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1.
Molecules ; 27(2)2022 Jan 10.
Artículo en Inglés | MEDLINE | ID: mdl-35056747

RESUMEN

Ginkgo biloba is a popular medicinal plant widely used in numerous herbal products, including food supplements. Due to its popularity and growing economic value, G. biloba leaf extract has become the target of economically motivated adulterations. There are many reports about the poor quality of ginkgo products and their adulteration, mainly by adding flavonols, flavonol glycosides, or extracts from other plants. In this work, we developed an approach using two-trace two-dimensional correlation spectroscopy (2T2D COS) in UV-Vis range combined with multilinear principal component analysis (MPCA) to detect potential adulteration of twenty G. biloba food supplements. UV-Vis spectral data are obtained for 80% methanol and aqueous extracts in the range of 245-410 nm. Three series of two-dimensional correlation spectra were interpreted by visual inspection and using MPCA. The proposed relatively quick and straightforward approach successfully differentiated supplements adulterated with rutin or those lacking ginkgo leaf extract. Supporting information about adulteration was obtained from the difference between the DPPH radical scavenging capacity of both extracts and from chromatographic (HPLC-DAD) fingerprints of methanolic samples.


Asunto(s)
Suplementos Dietéticos/análisis , Contaminación de Alimentos/análisis , Ginkgo biloba/química , Espectrofotometría Ultravioleta/métodos , Quimioinformática/métodos , Cromatografía Líquida de Alta Presión , Cromatografía de Fase Inversa , Quempferoles/análisis , Polonia , Análisis de Componente Principal , Quercetina/análisis , Rutina/análisis
2.
Molecules ; 27(2)2022 Jan 12.
Artículo en Inglés | MEDLINE | ID: mdl-35056782

RESUMEN

Phenolic compounds in the fruit of American cranberry (Vaccinium macrocarpon Aiton) determine the antioxidant, anti-inflammatory, anticancer, and other biological effects. The berries are used in the production of medicinal preparations and food supplements, which highlights the importance of qualitative and quantitative analysis of phenolic compounds in cranberry fruit raw material. The aim of our study was to develop and validate an efficient, cost-effective, reproducible, and fast UPLC-DAD methodology for the evaluation of the qualitative and quantitative composition of phenolic compounds in raw material and preparations of American cranberry fruit. During the development of the methodology, chlorogenic acid and the following flavonols were identified in cranberry fruit samples: myricetin-3-galactoside, quercetin-3-galactoside, quercetin-3-glucoside, quercetin-3-α-L-arabinopyranoside, quercetin-3-α-L-arabinofuranoside, quercetin-3-rhamnoside, myricetin, and quercetin. The developed and optimized UPLC-DAD methodology was validated according to the guidelines of the International Council for Harmonization (ICH), evaluating the following parameters: range, specificity, linearity (R2 > 0.999), precision (%RSD < 2%), LOD (0.38-1.01 µg/mL), LOQ (0.54-3.06 µg/mL), and recovery (80-110%). The developed methodology was applied to evaluate the qualitative and quantitative composition of phenolic compounds in fruit samples of cranberry cultivars 'Baifay', 'Bergman', 'Prolific', and 'Searles', as well as 'Bain-MC' and 'BL-12' clones. In the tested samples, the majority (about 70%) of the identified flavonols were quercetin derivatives. The greatest amount of quercetin-3-galactoside (1035.35 ± 4.26 µg/g DW) was found in fruit samples of the 'Searles' cultivar, and the greatest amount of myricetin-3-galactoside (940.06 ± 24.91 µg/g DW) was detected in fruit samples of the 'Woolman' cultivar.


Asunto(s)
Cromatografía Líquida de Alta Presión/métodos , Frutas/química , Fenoles/análisis , Fenoles/química , Espectrofotometría Ultravioleta/métodos , Vaccinium macrocarpon/química , Ácido Clorogénico/análisis , Exactitud de los Datos , Flavonoles/análisis , Extractos Vegetales/análisis , Extractos Vegetales/química
3.
Molecules ; 26(20)2021 Oct 11.
Artículo en Inglés | MEDLINE | ID: mdl-34684721

RESUMEN

Green nanoparticle synthesis is an environmentally friendly approach that uses natural solvents. It is preferred over chemical and physical techniques due to the time and energy savings. This study aimed to synthesize zinc oxide nanoparticles (ZnO NPs) through a green method that used Phlomis leaf extract as an effective reducing agent. The synthesis and characterization of ZnO NPs were confirmed by UV-Vis spectrophotometry, Fourier Transform Infrared Spectroscopy (FTIR), X-ray Diffraction (XRD), Dynamic light scattering (DLS), Zeta potential, and Field Emission Scanning Electron Microscope (FESEM) techniques. In vitro cytotoxicity was determined in L929 normal fibroblast cells using MTT assay. The antibacterial activity of ZnO nanoparticles was investigated using a disk-diffusion method against S. aureus and E. coli, as well as minimum inhibitory concentration (MIC) and minimum bactericidal concentration (MBC) content concentrations. XRD results confirmed the nanoparticles' crystalline structure. Nanoparticle sizes were found to be around 79 nm by FESEM, whereas the hydrodynamic radius of nanoparticles was estimated to be around 165 ± 3 nm by DLS. FTIR spectra revealed the formation of ZnO bonding and surfactant molecule adsorption on the surface of ZnO NPs. It is interesting to observe that aqueous extracts of Phlomis leave plant are efficient reducing agents for green synthesis of ZnO NPs in vitro, with no cytotoxic effect on L929 normal cells and a significant impact on the bacteria tested.


Asunto(s)
Tecnología Química Verde/métodos , Nanopartículas del Metal/química , Phlomis/metabolismo , Antibacterianos/farmacología , Antiinfecciosos/farmacología , Bacterias/efectos de los fármacos , Pruebas de Sensibilidad Microbiana , Extractos Vegetales/química , Sustancias Reductoras/farmacología , Espectrometría por Rayos X/métodos , Espectrofotometría Ultravioleta/métodos , Espectroscopía Infrarroja por Transformada de Fourier/métodos , Difracción de Rayos X/métodos , Óxido de Zinc/química
4.
Biomarkers ; 26(7): 606-616, 2021 Nov.
Artículo en Inglés | MEDLINE | ID: mdl-34229545

RESUMEN

CONTEXT: Stomach ulcer is one of the most common gastrointestinal problems in the world. OBJECTIVE: This study aimed to isolate flavonoid compounds from methanol extract of the aerial parts of Stachytarpheta jamaicensis (L.) Vahl. and evaluate its protective and therapeutic effects against gastric ulcer. MATERIALS AND METHODS: Chromatographic techniques were used for the identification of the isolated compounds. To explore the effects of the plant extract, it was administrated by oral gavage for one week either before or post-ethanol ulcer induction. Ranitidine was also evaluated as a reference drug. Stomach pH, gastric juice volume, lesions number, glutathione, superoxide dismutase, malondialdehyde, succinate dehydrogenase, lactate dehydrogenase, acid phosphatase, Interleukin-10, intracellular adhesion molecule-1, prostaglandin E2, and total protein levels were estimated in gastric tissue. Stomach histopathological features were also monitored. RESULTS: Six flavonoid compounds were isolated, where five of them were isolated for the first time (vitexin, isovitexin, apigenin 7,4'-dimethyl ether, 5,7,2'-trimethoxyflavone, and scutellarein), while apigenin was previously reported. Treatment with plant extract recorded amelioration in all the biochemical parameters. CONCLUSION: The methanol extract of plant aerial parts had prophylactic and treatment effects against gastric ulcer in rats, where its treatment effect exceeded its protective role. The extract recorded anti-inflammatory, and antioxidant effects due to the presence of flavonoid compounds.


Asunto(s)
Antiulcerosos/farmacología , Flavonoides/farmacología , Úlcera Gástrica/prevención & control , Verbenaceae/química , Animales , Antiulcerosos/uso terapéutico , Biomarcadores/metabolismo , Espectroscopía de Resonancia Magnética con Carbono-13/métodos , Flavonoides/química , Flavonoides/aislamiento & purificación , Mucosa Gástrica/efectos de los fármacos , Mucosa Gástrica/enzimología , Mucosa Gástrica/patología , Mediadores de Inflamación/metabolismo , Masculino , Estructura Molecular , Estrés Oxidativo , Componentes Aéreos de las Plantas/química , Extractos Vegetales/farmacología , Extractos Vegetales/uso terapéutico , Espectroscopía de Protones por Resonancia Magnética/métodos , Ratas , Ratas Wistar , Espectrofotometría Ultravioleta/métodos
5.
Molecules ; 26(10)2021 May 19.
Artículo en Inglés | MEDLINE | ID: mdl-34069558

RESUMEN

Recently, the biosynthesis of zinc oxide nanoparticles (ZnO NPs) from crude extracts and phytochemicals has attracted much attention. Green synthesis of NPs is cost-effective, eco-friendly, and is a promising alternative for chemical synthesis. This study involves ZnO NPs synthesis using Rubus fairholmianus root extract (RE) as an efficient reducing agent. The UV spectrum of RE-ZnO NPs exhibited a peak at 357 nm due to intrinsic bandgap absorption and an XRD pattern that matches the ZnO crystal structure (JCPDS card no: 36-1451). The average particle size calculated from the Debye-Scherrer equation is 11.34 nm. SEM analysis showed that the RE-ZnO NPs spherical in shape with clusters (1-100 nm). The antibacterial activity of the NPs was tested against Staphylococcus aureus using agar well diffusion, minimum inhibitory concentration, and bacterial growth assay. The R. fairholmianus phytochemicals facilitate the synthesis of stable ZnO NPs and showed antibacterial activity.


Asunto(s)
Nanopartículas del Metal/química , Extractos Vegetales/farmacología , Raíces de Plantas/química , Rubus/química , Óxido de Zinc/química , Cristalografía por Rayos X , Pruebas de Sensibilidad Microbiana , Espectrofotometría Ultravioleta/métodos , Espectroscopía Infrarroja por Transformada de Fourier/métodos , Staphylococcus aureus/efectos de los fármacos
6.
Molecules ; 26(11)2021 May 21.
Artículo en Inglés | MEDLINE | ID: mdl-34063849

RESUMEN

Iron, one of the most common metals in the environment, plays a fundamental role in many biological as well as biogeochemical processes, which determine its availability in different oxidation states. Its relevance in environmental and industrial chemistry, human physiology, and many other fields has made it necessary to develop and optimize analysis techniques for accurate determination. Spectrophotometric methods are the most frequently applied in the analytical determination of iron in real samples. Taking advantage of the fact that desferrioxamine B, a trihydroxamic acid used since the 1970s in chelation therapy for iron overload treatment, forms a single stable 1:1 complex with iron in whichever oxidation state it can be found, a smart spectrophotometric method for the analytical determination of iron concentration was developed. In particular, the full compliance with the Lambert-Beer law, the range of iron concentration, the influence of pH, and the interference of other metal ions have been taken into account. The proposed method was validated in terms of LoD, LoQ, linearity, precision, and trueness, and has been applied for total iron determination in natural water certified material and in biological reference materials such as control human urine and control serum.


Asunto(s)
Deferoxamina/química , Quelantes del Hierro/química , Hierro/análisis , Calibración , Colorimetría/métodos , Humanos , Concentración de Iones de Hidrógeno , Hierro/orina , Ligandos , Límite de Detección , Espectrometría de Masas/métodos , Reproducibilidad de los Resultados , Espectrofotometría Atómica/métodos , Espectrofotometría Ultravioleta/métodos , Agua/química
7.
Sci Rep ; 11(1): 7020, 2021 03 29.
Artículo en Inglés | MEDLINE | ID: mdl-33782442

RESUMEN

Pigmentation, a process controlled by melanogenesis, plays a vital role in protecting the skin against harmful ultraviolet rays. The level of protection is compromised in case of hypopigmentation. This study aimed to evaluate an Aspalathus linearis extract, fractions and phytoconstituents, for their efficacy on melanogenesis stimulation. Fifteen compounds were kinetically assessed against tyrosinase; the rate-limiting enzyme of melanogenesis. Aspalathin and catechin significantly (p value < 0.001) increased the enzymatic rate, showing 50% stimulatory effects at 119.70 ± 2.06 µg/mL and 143.30 ± 2.74 µg/mL, respectively, by acting as subversive substrates. Five compounds inhibited the enzyme's activity, of which four exhibited competitive inhibition. To investigate the molecular interactions between the compounds and the active site, molecular docking was done, using tyrosinase (PBD: 2Y9X) and tyrosinase related protein 1 (PBD: 5M8P). All the compounds docked successfully with acceptable docking scores. Further quantitative structure-activity relationship analysis identified potential functional groups, linked to the specific activity. The crude extract, its fractions, and compounds exhibited low antiproliferative activity with 50% cell viability at concentrations higher than 100 µg/mL. Finally, both aspalathin and catechin exhibited a significant increase (4.5%) in melanin production at 119.82 µg/mL and 76.92 µg/mL, respectively. This is the first report of A. linearis' compounds on skin re-pigmentation.


Asunto(s)
Aspalathus/química , Melaninas/biosíntesis , Monofenol Monooxigenasa/efectos de los fármacos , Extractos Vegetales/farmacología , Cromatografía Liquida/métodos , Simulación por Computador , Humanos , Melanocitos/efectos de los fármacos , Simulación del Acoplamiento Molecular , Relación Estructura-Actividad Cuantitativa , Pigmentación de la Piel/efectos de los fármacos , Espectrofotometría Ultravioleta/métodos
8.
Poult Sci ; 100(2): 675-684, 2021 Feb.
Artículo en Inglés | MEDLINE | ID: mdl-33518121

RESUMEN

In the present study, 200 Brown commercial egg-type layers (60 wk old) were used to study the effects of different levels of ecofriendly synthesis of calcium (Ca) nanoparticles (0.0, 0.50, 1.0, and 1.5 g/kg diet) with biocompatible Sargassum latifolium algae extract (SL-CaNps) on exterior egg quality traits, electronic microscopic view of eggshells, Ca and phosphorus (P) retention, serum Ca and P concentrations, and the histology of the uterus. Hens fed with dietary SL-CaNps powder had higher egg weight and shell weight % values than those of the control group. All SL-CaNps treatment groups had the greatest values of shell weight per unit surface area and shell thickness. Dietary supplementation of SL-CaNps at graded levels up to 1.5 g/kg diet had higher serum Ca and inorganic P levels than that of the control. Laying hens fed with SL-CaNps-added diets had beneficial effects on shell ultrastructure in terms of well-developed palisade and mammillary layers. The numbers of apical cells along the branched tubular gland were greater in SL-CaNps-treated groups than those of control. Conclusively, supplementing SL-CaNps powder up to 1.5 g/kg to the diet of laying hens improved eggshell thickness, shell weight% and shell weight per unit surface and has no adverse effect on their eggshell quality or electronic microscopic view of their eggshell.


Asunto(s)
Calcio/administración & dosificación , Pollos/fisiología , Cáscara de Huevo/ultraestructura , Huevos/normas , Nanopartículas , Sargassum/química , Factores de Edad , Alimentación Animal/análisis , Animales , Pollos/anatomía & histología , Dieta/veterinaria , Suplementos Dietéticos , Femenino , Microscopía Electrónica de Rastreo/veterinaria , Microscopía Electrónica de Transmisión/veterinaria , Distribución Aleatoria , Espectrofotometría Ultravioleta/métodos , Espectrofotometría Ultravioleta/veterinaria
9.
Molecules ; 25(21)2020 Nov 06.
Artículo en Inglés | MEDLINE | ID: mdl-33171900

RESUMEN

Scopoletin has previously been reported as a biomarker for the standardization of Paederia foetida twigs. This study is the first report on the determination and quantification of scopoletin using quantitative nuclear magnetic resonance (qNMR) in the different extracts of Paederia foetida twigs. The validated qNMR method showed a good linearity (r2 = 0.9999), limit of detection (LOD) (0.009 mg/mL), and quantification (LOQ) (0.029 mg/mL), together with high stability (relative standard deviation (RSD) = 0.022%), high precision (RSD < 1%), and good recovery (94.08-108.45%). The quantification results of scopoletin concentration in chloroform extract using qNMR and microplate ultraviolet-visible (UV-vis) spectrophotometer was almost comparable. Therefore, the qNMR method is deemed accurate and reliable for quality control of Paederia foetida and other medicinal plants without extensive sample preparation.


Asunto(s)
Biomarcadores Farmacológicos/análisis , Espectroscopía de Resonancia Magnética/métodos , Rubiaceae/química , Escopoletina/análisis , Espectrofotometría Ultravioleta/métodos , Límite de Detección , Extractos Vegetales/análisis , Extractos Vegetales/química , Preparaciones de Plantas/análisis , Plantas Medicinales/química , Sensibilidad y Especificidad , Solventes/química
10.
Molecules ; 25(20)2020 Oct 13.
Artículo en Inglés | MEDLINE | ID: mdl-33066248

RESUMEN

Tea is an important beverage in humans' daily lives. For a long time, tea grade identification relied on sensory evaluation, which requires professional knowledge, so is difficult and troublesome for laypersons. Tea chemical component detection usually involves a series of procedures and multiple steps to obtain the final results. As such, a simple, rapid, and reliable method to judge the quality of tea is needed. Here, we propose a quick method that combines ultraviolet (UV) spectra and color difference to classify tea. The operations are simple and do not involve complex pretreatment. Each method requires only a few seconds for sample detection. In this study, famous Chinese green tea, Huangshan Maofeng, was selected. The traditional detection results of tea chemical components could not be used to directly determine tea grade. Then, digital instrument methods, UV spectrometry and colorimetry, were applied. The principal component analysis (PCA) plots of the single and combined signals of these two instruments showed that samples could be arranged according to grade. The combined signal PCA plot performed better with the sample grade descending in clockwise order. For grade prediction, the random forest (RF) model produced a better effect than the support vector machine (SVM) and the SVM + RF model. In the RF model, the training and testing accuracies of the combined signal were all 1. The grades of all samples were correctly predicted. From the above, the UV spectrum combined with color difference can be used to quickly and accurately classify the grade of Huangshan Maofeng tea. This method considerably increases the convenience of tea grade identification.


Asunto(s)
Análisis de los Alimentos/métodos , Espectrofotometría Ultravioleta/métodos , Té/química , Camellia sinensis/química , Color , Análisis de los Alimentos/estadística & datos numéricos , Humanos , Análisis de Componente Principal , Espectrofotometría Ultravioleta/estadística & datos numéricos , Máquina de Vectores de Soporte , Gusto
11.
Sci Rep ; 10(1): 13738, 2020 08 13.
Artículo en Inglés | MEDLINE | ID: mdl-32792661

RESUMEN

Selenium-doped nanostructure has been considered as an attractive approach to enhance the antibacterial activity of calcium phosphate (CaP) materials in diverse medical applications. In this study, the selenium-doped biphasic calcium phosphate nanoparticles (SeB-NPs) were first synthesized. Then, silver was in situ incorporated into SeB-NPs to obtain nanostructured composite nanoparticles (AgSeB-NPs). Both SeB-NPs and AgSeB-NPs were characterized by Fourier transform infrared spectroscopy (FT-IR), X-ray diffraction (XRD), ultraviolet-visible spectroscopy (UV-Vis), X-ray photoelectron spectroscopy (XPS), and Raman spectra. The results confirmed that the SeO32- was doped at the PO43- position and silver nanoparticles were deposited on the surface of SeB-NPs. Next, Transmission Electron Microscopy (TEM) analysis displayed that the prepared AgSeB-NPs had a needle-cluster-like morphology. CCK-8 analysis revealed SeB-NPs and AgSeB-NPs had good cytocompatibility with osteoblasts. The antibacterial activity of the prepared AgSeB-NPs was confirmed by using Gram-negative E. coli and Gram-positive S. aureus. The above results manifested the significance of the final AgSeB-NPs for biomedical applications.


Asunto(s)
Antibacterianos/farmacología , Hidroxiapatitas/química , Hidroxiapatitas/farmacología , Nanopartículas del Metal/química , Nanoestructuras/química , Selenio/química , Células Cultivadas , Escherichia coli/efectos de los fármacos , Humanos , Pruebas de Sensibilidad Microbiana/métodos , Microscopía Electrónica de Transmisión/métodos , Tamaño de la Partícula , Espectroscopía de Fotoelectrones/métodos , Plata/química , Espectrofotometría Ultravioleta/métodos , Espectroscopía Infrarroja por Transformada de Fourier/métodos , Staphylococcus aureus/efectos de los fármacos , Difracción de Rayos X/métodos
12.
Spectrochim Acta A Mol Biomol Spectrosc ; 221: 117166, 2019 Oct 05.
Artículo en Inglés | MEDLINE | ID: mdl-31163328

RESUMEN

The aim of our study is to develop a new vortex assisted-ionic liquid dispersive liquid-liquid microextraction (VA-IL-DLLM) method for preconcentration and determination of the quercetin in tea, honey, fruit juice and wine samples by spectrophotometry. The method is based on pH sensitive ion-pair formation between quercetin and rhodamine B at pH 6.5 by donor-acceptor mechanism, and then dispersion of the complex in the fine-drops of ionic liquid (IL). In this context, the effects of pH, concentrations of ion-pairing reagent, the IL, vortex time and dispersive solvent type on the preconcentration process of quercetin were investigated using a 2-level-5-factor central composite half fraction design (CCD) as experimental design for response surface methodology (RSM). Quantitative model was developed to determine the quercetin in food samples, and it is verified by analysis of variance (ANOVA) at a 95% confidence level (P < 0.05). Response surface plots and contour plots obtained by the model are used to determine the interactions of experimental variables. After the optimization, calibration graph was obtained between 35 and 750 µg L-1 with the detection limit of 10.2 µg L-1. The recovery and relative standard deviations (RSD%) were in range of 94-104%, and in range of 2.5-4.2%, respectively. The accuracy and precision of the method were tested by the experimental studies such as recoveries, intermediate precision, trueness and expanded uncertainty. A comparison of the current results to those reported for other studies is also presented.


Asunto(s)
Jugos de Frutas y Vegetales/análisis , Miel/análisis , Microextracción en Fase Líquida/métodos , Quercetina/análisis , Té/química , Vino/análisis , Análisis de Varianza , Artefactos , Análisis de los Alimentos/métodos , Concentración de Iones de Hidrógeno , Líquidos Iónicos/química , Límite de Detección , Microextracción en Fase Líquida/estadística & datos numéricos , Reproducibilidad de los Resultados , Espectrofotometría Ultravioleta/métodos
13.
Molecules ; 24(8)2019 Apr 13.
Artículo en Inglés | MEDLINE | ID: mdl-31013952

RESUMEN

Pyrethroid residues in traditional Chinese medicines have been a serious threat to the health and treatment of patients. However, because of the matrix complexity of traditional Chinese medicine, the detection of pyrethroid residues remains a challenge. Therefore, we developed a QuEChERS method coupled with high-performance liquid chromatography and ultraviolet detection (HPLC-UV) for the determination of pyrethroid pesticides in three kinds of traditional Chinese medicine oral liquid preparations, and we investigated and optimized the extraction conditions. The matrix effect was estimated in the organic solvent and the actual samples by comparing the slopes of calibration curves, and the results showed that the matrix effect is not significant when using the modified QuEChERS method. The pyrethroid pesticides could be completely separated in 30 min. The linear correlation coefficients were more than 0.999, and the recoveries of all the pyrethroid pesticides ranged from 87.2% to 104.8%. The intra-day precisions (n = 5) were 2.44-4.62%, and the inter-day precisions (n = 5) were 1.06-3.02%. Moreover, the limits of detection were in the range of 0.007-0.018 ng mL-1, while the limits of quantitation were in the range of 0.022-0.057 ng mL-1. This simple, low-cost, and highly sensitive analytical method can be a potential tool for the analysis of pyrethroid residues in traditional Chinese medicine oral liquid preparations.


Asunto(s)
Medicamentos Herbarios Chinos/análisis , Residuos de Plaguicidas/análisis , Piretrinas/análisis , Cromatografía Líquida de Alta Presión/métodos , Medicamentos Herbarios Chinos/química , Humanos , Espectrofotometría Ultravioleta/métodos
14.
J AOAC Int ; 102(4): 1091-1094, 2019 Jul 01.
Artículo en Inglés | MEDLINE | ID: mdl-30764897

RESUMEN

Background: Aloe vera polysaccharides are considered to be the primary active components that provide numerous anecdotal health benefits. Objective: Several analytical methods are currently being used to quantitate the acemannan content of aloe vera processed raw materials. Some involve the use of very expensive and intricate equipment that is not normally found in production facilities. This document describes a single-laboratory validation for a very simple and inexpensive method that will be supported by a future multi-laboratory validation determination. Methods: The acetyl groups on the acemannan are converted into a ferric-acetohydroxamic complex that is quantitated using a simple and inexpensive UV-Vis spectrophotometer at 540 nm. Results: The analytical range for this method is 0.03-100% acemannan in both liquid and powdered materials. The recovery rate were 98-105% for both liquid and powdered samples. The repeatability precision was <2% at a level close to the LOQ. Conclusions: The results met the Standard Method Performance Requirements set by the AOAC Stakeholder Panel on Dietary Supplements. Highlights: The AOAC Expert Review Panel approved the present method as AOAC Official First Action 2018.14.


Asunto(s)
Aloe/química , Mananos/análisis , Espectrofotometría Ultravioleta/métodos , Acetilación , Complejos de Coordinación/análisis , Hierro/química , Mananos/química
15.
Phytochem Anal ; 30(3): 364-372, 2019 May.
Artículo en Inglés | MEDLINE | ID: mdl-30648323

RESUMEN

INTRODUCTION: Galloylquinic acid derivatives and flavonoids are the main phenolic metabolites found in Copaifera langsdorffii leaves (Leguminosae, Detarioideae), a medicinal plant with potential therapeutic application in the treatment of kidney stones. The factors that affect metabolite production in this plant species are not well understood but may include environmental and genetic factors. OBJECTIVE: To quantify the variation in metabolite production over a 12-month period for 10 groups of C. langsdorffii cultivated under the same environmental conditions. METHODS: Copaifera langsdorffii seeds were collected from 10 different regions in southeast, Brazil and grown in the same field. HPLC-UV was used to quantify nine galloylquinic acid derivatives and two flavonoids in leaf samples from mature trees. Climate data for humidity, radiation, precipitation and temperature were provided by the National Institute of Meteorology, Brazil. Multivariate analyses were performed to correlate chemical and environmental variables. RESULTS: The overall effect of environmental factors on the production of phenolic metabolites was uniform among C. langsdorffii groups. Chemical variation between groups was present, but small, and probably due to differences in their genetics and physiology. Seasonal changes influenced the production of the major phenolic metabolites, with increases in temperature and radiation levels favouring metabolite production. CONCLUSION: When C. langsdorffii trees are cultivated in the same environment, the production of the major secondary metabolites found in their leaves is very similar quantitatively, varying based on geographic location of original population and seasonal changes. This favours the standardisation of plant raw material for the production of a phytomedicine.


Asunto(s)
Fabaceae/metabolismo , Fenoles/análisis , Hojas de la Planta/metabolismo , Cromatografía Líquida de Alta Presión/métodos , Geografía , Fenoles/metabolismo , Fenoles/normas , Estándares de Referencia , Estaciones del Año , Espectrofotometría Ultravioleta/métodos
16.
Anal Bioanal Chem ; 411(6): 1219-1228, 2019 Feb.
Artículo en Inglés | MEDLINE | ID: mdl-30617392

RESUMEN

A fully automated method for the determination of lovastatin in dietary supplements containing red yeast rice has been developed. It uses a sequential injection analysis system combined with solid-phase extraction applying highly selective molecularly imprinted polymer sorbent. A miniaturized column for on-line extraction was prepared by packing 4.5 mg of the sorbent in a 5.0 × 2.5-mm-i.d. cartridge, which was used in the flow manifold. Sequential injection analysis manifold enabled all steps of lovastatin extraction and continuous spectrophotometric detection at 240 nm. A limit of detection of 60 µg g-1, a limit of quantitation of 200 µg g-1, and a linear calibration range of 200-2000 µg g-1 were achieved. Intra-day and inter-day precision values (RSD) were ≤ 6.7% and ≤ 4.9%, respectively, and method recovery values of spiked red yeast rice extracts at 200, 1000, and 2000 µg g-1 concentration levels were 82.9, 95.2, and 87.7%. Our method was used for determination of lovastatin lactone in four dietary supplements containing red yeast rice as a natural source of lovastatin, also known as monacolin K. The extracted samples were subsequently analyzed by the reference UHPLC-MS/MS method. Statistical comparison of results (F test, t test, α = 0.05) obtained by both methods did not reveal significant difference. A substantial advantage of the new automated approach is high sample throughput thanks to the analysis time of 7.5 min, miniaturization via down-scaling the extraction column, and smaller sample and solvent consumption, as well as reduced generation of waste. Graphical abstract ᅟ.


Asunto(s)
Anticolesterolemiantes/análisis , Productos Biológicos/análisis , Suplementos Dietéticos/análisis , Lovastatina/análisis , Impresión Molecular/métodos , Extracción en Fase Sólida/métodos , Cromatografía Líquida de Alta Presión/instrumentación , Cromatografía Líquida de Alta Presión/métodos , Diseño de Equipo , Análisis de Inyección de Flujo/instrumentación , Análisis de Inyección de Flujo/métodos , Límite de Detección , Impresión Molecular/instrumentación , Polímeros/química , Extracción en Fase Sólida/instrumentación , Espectrofotometría Ultravioleta/instrumentación , Espectrofotometría Ultravioleta/métodos , Espectrometría de Masas en Tándem/instrumentación , Espectrometría de Masas en Tándem/métodos
17.
Spectrochim Acta A Mol Biomol Spectrosc ; 206: 491-497, 2019 Jan 05.
Artículo en Inglés | MEDLINE | ID: mdl-30176424

RESUMEN

Vitamin deficiency is a main cause of many disorders and diseases that cannot be treated without using dietary supplements and multivitamin medications. We present here a UV-spectrophotometric method for simultaneous assay of two of the widely used vitamins, thiamine hydrochloride (vitamin B1) and pyridoxine hydrochloride (vitamin B6). The method is based on H-point standard addition to estimate the vitamins under study in their pure solutions and multivitamin ampoules by measuring the absorption of the mixture at 283 and 298 nm allowing its application in quality control laboratories. The work summarizes the theoretical basis of the H-point standard addition method. Moreover, a guide for the selection of the two wavelengths at which the calibration curves are constructed is given in this investigation. The linear ranges of the calibration graphs are 6.75-67.5 and 2.06-20.56 µg/mL for thiamine and pyridoxine, respectively. Correlation coefficients (r2) were found to be 0.9990 and 0.9899 at 283 nm and 0.9855 and 0.9995 at 298 nm for vitamin B1 and vitamin B6, respectively. Oscillator strength (f), transition dipole moment (µ) and resonance energy (RN) were calculated. The method was successfully applied for dual determination of the vitamins in their pure solutions and multivitamin ampoules with recovery values ranging from 98.41 to 102.6 and from 95.39 to 104.9% for thiamine and pyridoxine, respectively. The accuracy and precision of the proposed method is obvious from the low relative standard deviation values which are not more than 1.19%.


Asunto(s)
Piridoxina/análisis , Espectrofotometría Ultravioleta/métodos , Tiamina/análisis , Límite de Detección , Modelos Lineales , Reproducibilidad de los Resultados
18.
Food Chem ; 273: 52-56, 2019 Feb 01.
Artículo en Inglés | MEDLINE | ID: mdl-30292374

RESUMEN

Thermal rice oil degradation was evaluated by UV-Vis and NIR in three-way arrays assembled with samples, different temperatures, and the absorbance at different wavelengths by applying PARAFAC chemometric method. The loadings matrix of the mode corresponding to the samples (scores) contains the information related to the samples. The loadings on the temperature mode resemble kinetics profiles. These profiles change with the nature of the component responsible for the factor and evolve with the heating temperature. The loadings on the spectral mode reveal the antioxidants γ-oryzanol and tocopherol, and oxidation products are the components responsible for the two factors. The results achieved showed that the antioxidants concentration decreases starting at 70 °C while oxidation products start to increase more pronounced after 90 °C. The proposed method is shown to be a simple and fast way to obtain information about the oxidative stability of rice oils.


Asunto(s)
Análisis de los Alimentos/estadística & datos numéricos , Oryza/química , Aceites de Plantas/análisis , Espectrofotometría Ultravioleta/métodos , Antioxidantes/análisis , Interpretación Estadística de Datos , Análisis de los Alimentos/métodos , Calefacción , Cinética , Oxidación-Reducción , Fenilpropionatos/análisis , Aceites de Plantas/química , Temperatura , Tocoferoles/análisis , Vitamina E/análisis
19.
Phytochem Anal ; 30(1): 14-25, 2019 Jan.
Artículo en Inglés | MEDLINE | ID: mdl-30252165

RESUMEN

INTRODUCTION: Artemisiae argyi Folium and Artemisiae lavandulaefoliae Folium, two morphologically similar herbal medicines derived from Artemisia genus. Although the two Artemisia herbs have been used as medicines for a long time in China, the study of their phytochemical and bioactive composition is limited. OBJECTIVE: To comprehensively compare and evaluate the composition of Artemisiae argyi Folium and Artemisiae lavandulaefoliae Folium, and find the chemical makers for quality evaluation of the two Artemisia herbal medicines. METHODOLOGY: Eight compounds including six phenolic acids and two flavonoids were assayed by a single reference standard for simultaneous determination of multi-components method using 3-caffeoylquinic acid as the reference standard. The quantitative data were further analysed by chemometric approaches to compare and distinguish the two herbal medicines. RESULTS: The credibility and feasibility of the single reference standard for simultaneous determination of the multi-components method were carefully validated. The validated method was applied to analyse 16 batches of Artemisiae argyi Folium and 10 batches of Artemisiae lavandulaefoliae Folium samples. The quantitative results showed that 3,5-di-O-caffeoylquinic acid was the most abundant constituent, and the contents of flavonoids were notably different between the two herbal medicines. The chemometric analysis results indicated the two flavonoids, jaceosidin and eupatilin could be used as chemical markers for quality evaluation of the two herbal medicines. CONCLUSION: The single reference standard for simultaneous determination of the multi-components method coupled with chemometrics analysis could be a well-acceptable strategy to compare and evaluate the quality of Artemisiae argyi Folium and Artemisiae lavandulaefoliae Folium.


Asunto(s)
Artemisia/química , Cromatografía Líquida de Alta Presión/métodos , Medicamentos Herbarios Chinos/química , Medicamentos Herbarios Chinos/normas , Espectrofotometría Ultravioleta/métodos , Artemisia/clasificación , Análisis por Conglomerados , Límite de Detección , Análisis de Componente Principal , Control de Calidad , Estándares de Referencia , Especificidad de la Especie , Compuestos Orgánicos Volátiles/análisis
20.
Phytochem Anal ; 30(2): 156-163, 2019 Mar.
Artículo en Inglés | MEDLINE | ID: mdl-30426588

RESUMEN

INTRODUCTION: In the present study, a green and efficient extraction method using deep eutectic solvents as extraction solvent was developed for extracting the four major active compounds narirutin, naringin, hesperidin and neohesperidin from Aurantii Fructus. METHODOLOGY: A series of tunable deep eutectic solvents were prepared and investigated by mixing choline chloride or betaine to different hydrogen-bond donors, and betaine/ethanediol was found to be the most suitable extraction solvent. To achieve the best extraction yield, the primary factors affecting the extraction efficiency, such as hydrogen-bond acceptor/hydrogen-bond donor ratio, water content in deep eutectic solvents, extraction temperature, solid/liquid ratio and extraction time, were investigated. RESULTS: The optimal extraction conditions were 40% of water in betaine/ethanediol (1:4) at 60°C for heated extraction of 30 min and solid/liquid ratio 1:100 g/mL. Under the optimum extraction condition, the extraction yields of narirutin, naringin, hesperidin, and neohesperidin were 8.39 ± 0.61, 83.98 ± 1.92, 3.03 ± 0.35 and 35.94 ± 0.63 mg/g, respectively, which were much higher than those of methanol as extraction solvent (5.5 ± 0.48, 64.23 ± 1.51, 2.16 ± 0.15 and 30.14 ± 0.62 mg/g). CONCLUSION: The present results showed that deep eutectic solvents could be promising green and efficient solvents for extraction of the bioactive ingredients from traditional Chinese medicine.


Asunto(s)
Disacáridos/aislamiento & purificación , Flavanonas/aislamiento & purificación , Tecnología Química Verde , Hesperidina/análogos & derivados , Hesperidina/aislamiento & purificación , Solventes/química , Cromatografía Líquida de Alta Presión/métodos , Disacáridos/normas , Flavanonas/normas , Hesperidina/normas , Enlace de Hidrógeno , Estándares de Referencia , Espectrofotometría Ultravioleta/métodos
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