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1.
Anal Chim Acta ; 1278: 341716, 2023 Oct 16.
Artículo en Inglés | MEDLINE | ID: mdl-37709459

RESUMEN

Cannabis sativa has long been harvested for industrial applications related to its fibers. Industrial hemp cultivars, a botanical class of Cannabis sativa with a low expression of intoxicating Δ9-tetrahydrocannabinol (Δ9-THC) have been selected for these purposes and scarcely investigated in terms of their content in bioactive compounds. Following the global relaxation in the market of industrial hemp-derived products, research in industrial hemp for pharmaceutical and nutraceutical purposes has surged. In this context, metabolomics-based approaches have proven to fulfill the aim of obtaining comprehensive information on the phytocompound profile of cannabis samples, going beyond the targeted evaluation of the major phytocannabinoids. In the present paper, an HRMS-based metabolomics study was addressed to seven distinct industrial hemp cultivars grown in four experimental fields in Northern, Southern, and Insular Italy. Since the role of minor phytocannabinoids as well as other phytocompounds was found to be critical in discriminating cannabis chemovars and in determining its biological activities, a comprehensive characterization of phytocannabinoids, flavonoids, and phenolic acids was carried out by LC-HRMS and a dedicated data processing workflow following the guidelines of the metabolomics Quality Assurance and Quality Control Consortium. A total of 54 phytocannabinoids, 134 flavonoids, and 77 phenolic acids were annotated, and their role in distinguishing hemp samples based on the geographical field location and cultivar was evaluated by ANOVA-simultaneous component analysis. Finally, a low-level fused model demonstrated the key role of untargeted cannabinomics extended to lesser-studied phytocompound classes for the discrimination of hemp samples.


Asunto(s)
Cannabis , Industrias , Suplementos Dietéticos , Flavonoides
2.
J Chromatogr A ; 1703: 464094, 2023 Aug 16.
Artículo en Inglés | MEDLINE | ID: mdl-37262932

RESUMEN

Mitragyna speciosa or kratom is emerging worldwide as a "legal" herbal drug of abuse. An increasing number of papers is appearing in the scientific literature regarding its pharmacological profile and the analysis of its chemical constituents, mainly represented by alkaloids. However, its detection and identification are not straightforward as the plant material is not particularly distinctive. Hyphenated techniques are generally preferred for the identification and quantification of these compounds, especially the main purported psychoactive substances, mitragynine (MG) and 7-hydroxymitragynine (7-OH-MG), in raw and commercial products. Considering the vast popularity of this recreational drug and the growing concern about its safety, the analysis of alkaloids in biological specimens is also of great importance for forensic and toxicological laboratories. The review addresses the analytical aspects of kratom spanning the extraction techniques used to isolate the alkaloids, the qualitative and quantitative analytical methods and the strategies for the distinction of the naturally occurring isomers.


Asunto(s)
Drogas Ilícitas , Mitragyna , Extractos Vegetales/química , Mitragyna/química
3.
Anal Chem ; 94(38): 13117-13125, 2022 09 27.
Artículo en Inglés | MEDLINE | ID: mdl-36121000

RESUMEN

The evaluation of double bond positions in fatty acyl chains has always been of great concern given their significance in the chemical and biochemical role of lipids. Despite being the foremost technique for lipidomics, it is difficult in practice to obtain identification beyond the fatty acyl level by the sole high-resolution mass spectrometry. Paternò-Büchi reactions of fatty acids (FAs) with ketones have been successfully proposed for pinpointing double bonds in FAs in combination with the collision-induced fragmentation technique. In the present paper, an aza-Paternò-Büchi (aPB) reaction of lipids with 6-azauracil (6-AU) was proposed for the first time for the determination of carbon-carbon double bonds in fatty acyl chains using higher collisional dissociation in the negative ion mode. The method was optimized using free FA and phospholipid analytical standards and compared to the standard Paternò-Büchi reaction with acetone. The introduction of the 6-AU moiety allowed enhancing the ionization efficiency of the FA precursor and diagnostic product ions, thanks to the presence of ionizable sites on the derivatizing agent. Moreover, the aPB derivatization allowed the obtention of deprotonated ions of phosphatidylcholines, thanks to an intramolecular methyl transfer from the phosphocholine polar heads during ionization. The workflow was finally applied for pinpointing carbon-carbon double bonds in 77 polar lipids from an yeast (Saccharomyces cerevisiae) extract.


Asunto(s)
Acetona , Carbono , Acetona/química , Carbono/química , Ácidos Grasos , Iones , Fosfatidilcolinas , Fosfolípidos/química , Fosforilcolina , Extractos Vegetales
4.
Phytochem Anal ; 33(4): 507-516, 2022 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-35064611

RESUMEN

INTRODUCTION: Blueberries are known for their very high content of biologically active phenolic compounds; nonetheless, differently from the North American and European species of blueberries, Neotropical blueberries have not been extensively studied yet. OBJECTIVES: In the present paper, the phenolic composition of Vaccinium floribundum Kunth, which is endemic to the Andean regions and grows 1,600 to 4,500 meters above sea level, was investigated by ultra-high-performance liquid chromatography coupled to high-resolution mass spectrometry (UHPLC-HRMS). Native and fermented berries were compared in terms of phenolic composition as well as antioxidant activity, total phenolic content, and total anthocyanin content. MATERIALS AND METHODS: V. floribundum native and fermented berries were extracted and analyzed by UHPLC-HRMS. The acquired datasets were processed by Compound Discoverer 3.1 using a dedicated data analysis workflow that was specifically set up for phenolic compound identification. RESULTS: In total, 309 compounds were tentatively identified, including anthocyanins, flavonoids, phenolic acids, and proanthocyanidins. The molecular transformations of phenolic compounds during fermentation were comprehensively investigated for the first time, and by a customized data processing workflow, 13 quinones and quinone methides were tentatively identified in the fermented samples. Compared to other species of the genus Vaccinium, a peculiar phenolic profile is observed, with low abundance of highly methylated compounds. CONCLUSION: Andean berries are a rich source of a wide variety of phenolic compounds. Untargeted MS analyses coupled to a dedicated data processing workflow allowed expanding the current knowledge on these berries, improving our understanding of the fate of phenolic compounds after fermentation.


Asunto(s)
Vaccinium , Antocianinas/análisis , Antioxidantes/análisis , Cromatografía Líquida de Alta Presión , Biología Computacional , Frutas/química , Espectrometría de Masas , Fenoles/análisis , Extractos Vegetales/química , Vaccinium/química
5.
Molecules ; 26(21)2021 Nov 08.
Artículo en Inglés | MEDLINE | ID: mdl-34771162

RESUMEN

This work describes an untargeted analytical approach for the screening, identification, and characterization of the trans-epithelial transport of green tea (Camellia sinensis) catechin extracts with in vitro inhibitory effect against the SARS-CoV-2 papain-like protease (PLpro) activity. After specific catechin extraction, a chromatographic separation obtained six fractions were carried out. The fractions were assessed in vitro against the PLpro target. Fraction 5 showed the highest inhibitory activity against the SARS-CoV-2 PLpro (IC50 of 0.125 µg mL-1). The untargeted characterization revealed that (-)-epicatechin-3-gallate (ECG) was the most abundant compound in the fraction and the primary molecule absorbed by differentiated Caco-2 cells. Results indicated that fraction 5 was approximately 10 times more active than ECG (IC50 value equal to 11.62 ± 0.47 µg mL-1) to inhibit the PLpro target. Overall, our findings highlight the synergistic effects of the various components of the crude extract compared to isolated ECG.


Asunto(s)
Catequina/farmacología , Proteasas Similares a la Papaína de Coronavirus/metabolismo , Té/metabolismo , Antivirales/química , COVID-19/metabolismo , Células CACO-2 , Camellia sinensis/metabolismo , Catequina/análogos & derivados , Catequina/química , Catequina/metabolismo , Proteasas Similares a la Papaína de Coronavirus/efectos de los fármacos , Epitelio/efectos de los fármacos , Epitelio/metabolismo , Humanos , Espectrometría de Masas/métodos , Extractos Vegetales/química , Extractos Vegetales/farmacología , SARS-CoV-2/efectos de los fármacos , SARS-CoV-2/metabolismo , SARS-CoV-2/patogenicidad , Té/química , Té/fisiología , Tratamiento Farmacológico de COVID-19
6.
Molecules ; 25(12)2020 Jun 12.
Artículo en Inglés | MEDLINE | ID: mdl-32545546

RESUMEN

Chestnut seeds are used for fresh consumption and for the industrial preparation of derivatives, such as chestnut flour. During industrial processing, large amounts of by-products are generally produced, such as leaves, flowers, shells and burs. In the present study, chestnut shells were extracted by boiling water in order to obtain polyphenol-rich extracts. Moreover, for the removal or non-phenolic compounds, a separation by preparative reverse phase chromatography in ten fractions was carried out. The richest fractions in terms of phenolic content were characterized by means of untargeted high-resolution mass spectrometric analysis together with a dedicated and customized data processing workflow. A total of 243 flavonoids, phenolic acids, proanthocyanidins and ellagitannins were tentatively identified in the five richest fractions. Due its high phenolic content (450.03 µg GAE per mg of fraction), one tumor cell line (DU 145) and one normal prostate epithelial cell line (PNT2) were exposed to increasing concentration of fraction 3 dry extract for 24, 48 and 72 h. Moreover, for DU 145 cell lines, increase of apoptotic cells and perturbation of cell cycle was demonstrated for the same extract. Those outcomes suggest that chestnut industrial by-products could be potentially employed as a source of bioresources.


Asunto(s)
Fagaceae/química , Nueces/química , Extractos Vegetales/farmacología , Antioxidantes/química , Línea Celular Tumoral , Proliferación Celular/efectos de los fármacos , Flavonoides/química , Humanos , Masculino , Espectrometría de Masas , Fenoles/química , Extractos Vegetales/química , Polifenoles/química , Próstata/efectos de los fármacos , Neoplasias de la Próstata/tratamiento farmacológico , Semillas/química
7.
Anal Bioanal Chem ; 412(17): 4009-4022, 2020 Jul.
Artículo en Inglés | MEDLINE | ID: mdl-32285185

RESUMEN

The chemical analysis of cannabis potency involves the qualitative and quantitative determination of the main phytocannabinoids: Δ9-tetrahydrocannabinol (Δ9-THC), cannabidiol (CBD), cannabigerol (CBG), cannabichromene (CBC), etc. Although it might appear as a trivial analysis, it is rather a tricky task. Phytocannabinoids are present mostly as carboxylated species at the aromatic ring of the resorcinyl moiety. Their decarboxylation caused by heat leads to a greater analytical variability due to both reaction kinetics and possible decomposition. Moreover, the instability of cannabinoids and the variability in the sample preparation, extraction, and analysis, as well as the presence of isomeric forms of cannabinoids, complicates the scenario. A critical evaluation of the different analytical methods proposed in the literature points out that each of them has inherent limitations. The present review outlines all the possible pitfalls that can be encountered during the analysis of these compounds and aims to be a valuable help for the analytical chemist. Graphical abstract.


Asunto(s)
Cannabinoides/análisis , Cannabis/química , Técnicas de Química Analítica/métodos , Inflorescencia/química , Extractos Vegetales/química , Cromatografía de Gases/métodos , Cromatografía Liquida/métodos , Espectroscopía de Resonancia Magnética/métodos , Espectrometría de Masas/métodos , Espectroscopía Infrarroja Corta/métodos
8.
Molecules ; 24(19)2019 Oct 08.
Artículo en Inglés | MEDLINE | ID: mdl-31597364

RESUMEN

Asparagus waste represents products of great interest since many compounds with high biological value are located in the lower portion of the spears. The extraction of bioactive compounds from asparagus by-products is therefore crucial for the purpose of adding value to these by-products. In this paper, bioactive peptides from asparagus waste were extracted, digested, purified and identified. In particular, Alcalase® was chosen as the enzyme to use to obtain protein hydrolysate due to its low cost and, consequently, the possibility of implementing the method on a large scale. In order to simplify the peptide extract to reach better identification, the hydrolysate was fractionated by reversed-phase chromatography in 10 fractions. Two tests were carried out for antioxidant activity (ABTS-DPPH) and one for antihypertensive activity (ACE). Fractions with a higher bioactivity score were identified by peptidomics technologies and screened for bioactivity with the use of bioinformatics. For ACE-inhibitor activity, two peptides were synthetized, PDWFLLL and ASQSIWLPGWL, which provided an EC50 value of 1.76 µmol L-1 and 4.02 µmol L-1, respectively. For the antioxidant activity, by DPPH assay, MLLFPM exhibited the lowest EC50 value at 4.14 µmol L-1, followed by FIARNFLLGW and FAPVPFDF with EC50 values of 6.76 µmol L-1 and 10.01 µmol L-1, respectively. A validation of the five identified peptides was also carried out. The obtained results showed that peptides obtained from asparagus by-products are of interest for their biological activity and are suitable for being used as functional ingredients.


Asunto(s)
Antihipertensivos/química , Antioxidantes/química , Asparagus/química , Péptidos/química , Extractos Vegetales/química , Proteómica , Secuencia de Aminoácidos , Antihipertensivos/aislamiento & purificación , Antihipertensivos/farmacología , Antioxidantes/aislamiento & purificación , Extractos Vegetales/aislamiento & purificación , Extractos Vegetales/farmacología , Proteínas de Plantas/química , Proteómica/métodos , Espectrometría de Masas en Tándem
9.
J Sep Sci ; 42(10): 1938-1947, 2019 May.
Artículo en Inglés | MEDLINE | ID: mdl-30920149

RESUMEN

An analytical method for determining seleno-methionine, methyl-seleno-cysteine, and seleno-cystine in wheat bran was developed and validated. Four different extraction procedures were evaluated to simultaneously extract endogenous free and conjugated seleno-amino acids in wheat bran in order to select the best extraction protocol in terms of seleno amino acid quantitation. The extracted samples were subjected to a clean-up by a reversed phase/strong cation exchange solid-phase extraction and analyzed by chiral hydrophilic interaction liquid chromatography-tandem mass spectrometry. The optimized extraction protocol was employed to validate the methodology. Process efficiency ranged from 58 to 112% and trueness from 73 to 98%. Limit of detection and limit of quantification were lower than 1 ng/g. Four wheat bran samples were analyzed for both total Se and single seleno-amino acids determination. The results showed that Se- seleno-methyl-lselenocysteine was the major seleno-amino acid in wheat bran while seleno-methionine and seleno-cysteine were both minor species.


Asunto(s)
Aminoácidos/análisis , Fibras de la Dieta/análisis , Análisis de los Alimentos/métodos , Selenocisteína/análisis , Calibración , Cationes , Cromatografía Liquida , Interacciones Hidrofóbicas e Hidrofílicas , Límite de Detección , Reproducibilidad de los Resultados , Selenio/análisis , Extracción en Fase Sólida , Streptomyces , Espectrometría de Masas en Tándem
10.
Anal Chem ; 90(20): 12230-12238, 2018 10 16.
Artículo en Inglés | MEDLINE | ID: mdl-30204416

RESUMEN

The work describes the chromatographic separation optimization of polar lipids on Kinetex-EVO, particularly focusing on sulfolipids in spirulina microalgae ( Arthrospira platensis). Gradient shape and mobile-phase modifiers (pH and buffer) were tested on lipid standards. Different conditions were evaluated, and resolution, peak capacity, and peak shape were calculated both in negative mode, for sulfolipids and phospholipids, and in positive mode, for glycolipids. A high-confidence lipid identification strategy was also applied. In collaboration with software creators and developers, Lipostar was implemented to improve the identification of phosphoglycerolipids and to allow the identification of glycosylmonoradyl- and glycosyldiradyl-glycerols classes, the last being the main focus of this work. By this approach, an untargeted screening also for searching lipids not yet reported in the literature could be accomplished. The optimized chromatographic conditions and database search were tested for lipid identification first on the standard mixture, then on the polar lipid extract of spirulina microalgae, for which 205 lipids were identified.


Asunto(s)
Lípidos/análisis , Microalgas/química , Spirulina/química , Concentración de Iones de Hidrógeno , Espectrometría de Masas , Extractos Vegetales/química
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