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1.
Molecules ; 26(20)2021 Oct 14.
Artículo en Inglés | MEDLINE | ID: mdl-34684768

RESUMEN

The enrichment of commonly consumed foods with bioactive components might be helpful in promoting health and reducing the risk of disease, so the enrichment of probiotic fermented milk with vitamin C can be considered appropriate. The effect of vitamin C addition depends on the source of origin (rosehip, acerola and ascorbic acid in powder form) on the growth and survival of Lactobacillus rhamnosus and the quality of fermented milk on the 1st and 21st day of storage was analyzed. The pH, total acidity, vitamin C, syneresis, color, texture profile and numbers of bacterial cells in fermented milk were determined. The organoleptic evaluation was also performed. The degradation of vitamin C in milk was shown to depend on its source. The lowest reduction of vitamin C was determined in milk with rosehip. The least stable was vitamin C naturally found in control milk. The addition of rosehip and acerola decreased syneresis and lightness of milk color, increasing the yellow and red color proportion. In contrast, milk with ascorbic acid was the lightest during the whole experimental period and was characterized by a very soft gel. The growth of Lactobacillus rhamnosus during fermentation was most positively affected by the addition of rosehip. However, the best survival of Lactobacillus rhamnosus was demonstrated in milk with acerola. On the 21st day of storage, the number of L. rhamnosus cells in the control milk and the milk with vitamin C was >8 log cfu g-1, so these milks met the criterion of therapeutic minimum. According to the assessors, the taste and odor contributed by the addition of rosehip was the most intense of all the vitamin C sources used in the study.


Asunto(s)
Ácido Ascórbico/administración & dosificación , Productos Lácteos Cultivados/análisis , Productos Lácteos Cultivados/microbiología , Lacticaseibacillus rhamnosus/metabolismo , Probióticos/metabolismo , Animales , Ácido Ascórbico/aislamiento & purificación , Estabilidad de Medicamentos , Fermentación , Almacenamiento de Alimentos , Humanos , Concentración de Iones de Hidrógeno , Malpighiaceae/química , Odorantes , Polvos , Rosa/química , Gusto
2.
Molecules ; 26(15)2021 Jul 28.
Artículo en Inglés | MEDLINE | ID: mdl-34361724

RESUMEN

Orchids are rich treasure troves of various important phytomolecules. Among the various medicinal orchids, Ansellia africana stands out prominently in the preparing of various herbal medicines due to its high therapeutic importance. The nodal explants of A. africana were sampled from asymbiotically germinated seedlings on basal Murashige and Skoog (MS) medium and were micropropagated in MS medium supplemented with 3% sucrose and 10 µM meta topolin (mT) + 5 µM naphthalene acetic acid (NAA) +15 µM indole butyric acid (IBA) + 30 µM phloroglucinol (PG). In the present study, the essential oil was extracted by hydrodistillation and the oleoresins by the solvent extraction method from the micropropagated A. africana. The essential oil and the oleoresins were analysed by Gas Chromatography (GC) and GC/MS (Mass spectrometry). A total of 84 compounds were identified. The most predominant components among them were linoleic acid (18.42%), l-ascorbyl 2,6-dipalmitate (11.50%), linolenic acid (10.98%) and p-cresol (9.99%) in the essential oil; and eicosane (26.34%), n-butyl acetate (21.13%), heptadecane (16.48%) and 2-pentanone, 4-hydroxy-4-methyl (11.13%) were detected in the acetone extract; heptadecane (9.40%), heneicosane (9.45%), eicosane (6.40%), n-butyl acetate (14.34%) and styrene (22.20%) were identified and quantified in the ethyl acetate extract. The cytotoxic activity of essential oil and oleoresins of micropropagated A. africana was evaluated by MTT (3-(4,5-dimethylthiazol-2-yl)-2,5-diphenyltetrazolium Bromide) assay on Vero cells compared to the standard drug doxorubicin chloride. The present research contains primary information about the therapeutic utility of the essential oil and oleoresins of A. africana with a promising future research potential of qualitative and quantitative improvement through synchronised use of biotechnological techniques.


Asunto(s)
Citotoxinas/aislamiento & purificación , Aceites Volátiles/aislamiento & purificación , Orchidaceae/química , Extractos Vegetales/aislamiento & purificación , Plantones/química , Acrilatos/aislamiento & purificación , Alcanos/aislamiento & purificación , Animales , Ácido Ascórbico/aislamiento & purificación , Supervivencia Celular/efectos de los fármacos , Chlorocebus aethiops , Cresoles/aislamiento & purificación , Medios de Cultivo/química , Medios de Cultivo/farmacología , Citotoxinas/farmacología , Cromatografía de Gases y Espectrometría de Masas , Hidroponía/métodos , Ácido Linoleico/aislamiento & purificación , Extracción Líquido-Líquido/métodos , Aceites Volátiles/farmacología , Orchidaceae/metabolismo , Palmitatos/aislamiento & purificación , Pentanoles/aislamiento & purificación , Pentanonas/aislamiento & purificación , Extractos Vegetales/farmacología , Plantas Medicinales , Plantones/metabolismo , Sudáfrica , Estireno/aislamiento & purificación , Células Vero , Ácido alfa-Linolénico/aislamiento & purificación
3.
Molecules ; 26(15)2021 Jul 29.
Artículo en Inglés | MEDLINE | ID: mdl-34361729

RESUMEN

Tyrosinase (TYR) is a type III copper oxidase present in fungi, plants and animals. The inhibitor of human TYR plays a vital role in pharmaceutical and cosmetic fields by preventing synthesis of melanin in the skin. To search for an effective TYR inhibitor from various plant extracts, a kinetic study of TYR inhibition was performed with mushroom TYR. Among Panax ginseng, Alpinia galanga, Vitis vinifera and Moringa oleifera, the extracts of V. vinifera seed, A. galanga rhizome and M. oleifera leaf reversibly inhibited TYR diphenolase activity with IC50 values of 94.8 ± 0.2 µg/mL, 105.4 ± 0.2 µg/mL and 121.3 ± 0.4 µg/mL, respectively. Under the same conditions, the IC50 values of the representative TYR inhibitors of ascorbic acid and kojic acid were found at 235.7 ± 1.0 and 192.3 ± 0.4 µg/mL, respectively. An inhibition kinetics study demonstrated mixed-type inhibition of TYR diphenolase by A. galanga and V. vinifera, whereas a rare uncompetitive inhibition pattern was found from M. oleifera with an inhibition constant of Kii 73 µg/mL. Phytochemical investigation by HPLC-MS proposed luteolin as a specific TYR diphenolase ES complex inhibitor, which was confirmed by the inhibition kinetics of luteolin. The results clearly showed that studying TYR inhibition kinetics with plant extract mixtures can be utilized for the screening of specific TYR inhibitors.


Asunto(s)
Inhibidores Enzimáticos/farmacología , Proteínas Fúngicas/antagonistas & inhibidores , Luteolina/farmacología , Monofenol Monooxigenasa/antagonistas & inhibidores , Moringa oleifera/química , Agaricales/química , Agaricales/enzimología , Alpinia/química , Ácido Ascórbico/química , Ácido Ascórbico/aislamiento & purificación , Ácido Ascórbico/farmacología , Pruebas de Enzimas , Inhibidores Enzimáticos/química , Proteínas Fúngicas/aislamiento & purificación , Ensayos Analíticos de Alto Rendimiento , Concentración 50 Inhibidora , Cinética , Luteolina/química , Luteolina/aislamiento & purificación , Monofenol Monooxigenasa/aislamiento & purificación , Panax/química , Extractos Vegetales/química , Extractos Vegetales/farmacología , Hojas de la Planta/química , Pironas/química , Pironas/aislamiento & purificación , Pironas/farmacología , Rizoma/química , Semillas/química , Vitis/química
4.
Molecules ; 25(15)2020 Aug 03.
Artículo en Inglés | MEDLINE | ID: mdl-32756431

RESUMEN

The aim of the study was to investigate the effect of high-pressure processing (HPP) and thermal processing (TP) on the bioaccessibility of vitamin C and anthocyanins as well as changes in the antioxidant capacity (AC) using ABTS+• and DPPH• tests on blackcurrant (Ribes nigrum L.) puree during the steps in the digestive process. The puree was subjected to HPP at 200, 400, and 600 MPa for 5 min (room temperature) or TP at 85 °C for 10 min. The controls were untreated puree (P) and fruit crushed in a mortar (M). All the samples were digested in a static in vitro digestion model, including the mouth, stomach, and small intestine, and subjected to dialysis. The vitamin C, anthocyanin, and antioxidant capacity were monitored at each step of the digestion process. The potential bioaccessibility of the antioxidants studied was calculated in relation to the undigested sample. TP and HPP enabled a high content of vitamin C, anthocyanins, and AC to be maintained. After simulated digestion in the small intestine, a significant decrease was observed in the vitamin C and anthocyanins (approximately 98%) content. However, a high stability (approximately 70%) of both compounds was noted at the gastric stage. HPP and TP significantly affected the potential bioaccessibility of vitamin C and anthocyanins, although the bioaccessibility of both compounds in the samples treated using HPP was higher than when using TP. Moreover, the potential bioaccessibility of vitamin C after HPP treatment (400 and 600 MPa) was higher than the bioaccessibility calculated for the M and P control samples. TP and HPP treatment negatively affected anthocyanin bioaccessibility after dialysis. The most favorable pressure was 400 MPa, as it allowed maintaining the best antioxidant activity after digestion.


Asunto(s)
Antioxidantes/química , Ribes/química , Antocianinas/análisis , Antocianinas/aislamiento & purificación , Ácido Ascórbico/análisis , Ácido Ascórbico/aislamiento & purificación , Cromatografía Líquida de Alta Presión , Digestión , Frutas/química , Frutas/metabolismo , Presión Hidrostática , Ribes/metabolismo , Espectrofotometría , Temperatura
5.
Molecules ; 25(7)2020 Mar 29.
Artículo en Inglés | MEDLINE | ID: mdl-32235298

RESUMEN

Girardinia diversifolia, also known as Himalayan nettle, is a perennial herb used in Nepal to make fiber as well as in traditional medicine for the treatment of several diseases. To date, phytochemical studies and biological assays on this plant are scarce. Thus, in the present work, the G. diversifolia extracts have been evaluated for their potential pharmaceutical, cosmetic and nutraceutical uses. For this purpose, detailed phytochemical analyses were performed, evidencing the presence of phytosterols, fatty acids, carotenoids, polyphenols and saponins. The most abundant secondary metabolites were ß- and γ-sitosterol (11 and 9% dw, respectively), and trans syringin (0.5 mg/g) was the most abundant phenolic. Fatty acids with an abundant portion of unsaturated derivatives (linoleic and linolenic acid at 22.0 and 9.7 mg/g respectively), vitamin C (2.9 mg/g) and vitamin B2 (0.12 mg/g) were also present. The antioxidant activity was moderate while a significant ability to inhibit acetylcholinesterase (AChE), butyrilcholinesterase (BuChE), tyrosinase, α-amylase and α-glucosidase was observed. A cytotoxic effect was observed on human ovarian, pancreatic and hepatic cancer cell lines. The effect in hepatocarcinoma cells was associated to a downregulation of the low-density lipoprotein receptor (LDLR), a pivotal regulator of cellular cholesterol homeostasis. These data show the potential usefulness of this species for possible applications in pharmaceuticals, nutraceuticals and cosmetics.


Asunto(s)
Anticolesterolemiantes/aislamiento & purificación , Antioxidantes/aislamiento & purificación , Citotoxinas/aislamiento & purificación , Inhibidores Enzimáticos/aislamiento & purificación , Fitoquímicos/aislamiento & purificación , Urticaceae/química , Anticolesterolemiantes/farmacología , Antioxidantes/farmacología , Ácido Ascórbico/aislamiento & purificación , Ácido Ascórbico/farmacología , Carotenoides/aislamiento & purificación , Carotenoides/farmacología , Línea Celular Tumoral , Supervivencia Celular/efectos de los fármacos , Citotoxinas/farmacología , Inhibidores Enzimáticos/farmacología , Ácidos Grasos/aislamiento & purificación , Ácidos Grasos/farmacología , Glucósidos/aislamiento & purificación , Glucósidos/farmacología , Humanos , Fenilpropionatos/aislamiento & purificación , Fenilpropionatos/farmacología , Fitoquímicos/farmacología , Fitosteroles/aislamiento & purificación , Fitosteroles/farmacología , Extractos Vegetales/química , Polifenoles/aislamiento & purificación , Polifenoles/farmacología , Receptores de LDL/antagonistas & inhibidores , Receptores de LDL/genética , Receptores de LDL/metabolismo , Riboflavina/aislamiento & purificación , Riboflavina/farmacología , Saponinas/aislamiento & purificación , Saponinas/farmacología , Sitoesteroles/aislamiento & purificación , Sitoesteroles/farmacología
6.
Food Sci Technol Int ; 26(1): 3-10, 2020 Jan.
Artículo en Inglés | MEDLINE | ID: mdl-31366240

RESUMEN

The aim of this study was to investigate the hurdle effect of combining atmospheric cold plasma (ACP) with hydrothermal treatment on ascorbic acid, individual polyphenolic compounds, total phenolic content, and microbial inactivation of strawberry juice. Strawberry juice was treated with ACP for 10 and 15 min using dielectric barrier discharge at 60 kV with the input voltage of 260 V. The ascorbic acid concentration was retained maximum only in ACP treatment followed by ACP + hydrothermal treatment. Furthermore, ACP treatment for 10 min coupled with hydrothermal treatment resulted in the higher concentration of gallic acid, epigallocatechin, phloretin, naringin, hyprin, and 4-O-caffeoylquinic acid with respect to control (p < 0.05). In addition, ACP treatment for 10 min at 60 kV in combination with hydrothermal treatment resulted in increased total phenolic content (p < 0.05). Moreover, a 2-log microbial reduction was found in processed strawberry juice with ACP coupled-hydrothermal treatment in comparison to control juice (p < 0.05). Therefore, ACP treatment of 10 min followed by hydrothermal treatment was found to be advantageous processing for strawberry juice to retain nutritional quality and decrease microbial load. Moreover, further optimization of ACP or hydrothermal processing with utilization of preservatives could be achieved for desired microbial inactivation for an industrial process.


Asunto(s)
Fragaria , Jugos de Frutas y Vegetales , Viabilidad Microbiana , Gases em Plasma/farmacología , Polifenoles/análisis , Ácido Ascórbico/análisis , Ácido Ascórbico/aislamiento & purificación , Fragaria/química , Fragaria/microbiología , Jugos de Frutas y Vegetales/análisis , Jugos de Frutas y Vegetales/microbiología , Calor , Viabilidad Microbiana/efectos de los fármacos , Viabilidad Microbiana/efectos de la radiación , Polifenoles/aislamiento & purificación
7.
Food Chem ; 307: 125531, 2020 Mar 01.
Artículo en Inglés | MEDLINE | ID: mdl-31644979

RESUMEN

In the present study, submicrometer flow-through silica microspheres (Sub-FTSiO2) was for the first time obtained via a suspension polymerization method coupled with sol-gel transition and phase separation. The Sub-FTSiO2 was characteristic of rich mesopores, penetrable macropores and small particle size, which would be beneficial to fast mass transfer, low column backpressure and high column efficiency. It was directly used as the hydrophilic interaction liquid chromatographic (HILIC) stationary phase, and the fast separation of seven water-soluble vitamins in 2.2 min was realized. The proposed method was successfully applied to the determination of water-soluble vitamins in two functional beverages on the market. The prepared Sub-FTSiO2 was well demonstrated for fast HILIC, and would be potential as the stationary phase matrix for fast liquid chromatography in diverse separation modes.


Asunto(s)
Cromatografía Liquida/métodos , Microesferas , Dióxido de Silicio/química , Vitaminas/aislamiento & purificación , Ácido Ascórbico/aislamiento & purificación , Interacciones Hidrofóbicas e Hidrofílicas , Complejo Vitamínico B/aislamiento & purificación , Vitaminas/química , Agua/química
8.
Sensors (Basel) ; 19(15)2019 Jul 26.
Artículo en Inglés | MEDLINE | ID: mdl-31357396

RESUMEN

In the present work, ternary mixtures of Acetaminophen, Ascorbic acid and Uric acid were resolved using the Electronic tongue (ET) principle and Cyclic voltammetry (CV) technique. The screen-printed integrated electrode array having differentiated response for the three oxidizable compounds was formed by Graphite, Prussian blue (PB), Cobalt (II) phthalocyanine (CoPc) and Copper oxide (II) (CuO) ink-modified carbon electrodes. A set of samples, ranging from 0 to 500 µmol·L-1, was prepared, using a tilted (33) factorial design in order to build the quantitative response model. Subsequently, the model performance was evaluated with an external subset of samples defined randomly along the experimental domain. Partial Least Squares Regression (PLS) was employed to construct the quantitative model. Finally, the model successfully predicted the concentration of the three compounds with a normalized root mean square error (NRMSE) of 1.00 and 0.99 for the training and test subsets, respectively, and R2 ≥ 0.762 for the obtained vs. expected comparison graphs. In this way, a screen-printed integrated electrode platform can be successfully used for voltammetric ET applications.


Asunto(s)
Acetaminofén/aislamiento & purificación , Ácido Ascórbico/aislamiento & purificación , Técnicas Biosensibles , Ácido Úrico/aislamiento & purificación , Acetaminofén/química , Ácido Ascórbico/química , Cobre/química , Técnicas Electroquímicas/métodos , Electrodos , Nariz Electrónica , Ferrocianuros/química , Grafito/química , Humanos , Indoles/química , Compuestos Organometálicos/química , Ácido Úrico/química
9.
Sensors (Basel) ; 19(15)2019 Jul 26.
Artículo en Inglés | MEDLINE | ID: mdl-31357512

RESUMEN

By means of electrospinning with the thermal annealing process, we investigate a highly efficient sensing platform driven by a hierarchical hetero-nanostructure for the sensitive detection of biologically relevant molecules, consisting of single crystalline ruthenium dioxide nanorods (RuO2 NRs) directly grown on the surface of electrospun tungsten trioxide nanofibers (WO3 NFs). Electrochemical measurements reveal the enhanced electron transfer kinetics at the prepared RuO2 NRs-WO3 NFs hetero-nanostructures due to the incorporation of conductive RuO2 NRs nanostructures with a high surface area, resulting in improved relevant electrochemical sensing performances for detecting H2O2 and L-ascorbic acid with high sensitivity.


Asunto(s)
Ácido Ascórbico/aislamiento & purificación , Técnicas Biosensibles , Técnicas Electroquímicas , Peróxido de Hidrógeno/aislamiento & purificación , Ácido Ascórbico/química , Peróxido de Hidrógeno/química , Nanofibras/química , Nanoestructuras/química , Nanotubos/química , Óxidos/química , Compuestos de Rutenio/química , Tungsteno/química
10.
Biomed Res Int ; 2019: 4503450, 2019.
Artículo en Inglés | MEDLINE | ID: mdl-30881987

RESUMEN

The objective of this study was to evaluate the association between salivary 1,5-anhydroglucitol (AG), vitamins A (VA), C (VC), and E (VE), and caries risk in children. 100 healthy children aged between 6 and 13 years were divided into two equal groups of caries-free (DMFS/dmfs=0) and caries active (DMFS/dmfs>3). Unstimulated midmorning saliva was collected from all the children and the levels of salivary AG and vitamins A, C, and E were measured. Caries risk assessment was done using American Academy of Pediatric Dentistry Caries Assessment Tool. Analysis of salivary AG and vitamins was performed using a commercially available ELISA kit. Low levels of AG were present in caries active and high caries risk groups compared to caries-free and low/medium caries risk groups. This difference is statistically significant (p < 0.05). A strong negative correlation between AG and caries activity was observed in the caries active group. VA was not related to caries activity, while VC and VE displayed a statistically significant correlation (p < 0.05). Similarly, a strong negative correlation was observed between the levels of AG and high caries risk group. Salivary AG, VC, and VE together are related to caries risk in caries active children. These salivary parameters can act as indicator of caries status in children.


Asunto(s)
Ácido Ascórbico/metabolismo , Caries Dental/metabolismo , Vitamina A/metabolismo , Vitamina E/metabolismo , Adolescente , Ácido Ascórbico/aislamiento & purificación , Niño , Caries Dental/epidemiología , Caries Dental/patología , Desoxiglucosa/aislamiento & purificación , Desoxiglucosa/metabolismo , Femenino , Humanos , Masculino , Factores de Riesgo , Saliva/química , Saliva/metabolismo , Vitamina A/aislamiento & purificación , Vitamina E/aislamiento & purificación
11.
Water Environ Res ; 91(5): 455-461, 2019 May.
Artículo en Inglés | MEDLINE | ID: mdl-30740828

RESUMEN

Eutectic freeze crystallization was developed to recover sodium erythorbate (NaE) from wastewater at pHs 4.1, 5.3, and 6.5. Two substances (A and B) were sequentially recovered from the samples. The recovery rate of substance A was 2.06, 1.83, and 3.03 g/L at pHs 4.1, 5.3, and 6.5, respectively; while that of B was 5.51, 3.09, and 3.26 g/L at the corresponding pHs. The analysis results of the two recovered substances indicated that substance A was mostly Na2 SO4 ·10H2 O, while substance B was mainly NaE. Salt recovery was most successful at pH 4.1 with the purity of recovered NaE reaching 87.53 wt%. Moreover, the chemical oxygen demand and electric conductivity of the ice were far smaller than the initial wastewater. The concentration effect was minimal due to the formation of Na2 SO4 ·10H2 O and NaE crystals. This combined crystallization strategy can potentially become an economic technology to recover NaE from wastewater. Practitioner points Segregation of NaE and Na2 SO4 ·10H2 O during the freeze crystallization process. Recovering 5.53 kg NaE with the purity of 87.53 wt% from 1 m3 wastewater. Decreasing chemical oxygen demand and electric conductivity of wastewater through freeze crystallization technology.


Asunto(s)
Ácido Ascórbico/química , Ácido Ascórbico/aislamiento & purificación , Congelación , Aguas Residuales/química , Contaminantes Químicos del Agua/química , Contaminantes Químicos del Agua/aislamiento & purificación , Purificación del Agua/métodos , Cristalización , Concentración de Iones de Hidrógeno , Hielo/análisis , Factores de Tiempo
12.
Food Chem ; 272: 141-147, 2019 Jan 30.
Artículo en Inglés | MEDLINE | ID: mdl-30309524

RESUMEN

A rapid and portable analytical methodology has been developed for ascorbic acid (Vitamin C) quantification from aqueous samples using a spectrometric smartphone-based system for the first time. The method employs point-of-use approaches both for sample preparation and sample measurement, demonstrating the capability for mobile quality control of pharmaceutical and food products. Our approach utilizes an oxidation-reduction reaction between ascorbic acid and methylene blue, followed by a dispersive liquid-liquid microextraction (DLLME) to extract the aqueous-phase methylene blue into organic media. Then, a back-extraction procedure is employed to transfer the methylene blue to aqueous media, followed by analysis of the sample's absorption spectrum using the spectrometric smartphone-based system. The DLLME and back-extraction procedures are optimized by use of a two-step multivariate optimization strategy. Finally, vitamin C supplements and orange juice are used as real-world samples to assess the applicability of the smartphone-based method, which is successfully compared with the standard laboratory-based approach.


Asunto(s)
Ácido Ascórbico/análisis , Teléfono Inteligente , Análisis Espectral/métodos , Ácido Ascórbico/química , Ácido Ascórbico/aislamiento & purificación , Suplementos Dietéticos/análisis , Jugos de Frutas y Vegetales/análisis , Microextracción en Fase Líquida , Azul de Metileno/química , Sistemas de Atención de Punto , Agua/química
13.
Biosens Bioelectron ; 124-125: 191-198, 2019 Jan 15.
Artículo en Inglés | MEDLINE | ID: mdl-30388561

RESUMEN

In this work, Pt nanoparticles modified nanoporous AuSn(Pt@NP-AuSn) alloy on Ni buffered flexible carbon fiber paper (CFP) is fabricated by a simple replacement reaction in which NP-AuSn is fabricated by controllable dealloy of electrodeposited Au-Sn alloy films. The as prepared Pt@NP-AuSn/Ni/CFP possesses hierarchical pore structure, high specific surface area and excellent catalytic activity. Due to the bi-functions of both the large surface area of nanoporous metal and macroporous of carbon fiber paper facilitating mass transfer, the Pt@NP-AuSn/Ni/CFP shows high sensitivity of detecting ascorbic acid (AA), dopamine (DA) and uric acid (UA), with sensitivities of 0.14 µA µM-1 cm-2, 15.23 µA µM-1 cm-2, 0.28 µA µM-1 cm-2 under the concentration ranging from 200 to 2000 µM, 1-10 µM, and 25-800 µM for AA, DA and UA, respectively. Further, the Pt@NP-AuSn/Ni/CFP possesses long-term stability of sensing AA, DA and UA and presents great anti-interference towards a variety of common compounds in body fluid. All of these results manifest the Pt@NP-AuSn/Ni/CFP can be a promising candidate for the application of the electrochemical sensor for simultaneous detection of AA, DA and UA.


Asunto(s)
Ácido Ascórbico/aislamiento & purificación , Técnicas Biosensibles , Dopamina/aislamiento & purificación , Ácido Úrico/aislamiento & purificación , Ácido Ascórbico/química , Fibra de Carbono/química , Dopamina/química , Nanopartículas del Metal/química , Nanoporos , Platino (Metal)/química , Estaño/química , Ácido Úrico/química
14.
Food Chem ; 277: 698-705, 2019 Mar 30.
Artículo en Inglés | MEDLINE | ID: mdl-30502205

RESUMEN

In this study, we compared the antioxidant activity of ripe and unripe acerola extracts with synthetic antioxidants (BHA and BHT). This activity was assessed by classical approaches (DPPH and ABTS) and by an in vivo method using yeasts. Acerola extracts contain phenolic compounds and ascorbic acid that exhibit radical scavenger capacity and reducing power. The results obtained with yeasts revealed that the acerola extracts and BHT either acted as antioxidants or presented no activity depending on the nature of the oxidant molecule used. BHA decreased yeast resistance to oxidative treatments and also showed deleterious effects even when oxidative treatments were not applied. The unripe acerola was the most efficient antioxidant in the in vitro experiments but not necessarily in the in vivo assays, showing the weakness of in vitro systems in predicting antioxidant responses for biological purposes. BHA presented cell damaging effects even in the absence of oxidizing reagents.


Asunto(s)
Antioxidantes/química , Malpighiaceae/química , Extractos Vegetales/química , Saccharomyces cerevisiae/metabolismo , Antioxidantes/síntesis química , Antioxidantes/farmacología , Ácido Ascórbico/química , Ácido Ascórbico/aislamiento & purificación , Ácido Ascórbico/farmacología , Peróxido de Hidrógeno/farmacología , Malpighiaceae/metabolismo , Fenoles/química , Fenoles/aislamiento & purificación , Fenoles/farmacología , Extractos Vegetales/farmacología , Especies Reactivas de Oxígeno/metabolismo , Saccharomyces cerevisiae/efectos de los fármacos , Saccharomyces cerevisiae/crecimiento & desarrollo , Vitamina K 3/farmacología
15.
Biosens Bioelectron ; 127: 50-56, 2019 Feb 15.
Artículo en Inglés | MEDLINE | ID: mdl-30592993

RESUMEN

We report HRP-catalyzed polymerization of Tannic acid (TA) and application of the poly (Tannic acid) (p(TA)) as a versatile platform for covalent immobilization of biomolecules on various electrode surfaces based on electrochemical oxidation of the p(TA) and subsequent oxidative coupling reactions with the biomolecules. We also used this method for capturing cancer cells through a linker molecule, folic acid (FA). Furthermore, we have demonstrated that enhanced electrocatalytic activity of the p(TA)-modified surface could be used for simultaneous electrochemical determination of biologically important electroactive molecules such as ascorbic acid (AA), dopamine (DA), and uric acid (UA). This HRP-catalyzed polymerization of TA and p(TA)-mediated surface modification method can provide a simple and new framework to construct multifunctional platforms for covalent attachment of biomolecules and development of sensitive electrochemical sensing devices.


Asunto(s)
Ácido Ascórbico/aislamiento & purificación , Técnicas Biosensibles , Dopamina/aislamiento & purificación , Ácido Úrico/aislamiento & purificación , Ácido Ascórbico/química , Dopamina/química , Técnicas Electroquímicas , Humanos , Oxidación-Reducción , Polimerizacion , Taninos/química , Ácido Úrico/química
16.
Curr Pharm Biotechnol ; 19(11): 877-885, 2018.
Artículo en Inglés | MEDLINE | ID: mdl-30332948

RESUMEN

BACKGROUND: Exosome-like nanovesicles are biological nanostructures mediating cell-tocell communication and capable to load selected cargos also in the interaction among different species. OBJECTIVE: We aimed to explore the content of exosome-like nanovesicles derived from Citrus limon L. and to analyze the effects of their uptake on human cells. METHOD: We isolated exosome-like nanovesicles from Citrus limon L. juice (EXO-CLs) by differential centrifugation. EXO-CLs were analyzed for short RNA content by advanced sequencing technologies, and for ascorbic acid (vitamin C) and citrate content by enzymatic assays. EXO-CLs anti-oxidant and pro-differentiative potential was evaluated in vitro on mesenchymal stromal cells (MSC), a common tool for regenerative strategies for several human tissues. RESULTS: We showed that EXO-CLs carry detectable amounts of citrate and vitamin C and, although it was not possible to identify specific miRNAs, we detected short RNA sequences (20-30 bp) with unknown functions and with different distribution size in respect to whole Citrus limon L. juice. In vitro, EXO-CLs were uptaken by MSC and had a significant protective effect against oxidative stress. Furthermore, regarding the potential benefit for human bone health, we found that EXO-CLs modulate MSC differentiation versus the osteogenic lineage. CONCLUSION: We demonstrated that incubation with EXO-CLs exert antioxidant activity in human cells. This is most likely due to the direct delivery and uptake of micronutrients by human cells that are well preserved inside the nanovesicle membrane, including the unstable vitamin C. Based on our results, we speculate that fruit-derived nanovesicles have the potential to mediate interspecies influence after food intake.


Asunto(s)
Antioxidantes/farmacología , Citrus/química , Exosomas/química , Frutas/química , Células Madre Mesenquimatosas/efectos de los fármacos , Antioxidantes/aislamiento & purificación , Ácido Ascórbico/aislamiento & purificación , Ácido Ascórbico/farmacología , Diferenciación Celular/efectos de los fármacos , Humanos , Células Madre Mesenquimatosas/metabolismo , MicroARNs/metabolismo , Estrés Oxidativo/efectos de los fármacos
17.
Food Funct ; 9(5): 2942-2950, 2018 May 23.
Artículo en Inglés | MEDLINE | ID: mdl-29741189

RESUMEN

Extraction of nutrients from plants is an important unit operation in the food and biological industries. The target nutrient is usually spatially distributed throughout the plant tissue. The intact cell wall and adhering membranes are the main resistances to molecular diffusion. Therefore, disintegration of the intact structure, which in turn increases the permeability of adhering membranes, can significantly improve the nutrient extraction yield and efficiency. In this study, different physical treatments (homogenization, high pressure homogenization, and ball mill grinding) were applied to investigate their effects on the tissue microstructure and the release of vitamin C. The changes in the microstructure were reflected by LF-NMR based on T2 distribution, particle size distribution, and microscopy images. The extraction yield of vitamin C obtained by high-pressure homogenization was increased by 75.69% for floret and 28.84% for stalk, respectively, as compared to that obtained by mechanical homogenization. The degradation of vitamin C was significant due to prolonged operation of the ball mill grinding method although the integrity of the tissues was similar to that of the high-pressure homogenization-treated tissues. This study confirms that the degree of tissue disintegration has a positive correlation with the release of the nutrient (vitamin C) within a limited operating time. LF-NMR has been proven to be an effective method to study the impact of different physical treatments on the cellular structure integrity of plant-originated food materials.


Asunto(s)
Ácido Ascórbico/química , Brassica/química , Espectroscopía de Resonancia Magnética/métodos , Extractos Vegetales/química , Ácido Ascórbico/aislamiento & purificación , Manipulación de Alimentos , Espectroscopía de Resonancia Magnética/instrumentación , Extractos Vegetales/aislamiento & purificación
18.
Sci Rep ; 8(1): 7243, 2018 05 08.
Artículo en Inglés | MEDLINE | ID: mdl-29740145

RESUMEN

The influences of various factors, including the symbiosis established with the roots of specific tree species, on the production of volatiles in the fruiting bodies of Tuber magnatum have not been investigated yet. Volatiles in T. magnatum fruiting bodies were quantitatively and qualitatively determined by both PTR-MS and GC-MS in order to compare the accuracy of the two methods. An electronic nose was also used to characterize truffle samples. The influence of environmental changes on the antioxidant capabilities of fruiting bodies was also determined. Statistically significant differences were found between fruiting bodies with different origins. The relationship between the quality of white truffle fruiting bodies and their specific host plant is described along with an analysis of metabolites other than VOCs that have ecological roles. Our results indicate that the geographical origin (Italy and Istria) of the fruiting bodies is correlated with the quantity and quality of volatiles and various antioxidant metabolites. This is the first report characterizing antioxidant compounds other than VOCs in white truffles. The correlation between geographical origin and antioxidant contents suggests that these compounds may be useful for certifying the geographical origin of truffles.


Asunto(s)
Antioxidantes/aislamiento & purificación , Cuerpos Fructíferos de los Hongos/química , Saccharomycetales/química , Compuestos Orgánicos Volátiles/aislamiento & purificación , Antioxidantes/clasificación , Antioxidantes/metabolismo , Ácido Ascórbico/aislamiento & purificación , Ácido Ascórbico/metabolismo , Betulaceae/microbiología , Betulaceae/fisiología , Nariz Electrónica , Cuerpos Fructíferos de los Hongos/metabolismo , Cromatografía de Gases y Espectrometría de Masas , Geografía , Glutatión/aislamiento & purificación , Glutatión/metabolismo , Italia , Metaboloma , Análisis Multivariante , Populus/microbiología , Populus/fisiología , Quercus/microbiología , Quercus/fisiología , Saccharomycetales/metabolismo , Espectrometría de Masa por Láser de Matriz Asistida de Ionización Desorción , Simbiosis/fisiología , Compuestos Orgánicos Volátiles/clasificación , Compuestos Orgánicos Volátiles/metabolismo
19.
Biosens Bioelectron ; 109: 123-131, 2018 Jun 30.
Artículo en Inglés | MEDLINE | ID: mdl-29547773

RESUMEN

A new portable electrochemical sensor based on 4-aminobenzoic acid-modified herringbone carbon nanotubes (hCNTs-4ABA/Au-IDA) has been developed for the simultaneous determination of ascorbic acid (AA) and uric acid (UA) in physiological fluids. AA and UA were quantified by chronoamperometry at 0.1 and 0.32 V, respectively, in phosphate buffer solution (PBS 0.25 M, pH 7.0). Significant results were obtained for the separate quantification of AA and UA, with a limit of detection (LOD) of 0.65 µM for both analytes, and sensitivities of (9.0 ±â€¯0.4) A g-1 mM-1 and (8.8 ±â€¯0.3) A g-1 mM-1 for AA and UA, respectively. Repeatability was studied at 50 µM for AA and UA, providing relative standard deviations (RSD) lower than 9%. Additions of glucose, dopamine and epinephrine did not interfere with the AA and UA determination. Furthermore, UA did not interfere with AA determination at 0.1 V, although AA additions increased the current recorded at 0.32 V. The method has been successfully applied to human urine, perspiration and serum samples, without significant matrix effects, which allows for the use of an external calibration and the analysis of all the matrices investigated.


Asunto(s)
Ácido Ascórbico/aislamiento & purificación , Técnicas Biosensibles , Ácido Úrico/aislamiento & purificación , Ácido 4-Aminobenzoico/química , Ácido Ascórbico/química , Dopamina , Electroquímica , Humanos , Límite de Detección , Nanotubos de Carbono/química , Polímeros , Ácido Úrico/química
20.
Biosens Bioelectron ; 109: 237-245, 2018 Jun 30.
Artículo en Inglés | MEDLINE | ID: mdl-29571160

RESUMEN

A metal-free electrode using heteroatom-doped microporous carbon was fabricated for the ultrasensitive monitoring of mono-bioactive molecules and the selective signaling of dopamine (DA) secreted by living cells. The constructed electrode based on sulfur-doped microporous carbon (S-MC) shows a high surface area, a spherical construction, numerous carbon chain defects, and microporous structures, which are the key factors of the interactive signaling transducer, fast response, and active interfacial surfaces. The intrinsic features of S-MC with different %S-doping (S-MC-1, and S-MC-2) through the sp2-carbon chain create abundant catalytic active sites, facilitate molecular diffusion through the microporous structure, promote strong binding with the targeted molecules, and induce interactions at electrolyte-electrode interfaces. The S-MC-1 provides selective signaling in a tertiary mixture of DA, ascorbic acid (AA), and uric acid (UA) with a high sensitivity and a wide linear range of 0.01-5, 10-4000, and 1-2000 µM, respectively. The detection limits were set at 3 nM, 1.26 µM, and 0.23 µM for DA, AA, and UA respectively. The S-MC-1 demonstrated a selective screening of DA released from PC12 cells under a K+ ion- stimulator with high sensitivity and promoted high biocompatibility, low cytotoxicity, high stability, and reliable reproducibility (%RSD ranged from 1 to 2.7). Our findings indicated that the S-MC-1 can be utilized as an in-vitro model for simultaneously monitoring extracellular-DA secreted from living cells and sensing mono-bioactive molecules in biological samples.


Asunto(s)
Ácido Ascórbico/aislamiento & purificación , Técnicas Biosensibles , Dopamina/aislamiento & purificación , Ácido Úrico/aislamiento & purificación , Ácido Ascórbico/química , Carbono/química , Catálisis , Dopamina/química , Electroquímica , Límite de Detección , Azufre/química , Ácido Úrico/química
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