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1.
Spectrochim Acta A Mol Biomol Spectrosc ; 316: 124384, 2024 Aug 05.
Artículo en Inglés | MEDLINE | ID: mdl-38701576

RESUMEN

The bioactive compounds Acetyl-11-keto-ß-boswellic acid (AKBA) and 11-keto-ß-boswellic acid (KBA), found in the resin of the Boswellia tree, exhibit anti-inflammatory properties, rendering Boswellia resin an intriguing natural medicinal products. However, the content of boswellic acids varies across different Boswellia species and proper knowledge of its species-dependent nature, as well as alternatives to the resource- and time-intensive HPLC analysis, are lacking. Here we present a comprehensive investigation into the boswellic acid content of seven Boswellia species from ten countries and introduce a novel and non-destructive Near-Infrared spectroscopy method for predicting boswellic acid concentrations in solid resin samples. The HPLC-UV reference analysis revealed AKBA concentrations of up to 7.27 % (w/w) with KBA concentrations reaching up to 1.28 % (w/w). Principal Component Analysis of the HPLC and NIR spectroscopy data unveiled species-specific variations, facilitating differentiation based on boswellic acid content, characteristic chromatograms and NIR spectra. Using the HPLC-UV quantification as reference, we developed a Partial Least Squares regression model based on NIR spectra of the resin samples. This model demonstrated highly satisfactory predictive capabilities for AKBA content, achieving a root mean square error of prediction of 0.74 % (w/w) and an R2val of 0.79 in independent test set validation. Although the model was less effective for predicting KBA content, it still offered valuable estimates. The spectroscopic method introduced in this study provides a cost-effective and solvent-free approach for predicting boswellic acid content, demonstrating the potential for application in non-laboratory settings through the use of miniaturized NIR spectrometers. Consequently, this method aligns well with the principles of green chemistry and addresses the growing demand for alternative analytical techniques.


Asunto(s)
Boswellia , Análisis de Componente Principal , Resinas de Plantas , Espectroscopía Infrarroja Corta , Triterpenos , Boswellia/química , Espectroscopía Infrarroja Corta/métodos , Triterpenos/análisis , Cromatografía Líquida de Alta Presión/métodos , Resinas de Plantas/química , Resinas de Plantas/análisis , Análisis Multivariante , Especificidad de la Especie
2.
Spectrochim Acta A Mol Biomol Spectrosc ; 310: 123955, 2024 Apr 05.
Artículo en Inglés | MEDLINE | ID: mdl-38306925

RESUMEN

This comprehensive review paper aims to captivate the applicability of in-sorbent detection, where near-infrared spectroscopy (NIRS) converges with enrichment technologies. For this purpose, we collected and summarized information regarding the combination of several sophisticated analytical enrichment techniques with NIRS to further explore and develop this synergistic approach. Peer-reviewed publications, matching the criteria of in situ NIR measurements prior analyte elution, have been collected, investigated, and concluded within this review. Investigations according to used materials, commercial or self-made, composition, organic or inorganic and applied analytical methodologies have been carried out. Applications extending over a multitude of chemical fields, from environmental to medicinal applications. As this review concludes, the combination of these techniques further expands the applicability of NIRS and moreover tries to solve the long-standing issue of the comparably low sensitivity regarding this vibrational technique.

3.
Front Psychiatry ; 14: 1200643, 2023.
Artículo en Inglés | MEDLINE | ID: mdl-37608993

RESUMEN

Introduction: In a quasi-naturalistic study design, we evaluate the change in psychopathological syndromes and general well-being after the alleviation of social restrictions. The aim of this study was to investigate the specific relationship between social isolation and depressive syndromes. Methods: At two timepoints, the first during maximal social restrictions, the second after social restrictions had widely ended for 9 months, depressive and other syndromes were measured in an online survey addressing the total cohort of students registered at Heidelberg University, Germany via e-mail (n = 27,162). The complete Patient Health Questionnaire (PHQ) was used with nine items for depressive syndromes. In addition, well-being was measured by the Well-Being Index WHO-5. In the quantitative and qualitative part of the study psychopathological syndromes and well-being were related to social isolation and feelings of loneliness. Results: After 1.5 years of pandemic-related social restrictions, "major" depressive syndromes were reported by 40.16% of the respondents to the PHQ in a sample of 2,318 university students. 72.52% showed a severely reduced Well-Being-Index. Nine months after the end of social restrictions, "major" depressive syndromes were reported by 28.50% of the participants. Well-being improved after the alleviation of social restrictions, as well: 53.96% showed a Well-Being Index of below 50 vs. 72.52% in the first study. The quantitative and qualitative analysis of the free texts of the respondents suggest that a significant amount of depressive syndromes and reduced well-being are related to social isolation and loneliness. While in the times of the pandemic restrictions the participants mostly reported "loneliness and social isolation" (24.2%) as their main problem, only 7.7% described these as their main problem after social restrictions had been loosened for 9 months. The qualitative analysis hints that at t2 participants were more likely to mention possible ways to actively deal with loneliness than at t1, which might be interpreted along the lines of the decrease in depressive syndromes. Discussion: Keeping the self-selection bias in mind our study results suggest that one third of "major" depressive syndromes and one quarter of severely reduced well-being accompany social restrictions or are even caused by them, with loneliness being an important factor. These results should be taken into account by health policies when coping with future pandemics.

4.
Anal Methods ; 15(20): 2448-2455, 2023 05 25.
Artículo en Inglés | MEDLINE | ID: mdl-37158281

RESUMEN

E-liquids have become increasingly popular in society in recent years. A wide variety of flavors and nicotine strengths make it possible for every user to get a product according to their wishes. Many of these e-liquids are marketed with countless different flavors, which are often characterized by a strong and sweet smell. Sweeteners, such as sucralose, are therefore commonly added as sugar substitutes. However, recent studies have shown the potential formation of highly toxic chlorinated compounds. This can be explained by the high temperatures (above 120 °C) within the heating coils and the used basic composition of these liquids. Nevertheless, the legal situation is composed of proposals without clear restrictions, only recommendations for tobacco products. For this reason, a high level of interest lies within the establishment of fast, reliable and cost-effective methods for the detection of sucralose in e-liquids. In this study, a number of 100 commercially available e-liquids was screened for sucralose in order to identify the suitability of ambient mass spectrometry and near-infrared spectroscopy for this application. A highly sensitive high-performance liquid chromatography coupled to a tandem mass spectrometer method was used as reference method. Furthermore, the advantages and limitations of the two mentioned methods are highlighted in order to provide a reliable quantification of sucralose. The results clearly revile the necessity for product quality due to the absence of declaration on many of the used products. Further on, it could be shown, that both methods are suitable for the quantification of sucralose in e-liquids, with beneficial economic and ecological aspects, over classical analytical tools including high-performance liquid chromatography. Clear correlations between the reference and novel developed methods are displayed. In summary, these methods enable an important contribution to ensure consumer protection and elimination of confuse package labelling.


Asunto(s)
Sistemas Electrónicos de Liberación de Nicotina , Espectroscopía Infrarroja Corta , Sacarosa/análisis , Edulcorantes/análisis , Espectrometría de Masas
5.
Food Chem ; 403: 134418, 2023 Mar 01.
Artículo en Inglés | MEDLINE | ID: mdl-36358098

RESUMEN

This work is the first to describe the application of Direct Analysis in Real Time Mass Spectrometry for rapid and simple quality control of black truffles. Multivariate analyses (PCA and LDA) of mass spectra provided highly efficient models for the discrimination of four truffle species, namely Tuber melanosporumVittad., Tuber aestivumVittad., Tuber uncinatumChatin and Tuber indicum Cooke etMassee. Full-cross validations showed prediction accuracies up to 99%. Hydrophilic Interaction Liquid Chromatography Mass Spectrometry was used as a reference method and the results of both methods were compared to each other. Multivariate models of the chromatograms also showed excellent results with prediction accuracies of 100%. In a direct comparison of methods, Direct Analysis in Real Time Mass Spectrometry showed minimally lower prediction accuracies, but was significantly faster, more robust and easier to use, making it an excellent choice for rapid quality control of black truffles.


Asunto(s)
Espectrometría de Masas , Cromatografía Liquida , Control de Calidad , Interacciones Hidrofóbicas e Hidrofílicas
6.
Anal Methods ; 14(39): 3875-3880, 2022 10 13.
Artículo en Inglés | MEDLINE | ID: mdl-36156611

RESUMEN

This work is the first to describe the use of Direct Analysis in Real Time Mass Spectrometry (DART-MS) for the rapid quantification of cannabidiol (CBD) in CBD oils. For this study, self-prepared samples spiked with CBD in hemp seed oil as well as commercial CBD oils from the Austrian market with different CBD contents were analyzed. CBD concentrations were between 5 and 30% (m/m) for the spiked samples as well as between 5 and 15% (m/m) for the real samples. The performance of quantification by means of DART-MS was assessed against a validated liquid chromatography-mass spectrometry (LC-MS) method. The correlation of the quantification results of both methods was high with a correlation factor greater than 0.98 and a maximum bias of 9.8%. Furthermore, the relative standard deviation values of the DART-MS measurments were below the tolerable limit of 12%. These results demonstrate that quantification of CBD by DART-MS is reliable and hence suitable as a rapid and cost-effective alternative method for quality control of CBD content in CBD oils.


Asunto(s)
Cannabidiol , Cannabis , Cannabidiol/análisis , Cannabidiol/química , Cannabis/química , Espectrometría de Masas , Extractos Vegetales , Aceites de Plantas
7.
Anal Methods ; 14(27): 2689-2697, 2022 07 14.
Artículo en Inglés | MEDLINE | ID: mdl-35766306

RESUMEN

Pyrrolizidine alkaloids are phytochemicals, which present a highly toxic class of compounds in multiple food resources and are therefore a late-breaking topic in food safety. This study describes the first use of modified halloysite nanotubes as a novel solid material for solid phase extraction. As a result of a fast one-pot sulfonation of the cheap and non-toxic halloysite nanotubes, an efficient cation exchange phase has been prepared. After optimization of the solid phase extraction protocol, high extraction efficiencies and overall recoveries were obtained for a mixture of four pyrrolizidine alkaloid structures through UHPLC-MS/MS analysis with caffeine as the internal standard. Furthermore, the novel solid phase was used for the selective binding of the toxic pyrrolizidine alkaloids in a real-life honey sample, which itself is often contaminated with these compounds. In-house validation showed great extraction efficiencies up to 99.9% for senecionine with a lower limit for lycopsamine with 59.3%, which indicated high selectivity even in the presence of potential interfering compounds. Subsequently, overall recoveries up to 91.5% could be obtained for senecionine while the lowest value was reached for lycopsamine with 55.1%. Comparison with a commercial strong cation exchange tube procedure showed the high competitiveness of the novel solid phase with respect to overall performance. Only slight disadvantages regarding precision and repeatability with values under 5.7% and 11.6% could be observed. Therefore, sulfonated halloysite nanotubes present themselves as an easy to prepare, cheap and highly efficient novel cation exchange material for the selective solid phase extraction of toxic pyrrolizidine alkaloids in frequently contaminated real-life samples like honey.


Asunto(s)
Nanotubos , Alcaloides de Pirrolicidina , Cationes , Cromatografía Líquida de Alta Presión , Arcilla , Nanotubos/análisis , Alcaloides de Pirrolicidina/análisis , Alcaloides de Pirrolicidina/química , Extracción en Fase Sólida/métodos , Espectrometría de Masas en Tándem
8.
Anal Methods ; 14(16): 1603-1610, 2022 04 21.
Artículo en Inglés | MEDLINE | ID: mdl-35383798

RESUMEN

Melatonin is a hormone that regulates the biological day and night cycle. It is mainly produced by the pineal gland during the night. People suffering from insomnia use it as a soporific drug. The aim of this study was to develop a method for the rapid quantification of melatonin in hypnotics. For that purpose, atmospheric pressure solid analysis probe-assisted mass spectrometry was applied, where no chromatographic separation is needed. Thereby, one single analysis takes less than 1 min. Reference measurements were performed with ultra-high-performance liquid chromatography coupled with a quadrupole-time-of-flight mass spectrometer. Both methods were validated and real sample extracts were tested. The coefficients of determination were above 0.97 for both methods. The limits of detection and quantification were below 1 mg kg-1. Both methods gave comparable results. Moreover, the content of melatonin differed from the specified value in many samples. The highest and lowest observed deviations were 78% and 1%, respectively.


Asunto(s)
Melatonina , Espectrometría de Masas en Tándem , Presión Atmosférica , Cromatografía Líquida de Alta Presión/métodos , Humanos , Hipnóticos y Sedantes , Espectrometría de Masas en Tándem/métodos
9.
J Pharm Biomed Anal ; 214: 114720, 2022 May 30.
Artículo en Inglés | MEDLINE | ID: mdl-35286987

RESUMEN

Herbal medicines are commonly used in many countries all around the world. In Western countries they are now gaining more and more popularity, whereas in countries like China and India they have been entrenched for millenniums. Some of these perceived herbal medicines claim to help when suffering from erectile dysfunction. Nevertheless, many of these products are adulterated with PDE5 inhibitors like sildenafil or α-blockers. Patients who suffer from high blood pressure sometimes resort to herbal products, as they are not allowed to take sildenafil because of negative drug-drug interactions with nitrates (often utilized as treatment for coronary diseases). Products which are then adulterated with PDE5 inhibitors, can seriously harm patients. Therefore, this study reports the instant screening of alleged herbal products by employing atmospheric pressure solids analysis probe and high-resolution mass spectrometry to determine adulterants. Three out of 12 investigated products contained sildenafil in ranges from 0.5% to 18%. Multivariate analysis of ambient mass spectrometry measurements revealed encouraging outcomes for distinguishing non-sildenafil and sildenafil adulterated samples. Atmospheric pressure solids analysis probe is therefore a promising method for the rapid determination of sildenafil in herbal products with possible downstream semiquantitative analysis.


Asunto(s)
Contaminación de Medicamentos , Inhibidores de Fosfodiesterasa 5 , Presión Atmosférica , Contaminación de Medicamentos/prevención & control , Humanos , Masculino , Espectrometría de Masas/métodos , Medicamentos sin Prescripción , Inhibidores de Fosfodiesterasa 5/análisis , Citrato de Sildenafil/química
10.
Molecules ; 27(3)2022 Jan 18.
Artículo en Inglés | MEDLINE | ID: mdl-35163862

RESUMEN

Truffles represent the best known and most expensive edible mushroom. Known as Ascomycetes, they belong to the genus Tuber and live in symbiosis with plant host roots. Due to their extraordinary taste and smell, truffles are sold worldwide for high prices of up to 3000-5000 euros per kilogram (Tuber magnatum PICO). Amongst black truffles, the species Tuber melanosporum VITTAD. is highly regarded for its organoleptic properties. Nonetheless, numerous different sorts of black truffle are offered at lower prices, including Tuber aestivum VITTAD., Tuber indicum and Tuber uncinatum, which represent the most frequently consumed types. Because truffles do not differ visually for inexperienced consumers, food fraud is likely to occur. In particular, for the highly prized Tuber melanosporum, which morphologically forms very similar fruiting bodies to those of Tuber indicum, there is a risk of fraud via imported truffles from Asia. In this study, 126 truffle samples belonging to the four mentioned species were investigated by four different NIR instruments, including three miniaturized devices-the Tellspec Enterprise Sensor, the VIAVI solutions MicroNIR 1700 and the Consumer Physics SCiO-working on different technical principles. Three different types of measurement techniques were applied for all instruments (outer shell, rotational device and fruiting body) in order to identify the best results for classification and quality assurance in a non-destructive manner. Results provided differentiation with an accuracy up to 100% for the expensive Tuber melanosporum from Tuber indicum. Classification between Tuber melanosporum, Tuber indicum, Tuber aestivum and Tuber uncinatum could also be achieved with success of 100%. In addition, quality monitoring including discrimination between fresh and frozen/thawed, and prediction of the approximate date of harvesting, was performed. Furthermore, feasibility studies according to the geographical origin of the truffle were attempted. The presented work compares the performance for prediction and quality monitoring of portable vs. benchtop NIR devices and applied measurement techniques in order to be able to present a suitable, accurate, fast, non-destructive and reliable method for consumers.


Asunto(s)
Ascomicetos/química , Ascomicetos/clasificación , Técnicas Biosensibles/métodos , Contaminación de Alimentos/análisis , Espectroscopía Infrarroja Corta/métodos , Ascomicetos/aislamiento & purificación , Especificidad de la Especie
11.
Biomed Chromatogr ; 36(4): e5340, 2022 Apr.
Artículo en Inglés | MEDLINE | ID: mdl-35043434

RESUMEN

In this study, different injection solutions containing opioid and nonopioid compounds used for patient-controlled analgesia in hospice and palliative care were evaluated in terms of analyte stability. Investigated injection solutions contained different combinations of morphine, hydromorphone, metamizole and esketamine. For the practical implementation, samples from infusion pumps were daily drawn over a period of 7 days at 22 and 37°C. Quantitative measurements were performed on a high-performance liquid chromatography system with ultraviolet detection applying a validated analytical method. All compounds apart from morphine showed no evident changes in concentration. However, a significant loss of morphine was observed for injection mixtures containing both morphine and metamizole at 37°C. After 7 days, only 72% of the initially measured morphine concentration was measured in the binary and 77% in the ternary mixture. Furthermore, an additional compound was detected that could represent the morphine-metamizole-adduct, "metamorphine". Based on these results, a significantly reduced morphine concentration must be expected after only 3 days if an injection solution mixture containing both morphine and metamizole is administered to a patient at 37°C. Since the analgesic effects of morphine-metamizole adducts have not yet been thoroughly investigated, further clinical studies are necessary before accurate conclusions can be drawn in this regard.


Asunto(s)
Hospitales para Enfermos Terminales , Hidromorfona , Analgesia Controlada por el Paciente , Analgésicos Opioides , Dipirona , Humanos , Hidromorfona/química , Ketamina , Morfina , Cuidados Paliativos/métodos
12.
Spectrochim Acta A Mol Biomol Spectrosc ; 265: 120347, 2022 Jan 15.
Artículo en Inglés | MEDLINE | ID: mdl-34537630

RESUMEN

This study describes a newly developed method for the fast and straightforward differentiation of two turmeric species using Direct Analysis in Real Time mass spectrometry and miniaturized Near Infrared spectroscopy. Multivariate analyses (PCA and LDA) were performed on the mass spectrometric data, thus creating a powerful model for the discrimination of Curcumalonga and Curcumaxanthorrhiza. Cross-validation of the model revealed correctness-scores of 100% with 20-fold as well as leave-one-out validation techniques. To further estimate the models prediction power, seven retail samples of turmeric powder were analyzed and assorted to a species. Looking for a fast, non-invasive, cost-efficient and laboratory independent method, miniaturized NIR spectrometers offer an alternative for quality control of turmeric species. However, different technologies implemented to compensate for their small size, lead to different applicability of these spectrometers. Therefore, we investigated the three handheld spectrometers microPHAZIR, MicroNIR 2200 and MicroNIR 1700ES for their application in spice analysis in hyphenation to PCA, LDA and ANN methods used for the discriminant analysis. While microPHAZIR proved to be the most valuable device for differentiating C.longa and C.xanthorrhiza, MicroNIR 1700ES offered the worst results. These findings are interpreted on the basis of a quantum chemical simulation of the NIR spectrum of curcumin as the representative constituent. It was found that the information accessible to MicroNIR 1700ES that is relevant to the analyzed constituents is located in the spectral region prone to interferences with the matrix, likely limiting the performance of this spectrometer in this analytical scenario.


Asunto(s)
Curcuma , Curcumina , Análisis Discriminante , Espectrometría de Masas , Espectroscopía Infrarroja Corta
13.
Talanta ; 238(Pt 2): 123057, 2022 Feb 01.
Artículo en Inglés | MEDLINE | ID: mdl-34801913

RESUMEN

This work is the first to describe the use of Direct Analysis in Real Time mass spectrometry (DART-MS) for the rapid and cost-effective quality control of cigars. Multivariate analyses (PCA and LDA) on mass spectra led to highly efficient models for the discrimination of tobacco products. In addition to the geographic origin of the cigars, different pretreatments of the tobacco leaves could also be determined. Cross-validations of the models yielded prediction accuracies up to 92.18%. All results were compared using LC-MS as reference method. Multivariate analyses of chromatograms also yielded powerful models with correctness scores up to 88.1%. However, the models generated with LC-MS were neither able to determine the geographic origin of the tobacco leaves nor different pretreatments. In addition to qualitative analysis, the nicotine content of tobacco leaves was also determined via both methods. While precise quantification was not possible with DART-MS, a correlation coefficient of >0.96 was achieved in direct comparison with LC-MS, which allows semi-quantitative statements about the nicotine content without any problems.


Asunto(s)
Productos de Tabaco , Cromatografía Liquida , Espectrometría de Masas , Control de Calidad
14.
Chem Res Toxicol ; 34(12): 2522-2533, 2021 12 20.
Artículo en Inglés | MEDLINE | ID: mdl-34879203

RESUMEN

Capsaicin, primarily known as the pungent ingredient in hot peppers, is rapidly metabolized in the human body by enzymatic processes altering the pharmacological as well as toxicological properties. Herein, the oxidative transformation of capsaicin was investigated in vitro with electrochemistry as well as human liver microsomal incubations. The reaction mixtures were analyzed with liquid chromatography-mass spectrometry. Structure elucidation involved accurate mass measurements and multistage tandem mass spectrometry experiments. In total, 126 transformation products were detected. Electrochemistry provided evidence for 101 transformation products and the microsomal incubations for 46 species. 21 compounds were observed with both approaches. Identified oxidative pathways likely occurring during the phase I metabolism included dehydrogenation, O-demethylation, and hydroxylation reactions as well as combinations thereof. Furthermore, trapping of reactive intermediates either with glutathione or with electrochemically activated ribonucleosides provided evidence for the possible production of phase II metabolites and covalent adducts with a genetic material. Evidence for the occurrence of some capsaicin metabolites in humans was obtained by urine screening.


Asunto(s)
Capsaicina/metabolismo , Técnicas Electroquímicas , Capsaicina/orina , Cromatografía Liquida , Voluntarios Sanos , Humanos , Espectrometría de Masas , Microsomas Hepáticos/química , Microsomas Hepáticos/metabolismo , Oxidación-Reducción
15.
Toxicol Appl Pharmacol ; 430: 115727, 2021 11 01.
Artículo en Inglés | MEDLINE | ID: mdl-34543670

RESUMEN

Electronic cigarettes (e-cigarettes) have gained increasing popularity in recent years, mostly because they are supposed to be less harmful than regular cigarettes. Therefore, it is highly imperative to investigate possible noxious effects to protect the consumers. E-liquids consist of propylene glycol, glycerol, aroma compounds and sweeteners. One of these sweeteners is a chlorinated version of sucrose, namely sucralose. The aim of this work was to investigate degradation products of sucralose in the presence of propylene glycol and glycerol at different temperatures of commercially available e-cigarettes. Chemical analysis and biological tests were simultaneously performed on e-liquid aerosol condensates. The results of the chemical analysis, which was executed by employing GC-MS/GC-FID, demonstrated high amounts of various chloropropanols. The most abundant one is extremely toxic, namely 3-chloropropane-1,2-diol, which can be detected at concentrations ranging up to 10,000 mg/kg. Furthermore, a cytotoxicity investigation of the condensates was performed on HUVEC/Tert2 cells in which metabolic activity was determined by means of resazurin assay. The cellular metabolic activity significantly decreased by treatment with e-liquid aerosol condensate. Due to the results of this study, we advise against the use of sucralose as sweetener in e-liquids.


Asunto(s)
Sistemas Electrónicos de Liberación de Nicotina , Glicerol/toxicidad , Propilenglicol/toxicidad , Sacarosa/análogos & derivados , Edulcorantes/toxicidad , Vapeo/efectos adversos , alfa-Clorhidrina/toxicidad , Células Cultivadas , Seguridad de Productos para el Consumidor , Estabilidad de Medicamentos , Glicerol/química , Células Endoteliales de la Vena Umbilical Humana/efectos de los fármacos , Células Endoteliales de la Vena Umbilical Humana/metabolismo , Células Endoteliales de la Vena Umbilical Humana/patología , Humanos , Propilenglicol/química , Medición de Riesgo , Sacarosa/química , Sacarosa/toxicidad , Edulcorantes/química , Temperatura , Pruebas de Toxicidad , Volatilización , alfa-Clorhidrina/química
16.
Molecules ; 26(16)2021 Aug 09.
Artículo en Inglés | MEDLINE | ID: mdl-34443395

RESUMEN

Recently polyphenols attracted great interest in the field of food and nutrition as well as in the pharmaceutical and cosmetics industries due to their health benefits through antioxidative behavior in the human body. However, because of the high number of compounds characterized as phenols and their structural diversity, quantification of polyphenols turns out to be a highly complex task. Although, a wide variety of analytical methods are used for the determination of total polyphenolic content, they are all found to be lacking in a variety of different tasks, such as their limits of detection and quantification, repeatability, accuracy and specificity. For this reason, a novel approach combining the advantages of solid phase purification, near infrared analysis and multivariate data analysis was investigated for the prediction of total polyphenolic content, suitable for a wide range of sample matrices. Dispersive solid phase extraction was performed and optimized using polyvinylpyrrolidone as sorbent, known to selectively bind polyphenols. Near-infrared detection of adsorbed polyphenols was carried out subsequently. Furthermore, the method was in-house validated, examining selectivity, repeatability and accuracy, working range, as well as multivariate limit of detection and limit of quantification, comparing it with two routinely used methods-namely, Folin-Ciocalteu photometric assay and Löwenthal titration. The novel established method was applied for the prediction of total polyphenolic content in tea and wine samples.


Asunto(s)
Polifenoles/aislamiento & purificación , Povidona/química , Extracción en Fase Sólida , Antioxidantes/química , Humanos , Polifenoles/química
17.
Sensors (Basel) ; 20(17)2020 Sep 02.
Artículo en Inglés | MEDLINE | ID: mdl-32887485

RESUMEN

Elderberry (Sambucus nigra L., fructus) is a very potent herbal drug, deriving from traditional European medicine (TEM). Ripe elderberries are rich in anthocyanins, flavonols, flavonol esters, flavonol glycosides, lectins, essential oils, unsaturated fatty acids and vitamins. Nevertheless, unripe elderflower fruits contain a certain amount of sambunigrin, a toxic cyanogenic glycoside, whose concentration decreases in the ripening process. Therefore, quality assurance must be carried out. The standard method described in literature is the photometric determination (pH-differential method) of the total anthocyanin content (TAC) that is the highest when the berries are ripe. The drawback of the pH-differential method is the extensive sample preparation and the low accuracy of the method. Therefore, the goal of this publication was to develop a fast non invasive near-infrared (NIR) method for the determination of TAC in whole berries. TAC of elderberries was measured using pH-differentiation method where TAC values of 632.87 mg/kg to 4342.01 mg/kg were measured. Additionally, cyanidin-3-O-glucoside, cyanidin-3-O-sambubioside and cyanidin-3-O-sambubioside-5-O-glucoside which represent more than 98% of TAC in elderberry were quantified using ultra high performance liquid chromatography-multiple wavelength detection-ultra high resolution-quadrupole-time of flight-mass spectrometry (UHPLC-MWD-UHR-Q-TOF-MS) and their sum parameter was determined, ranging between 499.43 mg/kg and 8199.07 mg/kg. Using those two methods as reference, whole elderberries were investigated by NIR spectroscopy with the Büchi NIRFlex N-500 benchtop spectrometer. According to the constructed partial least squares regression (PLSR) models the performance was as follows: a relative standard deviation (RSDPLSR) of 13.5% and root mean square error of calibration (RMSECV/RMSEC) of 1.31 for pH-differentiation reference and a RSDPLSR of 12.9% and RMSECV/RMSEC of 1.28 for the HPLC reference method. In this study, we confirm that it is possible to perform a NIR screening for TAC in whole elderberries. Using quantum chemical calculations, we obtained detailed NIR band assignments of the analyzed compounds and interpreted the wavenumber regions established in PLSR models as meaningful for anthocyanin content. The NIR measurement turned out to be a fast and cost-efficient alternative for the determination of TAC compared to pH-differential method and UHPLC-MWD-UHR-Q-TOF-MS. Due to the benefit of no sample preparation and extraction the technology can be considered as sustainable green technology. With the above mentioned inversely proportional ratio of TAC to total amount of toxic cyanogenic glycosides, NIR proves to be a reliable screening method for the ideal harvest time with maximal content of TAC and lowest content of cyanogenic glycosides in elderberry.


Asunto(s)
Sambucus , Antocianinas/análisis , Cromatografía Líquida de Alta Presión , Frutas/química , Espectroscopía Infrarroja Corta
18.
Int Rev Psychiatry ; 32(7-8): 616-624, 2020.
Artículo en Inglés | MEDLINE | ID: mdl-32885690

RESUMEN

Creativity is the ability to produce something novel and useful that is a valuable contribution to a specific domain. It is a significant common factor in most forms of psychotherapy. Accordingly, it is essential to investigate its role both in psychotherapy in general and in specific approaches like relational, cognitive-behavioural, psychodynamic, systemic, and existential psychotherapy. Positive psychology in particular has pointed up the usefulness of creativity in psychotherapy. Here we draw upon a case example to show how the creative discovery of novel and useful solutions takes place in different dimensions: relational, behavioural, psychodynamic, systemic and existential. The case description demonstrates how principles of positive psychology are useful in many realms of psychotherapy. We propose an integrated model of psychotherapy that brings together different psychotherapeutic methods and is based on interdisciplinary creativity research. The integration of neuroscientific, psychological and cultural findings produced by creativity research can be expected to lead to a deeper understanding of psychotherapeutic, positive-psychological, and creative processes.


Asunto(s)
Creatividad , Psicología Positiva , Psicoterapia , Adolescente , Femenino , Humanos
19.
Anal Methods ; 12(35): 4377-4386, 2020 09 17.
Artículo en Inglés | MEDLINE | ID: mdl-32852487

RESUMEN

This study reports the synthesis of the room temperature ionic liquid 1-propyloxy-3-ethoxyimidazolium bis(trifluoromethane)sulfonamide for the extraction of bergapten and bergamottin from hydroalcoholic cosmetic samples by means of dispersive liquid-liquid microextraction. Molecular structures of the final ionic liquid as well as intermediate products were confirmed by nuclear magnetic resonance spectroscopy. Analyses were performed with high performance liquid chromatography with subsequent diode array and fluorescence detection. The extraction procedure was optimized with the design of the experiment using a three level Box-Behnken approach. Applying the synthesized room temperature ionic liquid as extraction medium, the optimized workflow demonstrated high recoveries illustrating powerful isolation properties for furanocoumarins, which are comparable or even better than using typical extraction solvents. Moreover, the workflow was validated regarding instrumental limits, linearity, accuracy, repeatability and stability of analytes according to international guidelines. To test its applicability on a more complex matrix, hydroalcoholic cosmetic samples were analyzed. Despite highly complex matrices, accurate and precise quantification in the range of 0.04-1.25 µg mL-1 was achieved in spiked and unspiked samples, with bias <10% and RSD < 12%.

20.
Anal Chim Acta ; 1101: 211-221, 2020 Mar 08.
Artículo en Inglés | MEDLINE | ID: mdl-32029113

RESUMEN

Furanocoumarins are a class of naturally occurring phototoxic substances widely spread throughout the Umbelliferae and Rutacea families of plants. Plant extract of these families (e.g. citrus extracts) are commonly used as ingredients in fragrances and cosmetic products. Due to their phototoxicity these substances are regulated within the European Union according to the European Regulation (EC) No. 1223/2009 on cosmetic products. The proposed analytical workflow aims to swiftly screen out and determine the amount of phototoxic furanocoumarins in natural cosmetics employing solid-phase extraction (SPE). Cosmetic samples were first extracted in methanol and subsequently diluted in 35% (v/v) methanol before being applied to solid-phase extraction. The extraction procedure allows extraction of the eight target compounds including the six marker-substances proposed by the International Fragrance Association (IFRA) from complex cosmetic samples with satisfactory recovery levels ranging from 84 to 116% with the exception of bergamottin (68-89%). HPLC-UV and ESI-MS were used for the analysis of the target compounds. Furanocoumarin quantification was performed by standard addition. The workflow was successfully validated according to the ISO 12787 international standard ("Cosmetics - Analytical methods- Validation criteria for analytical results using chromatographic techniques"). Results of the validation on standard solutions highlight a LOQ of 0.01 mg kg-1, acceptable linearity up to 1 mg/kg as well as good accuracy (Bias <15%) and precision (RSD <15%). Total furanocoumarin levels of the examined natural cosmetic products were in general in agreement with the European Regulation. However, it was shown that total levels of furanocoumarins might be significantly higher than assumed using the six proposed marker substances only.


Asunto(s)
Cromatografía Liquida/métodos , Cosméticos/análisis , Furocumarinas/análisis , Espectrometría de Masas/métodos , Extracción en Fase Sólida/métodos , Luz , Límite de Detección
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