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1.
J Ethnopharmacol ; 302(Pt A): 115889, 2023 Feb 10.
Artigo em Inglês | MEDLINE | ID: mdl-36334817

RESUMO

ETHNOPHARMACOLOGICAL RELEVANCE: Lauraceae family includes Nectandra angustifolia a species widely used in the folk medicine of South America against various maladies. It is commonly used to treat different types of processes like inflammation, pain, and snakebites. Snakes of the Bothrops genus are responsible for about 97% of the ophidic accidents in northeastern Argentina. AIM OF THE STUDY: To evaluate the anti-snake activity of the phytochemicals present in N. angustifolia extracts, identify the compounds, and evaluate their inhibitory effect on phospholipase A2 (PLA2) with in vitro and in silico assays. METHODS: Seasonal variations in the alexiteric potential of aqueous, ethanolic and hexanic extracts were evaluated by inhibition of coagulant, haemolytic, and cytotoxic effects of B. diporus venom. The chemical identity of an enriched fraction obtained by bio-guided fractioning was established by UPLC-MS/MS analysis. Molecular docking studies were carried out to investigate the binding mechanisms of the identified compounds to PLA2 enzyme from snake venom. RESULTS: All the extracts inhibited venom coagulant activity. However, spring ethanolic extract achieved 100% inhibition of haemolytic activity. Bio-guide fractioning led to an enriched fraction (F4) with the highest haemolytic inhibition. Five flavonoids were identified in this fraction; molecular docking and Molecular Dynamics (MD) simulations indicated the binding mechanisms of the identified compounds. The carbohydrates present in some of the compounds had a critical effect on the interaction with PLA2. CONCLUSION: This study shows, for the first time, which compounds are responsible for the anti-snake activity in Nectandra angustifolia based on in vitro and in silico assays. The results obtained in this work support the traditional use of this species as anti-snake in folk medicine.


Assuntos
Bothrops , Venenos de Crotalídeos , Lauraceae , Animais , Flavonoides/farmacologia , Simulação de Acoplamento Molecular , Cromatografia Líquida , Extratos Vegetais/uso terapêutico , Espectrometria de Massas em Tandem , Bothrops/fisiologia , Fosfolipases A2/metabolismo
2.
Nat Prod Res ; 37(15): 2583-2590, 2023.
Artigo em Inglês | MEDLINE | ID: mdl-35285352

RESUMO

Alpine pastures have not yet been extensively studied with regard to the presence of alkaloids in herbaceous plants. In this work the alkaloid profiles were characterised from a selection of 62 herbs collected from alpine pastures in north-eastern Italy. High-performance liquid chromatography coupled to a hybrid quadrupole-orbitrap mass spectrometer was used to evaluate the presence of 41 different alkaloids and quantify them using a targeted approach. Provisionally, 118 alkaloids were identified, including both free and glycosylated forms, making use of a homemade database and a suspect screening approach. rucifoline, gramine, heliotrine, lycopsamine, seneciphylline, and veratramine were quantified with concentrations ranging from 6 to about 100 µg kg-1 in 6 plants. Herbaceous plants belonging to the most well-represented plant families (Poaceae, 9 species; Asteraceae, 7; Lamiaceae, 6) showed distinct and characteristic alkaloid profiles and were correctly reclassified with an average accuracy of 85% (Partial Least Squares - Discriminant Analysis).


Assuntos
Alcaloides , Espectrometria de Massas em Tandem , Espectrometria de Massas em Tandem/métodos , Alcaloides/análise , Extratos Vegetais/química , Plantas , Cromatografia Líquida de Alta Pressão/métodos
3.
Molecules ; 26(12)2021 Jun 08.
Artigo em Inglês | MEDLINE | ID: mdl-34201056

RESUMO

The present investigation aimed to provide novel information on the chemical composition and in vitro bioaccessibility of bioactive compounds from raw citrus pomaces (mandarin varieties Clemenule and Ortanique and orange varieties Navel and Valencia). The effects of the baking process on their bioaccessibility was also assessed. Samples of pomaces and biscuits containing them as an ingredient were digested, mimicking the human enzymatic oral gastrointestinal digestion process, and the composition of the digests were analyzed. UHPLC-MS/MS results of the citrus pomaces flavonoid composition showed nobiletin, hesperidin/neohesperidin, tangeretin, heptamethoxyflavone, tetramethylscutellarein, and naringin/narirutin. The analysis of the digests indicated the bioaccessibility of compounds possessing antioxidant [6.6-11.0 mg GAE/g digest, 65.5-97.1 µmol Trolox Equivalents (TE)/g digest, and 135.5-214.8 µmol TE/g digest for total phenol content (TPC), ABTS, and ORAC-FL methods, respectively; significant reduction (p < 0.05) in Reactive Oxygen Species (ROS) formation under tert-butyl hydroperoxide (1 mM)-induced conditions in IEC-6 and CCD-18Co cells when pre-treated with concentrations 5-25 µg/mL of the digests], anti-inflammatory [significant reduction (p < 0.05) in nitric oxide (NO) production in lipopolysaccharide (LPS)-induced RAW264.7 macrophages], and antidiabetic (IC50 3.97-11.42 mg/mL and 58.04-105.68 mg/mL for α-glucosidase and α-amylase inhibition capacities) properties in the citrus pomaces under study. In addition, orange pomace biscuits with the nutrition claims "no-added sugars" and "source of fiber", as well as those with good sensory quality (6.9-6.7, scale 1-9) and potential health promoting properties, were obtained. In conclusion, the results supported the feasibility of citrus pomace as a natural sustainable source of health-promoting compounds such as flavonoids. Unfractionated orange pomace may be employed as a functional food ingredient for reducing the risk of pathophysiological processes linked to oxidative stress, inflammation, and carbohydrate metabolism, such as diabetes, among others.


Assuntos
Citrus sinensis/química , Citrus/química , Extratos Vegetais/química , Extratos Vegetais/farmacologia , Animais , Anti-Inflamatórios/química , Anti-Inflamatórios/farmacologia , Antioxidantes/química , Linhagem Celular , Cromatografia Líquida de Alta Pressão/métodos , Digestão/fisiologia , Flavonoides/química , Flavonoides/farmacologia , Frutas/química , Trato Gastrointestinal/fisiologia , Humanos , Camundongos , Estresse Oxidativo/efeitos dos fármacos , Células RAW 264.7 , Espectrometria de Massas em Tandem/métodos
4.
ACS Omega ; 6(18): 11925-11934, 2021 May 11.
Artigo em Inglês | MEDLINE | ID: mdl-34056347

RESUMO

Stable isotope ratio analysis has been widely used for traceability and authenticity purposes in relation to various food commodities, but only in a limited number of herb and spice species. This study explored the stable isotope ratios of carbon, nitrogen, sulfur, oxygen, and hydrogen (δ13C, δ15N, δ34S, δ18O, and δ2H) of 119 herbs and spices belonging to 116 plant species and 57 plant families collected from the Italian market for the first time. The characteristic value ranges of δ13C, δ15N, δ34S, δ18O, and δ2H of the herbs and spices went from -31.0 to -11.6, -4.7 to 12.0, -5.0 to 22.0, 14.7 to 46.0, and -158 to -12‰, respectively. The isotopic profiles within and between common botanical families and their similarity/dissimilarity between herbs and spices belonging to the common botanical families are also discussed here. The results of this exploratory work highlight the possibility of characterizing herbs and spices and suggest widening the scope of the survey through more extensive sampling and focusing on specific plant species.

5.
Food Chem ; 267: 204-209, 2018 Nov 30.
Artigo em Inglês | MEDLINE | ID: mdl-29934158

RESUMO

Different approaches to analysing the botanical origin of tannins have been proposed in the last fifteen years, but are generally time consuming and require the use of advanced instrumentation. This study aims to suggest an effective, easy, rapid and cheap method based on the acquisition of FT-IR spectra of 3g/L hydroalcoholic tannin solutions, overcoming possible disadvantages due to sample or particle size inhomogeneity. 114 commercial powder tannins from 7 different botanical sources (oak, chestnut, gall, quebracho, tea, grape skin and grape seed) were collected and the FT-IR spectra were acquired in the region 926-5011cm-1. Partial Least Squares regression, Discriminant Analysis and Artificial Neural Networks were applied to FT-IR spectra to investigate the possibility of differentiating the 7 botanical origins. The best results were obtained using Discriminant Analysis, with 95% correct re-classification, and 97% grouping of grape skin and seed in a single source.


Assuntos
Extratos Vegetais/química , Espectroscopia de Infravermelho com Transformada de Fourier/métodos , Taninos/análise
6.
Drug Test Anal ; 10(3): 423-448, 2018 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-28730714

RESUMO

Herbal infusions are consumed worldwide thanks to their "natural" beneficial effects, also due to the presence of alkaloids, although these compounds can have poisonous effects. A method combining online solid-phase purification with high resolution mass spectrometry was used to define the alkaloid profiles of 117 herbs and 7 commercial blends. Forty-one alkaloids were quantified in reference to analytical standards, while the presence of a further 116 was confirmed based on accurate mass, retention time, and fragmentation profile. The targeted study showed that 52% of herbs and 42% of commercial blends contained at least one alkaloid. Pyrrolizidines were the most commonly present (26% of samples), with concentrations generally ranging from the quantification limit to roughly 100 µg kg-1 . Moreover, a homemade infusion was studied, finding on average 45% and 6% lower extraction for pyrrolizidine and steroidal alkaloids, respectively. Nevertheless, the migration of pyrrolizidines was confirmed. The study confirmed the frequent presence, natural or accidental, of alkaloids in commercial infusion herbs, highlighting the urgent need for routine and accurate controls.


Assuntos
Alcaloides/análise , Extratos Vegetais/química , Plantas Medicinais/química , Espectrometria de Massas em Tandem/métodos , Limite de Detecção , Alcaloides de Pirrolizidina/análise , Controle de Qualidade , Extração em Fase Sólida/métodos
7.
J Ethnopharmacol ; 212: 36-42, 2018 Feb 15.
Artigo em Inglês | MEDLINE | ID: mdl-28943445

RESUMO

ETHNOPHARMACOLOGICAL RELEVANCE: Ophidian accidents are a serious public health problem in Argentina; the Bothrops species is responsible for 97% of these accidents, and in particular, B. diporus is responsible for 80% of them. In the northeast of the country (Corrientes Provinces), Cissampelos pareira L. (Menispermaceae) is commonly used against the venom of B. diporus; its use is described in almost all ethnobotanical literature from countries where the plant grows. AIM OF THE STUDY: In this study, the in vitro and in vivo antivenom activities of C. pareira extracts were evaluated against B. diporus venom, with a particular focus on the local effects associated with envenoming. The seasonal influence on the chemical composition of the active extracts was also studied, in order determine the associated range of variability and its influence on the antivenom activity. MATERIALS AND METHODS: This research was conducted using aerial parts (leaves, flowers, tender stems) and roots of Cissampelos pareira collected from two different phytogeographic regions of Corrientes (Argentina); Paso de la Patria and Lomas de Vallejos. In addition, to perform a seasonal analysis and to evaluate the metabolic stability, material was collected at three different growth stages. In vivo and in vitro anti-snake venom activities were tested, and a bio-guided chromatographic separation was performed in order to determine the active chemicals involved. The fractions obtained were analyzed by sodium dodecyl sulfate polyacrylamide gel electrophoresis (SDS-PAGE) and the chemical profile of the most active constituent was analyzed by ultra high-performance liquid chromatography coupled to quadrupole/high-resolution mass spectrometry (Q-Orbitrap). (UHPLC-MS). RESULTS: The alcoholic extract was found to be the most active The bio-guided fractionation allowed selection one fraction to be analyzed by UHPLC-MS in order to identify the components responsible for the activities found; this identified five possible flavonoids. CONCLUSIONS: Our studies of the activity of C. pareira against the venom of B. diporus have confirmed that this species possesses inhibitory effects in both in vitro and in vivo models. Moreover, the present data demonstrate that certain flavonoids may mitigate some of the venom-induced local tissue damage.


Assuntos
Bothrops/fisiologia , Cissampelos/química , Venenos de Crotalídeos/antagonistas & inibidores , Venenos de Crotalídeos/toxicidade , Extratos Vegetais/farmacologia , Animais , Eletroforese em Gel de Poliacrilamida , Hemólise , Extratos Vegetais/química , Folhas de Planta/química , Raízes de Plantas/química , Proteólise
8.
J Mass Spectrom ; 51(9): 729-41, 2016 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-27502171

RESUMO

The biological activity of alkaloids (ALKs) and the different content of these natural products in herbs and plants have made them an attractive field for chemical studies. A screening method automatically combining online solid-phase purification and concentration of samples with analysis using ultra-high performance liquid chromatography coupled with a hybrid quadrupole orbitrap mass spectrometer was developed and is reported in this paper. The proposed quantification method was validated for 35 ALKs with reference to pure analytical standards. A further 48 ALKs were identified on the basis of their accurate mass and characterised for chromatographic retention time and fragmentation profile, following their confirmation in extracts of herbs already well documented in the literature. More than 250 other untargeted ALKs were also tentatively identified using literature information, such as exact mass and isotopic pattern. The mass spectrometer operated in positive ion mode and mass spectra were acquired, with full MS-data-dependent MS/MS analysis (full MS-dd MS/MS) at a resolution of 140 000. The method was linear up to an ALK concentration of 1000/3000 µg l(-1) , with R(2) always >0.99 and limits of detection ranging between 0.04 and 10 µg l(-1) . Accuracy, expressed as the recovery relative error, had a median value of 7.4%, and precision (relative standard deviation %) was generally lower than 10% throughout the quantitation range. The proposed method was then used to investigate the targeted and untargeted ALK profile of a selection of 18 alpine herbal plants, establishing that pyrrolizidine, pyrrolidine and piperidine ALKs were the most well represented. Copyright © 2016 John Wiley & Sons, Ltd.


Assuntos
Alcaloides/análise , Extratos Vegetais/química , Plantas/química , Extração em Fase Sólida/métodos , Espectrometria de Massas em Tandem/métodos , Limite de Detecção , Modelos Lineares , Reprodutibilidade dos Testes
9.
Food Chem ; 206: 274-83, 2016 Sep 01.
Artigo em Inglês | MEDLINE | ID: mdl-27041326

RESUMO

Commercial tannins from several botanical sources and with different chemical and technological characteristics are used in the food and winemaking industries. Different ways to check their botanical authenticity have been studied in the last few years, through investigation of different analytical parameters. This work proposes a new, effective approach based on the quantification of 6 carbohydrates, 7 polyalcohols, and 55 phenols. 87 tannins from 12 different botanical sources were analysed following a very simple sample preparation procedure. Using Forward Stepwise Discriminant Analysis, 3 statistical models were created based on sugars content, phenols concentration and combination of the two classes of compounds for the 8 most abundant categories (i.e. oak, grape seed, grape skin, gall, chestnut, quebracho, tea and acacia). The last approach provided good results in attributing tannins to the correct botanical origin. Validation, repeated 3 times on subsets of 10% of samples, confirmed the reliability of this model.


Assuntos
Fenóis/análise , Taninos/análise , Acacia/química , Antioxidantes/análise , Carboidratos/análise , Limite de Detecção , Extratos Vegetais/análise , Reprodutibilidade dos Testes , Sementes/química , Chá/química , Vitis/química
10.
J Agric Food Chem ; 58(1): 570-7, 2010 Jan 13.
Artigo em Inglês | MEDLINE | ID: mdl-20000737

RESUMO

H, C, and O stable isotope ratios and the elemental profile of 267 olive oils and 314 surface waters collected from 8 European sites are presented and discussed. The aim of the study was to investigate if olive oils produced in areas with different climatic and geological characteristics could be discriminated on the basis of isotopic and elemental data. The stable isotope ratios of H, C, and O of olive oils and the ratios of H and O of the relevant surface waters correlated to the climatic (mainly temperature) and geographical (mainly latitude and distance from the coast) characteristics of the provenance sites. It was possible to characterize the geological origin of the olive oils by using the content of 14 elements (Mg, K, Ca, V, Mn, Zn, Rb, Sr, Cs, La, Ce, Sm, Eu, U). By combining the 3 isotopic ratios with the 14 elements and applying a multivariate discriminant analysis, a good discrimination between olive oils from 8 European sites was achieved, with 95% of the samples correctly classified into the production site.


Assuntos
Isótopos de Carbono/análise , Deutério/análise , Isótopos de Oxigênio/análise , Óleos de Plantas/química , Elementos Químicos , Europa (Continente) , Marcação por Isótopo , Azeite de Oliva , Controle de Qualidade
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