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1.
Naturwissenschaften ; 106(5-6): 25, 2019 May 08.
Artículo en Inglés | MEDLINE | ID: mdl-31069518

RESUMEN

The main chemical composition of Sonoran propolis (SP), as well as its antiproliferative activity on cancer cells through apoptosis induction, has been reported. The chemical constitution of SP remained qualitatively similar throughout the year, whereas the antiproliferative effect on cancer cells exhibited significant differences amongst seasonal samples. The main goal of this study was to provide phytochemical and pharmacological evidence for the botanical source of SP and its antiproliferative constituents. A chemical comparative analysis of SP and plant resins of species found in the surrounding areas of the beehives was carried out by HPLC-UV-DAD, as well as by 1H NMR experiments. The antiproliferative activity on cancerous (M12.C3.F6, HeLa, A549, PC-3) and normal cell lines (L-929; ARPE-19) was assessed through MTT assays. Here, the main polyphenolic profile of SP resulted to be qualitatively similar to Populus fremontii resins (PFR). However, the antiproliferative activity of PFR on cancer cells did not consistently match that exhibited by SP throughout the year. Additionally, SP induced morphological modifications on treated cells characterised by elongation, similar to those induced by colchicine, and different to those observed with PFR treatment. These results suggest that P. fremontii is the main botanical source of SP along the year. Nevertheless, the antiproliferative constituents of SP that induce that characteristic morphological elongation on treated cells are not obtained from PFR. Moreover, the presence of kaempferol-3-methyl-ether in SP could point Ambrosia ambrosioides as a secondary plant source. In conclusion, SP is a bioactive poplar-type propolis from semi-arid zones, in which chemical compounds derived from other semi-arid plant sources than poplar contribute to its antiproliferative activity.


Asunto(s)
Própolis/química , Própolis/farmacología , Células A549 , Línea Celular Tumoral , Proliferación Celular/efectos de los fármacos , Clima Desértico , Células HeLa , Humanos , Populus/química
2.
Molecules ; 24(2)2019 Jan 15.
Artículo en Inglés | MEDLINE | ID: mdl-30650628

RESUMEN

Chestnut (Castanea sativa Miller.) burs (CSB) represent a solid waste produced during the edible fruit harvesting. Their usual disposal in the field increases the environmental and economic impact of the agricultural process. HPLC-UV-HRMS profiling revealed that CSB organic and aqueous extracts (CSB-M, CSB-H, CSB-A) contain several hydrolyzable tannins, mainly ellagitannins, and glycoside flavonols. Ellagic acid (EA) and chestanin are predominant components (5⁻79 and 1⁻13 mg/g dry extract, respectively). NMR analysis confirmed the chemical structures of the major constituents from CSB-M. The extracts displayed a significant scavenging activity against DPPH (EC50 12.64⁻24.94 µg/mL) and ABTS⁺ radicals (TEAC value 2.71⁻3.52 mM Trolox/mg extract). They were effective in inhibiting the mycelial growth (EC50 6.04⁻15.51 mg/mL) and spore germination (EC50 2.22⁻11.17 mg/mL) of Alternaria alternata and Fusarium solani. At the highest concentration, CSB-M was also active against Botrytis cinerea both in mycelium and spore form (EC50 64.98 and 16.33 mg/mL). The EA contributed to the antifungal activity of extracts (EC50 on spore germination 13.33⁻112.64 µg/mL). Our results can support the upgrading of chestnut burs from agricultural wastes to a resource of natural fungicides for managing fruit and vegetable diseases.


Asunto(s)
Fagaceae/química , Extractos Vegetales/química , Extractos Vegetales/farmacología , Antioxidantes/química , Antioxidantes/farmacología , Cromatografía Líquida de Alta Presión , Fagaceae/metabolismo , Flavonoides/química , Flavonoides/farmacología , Hongos/efectos de los fármacos , Fungicidas Industriales/farmacología , Taninos Hidrolizables/química , Taninos Hidrolizables/farmacología , Pruebas de Sensibilidad Microbiana , Estructura Molecular , Fitoquímicos/química , Fitoquímicos/farmacología , Metabolismo Secundario
3.
Electrophoresis ; 2018 May 18.
Artículo en Inglés | MEDLINE | ID: mdl-29775214

RESUMEN

Artichoke by-products are a suitable source of health-promoting ingredients for the production of dietary supplements and food additives. A pressurized hot water extraction (PHWE) was developed to recover caffeoylquinic acids (CQAs) and flavone glycosides (FLs) from agro-industrial artichoke by-products. The main factors influencing PHWE efficiency and CQA isomerization (temperature, numbers of cycles, modifier, and extraction time) were carefully studied and optimized by response surface design. The proposed PHWE procedure provides an exhaustive extraction of CQAs and FLs (recoveries: 93-105% and 90-105%) from artichoke external bracts and leaves of different cultivars (p > 0.05), without significant formation of artefacts generated by high temperatures. PHWE extracts showed CQA and FL levels (14-37 mg/g and 3-19 mg/g, respectively) comparable to commercial products and marked antioxidative effects (EC50 11-83 µg/mL) by cellular antioxidant activity assay in human hepatocarcinoma HepG2 cells. These results proved that PHWE is an excellent green technique to recover bioactive compounds from artichoke agro-industrial residues.

4.
Anal Bioanal Chem ; 407(10): 2899-911, 2015 Apr.
Artículo en Inglés | MEDLINE | ID: mdl-25694147

RESUMEN

According to current demands and future perspectives in food safety, this study reports a fast and fully automated analytical method for the simultaneous analysis of the mycotoxins with high toxicity and wide spread, aflatoxins (AFs) and ochratoxin A (OTA) in dried fruits, a high-risk foodstuff. The method is based on pressurized liquid extraction (PLE), with aqueous methanol (30%) at 110 °C, of the slurried dried fruit and online solid-phase extraction (online SPE) cleanup of the PLE extracts with a C18 cartridge. The purified sample was directly analysed by ultra-high-pressure liquid chromatography-tandem mass spectrometry (UHPLC-MS/MS) for sensitive and selective determination of AFs and OTA. The proposed analytical procedure was validated for different dried fruits (vine fruit, fig and apricot), providing method detection and quantification limits much lower than the AFs and OTA maximum levels imposed by EU regulation in dried fruit for direct human consumption. Also, recoveries (83-103%) and repeatability (RSD < 8, n = 3) meet the performance criteria required by EU regulation for the determination of the levels of mycotoxins in foodstuffs. The main advantage of the proposed method is full automation of the whole analytical procedure that reduces the time and cost of the analysis, sample manipulation and solvent consumption, enabling high-throughput analysis and highly accurate and precise results.


Asunto(s)
Aflatoxinas/análisis , Cromatografía Líquida de Alta Presión/métodos , Frutas/química , Ocratoxinas/análisis , Extracción en Fase Sólida/métodos , Espectrometría de Masas en Tándem/métodos , Automatización , Análisis de los Alimentos , Contaminación de Alimentos/análisis , Concentración de Iones de Hidrógeno , Temperatura
5.
Antioxidants (Basel) ; 13(1)2024 Jan 12.
Artículo en Inglés | MEDLINE | ID: mdl-38247517

RESUMEN

Calabrian Glycyrrhiza glabra is one of the most appreciated licorice varieties worldwide, and its leaves are emerging as a valuable source of bioactive compounds. Nevertheless, this biomass is usually discarded, and its valorization could contribute to boost the economic value of the licorice production chain. In this study, the effects of production area and harvest time on the specialized metabolite content of G. glabra leaves (GGL) and also the antioxidant and anti-aging properties are evaluated to explore the potential of this untapped resource and to select the most optimal harvesting practices. GGL exhibited high levels of specialized metabolites (4-30 g/100 g of dry leaf) and the most abundant ones are pinocembrin, prenylated flavanones (licoflavanone and glabranin), and prenylated dihydrostilbenes. Their levels and antioxidant capacity in extracts are influenced by both production area and harvest time, showing a decisive role on specialized metabolites accumulation. Interestingly, GGL extracts strongly attenuate the toxicity of α-synuclein, the intracellular reactive oxygen species (ROS) content, and cellular senescence on Saccharomyces cerevisiae expressing human α-synuclein model, showing great potential to prevent aging and age-related disorders. These results provide insights into the phytochemical dynamics of GGL, identifying the best harvesting site and period to obtain bioactive-rich sources with potential uses in the food, nutraceutical, and pharmaceutical sectors.

6.
Nat Prod Res ; : 1-14, 2024 Apr 01.
Artículo en Inglés | MEDLINE | ID: mdl-38557224

RESUMEN

The discovery of natural molecules with antimicrobial properties has become an urgent need for the global treatment of bacterium and virus infections. Cistus incanus, a Mediterranean shrub species, represents a valuable source of phytochemicals with an interesting wide-spectrum antimicrobial potential. In this study, we analysed the spectrum of molecules composing a commercial hydroalcoholic extract of C. incanus finding ellagitannins as the most abundant. The effect of the extract and its main constituents (gallic acid, ellagic acid and punicalin) was assessed as co-treatment during viral (HSV-1, HCoV-229E, SARS-CoV-2) and bacterial infection (Staphylococcus aureus and Escherichia coli) of cells and as pre-treatment before virus infections. The results indicated a remarkable antiviral activity of punicalin against SARS-CoV-2 by pre-treating both the viral and the host cells, and a major sensitivity of S. aureus to the C. incanus extract compared to E. coli. The present study highlights broad antimicrobial potential of C. incanus extract.

7.
Anal Bioanal Chem ; 405(26): 8645-52, 2013 Oct.
Artículo en Inglés | MEDLINE | ID: mdl-23942569

RESUMEN

A simple, rapid, and sensitive method based on simultaneous protein precipitation and extraction of aflatoxin M1 (AFM1) followed by dispersive liquid-liquid microextraction (DLLME) and ultrahigh pressure liquid chromatography tandem mass spectrometry (UHPLC-MS/MS) analysis was developed for the determination of AFM1 in milk samples. In order to precipitate the proteins and extract AFM1 from milk, a sample pretreatment using acetonitrile and NaCl as the extraction/denaturant solvent and salting-out agent, respectively, was optimised. Subsequently, the acetonitrile (upper) phase, containing AFM1, was used as the disperser solvent in DLLME, and extractant (chloroform) and water were added in turn to the extract to perform the DLLME process. The main parameters affecting the extraction efficiency of the whole analytical procedure, such as acetonitrile volume, amount of salt, type and volume of extractant and water volume, were carefully optimised by experimental design. Under optimum conditions, the developed method provides an enrichment factor of 33 and detection and quantification limits (0.6 and 2.0 ng kg(-1), respectively) below the maximum levels imposed by current regulations for AFM1 in milk and infant milk formulae. Recoveries (61.3-75.3%) and repeatability (RSD < 10, n = 3), tested in different types of milk at four AFM1 levels, met the performance criteria required by EC Regulation No. 401/2006. Moreover, the matrix effect on the signal intensity of the analyte was negligible. The proposed method provides a rapid extraction and an accurate determination of AFM1 in milk and formula milk using a simple and inexpensive sample preparation procedure.


Asunto(s)
Aflatoxina M1/análisis , Carcinógenos/análisis , Microextracción en Fase Líquida/métodos , Leche/química , Leche/microbiología , Espectrometría de Masas en Tándem/métodos , Animales , Aspergillus/química , Cromatografía Líquida de Alta Presión/economía , Cromatografía Líquida de Alta Presión/métodos , Humanos , Fórmulas Infantiles/química , Recién Nacido , Límite de Detección , Microextracción en Fase Líquida/economía , Espectrometría de Masas en Tándem/economía
8.
Food Chem ; 423: 136306, 2023 Oct 15.
Artículo en Inglés | MEDLINE | ID: mdl-37167673

RESUMEN

An analytical procedure for the screening of 118 pyrrolizidine alkaloids (PAs) was successfully validated and applied to their quantitative determination in food supplements, herbal infusions, honey, and teas. It provides the reliable analyte identification by high-resolution tandem mass spectrometry (HRMS/MS), the accurate determination of 21 regulated PAs, and broad contamination profiles. 10% of 281 analyzed samples resulted contaminated at levels above the maximum levels (MLs) of European legislation. The contamination of herbal infusions of mixed plants can represent a possible health concern (23%; mean of PA sum above ML). A high number of PAs not included in the regulation was detected in honey and herbal food supplements, but their contribution was only relevant to the overall level in honey. The results indicate the need to continue collecting contamination data in food supplements and infusions of mixed herbs and to expand the PA-pool to be monitored in honey and related products.


Asunto(s)
Miel , Alcaloides de Pirrolicidina , Tés de Hierbas , Alcaloides de Pirrolicidina/análisis , Miel/análisis , Contaminación de Alimentos/análisis , Cromatografía Liquida , Espectrometría de Masas en Tándem/métodos , Suplementos Dietéticos/análisis , Tés de Hierbas/análisis
9.
Food Chem ; 406: 135058, 2023 Apr 16.
Artículo en Inglés | MEDLINE | ID: mdl-36459797

RESUMEN

An analytical platform for the detection of pyrrolizidine alkaloids (PAs) in honey, pollen, teas, herbal infusions, and dietary supplements is proposed; it includes a wide-scope suspect screening method, based on a diagnostic product ion filtering strategy for the characterization of PAs, and a target screening and identification method for the high-throughput detection of 118 PAs of a high-resolution mass spectral library. Salting-out assisted liquid-liquid extraction of aqueous extracts combined to ultra-high performance liquid chromatography-high-resolution tandem mass spectrometry was employed. The limit of identification (0.6-30 µg kg-1) of 28 standards were fit-for-purpose in PA-monitoring applications, with a false negative rate <1.3 % at 4 µg L-1. The wide-scope suspect screening method allowed the tentative identification of 88 compounds. The screening of 282 commercial samples revealed a broad contamination of the studied matrices, demonstrating the effectiveness of the platform in detecting and identifying both target and untarget PAs.


Asunto(s)
Miel , Alcaloides de Pirrolicidina , Alcaloides de Pirrolicidina/análisis , Espectrometría de Masas en Tándem/métodos , Cromatografía Líquida de Alta Presión , Miel/análisis , Polen/química , Contaminación de Alimentos/análisis
10.
Biology (Basel) ; 12(6)2023 May 30.
Artículo en Inglés | MEDLINE | ID: mdl-37372075

RESUMEN

Dittrichia viscosa (L.) Greuter subsp. viscosa (Asteraceae) is a perennial species naturally distributed in arid and marginal areas whose agroecological cultivation could be a useful innovation to produce quality biomass to extract phenolic-rich phytochemical blends. Here, biomass-yield trends were profiled at different growth stages under direct cropping, and inflorescences, leaves, and stems were submitted to water extraction and hydrodistillation. Then, four extracts were investigated for their biological activities in invitro and in planta assays. Extracts inhibited cress (Lepidium sativum)- and radish (Raphanus sativus)-seed germination and root elongation. All samples showed dose-dependent antifungal activity in the plate experiments, inhibiting up to 65% of the growth of the fungal pathogen Alternaria alternata, a leaf-spot disease agent of baby spinach (Spinacea oleracea). However, only the extracts from dried green parts and fresh inflorescences at the highest concentration significantly reduced (54%) the extent of Alternaria necrosis on baby spinach. UHPLC-HRMS/MS analysis revealed that the main specialized metabolites of the extracts are caffeoyl quinic acids, methoxylated flavonoids, sesquiterpene compounds such as tomentosin, and dicarboxylic acids, which may explain the observed bioactivity. Plant extracts obtained through sustainable methodology can be effective in biological agricultural applications.

11.
Heliyon ; 9(8): e18509, 2023 Aug.
Artículo en Inglés | MEDLINE | ID: mdl-37520973

RESUMEN

The popularity and number of dietary supplements on the health market have experienced an unprecedented boost in recent years. Simultaneously, their increased use has been accompanied by an increase in acute intoxication cases linked to the adulteration of these products with illicit and undeclared substances. In this study, a SERS-based screening methodology was developed to rapidly detect illegally added pharmaceutically active substances to dietary supplements. A portable analyzer and silver printed-SERS substrates were used to enhance the signal, requiring less than 20 min of sample preparation prior to the analysis. The method was successful in the qualitative identification of eleven out of twenty-three illicit adulterants in the dietary supplements; it could detect the target compounds at realistic adulteration levels (0.1-5.0% w/w), demonstrating the potential of SERS-based methodologies for forensic rapid screening applications. The developed method is quick, easy to use, requires no skilled technicians and little sample preparation, and allows in-situ analyses. For these reasons, it is suitable for quick screening to be performed by inspectors at customs. Moreover, the low specificity of spectroscopic methods, to which SERS belongs, would benefit the detection of newly synthesized analogues of the target adulterants, which would otherwise be more difficult using common mass spectrometry methods in absence of reference standards.

12.
Phytochemistry ; 203: 113415, 2022 Nov.
Artículo en Inglés | MEDLINE | ID: mdl-36049527

RESUMEN

The chemical composition and the antioxidant potential of Ecuadorian propolis samples (n = 19) collected in different provinces were investigated. HPLC-DAD-ESI/MSn and GC-EI-MS analysis of the methanol extracts enabled us to define six types of Ecuadorian propolis based on their secondary metabolite composition. 68 compounds were identified, 59 of which are reported for the first time in Ecuadorian propolis. The detected compounds include flavonoids, diterpenes, triterpenes, organic acid derivatives, alkylresorcinol derivatives and nemorosone. Plants belonging to genera Populus, Mangifera and Clusia seemed to be vegetable sources employed by bees to produce Ecuadorian propolis. Total phenolic content and antioxidant activity of propolis extracts were determined by the Folin-Ciocalteu assay and 2,2-diphenyl-1-picrylhydrazyl and ferric reducing/antioxidant potential assays, respectively. As expected, the variable chemical composition affected the differences in terms of antioxidant potential.


Asunto(s)
Diterpenos , Própolis , Triterpenos , Antioxidantes/química , Antioxidantes/farmacología , Cromatografía Líquida de Alta Presión , Diterpenos/química , Ecuador , Flavonoides/química , Metanol , Própolis/química , Triterpenos/análisis
13.
Anal Bioanal Chem ; 399(3): 1279-86, 2011 Jan.
Artículo en Inglés | MEDLINE | ID: mdl-21052643

RESUMEN

A novel approach for the rapid analysis of ochratoxin A (OTA) in wine samples is presented. Mycotoxin was extracted and concentrated from matrix using dispersive liquid-liquid microextraction (DLLME). The final extract is analyzed by liquid chromatography coupled to positive electrospray ionization tandem mass spectrometry employing [(2)H(5)]-ochratoxin A as internal standard. Some important parameters, such as the nature and volume of extraction solvent and dispersive solvent, and salt effect were investigated and optimized to achieve the best extraction efficiency and higher enrichment factor. Under the optimum extraction condition, the method provided enrichment factor around 80 times and showed a high sensitivity with method detection and quantification limits of 0.005 and 0.015 ng mL(-1), respectively. To test the accuracy of the analytical procedure, the optimized method was applied to the analysis of reference material T1755 (naturally contaminated white wine), with excellent results (accuracy of 103%) and showing a good precision with a CV (n = 6) of 5.8%. The proposed method, which is demonstrated to be quick, cheap, accurate and highly selective, was successfully applied to the analysis of Italian wines.


Asunto(s)
Fraccionamiento Químico/métodos , Deuterio/química , Ocratoxinas/análisis , Vino/análisis , Cromatografía Líquida de Alta Presión , Espectrometría de Masas en Tándem
14.
Can J Physiol Pharmacol ; 89(1): 50-7, 2011 Jan.
Artículo en Inglés | MEDLINE | ID: mdl-21186377

RESUMEN

Estrogen receptor (ER) antagonists have been widely used for breast cancer treatment; however, patients have increasingly shown resistance and sensitivity to the high toxicity of these drugs, and identification of novel targeted therapies is therefore required. To determine whether nemorosone, a polycyclic polyisoprenylated benzophenone isolated from floral resins of Clusia rosea Jacq. and Cuban propolis samples, exerts anticancer effects on human breast cancer cells, estrogen receptor positive (ERα+) MCF-7 and estrogen receptor negative (ERα-) MDA-MB-231 and LNCaP cells were used. Cells were treated with nemorosone alone or in association with 17ß-estradiol (E2) or an ER antagonist, ICI 182,780, a selective ER downregulator that completely abrogates estrogen-sensitive gene transcription. Nemorosone inhibited the cell viability of ERα+ but not of ERα- cells. In MCF-7, nemorosone induced inhibition of cell growth by blocking the cell cycle in the G0/G1 phase. Moreover, the expression of pERK1/2 and pAkt, considered to be hallmarks of the nongenomic estrogen signalling pathway, were reduced in MCF-7 cells treated with nemorosone. All these effects were enhanced by ICI 182,780. However, nemorosone was not able to interfere with E2-induced Ca²(+) release. These findings suggest that nemorosone may have therapeutic application in the treatment of breast cancer because of its activity on ERα.


Asunto(s)
Antineoplásicos Fitogénicos/toxicidad , Benzofenonas/toxicidad , Neoplasias de la Mama/patología , Clusia , Citotoxinas/toxicidad , Antineoplásicos Fitogénicos/aislamiento & purificación , Antineoplásicos Fitogénicos/uso terapéutico , Benzofenonas/aislamiento & purificación , Benzofenonas/uso terapéutico , Neoplasias de la Mama/tratamiento farmacológico , Señalización del Calcio/efectos de los fármacos , Señalización del Calcio/fisiología , Línea Celular Tumoral , Supervivencia Celular/efectos de los fármacos , Supervivencia Celular/fisiología , Citotoxinas/aislamiento & purificación , Citotoxinas/uso terapéutico , Femenino , Humanos , Extractos Vegetales/aislamiento & purificación , Extractos Vegetales/uso terapéutico , Extractos Vegetales/toxicidad
15.
J Chromatogr A ; 1651: 462295, 2021 Aug 16.
Artículo en Inglés | MEDLINE | ID: mdl-34118529

RESUMEN

Food processing industry is accompanied with the generation of a great production of wastes and by-products exceptionally rich in bioactive compounds (especially phenolics), with antioxidant activity. The recovery of these health molecules constitutes a key point for the valorization of by-products, with the possibility of creating new ingredients to be used for the formulation of food and cosmetic products. One of the main limitations to reuse by-products is linked to the high cost to obtain bioactive compounds, consequently in order to exploit these resources commercially valuable it is necessary to develop innovative, economic and environmentally friendly extraction strategies. These extraction methods should be able to reduce petroleum solvents, energy consumption and chemical wastes, protecting both environment and consumers and ensuring safe and high-quality final products. The purpose of this review is to summarize current knowledge and applications of the new extraction techniques such as supercritical fluid extraction, pressurized liquid extraction, ultrasound assisted extraction applied to polyphenols extraction from agricultural food by-products. Particular attention has been paid to theoretical background, highlighting mechanisms and safety precautions. Authors concluded that relevant results of these techniques represent an opportunity to industrial scale-up, improving the extraction yields, minimizing time, costs and environmental impact.


Asunto(s)
Agricultura , Tecnología Química Verde/métodos , Polifenoles/aislamiento & purificación , Cromatografía con Fluido Supercrítico , Extractos Vegetales/química , Ultrasonido
16.
Antioxidants (Basel) ; 10(2)2021 Feb 16.
Artículo en Inglés | MEDLINE | ID: mdl-33669451

RESUMEN

Food waste is a serious problem for food processing industries, especially when it represents a loss of a valuable source of nutrients and phytochemicals. Increasing consumer demand for processed food poses the problem of minimizing waste by conversion into useful products. In this regard, onion (Allium cepa) waste consisting mainly of onion skin is rich in bioactive phenolic compounds. Here, we characterized the flavonoid profiles and biological activities of onion skin wastes of two traditional varieties with protected geographical indication (PGI), the red "Rossa di Tropea" and the coppery "Ramata di Montoro", typically cultivated in a niche area in southern Italy. The phytochemical profiles of exhaustive extracts, characterized by ultra-high-performance liquid chromatography coupled with ultraviolet (UV) detection and high-resolution mass spectrometry, revealed that flavonols and anthocyanins were the characteristic metabolite classes of onion skins. Quercetin, quercetin glucosides and their dimer and trimer derivatives, and, among anthocyanins, cyanidin 3-glucoside, were the most abundant bioactive compounds. The potential of onion skins was evaluated by testing several biological activities: ABTS/oxygen radical absorbance capacity (ORAC) and in vitro alpha-glucosidase assays were performed to evaluate the antioxidant and anti-diabetic properties of the extracts and of their main compounds, respectively, and proliferative activity was evaluated by MTT assay on human fibroblasts. In the present study, by observing various biological properties of "Rossa di Tropea" and "Ramata di Montoro" onion-dried skins, we clearly indicated that this agricultural waste can provide bioactive molecules for multiple applications, from industrial to nutraceutical and cosmetical sectors.

17.
Nat Prod Res ; 35(18): 3095-3099, 2021 Sep.
Artículo en Inglés | MEDLINE | ID: mdl-31698954

RESUMEN

Propolis is an attractive natural ingredient to design health products due to its pharmacological effects. Our chemical investigation of a polar extract of Nigerian propolis (NP) led the isolation and identification of five isoflavonoids (1-4, 6), one diarylpropane (5) and one prenylated flavanone (7) by the combination of chromatographic and spectroscopic techniques. Compounds 1, 4 and 7 were found to be the main markers in NP (8.0, 5.0 and 4.0 mg/g of dry extract, respectively). Moreover, NP and its phenolic constituents exhibited in vitro free radical scavenging activity together with a promising antidiabetic effect against α-amylase and α-glucosidase enzymes. Finally, NP showed also a moderate inhibition of Helicobacter pylori growth. These results suggested that NP could be a good candidate in nutraceuticals and food products.


Asunto(s)
Antioxidantes/farmacología , Inhibidores de Glicósido Hidrolasas/farmacología , Própolis , alfa-Amilasas/antagonistas & inhibidores , Antioxidantes/aislamiento & purificación , Inhibidores de Glicósido Hidrolasas/aislamiento & purificación , Helicobacter pylori/efectos de los fármacos , Nigeria , Própolis/química , Própolis/farmacología , alfa-Glucosidasas
18.
Anal Bioanal Chem ; 397(2): 799-806, 2010 May.
Artículo en Inglés | MEDLINE | ID: mdl-20213171

RESUMEN

Organophosphate esters (OPEs), utilized as flame retarding agents and/or plasticizers, are almost ubiquitous in environmental compartments, and biota and foods could be contaminated by bioaccumulation or during the treatment processes. A multiresidue method is proposed for the determination of 13 OPEs in fish tissues: analytes were simultaneously extracted and purified using the matrix solid phase dispersion technique and then determined by gas chromatography with nitrogen-phosphorus detection. The main parameters affecting extraction yield and selectivity, such as the type of dispersant material, clean-up co-sorbent, rinse and elution solvents, were evaluated to obtain lipid-free extracts and quantitative recoveries for OPEs. Under optimal conditions, 0.5 g of samples was dispersed with 2 g Florisil and 1 g anhydrous sodium sulphate and transferred to a solid phase extraction cartridge containing 1 g alumina. The lipids were removed using 5 mL n-hexane/dichloromethane (1:1) and analytes were recovered with 10 mL n-hexane/acetone (6:4) and directly analysed. The method developed provided recoveries between 70 and 110% for different kinds of fish, and the day-to-day variability was between 1 and 9%. This procedure constitutes the first analytical method for the analysis of OPEs in a food matrix and it is applicable to analyse a large number of samples to evaluate the occurrence and sources of OPEs in biota and foods.


Asunto(s)
Cromatografía de Gases/métodos , Peces , Retardadores de Llama/análisis , Organofosfatos/análisis , Animales , Contaminantes Ambientales/análisis , Reproducibilidad de los Resultados , Extracción en Fase Sólida/métodos
19.
Plants (Basel) ; 9(5)2020 Apr 27.
Artículo en Inglés | MEDLINE | ID: mdl-32349234

RESUMEN

Cultivated cardoon is a multipurpose crop with adaptability to limiting environments. Two genotypes ("Bianco Avorio" and "Spagnolo") were comparatively characterized in response to short and prolonged 100 mM NaCl stress in hydroponics. Salt induced no growth variations between genotypes or symptoms of NaCl toxicity, but boosted ABA accumulation in roots and leaves. Both genotypes had high constitutive phenol content, whose major components were depleted upon 2 days of stress only in "Bianco Avorio". Prolonged stress stimulated accumulation of proline, phenylpropanoids, and related transcripts, and non-enzymatic antioxidant activity. Decreased antioxidant enzymes activities upon short stress did not occur for APX in "Spagnolo", indicating a stronger impairment of enzymatic defenses in "Bianco Avorio". Nonetheless, H2O2 and lipid peroxidation did not increase under short and prolonged stress in both genotypes. Overall, the two genotypes appear to share similar defense mechanisms but, in the short term, "Bianco Avorio" depends mainly on non-enzymatic antioxidant phenylpropanoids for ROS scavenging, while "Spagnolo" maintains a larger arsenal of defenses. Upon prolonged stress, proline could have contributed to protection of metabolic functions in both genotypes. Our results provide cues that can be exploited for cardoon genetic improvement and highlight genotypic differences for breeding salinity tolerant varieties.

20.
Food Chem ; 318: 126496, 2020 Jul 15.
Artículo en Inglés | MEDLINE | ID: mdl-32146309

RESUMEN

Beer is one the most consumed alcoholic beverage in the world and its contamination with mycotoxins is of public health concern. This study reports a fast and automated analytical procedure based on a multi-heart-cutting two-dimensional liquid chromatography tandem mass spectrometry method using electrospray ionization for the determination of seven mycotoxins (aflatoxins B1, B2, G2 and G1, ochratoxin A, fumonisins B1 and B2) in beers. The developed method was based on the heart-cutting 2D- HPLC technique in which only the specific portions of the first dimension, in the retention time of analytes, were transferred into the second dimension for the further separation and successive determination. The method uses two different chromatographic columns; in the first dimension, 50 µL of sample was injected on first column, and mycotoxins elution regions were collected in a loop and transferred into the second column for the separation of analytes. Each column operated in gradient elution mode in order to eliminate interfering compounds and improve separation and peak shape. After the optimization, the method has been validated according to EU regulation and finally applied for the analysis of forty beer samples collected from Italian supermarkets. Among all mycotoxins studied, fumonisins B1 was the most widely distributed in analysed beers (>21%) in the range from 0.6 to 12.3 ng mL-1. The automated methodology developed was able to determine accurately and simultaneously seven mycotoxins in beer. This provided a significant reduction of sample handle and, consequently of analysis time.


Asunto(s)
Cerveza/análisis , Cromatografía Líquida de Alta Presión/métodos , Contaminación de Alimentos/análisis , Micotoxinas/química , Espectrometría de Masas en Tándem/métodos , Aflatoxina B1/análisis , Fumonisinas/análisis , Ocratoxinas/análisis
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