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1.
J Food Sci Technol ; 59(8): 3210-3219, 2022 Aug.
Artículo en Inglés | MEDLINE | ID: mdl-35872710

RESUMEN

Response surface methodology was used to optimize the chestnut beverage production under the effect of the independent variables including dilution rate (x 1 ), dilution temperature (x 2 ), pasteurization time (x 3 ) and pasteurization temperature (x 4 ). The experiments were based on a central composite design with linear and quadratic models employed to study the combined effects of four independent variables. The responses were selected with functional properties such as antioxidative attributes and total phenolic content. The optimal conditions (x 1 , x 2 , x 3 and x 4 ) determined for development of chestnut based functional beverage were a dilution rate of 25.19 g/100 mL, a dilution temperature of 37.562 °C, a pasteurization time of 24.996 min. and a pasteurization temperature of 84.433 °C. After comparing the predicted and experimental results, the multi-response surface methodology was more stable with a good correlation for a functional chestnut beverage.

2.
J Biol Inorg Chem ; 25(1): 161-177, 2020 02.
Artículo en Inglés | MEDLINE | ID: mdl-31832781

RESUMEN

In this work, mixed ligand complexes of Co(II) Ni(II) and Cu(II) were synthesized using quercetin and diimine (1,10-phenanthroline or 2,2'-bipyiridine) ligands. The obtained Ni(II) and Co(II) complexes are new and the Cu(II) complexes are synthesized by different method from the literature. The characterization of complexes was performed by elemental analysis, thermogravimetric analysis, ESI-MS, UV-visible and infrared spectral analyses, magnetic susceptibility and molar conductivity measurements. It was found that quercetin, diimine and metal(II) ion form 1:1:1 complexes. Resulting data supported octahedral geometry for Ni(II) and Co(II) complexes and square pyramidal geometry for Cu(II) complexes. The proposed compositions are [Co(queH-1)Cl(phen)(H2O)]∙2H2O (1, queH = quercetin, phen = 1,10-phenanthroline), [Ni(queH-1)Cl(phen)(H2O)]∙2H2O (2), [Cu(queH-1)Cl(phen)]∙2.5H2O (3) and [Cu(queH-1)Cl(bpy)]∙2H2O (4, bpy = 2,2'-bipyiridine). Antioxidant capacity and total phenolic content of complexes measured by Folin-Ciocalteu and ABTS methods. Anti-cancer effect of these compounds were tested against different cancer cells (A549, PC-3, HeLa and MCF-7). Apoptosis identified by the fluorescence imaging, caspase cleaved cytokeratin-18 and flow cytometry analysis (annexin V, caspase 3/7, mitochondria membrane potential and oxidative stress). As a result, Cu(II) complexes are more effective than the other compounds and Complex 3 is a promising anti-cancer compound against breast cancer MCF-7 and MDA-MB-231 cells (IC50 values are 2.4 and 5.4 µM for 48 h, respectively). Flow cytometry analysis exhibited that Complex 3 caused apoptosis in MCF-7 cells. These results support that Complex 3 has anticancer activity and can be a potential anticancer agent especially in breast cancer.


Asunto(s)
Antineoplásicos/farmacología , Antioxidantes/farmacología , Cobalto/química , Complejos de Coordinación/química , Complejos de Coordinación/farmacología , Cobre/química , Iminas/química , Níquel/química , Quercetina/química , Línea Celular Tumoral , Humanos , Ligandos , Análisis Espectral/métodos
3.
J Dairy Sci ; 101(5): 3788-3798, 2018 May.
Artículo en Inglés | MEDLINE | ID: mdl-29477522

RESUMEN

This research aimed to evaluate the effects of using either grain or commercial starter culture on the antioxidative capacity of cow and ewe milk kefirs. The antioxidant capacity of kefir samples during fermentation and 21 d of storage was assessed by using 3 assays: 2,2'-azino-bis(3-ethylbenzthiazoline-6-sulfonic acid) (ABTS) radical cation decolorization; 2,2-diphenyl-1-picrylhydrazyl (DPPH•) radical scavenging activity assay; and Fe+3-reducing power (ferric reducing antioxidant power assay, FRAP). Vitamin E and ß-carotene contents were also quantified. All kefir samples exhibited varying values for DPPH, ABTS, and FRAP assays depending on the starter culture and milk type. Vitamin E and ß-carotene contents were similar in all kefir samples during storage. The results of this study suggest that milk type (cow or ewe) and culture type (kefir grains or commercial starter) were the significant parameters for the antioxidative activity of kefir.


Asunto(s)
Antioxidantes/análisis , Kéfir/análisis , Leche/química , Animales , Compuestos de Bifenilo/análisis , Bovinos , Femenino , Fermentación , Ovinos , Vitamina E/análisis
4.
Cell Mol Neurobiol ; 35(2): 175-87, 2015 Mar.
Artículo en Inglés | MEDLINE | ID: mdl-25212824

RESUMEN

Glioblastoma multiforme (GBM) is one of the deadliest human malignancies. A cure for GBM remains elusive, and the overall survival time is less than 1 year. Thus, the development of more efficient therapeutic approaches for the treatment of these patients is required. Induction of tumor cell death by certain phytochemicals derived from medicinal herbs and dietary plants has become a new frontier for cancer therapy research. Although the cancer suppressive effect of Ficus carica (fig) latex (FCL) has been determined in a few cancer types, the effect of this latex on GBM tumors has not been investigated. Therefore, in the current study, the anti-proliferative activity of FCL and the effect of the FCL-temozolomide (TMZ) combination were tested in the T98G, U-138 MG, and U-87 MG GBM cell lines using the WST-1 assay. The mechanism of cell death was analyzed using Annexin-V/FITC and TUNEL assays, and the effect of FCL on invasion was tested using the chick chorioallantoic membrane assay. To determine the effect of FCL on GBM progression, the expression levels of 40 GBM associated miRNAs were analyzed in T98G cells using RT-qPCR. According to the obtained data, FCL causes cell death in GBM cells with different responses to TMZ, and this effect is synergistically increased in combination with TMZ. In addition, the current study is the first to demonstrate the effect of FCL on modulation of let-7d expression, which may be an important underlying mechanism of the anti-invasive effect of this extract.


Asunto(s)
Neoplasias Encefálicas/genética , Neoplasias Encefálicas/patología , Ficus/química , Glioblastoma/genética , Glioblastoma/patología , Látex/uso terapéutico , MicroARNs/genética , Antineoplásicos/farmacología , Antineoplásicos/uso terapéutico , Apoptosis/efectos de los fármacos , Línea Celular Tumoral , Proliferación Celular/efectos de los fármacos , Supervivencia Celular/efectos de los fármacos , Fraccionamiento Químico , Dacarbazina/análogos & derivados , Dacarbazina/farmacología , Dacarbazina/uso terapéutico , Regulación Neoplásica de la Expresión Génica/efectos de los fármacos , Humanos , Etiquetado Corte-Fin in Situ , Látex/farmacología , MicroARNs/metabolismo , Modelos Biológicos , Invasividad Neoplásica , Neovascularización Fisiológica/efectos de los fármacos , Fitoterapia , Extractos Vegetales/farmacología , Extractos Vegetales/uso terapéutico , Temozolomida
5.
J Food Sci ; 89(6): 3649-3665, 2024 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-38706382

RESUMEN

Society's interest in natural and clean products in many areas, such as food and cosmetics, has increased considerably. It has led to the development of new techniques in the packaging of products so that the wastes from the preferred products can be recycled. In this context, Pinus brutia bark was preferred within the scope of the study to transform natural wastes into functional components and use them as packaging material. P. brutia bark (PBB) samples were collected from Bursa, Turkey. PBB samples were ultrasonically extracted using various solvents (acetone, butanol, ethanol, ethyl acetate, hexane, methanol, petroleum ether, and water) and a solvent-acidic hydrolysis system. The phenolic content profile of PBB samples was determined using high-performance liquid chromatography with diode-array detection, and total flavonoid content, antioxidant capacity, and total phenolic content were determined. Chitosan-polyvinyl alcohol (CS-PVA) films loaded with polysaccharides and containing methanolic extract were developed. The physical, chemical, and mechanical properties of the films were characterized. It is known that the thickness of the films determines the mechanical properties required to maintain the integrity of the packaging during storage and transport. From the results of the study, it was concluded that the elongation at break value was higher in CS-PVA-PBB-M films (111.08% ± 10.46%), Young's modulus (31.74 ± 21.37 N/mm2), and tensile strength (3.01 ± 0.50 N/mm2) values were higher in CS-PVA films. In this case, it was concluded that adding proanthocyanidin to edible films gives flexibility to the films.


Asunto(s)
Antioxidantes , Embalaje de Alimentos , Fenoles , Pinus , Corteza de la Planta , Extractos Vegetales , Polisacáridos , Corteza de la Planta/química , Extractos Vegetales/química , Pinus/química , Antioxidantes/química , Polisacáridos/química , Embalaje de Alimentos/métodos , Fenoles/análisis , Fenoles/química , Resistencia a la Tracción , Quitosano/química , Flavonoides/análisis , Flavonoides/química , Alcohol Polivinílico/química , Cromatografía Líquida de Alta Presión
6.
J Food Sci ; 88(6): 2571-2582, 2023 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-37212525

RESUMEN

In this study, the bark of the Aquilaria agallocha was extracted, and the phenolic content of A. agallocha extract was determined using high-performance liquid chromatography-diode array detector. The A. agallocha extract-chitosan edible films were prepared by using a different amount of A. agallocha extract (0, 1, 4, and 8 mL) and chitosan solution. Some physical properties of A. agallocha extract-chitosan edible films, water vapor permeability, solubility, swelling ratio, humidity ratio, thickness, scanning electron microscopy, and Fourier transform infrared spectroscopy analysis were investigated. The antibacterial activities, total phenolic content, and antioxidant capacity analysis of the A. agallocha extract-chitosan edible films were performed. The total phenolic content (0, 1, 4, and 8 mL of A. agallocha extract-chitosan edible films 0.92 ± 0.09, 1.34 ± 0.04, 2.94 ± 0.10, and 4.62 ± 0.10 mg gallic acid equivalent (GAE)/g film, respectively) and antioxidant capacity (0, 1, 4, and 8 mL of A. agallocha extract-chitosan edible films 52.61 ± 2.85, 104.28 ± 4.78, 304.30 ± 18.23, and 592.11 ± 0.67 mg Trolox equivalent (TE)/g film, respectively) of A. agallocha extract-chitosan edible films increased with the increase in the amount of extract. At the same time, the increase in the amount of antioxidant capacity improved the physical features of the films. The results of the antibacterial activity studies showed that all of the A. agallocha extract-chitosan edible films prevented bacterial growth from Escherichia coli and Staphylococcus aureus considering controlling group. PRACTICAL APPLICATIONS: To investigate the activity of antioxidant extract-biodegradable film, the A. agallocha extract-chitosan edible film had prepared. The results showed that A. agallocha extract-chitosan edible film was antioxidant and antibacterial properties and was used as food packaging material successfully.


Asunto(s)
Antioxidantes , Quitosano , Antioxidantes/farmacología , Antioxidantes/química , Quitosano/química , Antibacterianos/farmacología , Antibacterianos/química , Permeabilidad , Embalaje de Alimentos/métodos , Fenoles
7.
J Food Sci ; 85(4): 998-1006, 2020 Apr.
Artículo en Inglés | MEDLINE | ID: mdl-32154918

RESUMEN

Ellagic acid (EA), a naturally occurring bioactive phenolic compound largely found in pomegranate, exhibits significant health benefits due to its antioxidant, antimutagenic, and even anticancerogenic properties. The present work aimed to microencapsulate EA extracted from pomegranate peels. To improve the stability of EA, microencapsulation was applied with Spirulina as a coating material. For this purpose, ethanolic extracts obtained from pomegranate peels were used for microencapsulation. Response surface methodology combined with a three-level, three-variable Box-Behnken design (BBD) was applied to obtain optimum microencapsulation. The microparticles obtained under the optimized encapsulation conditions were further characterized by FT-IR and SEM. The results confirmed the encapsulation of EA in Spirulina cells. Then, the optimum microparticles were used in an in vitro release study. The results of the in vitro digestion with simulated gastrointestinal fluids could help to determine the content and biological activity of EA. In this study, the effect of encapsulation on the release properties of EA during simulated gastrointestinal digestion was also evaluated. HPLC-DAD analysis and the Folin-Ciocalteu and ABTS methods were helpful for characterization of EA in the simulated fluids. The release profile of EA indicated that in simulated intestinal fluid, the release was faster than that in gastric fluid. PRACTICAL APPLICATION: This study describes the microencapsulation of ethanolic extracts of pomegranate peel (PP) in Spirulina. This application has been performed to improve the stability and bioavailability of EA in the extracts. Optimum microencapsulation was obtained by response surface methodology with BBD. After the characterization of the obtained optimum Spirulina/EA mixture by FT-IR and SEM, an in vitro release study was conducted for stability research. The results will guide other researchers working on the determination of the content and biological activity of EA and on optimizing the microencapsulation process.


Asunto(s)
Ácido Elágico/química , Ácido Elágico/metabolismo , Microalgas/química , Extractos Vegetales/química , Extractos Vegetales/metabolismo , Granada (Fruta)/química , Antioxidantes/química , Antioxidantes/metabolismo , Digestión , Composición de Medicamentos , Frutas/química , Tracto Gastrointestinal/metabolismo , Humanos , Cinética , Modelos Biológicos , Fenoles/química , Fenoles/metabolismo , Granada (Fruta)/metabolismo , Espectroscopía Infrarroja por Transformada de Fourier , Residuos/análisis
8.
J Food Biochem ; 43(7): e12888, 2019 07.
Artículo en Inglés | MEDLINE | ID: mdl-31353705

RESUMEN

Chestnut bee pollen has potential nutritional and medicinal effects and is an important natural bee product. This study focused on the investigation of the antioxidant capacity and DNA damage inhibition ability of chestnut bee pollen (CBP) from Bursa (Turkey). The phenolic compounds (rosmarinic acid, vitexin, hyperoside, pinocembrin, trans-chalcone, apigenin, protocatechuic, and galangin) and carotenoids in CBPE were determined by HPLC-DAD (high-performance liquid chromatography-diode array detection). Additionally, the protective ability of CBPE against DNA damage by oxidation was investigated. In this study, it was determined that CBPE has a high total phenolic compound content, and the antioxidant capacity of CBPE inhibits DNA oxidation (34% reduction of DNA damage in Fenton reaction media). This study could reveal new information regarding the use of CBPE as a protective agent for DNA in the future. PRACTICAL APPLICATIONS: Phenolic compounds and carotenoids prevent some diseases because of their important biological activities. One of the potential food sources chestnut bee pollen contains sugar, carbohydrates, amino acids, proteins, lipids, vitamins, hormones, enzymes, and flavonoids. Chestnut bee pollen, which has protective activity against DNA oxidation, could be an excellent potential source of a protective agent against some degenerative diseases through future applications.


Asunto(s)
Antioxidantes/farmacología , Abejas/fisiología , Carotenoides/análisis , Fagaceae/química , Fenoles/farmacología , Extractos Vegetales/farmacología , Animales , Antioxidantes/química , Cromatografía Líquida de Alta Presión , Daño del ADN/efectos de los fármacos , Oxidación-Reducción/efectos de los fármacos , Fenoles/química , Extractos Vegetales/química , Polen/química
9.
Talanta ; 161: 503-510, 2016 Dec 01.
Artículo en Inglés | MEDLINE | ID: mdl-27769439

RESUMEN

Four different data representations were evaluated for the determination of the total antioxidant activities of four different Prunella L. species, which are Prunella vulgaris, Prunella grandiflora, Prunella laciniata, and Prunella orientalis Bornm. Three different antioxidant assays, 2,2'-azino-bis(3-ethylbenzothiazoline-6-sulfonic acid) (ABST), 2,2-diphenyl-1-picrylhydrazyl (DPPH), and Folin-Ciocalteu (FC) reagent measured the total antioxidant activity and phenolic content of the four Prunella L. species that were extracted with 12 different solvent systems. The data set of 48 Prunella L. extracts was collected by high-performance liquid chromatography (HPLC) with ultraviolet diode array detection. The prediction of total antioxidant activity of Prunella L. species by super partial least square (sPLS) regression was obtained using four different representations of the data; the entire two-way chromatographic-spectral images, the average UV spectra, the total absorbance chromatogram, the lambda max (λmax) chromatogram. The coefficients of determination (R2) for the entire two-way chromatographic-spectral images (the ABST (0.943±0.008), the DPPH (0.91±0.01), and the FC (0.963±0.006)) indicated good accuracy for predicting antioxidant activities. The three different wet chemical assays are known to yield different values so it is advantageous to estimate the three separate values with a single LC measurement. The entire two-way chromatographic-spectral images have been used to the first time for calibration. Acidic hexane, as an extraction solvent, gave the least root mean square error of prediction (RMSEP) for the two-way chromatographic-spectral images, so it would be the best solvent for modeling antioxidant activities.


Asunto(s)
Antioxidantes/química , Extractos Vegetales/química , Prunella , Benzotiazoles/química , Compuestos de Bifenilo/química , Cromatografía Líquida de Alta Presión/métodos , Indicadores y Reactivos/química , Análisis de los Mínimos Cuadrados , Molibdeno/química , Picratos/química , Solventes/química , Espectrofotometría Ultravioleta , Ácidos Sulfónicos/química , Compuestos de Tungsteno/química
10.
Iran J Pharm Res ; 15(2): 527-35, 2016.
Artículo en Inglés | MEDLINE | ID: mdl-27642324

RESUMEN

In this study, antioxidant and antimicrobial potentials of Usnea intermedia, U. filipendula, and U. fulvoreagens and their stictic and usnic acid contents were investigated. Antioxidant activity and total phenolic contents were evaluated in acetone, ethanol, and methanol extracts of these three species. Antioxidant activity was measured by ABTS [2,2'-azino-bis(3-ethylbenzothiazoline-6-sulphonic acid)] method and total phenolic contents were measured by Folin-Ciocalteu method. High-performance liquid chromatography (HPLC) was used for the determination of lichen acids. It can be concluded from stictic and usnic acids contents that the order of solvent efficiency is acetone > ethanol > methanol and acetone > methanol > ethanol, respectively. Broth microdilution method was performed to determine the minimum inhibitory concentration (MIC) of the methanol extracts of three Usnea species. The MIC values of all the extracts ranged from 64 µg/mL to 512 µg/mL for all the bacterial strains that were tested in this study, and all the Fluoro quinolone-resistant Escherichia coli isolates (except for E101) were sensitive to the methanol extracts of the three Usnea species. This paper is the first study to determine the stictic acid content in U. intermedia and U. filipendula. Our findings indicate that these three Usnea species could be used as antioxidant and antimicrobial agents.

11.
Am J Cancer Res ; 4(5): 572-90, 2014.
Artículo en Inglés | MEDLINE | ID: mdl-25232498

RESUMEN

The stem-like cells of Glioblastoma multiforme (GBM) tumors (GSCs) are one of the important determinants of recurrence and drug resistance. The aims of the current study were to evaluate the anticancer effect of Olea europaea leaf extract (OLE) on GBM cell lines, the association between OLE and TMZ responses, and the effect of OLE and the OLE-TMZ combination in GSCs and to clarify the molecular mechanism of this effect on the expression of miRNAs related to cell death. The anti-proliferative activity of OLE and the effect of the OLE-TMZ combination were tested in the T98G, U-138MG and U-87MG GBM cell lines using WST-1 assay. The mechanism of cell death was analyzed with Annexin V/FITC and TUNEL assays. The effects of OLE on the expression levels of miR-181b, miR-153, miR-145 and miR-137 and potential mRNA targets were analyzed in GSCs using RT-qPCR. OLE exhibited anti-proliferative effects via apoptosis and necrosis in the GBM cell lines. In addition, OLE significantly induced the expression of miR-153, miR-145, and miR-137 and decreased the expression of the target genes of these miRNAs in GSCs (p < 0.05). OLE causes cell death in GBM cells with different TMZ responses, and this effect is synergistically increased when the cells are treated with a combination of OLE and TMZ. This is the first study to indicate that OLE may interfere with the pluripotency of GSCs by modulating miRNA expression. Further studies are required, but we suggest that OLE may have a potential for advanced therapeutic cancer drug studies in GBM.

12.
Antioxidants (Basel) ; 2(4): 206-15, 2013 Sep 30.
Artículo en Inglés | MEDLINE | ID: mdl-26784459

RESUMEN

The popularity of fruit tea is increasing in the world because of its antioxidant properties and attractive taste. The aim of this study was to determine and compare the antioxidant property and phenolic composition of 16 different fruit teas. The antioxidant property and total phenol content of fruit teas depending on the extraction condition (water temperature) were examined using the ABTS (2,2-azinobis[3-ethylbenzothiazoline-6-sulphonic acid]) method and the Folin-Ciocalteu method, respectively. The contents of total flavonoid and total anthocyanin of fruit teas was determined by using the UV/Vis spectrophotometric method. The phenolic composition was determined and quantified by using high performance liquid chromatography and photodiode array detection (HPLC-PDA). The highest total phenol content and antioxidant capacity were determined in pomegranate (I). The highest contents of total flavonoid and total anthocyanin were determined in peach (III) and blackberry (I), respectively. Chlorogenic acid, quercetin, myricetin, rutin, rosmarinic acid and ferulic acid were determined in fruit teas. A water temperature of 100 °C was the most effective to extract the highest contents of total phenols, total flavonoids, total anthocyanins and the highest antioxidant capacity in 16 different fruit teas. The purpose of this study was to determine the effect of water temperature on the extraction and quantify the various phenolic compounds in fruit teas by HPLC method for industrial application in producing the extracts.

13.
Talanta ; 111: 119-24, 2013 Jul 15.
Artículo en Inglés | MEDLINE | ID: mdl-23622534

RESUMEN

A chromium reducing antioxidant capacity (CHROMAC) assay was presented to measure antioxidant capacity of selected plants and fruits and compared its performance with other commonly used antioxidant capacity methods of 2,2'-azinobis(3-ethylbenzothiazoline-6-sulfonic acid) (ABTS) and cupric reducing antioxidant capacity (CUPRAC). The assay is based on the spectrophotometric measurement of colored a chelate complex of Cr(III) and diphenylcarbazone formed by the reaction of Cr(VI) and 1,5-diphenylcarbazid in acidic medium. Phenolic compounds react with excessive amounts of Cr(VI) at low pH values, causing reduction of Cr(VI) to Cr(III) and conversion of phenols to oxidized products. The assay comprises of the antioxidant with a chromium(VI) solution, a 1,5-diphenylcarbazid in acidic medium and subsequent measurement of the developed absorbance at 540 nm after 50 min. The color development is stable for phenolic compounds in plant and fruit. The selectivity of the assay for phenolic compounds was improved by adjusting pH to 2.8 and reduction potential between 0.2 and 0.9 V. The developed assay was successfully applied to the measurement of antioxidant capacity of three plants and one fruit (Prunus divaricata Ledeb.subsp. divaricata) samples and comparable results were obtained by ABTS and CUPRAC assays.


Asunto(s)
Antioxidantes/análisis , Cromo/metabolismo , Frutas/metabolismo , Plantas/metabolismo , Antioxidantes/química , Cromo/química , Difenilcarbazida/química , Difenilcarbazida/metabolismo , Frutas/química , Concentración de Iones de Hidrógeno , Estructura Molecular , Oxidación-Reducción , Fenoles/química , Fenoles/metabolismo , Plantas/química , Prunus/química , Prunus/metabolismo , Reproducibilidad de los Resultados , Semicarbazonas/química , Semicarbazonas/metabolismo , Espectrofotometría
14.
Food Chem ; 141(2): 1361-8, 2013 Nov 15.
Artículo en Inglés | MEDLINE | ID: mdl-23790925

RESUMEN

Response surface methodology was used to optimise experimental conditions for ultrasonic-assisted extraction of phenolic compounds from Artemisia absinthium. The central composite design was employed, the extracts were characterised by the determination of total phenolic content and antioxidant capacity. The total phenolic contents of extracts were determined by Folin method and also total antioxidant capacities of extracts were determined by ABTS and CUPRAC methods. The phenolic compounds of A. absinthium at optimum extraction conditions were determined by HPLC-DAD. The optimum conditions were determined as HCl concentration between 0.41 and 0.44mol/L, methanol volume between 55% and 59% (v/v), extraction temperature between 64 and 70°C, extraction time between 101 and 107min. The experimental values agreed with those predicted within a 95% confidence level, thus indicating the suitability of response surface methodology in optimising the ultrasound-assisted extraction of phenolic compounds from A. absinthium.


Asunto(s)
Antioxidantes/aislamiento & purificación , Artemisia absinthium/química , Frutas/química , Fenoles/aislamiento & purificación , Extractos Vegetales/aislamiento & purificación , Ultrasonido/métodos , Antioxidantes/análisis , Cromatografía Líquida de Alta Presión , Fenoles/análisis , Extractos Vegetales/análisis
15.
J Pharm Biomed Anal ; 55(5): 1227-30, 2011 Jul 15.
Artículo en Inglés | MEDLINE | ID: mdl-21498022

RESUMEN

Four species of Prunella L. (Prunella vulgaris L., Prunella laciniata L., Prunella grandiflora L. and Prunella orientalis Bornm.) belong to the family of Lamiaceae and representing popular Western and Chinese herbal medicine were examined for the content of phenolic compounds. Phenolic acids (rosmarinic acid, caffeic acid, ferulic acid, chlorogenic acid, protocatechuic acid), flavonoids (rutin, quercetin) in different quantitative proportions depending on extracts were determined by the rapid, selective and accurate method combining solvent/acid hydrolysis extraction and high performance liquid chromatography-diode array detection (HPLC-DAD). Water, methanol, butanol, acetonitrile, ethyl acetate, hexane and their acidic solutions were used to examine the efficiency of different solvent systems for the extraction of phenolic compounds. Acid hydrolysis extraction was established as the most suitable extraction method for phenolic compounds.


Asunto(s)
Química Farmacéutica/métodos , Cromatografía Liquida/métodos , Fenol/química , Prunella/metabolismo , Técnicas de Química Analítica , Cromatografía Líquida de Alta Presión/métodos , Hidrólisis , Extractos Vegetales/química , Extractos Vegetales/farmacología , Solventes/química , Agua/química
16.
J Food Sci ; 75(4): C328-35, 2010 May.
Artículo en Inglés | MEDLINE | ID: mdl-20546390

RESUMEN

Raspberry (Aksu Kirmizisi, Rubin, Newburgh, Hollanda Boduru, Heritage) and blackberry (Bursa 1, Bursa 2, Jumbo, Chester) cultivars were assayed for antioxidant activity (determined as 2,2-azino-di-[3-ethylbenzothialozine-sulphonic acid][ABTS], 2,2-diphenyl-1-picrylhydrazyl radical [DPPH], and cupric ion reducing antioxidant capacity [CUPRAC]), total phenol, total flavonoid, and total anthocyanin contents. In addition, 10 anthocyanins and anthocyanidins were determined in raspberry and blackberry by liquid chromatography-mass spectrometry (LC-MS/MS). Raspberry and blackberry had the highest ABTS, DPPH, CUPRAC, total phenol, and total flavonoid contents in methanol extracts, whereas total anthocyanin contents were the highest in water extracts. The antioxidant activity of the raspberry and blackberry was directly related to the total amount of phenolic compounds detected in the raspberry and blackberry. All antioxidant activity values were highly correlated with anthocyanin content in blackberry (0.93 < or = r < or = 0.99, P = 0.05). On the other hand, high correlation between total flavonoid content and antioxidant activity was recorded in water extract of blackberry (0.91 < or = r < or = 0.93, P = 0.05). ABTS value was highly correlated with total flavonoid content in methanol extract (r = 0.90), whereas total flavonoid content was relatively less correlated with DPPH (r = 0.85) and CUPRAC (r = 0.89).


Asunto(s)
Antioxidantes/análisis , Frutas/química , Fenoles/análisis , Rosaceae/química , Algoritmos , Antocianinas/análisis , Antocianinas/química , Benzotiazoles/química , Compuestos de Bifenilo/química , Cromatografía Líquida de Alta Presión , Cobre/química , Flavonoides/análisis , Peso Molecular , Picratos/química , Extractos Vegetales/química , Especificidad de la Especie , Espectrometría de Masa por Ionización de Electrospray , Espectrofotometría , Ácidos Sulfónicos/química , Espectrometría de Masas en Tándem
17.
Anal Methods ; 1(3): 208-214, 2009 Dec 01.
Artículo en Inglés | MEDLINE | ID: mdl-32938060

RESUMEN

The multivariate calibration methods-moving window selection partial least squares regression (MWPLSR) and net analyte signal (NAS)-were employed for simultaneous determination of a mixture of C.I. Disperse Blue 183, C.I. Disperse Blue 79, C.I. Disperse Red 82, C.I. Disperse Red 65, C.I. Disperse Yellow 211 and C.I. Disperse Orange 25 by UV-vis spectrophotometry. The absorption spectra of the six disperse dyes were recorded between 320 and 680 nm. A modified changeable size moving window partial least squares (CSMWPLS) and searching combination moving window partial least squares (SCMWPLS) were proposed to search for an optimized spectral interval and an optimized combination of spectral regions from informative regions obtained by MWPLSR. Different wavelength regions were selected by taking into account different spectral parameters including the starting wavelength, the ending wavelength and wavelength interval. It was found that wavelength selection improved the performance of the corresponding net analyte signal-partial least squares (NAS-PLS) model, in terms of root mean square error (RMSE), compared with the results obtained using whole spectra or direct combination of informative regions for each dye. The importance of calibration design was also investigated by calculating the prediction and validation errors. The influence of using independent validation sets were emphasized. The proposed calibration method gave better results in combination and informative spectral regions for determination of the six disperse dyes without prior separation.

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