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1.
J Sci Food Agric ; 102(15): 7030-7038, 2022 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-35689485

RESUMO

BACKGROUND: Caragana ambigua has been the part of the dietary routines of the regional people in south-west Pakistan and has traditionally been used for the treatment of diabetes there. There is an increased production of reactive oxygen species in diabetics, leading to gastrointestinal disorders. Natural antioxidants exhibit gastroprotective effects owing to their free-radical scavenging action. C. ambigua possesses appreciable phenolic and flavonoid content; thus, it has the potential to protect against gastrointestinal disorders (e.g. gastric ulcer). RESULTS: This study reports the anti-ulcer potential of C. ambigua. Four different fractions (chloroform, ethyl acetate, butanol, and aqueous) of plant were compared against omeprazole. Ulcer index, ulcer inhibition percentage, gastric pH and volume, total acidity, gastric protein, gastric wall mucus, and histopathology of gastric walls of rats were assessed. All fractions exhibited a reduction in ulcer index and promotion of percentage of ulcer inhibition compared with the ulcer control group. Furthermore, the fractions revealed a significant (P < 0.001) diminution in gastric volume and total acidity with an increase in pH. Among the fractions investigated, the chloroform fraction unveiled the most promising anti-ulcer activity, which is comparable to omeprazole. Liquid chromatography-tandem mass spectrometry screening of fractions revealed the presence of formononetin and biochanin A (isoflavones reported to have anti-ulcer properties) in the chloroform fraction. CONCLUSION: This study establishes that C. ambigua possesses significant potential in reducing gastric ulcer progression. Formononetin and biochanin A are chiefly responsible for the stated bioactivity due to the fact that these compounds were solely present in the chloroform fraction. © 2022 The Authors. Journal of The Science of Food and Agriculture published by John Wiley & Sons Ltd on behalf of Society of Chemical Industry.


Assuntos
Antiulcerosos , Caragana , Úlcera Gástrica , Ratos , Animais , Úlcera Gástrica/induzido quimicamente , Etanol/metabolismo , Antiulcerosos/farmacologia , Clorofórmio/efeitos adversos , Clorofórmio/metabolismo , Cromatografia Líquida , Espectrometria de Massas em Tandem , Extratos Vegetais/química , Mucosa Gástrica/metabolismo , Genisteína/metabolismo , Antioxidantes/química , Omeprazol/efeitos adversos
2.
Cells ; 11(9)2022 04 21.
Artigo em Inglês | MEDLINE | ID: mdl-35563717

RESUMO

Inflammatory skin diseases, including atopic dermatitis (AD) and psoriasis, are increasing in populations worldwide. The treatment of patients with AD and other forms of skin inflammation is mainly based on the use of topical corticosteroids or calcineurin inhibitors, which can cause significant side effects with long-term use. Therefore, there is a great need for the development of more effective and less toxic anti-inflammatory agents suitable for the treatment of chronic skin lesions. Here, we screened a number of strains from the ASIB 505 terrestrial algae collection and identified a green algae Chromochloris zofingiensis with pronounced anti-inflammatory properties. We found that a crude nonpolar extract of C. zofingiensis (ID name NAE_2022C), grown upon nitrogen deprivation, acts as a bioactive substance by inhibiting TNFR/NF-κB responses in human skin keratinocyte HaCaT cells. We also found that NAE_2022C suppressed the secretion of pro-inflammatory cytokine tumor necrosis factor α (TNFα) and several Th1- and Th2-related chemokines in a reconstituted human epidermis. The TNFR/NF-κB pathway analysis showed multiple inhibitory effects at different levels and disclosed a direct targeting of IKKß by the extract. Bioassay-guided fractionation followed by high-resolution mass spectrometry detected diacylglyceryl-trimethylhomoserine (DGTS), Lyso-DGTS (LDGTS), 5-phenylvaleric acid, theophylline and oleamide as leading metabolites in the active fraction of NAE_2022C. Further analysis identified betaine lipid DGTS (32:0) as one of the active compounds responsible for the NAE_2022C-mediated NF-κB suppression. Overall, this study presents an approach for the isolation, screening, and identification of anti-inflammatory secondary metabolites produced by soil algae.


Assuntos
Dermatite Atópica , NF-kappa B , Anti-Inflamatórios/uso terapêutico , Dermatite Atópica/patologia , Humanos , NF-kappa B/metabolismo , Extratos Vegetais/química , Extratos Vegetais/farmacologia , Solo
3.
Spectrochim Acta A Mol Biomol Spectrosc ; 265: 120347, 2022 Jan 15.
Artigo em Inglês | MEDLINE | ID: mdl-34537630

RESUMO

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.


Assuntos
Curcuma , Curcumina , Análise Discriminante , Espectrometria de Massas , Espectroscopia de Luz Próxima ao Infravermelho
4.
Planta Med ; 88(1): 20-32, 2022 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-33434938

RESUMO

The content of the flavonolignan mixture silymarin and its individual components (silichristin, silidianin, silibinin A, silibinin B, isosilibinin A, and isosilibinin B) in whole and milled milk thistle seeds (Silybi mariani fructus) was analyzed with near-infrared spectroscopy. The analytical performance of one benchtop and two handheld near-infrared spectrometers was compared. Reference analysis was performed with HPLC following a Soxhlet extraction (European Pharmacopoeia) and a more resource-efficient ultrasonic extraction. The reliability of near-infrared spectral analysis determined through partial least squares regression models constructed independently for the spectral datasets obtained by the three spectrometers was as follows. The benchtop device NIRFlex N-500 performed the best both for milled and whole seeds with a root mean square error of CV between 0.01 and 0.17%. The handheld spectrometer MicroNIR 2200 as well as the microPHAZIR provided a similar performance (root mean square error of CV between 0.01 and 0.18% and between 0.01 and 0.23%, respectively). We carried out quantum chemical simulation of near-infrared spectra of silichristin, silidianin, silibinin, and isosilibinin for interpretation of the results of spectral analysis. This provided understanding of the absorption regions meaningful for the calibration. Further, it helped to better separate how the chemical and physical properties of the samples affect the analysis. While the study demonstrated that milling of samples slightly improves the performance, it was deemed to be critical only for the analysis carried out with the microPHAZIR. This study evidenced that rapid and nondestructive quantification of silymarin and individual flavonolignans is possible with miniaturized near-infrared spectroscopy in whole milk thistle seeds.


Assuntos
Sementes , Silimarina , Análise dos Mínimos Quadrados , Silybum marianum , Extratos Vegetais , Reprodutibilidade dos Testes
5.
Sensors (Basel) ; 20(17)2020 Sep 02.
Artigo em Inglês | MEDLINE | ID: mdl-32887485

RESUMO

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.


Assuntos
Sambucus , Antocianinas/análise , Cromatografia Líquida de Alta Pressão , Frutas/química , Espectroscopia de Luz Próxima ao Infravermelho
6.
Talanta ; 209: 120488, 2020 Mar 01.
Artigo em Inglês | MEDLINE | ID: mdl-31892098

RESUMO

This study investigated the performance of a handheld Raman spectrometer in quantifying melamine in infant formula. Furthermore, the spectrometer's standard stationary sample holder was compared to a custom-built sample rotation unit. The Raman spectra were divided into a calibration set, which was used to construct the partial least squares regression (PLS-R) models, and a test set, which served the purpose of evaluating the model performance with independent samples. It was found that it was possible to reduce the prediction error of melamine in infant formula by up to about 70% using the simple in-house constructed rotation setup. Compared to the rotation setup, even an increased number of point measurements using the spectrometer's standard sample holder was not able to compensate for the lack of representative sample presentation of the inhomogeneous solid mixture to the Raman spectrometer. Moreover, it was found that the custom-built rotation unit enabled faster sample measurements by an adaption of spectrometer parameters. At the same time, the prediction error of the test set samples was kept far lower than with the stationary setup.


Assuntos
Fórmulas Infantis/análise , Software , Triazinas/análise , Animais , Contaminação de Alimentos/análise , Humanos , Lactente , Análise dos Mínimos Quadrados , Leite/química , Análise Multivariada , Análise Espectral Raman
7.
J Hazard Mater ; 355: 180-186, 2018 08 05.
Artigo em Inglês | MEDLINE | ID: mdl-29800912

RESUMO

This study reports the syntheses of four polymeric sorbents based on nucleophilic substitution of Poly(4-vinylbenzylchloride/ethylene glycol dimethacrylate). Polymerization was executed by a simple thermal initiated bulk polymerization procedure. Ground polymer particles were functionalized through reaction with the nucleophiles triethylamine, imidazole, piperidine and pyrrolidine. Mixed-mode phases were characterized by infrared spectroscopy, nitrogen sorption porosimetry and potentiometric titration for determination of chloride content. Furthermore, materials were tested and evaluated for enrichment of seven pharmaceutical and endocrine-disrupting compounds at low ng mL-1 levels. Results demonstrate that the imidazole modified sorbent led to high and constant recovery rates for nearly all tested compounds. Therefore, this polymer was further tested for applicability with two environmental samples. Spiked tap and river water showed similar results as in evaluation experiments. Moreover, the developed method was validated regarding linearity, repeatability, instrumental limits and stability of analytes according to international guidelines.


Assuntos
Metacrilatos/química , Polietilenoglicóis/química , Polivinil/química , Poluentes Químicos da Água/química , Purificação da Água/métodos , Adsorção , Antipirina/química , Carbamazepina/química , Estradiol/química , Estriol/química , Estrogênios/química , Estrona/química , Ibuprofeno/química , Naproxeno/química , Polimerização
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