrophages pointing to macrophage polarization towards the M2 phenotype. In addition, treatment with E. senticosus root and bark extracts decreased phosphorylation of Akt on Ser473 and significantly reduced expression of the hemoglobin scavenger receptor CD163 by macrophages. Neither extract affected expression of CD11b, CD80, or CD64 by macrophages. In addition, macrophages treated with the bark extract, but not with the root extract, exhibited activated p38 MAPK and NF-κB and released increased, but still moderate, amounts of proinflammatory TNF-α and IL-6, anti-inflammatory IL-10, and chemotactic CCL1, which all together point to a M2b-like macrophage polarization. Differently, the root extract increased the IL-4-induced expression of anti-inflammatory CD200R. These changes in monocytes are in agreement with an increased M2a macrophage polarization. CONCLUSION: The ability of E. senticosus root and bark extracts to promote polarization of human macrophages towards anti-inflammatory M2a and M2b phenotypes, respectively, might underlay the immunoregulatory activities and point to potential wound healing promoting effects of this medicinal plant.


Assuntos
Eleutherococcus/química , Macrófagos/efeitos dos fármacos , Casca de Planta/química , Extratos Vegetais/farmacologia , Raízes de Plantas/química , Anti-Inflamatórios/farmacologia , Polaridade Celular/efeitos dos fármacos , Cumarínicos/análise , Dioxóis/análise , Glucosídeos/análise , Humanos , Lignanas/análise , Macrófagos/metabolismo , NF-kappa B/metabolismo , Fenilpropionatos/análise , Extratos Vegetais/análise , Extratos Vegetais/química , Plantas Medicinais/química
13.
J Food Sci ; 85(2): 486-492, 2020 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-31968393

RESUMO

Growing health concerns have increased interest in reducing the consumption of added sugars, which can be achieved by substituting or replacing sugar with sweeteners to maintain sensory intensity and quality. The growing availability of sweeteners has increased the complexity of the perceptual landscape as sweeteners differ in the qualitative, intensity, and temporal properties. A sweetener that can match the perceptual properties of sucrose in different food matrices is likely to have broad applications. In complex foods, sweetness is influenced by the taste interactions with the existing tastants and possible matrix effects that influence release and perception of sweetness. The current study compared the taste properties of three food matrices (black tea, chocolate milk, and natural yogurt) sweetened by sucrose to those sweetened using eight different sweeteners (acesulfame-K, aspartame, erythritol, luo han guo (Mogroside), palatinose (iso-maltulose), stevia (Reb-A), sucralose, and sucrose-allulose mixture) using Rate-All-That-Apply. The sensory properties of each sweetener differed across matrices, with sucrose-allulose mixture, aspartame, erythritol, palatinose, and sucralose having the most similar taste to sucrose across all foods. By contrast, acesulfame-K, stevia, and luo han guo had taste profiles that most varied from sucrose, characterized by side tastes such as bitterness, chemical taste, and a low sweetness. Sweeteners differed most from sucrose when presented in natural yogurt compared to tea and chocolate milk. A food's taste properties can suppress sweetness intensity and promote undesirable side tastes. Taken together, these findings highlight the importance of testing sweeteners in complex foods and help identify sweeteners and sweetener combinations that can replicate the sweetness of sucrose and support sugar reduction. PRACTICAL APPLICATION: Food manufacturers and researchers can refer to the results of the sensory profiles to identify suitable sweeteners substitutes for sucrose in foods with similar taste profiles to those tested. The current article highlights important changes to sweetener sensory properties when presented in different complex foods, and provides an indication of the potential for calorie reduction by substituting sucrose with a range of low or no calorie sweeteners.


Assuntos
Camellia sinensis/química , Chocolate/análise , Leite/química , Edulcorantes/análise , Chá/química , Iogurte/análise , Animais , Aspartame/análise , Bovinos , Diterpenos de Caurano/análise , Glucosídeos/análise , Humanos , Stevia/química , Sacarose/análogos & derivados , Sacarose/análise , Paladar , Chá/metabolismo
14.
J Photochem Photobiol B ; 203: 111768, 2020 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-31931383

RESUMO

In vitro callus cultures of Verbena officinalis L. were maintained on solid Murashige and Skoog medium, enriched with 1 mg dm-3 BA and 1 mg dm-3 IBA under LED lights (red, blue, red/blue 70%/30%), in darkness and under control fluorescent lamps. The measurements of 2 phenylpropanoid glycosides (verbascoside and isoverbascoside) and 23 phenolic acids were performed in methanolic extracts from the biomass collected after 2-, 3- and 4-week growth cycles using the HPLC-DAD method. The presence of verbascoside, isoverbascoside and additionaly 7 phenolic acids (protocatechuic, chlorogenic, vanillic, caffeic, ferulic, o-coumaric and m-coumaric acids) was confirmed in all extracts. Blue and red/blue lights stimulated the accumulation of verbascoside (max. of 6716 and 6023 mg 100 g-1 DW after a 4-week growth cycle) and isoverbascoside (max. 333 and 379 mg 100 g-1 DW also after 4 weeks). The maximum amounts of verbascoside and isoverbascoside were respectively 1.8- and 7.0-fold higher than under the control conditions. Phenolic acids were accumulated in different amounts, and the maximum total amounts ranged from 36 to 65 mg 100 g-1 DW. LED lights also stimulated their accumulation in comparison with darkness and control. The main phenolic acids included: m-coumaric acid (max. 39 mg 100 g-1 DW), ferulic acid (max. 12 mg 100 g-1 DW), and protocatechuic acid (max. 13 mg 100 g-1 DW). Additionally, the quantities of photosynthetic pigments (chlorophyll a, b and carotenoids) were estimated in acetonic extracts using spectrophotometry. Red/blue light stimulated the biosynthesis of pigments (max. total content 287 µg g-1 FW after 4-week growth cycles). This is the first study describing the effect of LED lights on the production of phenylpropanoid glycosides and phenolic acids in V. officinalis callus cultures. Very high amounts of verbascoside and isoverbascoside are interesting from a practical point of view.


Assuntos
Glucosídeos/metabolismo , Hidroxibenzoatos/metabolismo , Luz , Fenóis/metabolismo , Verbena/metabolismo , Biomassa , Carotenoides/análise , Clorofila/análise , Clorofila A/análise , Cromatografia Líquida de Alta Pressão , Glucosídeos/análise , Hidroxibenzoatos/análise , Fenóis/análise , Fotossíntese/efeitos da radiação , Análise de Componente Principal , Análise de Regressão , Espectrofotometria
15.
Food Chem ; 314: 126183, 2020 Jun 01.
Artigo em Inglês | MEDLINE | ID: mdl-31972407

RESUMO

Phenolic compounds largely contribute to the nutraceutical properties of virgin olive oil (VOO), the organoleptic attributes and the shelf life due to their antioxidant capabilities. Due to the relevance of malaxation in the oil extraction process, we tested the effects of malaxation time on the concentrations of relevant phenolic compounds in VOO, and we evaluated the influence of performing malaxation under vacuum. An increase in malaxation time significantly decreased the concentrations of aglycone isomers of oleuropein and ligstroside but, conversely, increased the oleocanthal and oleacein contents. Additionally, malaxation under vacuum led to an increase in phenolic contents compared to standard conditions carried out at atmospheric pressure. Finally, we explored the possibility of predicting the VOO oxidative stability on the basis of the phenolic profile, and a model (R2 = 0.923; p < 0.0001) was obtained by combining the concentration of the VOO phenolic compounds and the main fatty acids.


Assuntos
Manipulação de Alimentos/métodos , Azeite de Oliva/química , Fenóis/análise , Fenóis/química , Aldeídos/análise , Aldeídos/química , Monoterpenos Ciclopentânicos/análise , Monoterpenos Ciclopentânicos/química , Ácidos Graxos/análise , Ácidos Graxos/química , Glucosídeos/análise , Glucosídeos/química , Iridoides/análise , Iridoides/química , Azeite de Oliva/análise , Oxirredução , Piranos/análise , Piranos/química , Temperatura , Fatores de Tempo
16.
Food Chem ; 311: 125881, 2020 May 01.
Artigo em Inglês | MEDLINE | ID: mdl-31767487

RESUMO

The quality of a wine largely depends on the balance between its sourness, bitterness and sweetness. Recently, epi-dihydrophaseic acid-3'-O-ß-glucopyranoside (epi-DPA-G) and astilbin, two molecules obtained from grapes, have been shown to contribute notably to the sweet taste of dry wines. To study the parameters likely to affect their concentration, a new method was developed and optimized by LC-FTMS. Three gradients and five C18 columns were tested. Good results in terms of linearity (r2 > 0.9980), repeatability (RSD ≤ 3%), recovery (≥89%) and LOQ (≤20 µg.L-1) were obtained. The method was used to screen epi-DPA-G and astilbin in red wines of several vintages over one century. Both compounds were detected in all wines at concentrations varying from 1.2 to 14.7 mg/L for epi-DPA-G and from 0.5 to 42.6 mg/L for astilbin. Therefore, this new method can be used to quantify epi-DPA-G and astilbin reliably in wine.


Assuntos
Cromatografia Líquida de Alta Pressão , Espectrometria de Massas , Edulcorantes/análise , Vinho/análise , Ácidos Graxos Insaturados/análise , Flavonóis/análise , Glucosídeos/análise , Limite de Detecção , Reprodutibilidade dos Testes , Paladar , Vitis/química , Vitis/metabolismo
17.
Nat Prod Res ; 34(5): 706-709, 2020 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-30445845

RESUMO

Phyllanthus phillyreifolius (Euphorbiaceae), poorly studied plant species, was fractionated using conventional and high pressure extraction techniques such as supercritical fluid and pressurized liquid extractions. Lipophilic substances were extracted with n-hexane and supercritical CO2 with or without co-solvent ethanol, meanwhile higher polarity fractions were recovered with acetone and 70% ethanol. Antioxidant potential was assessed by various chemical assays, which revealed that 70% ethanol was the most effective solvent for recovery of antioxidants. UPLC-MS phytochemical analysis of hydrophilic extracts confirmed geraniin as the main constituent of P. phillyreifolius. Other quantitatively important compounds were phyllanthusiin D and elaeocarpusin. Three isomers of tocopherol (α, ß and γ) were quantified by HPLC in lipofhilic extracts. Generally, the results from this study revealed high antioxidant potential of P. phillyreifolius; consequently the plant may be considered as a promising source of antioxidants for functional foods, nutraceuticals and pharmaceutical formulations.


Assuntos
Antioxidantes/isolamento & purificação , Phyllanthus/química , Compostos Fitoquímicos/farmacologia , Extratos Vegetais/química , Solventes/química , Antioxidantes/química , Cromatografia Líquida de Alta Pressão , Glucosídeos/análise , Taninos Hidrolisáveis/análise , Compostos Fitoquímicos/análise , Compostos Fitoquímicos/isolamento & purificação , Espectrometria de Massas em Tandem , Tocoferóis/isolamento & purificação , Tocoferóis/farmacologia
18.
Food Chem ; 307: 125527, 2020 Mar 01.
Artigo em Inglês | MEDLINE | ID: mdl-31648179

RESUMO

We report on a sensitive and fast quantitative MALDI-MS/MS method used to assess saffron authenticity by direct analysis through the determination of picrocrocin as the saffron authenticity marker, and using curcumin as the non-isotopic isobaric internal standard. The internal standard curcumin yielded good linearity (R2 = 0.994), and with confidence intervals at 95% for intercept. The detectable maximum adulteration percentage (99.0%) was estimated interpolating the limit of detection (LOD) for the isobaric internal standard in linear regression. The LOD was 47.63 ppm, and LOQ was 56.53 ppm. Good accuracy and precision were obtained for all concentrations. The capability of the MS approach to monitor analytes in a specific, selective fashion was used to obtain a semi-quantitative adulteration percentage and to establish the adulterant by additional experiments. The detection of gardecin and its derivatives in commercial samples indicated that Gardenia jasminoides Ellis was used as the adulterant.


Assuntos
Crocus/química , Cicloexenos/análise , Glucosídeos/análise , Espectrometria de Massas por Ionização e Dessorção a Laser Assistida por Matriz/métodos , Terpenos/análise , Calibragem , Curcumina/química , Cicloexenos/normas , Glucosídeos/normas , Limite de Detecção , Modelos Lineares , Espectrometria de Massas por Ionização e Dessorção a Laser Assistida por Matriz/normas , Terpenos/normas
19.
Artigo em Inglês | MEDLINE | ID: mdl-31881511

RESUMO

Systemic dry syndrome affects quality of life, and various effective methods are being developed for its treatment. We recently found that rooibos (Aspalathus linearis) extract activates muscarinic M3 receptor and improves dryness in mice and humans. We identified eriodictyol-6-C-ß-D-glucoside (E6CG) as the active component affecting the secretory functions of exocrine glands; however, the pharmacokinetics and distribution of E6CG in exocrine glands have not been elucidated in mice receiving rooibos extract. We have developed a quantification method using LC-MS/MS to detect E6CG without an internal standard. Experiments on C57BL/6 mice administered rooibos extract showed that E6CG was transferred into blood plasma, with its concentration levels peaking 19.3 min after treatment. Substantial levels of E6CG were detected in the submandibular, sublingual, parotid, and lacrimal glands and in the sweat glands in palm skin. This study reports that rooibos extracts containing E6CG can be used as functional foods for improving systemic dryness.


Assuntos
Aspalathus/química , Flavanonas/análise , Flavanonas/farmacocinética , Glucosídeos/análise , Glucosídeos/farmacocinética , Administração Oral , Animais , Flavanonas/química , Glucosídeos/química , Limite de Detecção , Modelos Lineares , Masculino , Camundongos , Camundongos Endogâmicos C57BL , Extratos Vegetais/administração & dosagem , Extratos Vegetais/química , Reprodutibilidade dos Testes , Glândulas Salivares/química , Pele/química , Distribuição Tecidual
20.
Oxid Med Cell Longev ; 2019: 5465463, 2019.
Artigo em Inglês | MEDLINE | ID: mdl-31827680

RESUMO

An optimisation of extraction towards an increased antioxidant capacity and the study on the extracts' composition by HPLC-ESI-Q-TOF-MS were performed on different organs of a rarely studied plant: Rheum cordatum Losinsk (Polygonaceae) growing in Kazakhstan. More than 20 compounds from anthraquinones and phenolics were identified in an optimised method. The plant was proven to contain a wide variety of phenolic compounds (catechins, flavonoids, and their glucosides and phenolic acids) in contrast to the anthraquinone composition, which was mainly represented by emodin and its analogues. The results of the studies could determine the plant as a rich source of pharmacologically precious polyphenols. It was evidenced that the extracting solvents, the time of collection, and the organs tested affected both the chemical content and the antioxidant potential of the extracts. Ethanol : water (50 : 50 v/v) was selected as the most beneficial extractant for all metabolites, and based on the principal component analysis of raw data, the radical scavenging potential of the plant was strictly related to the presence of epicatechin gallate (ECG), kaempferol glucoside, and epigallocatechin gallate (EGCG) occurring in this extract at the concentration of 1.69-5%, 0.16-0.47%, and 0.001-2.93%, respectively.


Assuntos
Antioxidantes/química , Compostos Fitoquímicos/análise , Rheum/química , Antraquinonas/análise , Antraquinonas/química , Catequina/análogos & derivados , Catequina/análise , Cromatografia Líquida de Alta Pressão , Glucosídeos/análise , Quempferóis/análise , Cazaquistão , Fenóis/análise , Fenóis/química , Compostos Fitoquímicos/química , Análise de Componente Principal , Rheum/metabolismo , Espectrometria de Massas por Ionização por Electrospray
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