RESUMEN

The inflorescences of the Mexican gordolobo are used as a folk medicine to treat various respiratory diseases. Currently, the botanical species that bear the name Mexican gordolobo belong to the genera Gnaphalium and Pseudognaphalium. Despite a long history of traditional use, most Mexican gordolobo species have never been fully chemically characterized, and the range of constituents in the species has not been comprehensively reported. To establish a quality control and chemical characterization method, a total of 49 samples belonging to 18 species of Pseudognaphalium and four species of Gnaphalium were studied. Nine flavones were quantified using a UPLC-PDA method. The method was validated in terms of linearity (R2 > 0.99), precision (intra- and inter-day: 0.1-3.9%), accuracy (96-103%), detection limit (10 ng/mL), limit of quantification (25 ng/mL) and robustness. 3-Methylquercetin, luteolin, quercetin, 3,5-dihydroxy-6,7,8-trimethoxyflavone, apigenin and gnaphaliin A were present at relatively high levels in most of the samples analyzed. The samples of P. oxyphyllum and P. liebmannii showed the highest content of the 9 compounds analyzed. Whereas the samples of the 5 species of Gnaphalium showed the lowest levels, including non-detectable, of the 9 compounds quantified. This marks an important difference with Pseudognaphalium species. Furthermore, using UHPLC-ESI-QToF data with targeted and non-targeted approaches, 57 compounds, were identified in Mexican gordolobo samples. Flavonoids were the main group of compounds found in Mexican gordolobo.

Asunto(s)

Flavonas , Gnaphalium , Extractos Vegetales , Cromatografía Líquida de Alta Presión/métodos , Flavonas/análisis , Flavonas/química , Gnaphalium/química , Extractos Vegetales/química , Extractos Vegetales/análisis , Límite de Detección , Reproducibilidad de los Resultados , México , Control de Calidad , Medicina Tradicional/métodos , Espectrometría de Masas en Tándem/métodos , Espectrometría de Masas/métodos

RESUMEN

The ethanolic extract from leaves of Rauia resinosa, Rutaceae, provided a new flavone, 5-hydroxy-5',6,7-trimethoxy-3',4'-methylenedioxyflavone (1), in addition to four known compounds: 3',4',5,5',7-pentamethoxyflavone (2), 5,7,8-trimethoxy-3'4'-methylenedioxyflavone (3), 3',4',5,7,8-pentamethoxyflavone (4) and ß-sitosterol (5). The structures of all compounds were established on the basis of spectroscopic methods, mainly 1D and 2D NMR, UPLC-DAD-MS and UPLC-ESI-MS/MS, involving comparison with literature data. Cytotoxicity of leaves and stems extracts, their fractions and compounds (2), (3), (4) and (5) were evaluated against T24 (bladder carcinoma), TOV-21-G (ovarian adenocarcinoma) and HepG2 (liver carcinoma) cell lines.

Asunto(s)

Carcinoma , Flavonas , Rutaceae , Humanos , Espectrometría de Masas en Tándem , Flavonas/farmacología , Flavonas/análisis , Rutaceae/química , Extractos Vegetales/química , Hojas de la Planta/química

RESUMEN

Plant extracts are complex mixtures that are difficult to characterize, and mass spectrometry is one of the main techniques currently used in dereplication processes. Fridericia chica is a species with medicinal uses in Latin American countries, used in the treatment of inflammatory and infectious diseases. Extracts of this plant species are characterized by the presence of anthocyanidins. In this study, using high-resolution mass spectrometry coupled with liquid chromatography, it was possible to determine the molecular formula of thirty-nine flavonoids. Fragmentation analysis, ultraviolet spectrum and nuclear magnetic resonance data allowed the partial characterization of the structures of these compounds. The spectral dataset allowed the identification of a series of flavones in addition to the desoxyanthocyanidins common in extracts of the species. The occurrence of some of the proposed structures is uncommon in extracts of species of the Bignoniaceae family, and they are reported for the first time in the extract of this species. Quantitative analyses of total flavonoids confirmed the high content of these constituents in the species, with 4.09 ± 0.34 mg/g of dry plant material. The extract under study showed low in vitro cytotoxicity with CC50 ≥ 296.7 ± 1.4 µg/mL for Vero, LLC-MK2 and MRC-5 cell lines. In antiviral activity assays, inhibition of the cytopathic effects of Dengue, Zika and Mayaro viruses was observed, with EC50 values ranging between 30.1 and 40.9 µg/mL. The best result was observed against the Mayaro virus, with an EC50 of 30.1 µg/mL.

Asunto(s)

Bignoniaceae , Flavonas , Infección por el Virus Zika , Virus Zika , Antocianinas/análisis , Antivirales/análisis , Antivirales/farmacología , Bignoniaceae/química , Flavonas/análisis , Flavonas/farmacología , Flavonoides/análisis , Flavonoides/farmacología , Espectrometría de Masas , Extractos Vegetales/química , Hojas de la Planta/química

RESUMEN

Lophophytum species are holoparasites that grow on tree roots. The objectives of the work were to explore the chemical composition of the tubers of two Lophophytum species and to analyze the antioxidant, anti-inflammatory and antilithiatic activity of their extracts using in vitro methods. The chemical composition was determined by histochemical, phytochemical and TLC tests. In addition, the profile of phenolic compounds was determined by HPLC-MS. The presence of secondary metabolites of recognized activity was demonstrated. The results of the HPLC-MS/MS allowed the tentative identification of catechin, luteolin and glycosides of eriodictyol, naringenin and luteolin in the extract of Lophophytum leandriand eriodictyol, naringenin, luteolin and their glycosylated derivatives in Lophophytum mirabile. The extracts showed promising antioxidant (DPPH, ABTS and ß-carotene-linoleic acid), anti-inflammatory (inhibition of 5-LOX) and anti-urolytic (by bioautographic TLC) activity. It is noteworthy that these are the first results of the phytochemical composition and biological activity of L. mirabile. However, in vivo studies are required to corroborate these activities.

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Las especies de Lophophytumson holoparásitas que crecen en raíces de árboles. Los objetivos del trabajo fueron explorar la composición química del túber de dos especies de Lophophytum y analizar la actividad antioxidante, antiinflamatoria y antilitiásica de sus extractos usando métodos in vitro. La composición química se determinó mediante pruebas histoquímicas, fitoquímicas y por TLC. Además, se determinó el perfil de compuestos fenólicos por HPLC-MS/MS. Se demostró presencia de metabolitos secundarios de reconocida actividad. Los resultados del HPLC-MS/MS permitieron identificar tentativamente catequina, luteolina y glucósidos de eriodictiol, naringenina y luteolina en el extracto de Lophophytum leandriy eriodictiol, naringenina, luteolina y sus derivados glicosilados en Lophophytum mirabile. Los extractos mostraron prometedora actividad antioxidante (DPPH, ABTS y ß-caroteno-ácido linoleico), antiinflammatoria (inhibición de la 5-LOX) y antiurolitiásica (por TLC bioautográfica). Es de destacar que estos son los primeros resultados de composición fitoquímica y actividad biológica de L. mirabile. Sin embargo, se requieren estudios in vivo para corroborar dichas actividades.

Asunto(s)

Extractos Vegetales/farmacología , Extractos Vegetales/química , Balanophoraceae/química , Cromatografía Líquida de Alta Presión , Flavanonas/análisis , Flavonas/análisis , Compuestos Fenólicos/análisis , Espectrometría de Masas en Tándem , Antiinflamatorios/farmacología , Antiinflamatorios/química , Antioxidantes/farmacología , Antioxidantes/química

RESUMEN

OBJECTIVES: This study was carried out to evaluate the effects of flavonoids present in leaves of Passiflora edulis fruit on complications induced by diabetes in rats. METHODS: The extract of P. edulis leaf was obtained by 70% ethanol maceration. From the dry extract, the fractions were obtained by consecutive liquid-liquid partition with hexane, ethyl acetate and n-butanol. The content of isoorientin of ethyl acetate and n-butanol fractions was determined by ultra-performance liquid chromatography coupled with electrospray and triple quadrupole ionization (TQD) analysis in tandem mass spectrometry (UPLC-ESI-Tq-MS). Only Fr-BuOH was used to treat diabetic or not Wistar rats. Biochemical parameters, platelet aggregation and production of reactive species were evaluated. KEY FINDINGS: The UPLC-ESI-Tq-MS analysis revealed the presence of several flavonoids, among which we identified five possible flavonoids c-heterosides (luteolin-7-O-pyranosyl-3-O-glucoside, apigenin-6-8-di-C-glycoside, apigenin-6-C-arabinoside-8-C-glycoside, isoorientin, isovitexin). The diabetic rats (treated intraperitoneally with alloxan, 150 mg/kg) treated with Fr-BuOH (20 mg/kg/day for 90 days) presented improvement in blood glucose, serum levels of fructosamine, lipid profile and urea. Furthermore, the Fr-BuOH reduced both platelet aggregation and the production of oxidant species in diabetic animals. CONCLUSIONS: These results suggested that flavonoid C-glycosides present in the Fr-BuOH may be beneficial for the diabetic state, preventing complications induced by diabetes.

Asunto(s)

Complicaciones de la Diabetes/prevención & control , Diabetes Mellitus Experimental/tratamiento farmacológico , Flavonoides/uso terapéutico , Glicósidos/uso terapéutico , Passiflora/química , Fitoterapia , Extractos Vegetales/uso terapéutico , Animales , Antioxidantes/farmacología , Antioxidantes/uso terapéutico , Apigenina/análisis , Apigenina/farmacología , Apigenina/uso terapéutico , Glucemia/metabolismo , Cromatografía Líquida de Alta Presión , Complicaciones de la Diabetes/sangre , Diabetes Mellitus Experimental/sangre , Diabetes Mellitus Experimental/complicaciones , Flavonas/análisis , Flavonas/farmacología , Flavonas/uso terapéutico , Flavonoides/análisis , Flavonoides/farmacología , Fructosamina/sangre , Glucósidos/análisis , Glucósidos/farmacología , Glucósidos/uso terapéutico , Glicósidos/análisis , Glicósidos/farmacología , Luteolina/análisis , Luteolina/farmacología , Luteolina/uso terapéutico , Masculino , Extractos Vegetales/química , Extractos Vegetales/farmacología , Hojas de la Planta/química , Agregación Plaquetaria/efectos de los fármacos , Ratas Wistar , Espectrometría de Masas en Tándem

RESUMEN

A phytochemical and antibacterial study of Trixis angustifolia, a species endemic to Mexico, was performed allowing the isolation of six flavones. The minimal inhibitory concentration (MIC) of the hexanic extract, against Mycobacterium tuberculosis H37Rv was 25 µg/mL. The hexanic extract caused a significant inhibition of intracellular mycobacterial growth at 12.5 µg/mL. The biodirected assay of hexane extract enabled the detection of an active fraction (AF) against M. tuberculosis (MIC = 12.5 µg/mL), and a major flavone 1 (pebrellin) with no antimycobacterial activity (MIC > 200 µg/mL). A subsequent combination antimicrobial assay showed a synergistic antimycobacterial effect of AF in combination with pebrellin; the results of the synergistic activity suggest that the antimycobacterial activity found in T. angustifolia is due to the combined action of diverse metabolites present in the plant.

Asunto(s)

Antituberculosos/farmacología , Asteraceae/química , Mycobacterium tuberculosis/efectos de los fármacos , Extractos Vegetales/farmacología , Sinergismo Farmacológico , Flavonas/análisis , Flavonas/aislamiento & purificación , Flavonas/farmacología , Hexanos/química , México , Pruebas de Sensibilidad Microbiana , Extractos Vegetales/química

RESUMEN

Lippia alba is a popular Brazilian herb known as 'cidreira' that presents several chemotypes which exhibit different chemical profile and they are widely used as seasonings and traditional medicine. This work describes the seasonal variation of metabolites of polar extracts of carvone and linalool chemotypes, identified by GC-MS analyses of the essential oils. A methodology was elaborated in order to obtain a seasonal variation in the chemical composition of leaf employing HPLC-DAD. Acteoside, isoacteoside, geneposidic acid, 8-epi-loganin, mussaenoside, luteolin 7-O-glucoside, apigenin 7-O-glucuronide and tricin 7-O-diglucuronide have been isolated and identified for validation procedures and chromatographic analysis. Geneposidic acid was presented in all samples, in contrast to the 8-epi-loganin and, mussaenoside which were presented only in the carvone-chemotype. Acteoside was the major metabolite detected from July to November while tricin-7-O-diglucuronide was the major compound in all other months. Besides, phenylpropanoids are predominant in winter and flavonoids in summer season.

Asunto(s)

Flavonoides/análisis , Glucurónidos/análisis , Lippia/química , Aceites Volátiles/análisis , Aceites Volátiles/química , Monoterpenos Acíclicos , Brasil , Cromatografía Líquida de Alta Presión , Flavonas/análisis , Cromatografía de Gases y Espectrometría de Masas , Glucósidos/análisis , Monoterpenos/análisis , Fenoles/análisis , Hojas de la Planta/química , Reproducibilidad de los Resultados , Estaciones del Año , Metabolismo Secundario

RESUMEN

Oxidative stress plays the central role in the pathogenesis and progression of diabetic complications. The present study aims to investigate the beneficial effect of oral administration of flavone baicalein in streptozotocin-nicotinamide (STZ-NA) induced diabetic rats by measuring oxidative stress markers, antioxidant enzyme activities and expression analysis of antioxidant genes. Experimental diabetes was induced by a single intraperitoneal (i.p.) injection of STZ (55 mg /kg b.wt), 15 min after the i.p. administration of NA. At the end of the experimental period, thiobarbituric acid reactive substances (TBARS), activities of antioxidant enzymes and expression levels of superoxide dismutase (SOD), catalase (CAT), glutathione (GSH) and glutathione peroxidase (GPx) were measured in diabetic rats along with serum biochemical parameters namely total cholesterol (TC), total triglyceride (TG), aspartate transaminase (AST) alanine transaminase (ALT) and glycosylated hemoglobin (HbA1c). Oral administration of baicalein (40 mg/kg b.wt/day) demonstrated a significant ameliorative effect on all studied biochemical and oxidative stress parameters. Biochemical findings were corroborated by qPCR expression analysis which showed significant upregulation of antioxidant genes in diabetic rats. These results suggest that baicalein supplementation may reduce diabetes and its complications by suppressing oxidative stress and enhancing gene expression and antioxidant enzyme activities in diabetic rats.

Asunto(s)

Animales , Masculino , Preescolar , Ratas , Expresión Génica , Niacinamida/farmacología , Flavonas/análisis , Diabetes Mellitus Experimental/prevención & control , Expresión Génica/efectos de los fármacos , Gliburida/farmacología , Estrés Oxidativo , Antioxidantes/farmacología

RESUMEN

"Quelites" are edible plants that are part of the traditional agro-ecosystems in Mexico. These plants, despite their already known nutritional properties, are now considered neglected and underutilized species. With the objective of promoting their reinsertion in the markets and mainly, in daily diets, efforts have been made to study them from multidisciplinary approaches to demonstrate their beneficial properties. To generate evidence of an added health-promoting value that would encourage quelites consumption, in the present work, the anti-Helicobacter pylori activity of three representative quelite species, Anoda cristata (Alache), Cnidoscolus aconitifolius (Chaya), and Crotalaria pumila (Chepil), was tested. H. pylori is considered the etiological agent of gastritis, ulcer, and gastric cancer, and represents a public health problem in Mexico and worldwide. Aqueous (AQ) and dichloromethane-methanol (DM) extracts were obtained from the three species of quelites to investigate their effect on H. pylori growth and on two of its colonization factors (adherence and urease activity). DM extracts from Chaya, Chepil, and Alache exert the best inhibitory effect on bacterial growth, with minimum inhibitory concentrations of 62.5, 125, and 250 µg/mL, respectively. AQ and DM extracts inhibit bacterial adhesion by 30% to 50%. None of them has an effect on urease activity. The two flavonoids present in A. cristata, acacetin and diosmetin, inhibit H. pylori growth by ∼90% with 3.9 µg/mL. These results provide new information about the anti-H. pylori potential of three edible quelites, and give an added value, since their routine consumption may impact on the prevention and/or control of H. pylori-associated diseases.

Asunto(s)

Antibacterianos/farmacología , Crotalaria/química , Euphorbiaceae/química , Infecciones por Helicobacter/microbiología , Helicobacter pylori/efectos de los fármacos , Malvaceae/química , Extractos Vegetales/farmacología , Antibacterianos/química , Antibacterianos/aislamiento & purificación , Flavonas/análisis , Flavonas/farmacología , Flavonoides/farmacología , Helicobacter pylori/crecimiento & desarrollo , Humanos , México , Pruebas de Sensibilidad Microbiana , Extractos Vegetales/química , Extractos Vegetales/aislamiento & purificación , Plantas Comestibles/química

RESUMEN

The aim of this study was to develop and validate an HPLC-DAD method to evaluate the phenolic compounds profile of organic and conventional Pêra-Rio orange juice. The proposed method was validated for 10 flavonoids and 6 phenolic acids. A wide linear range (0.01-223.4µg·g-1), good accuracy (79.5-129.2%) and precision (CV≤3.8%), low limits of detection (1-22ng·g-1) and quantification (0.7-7.4µg), and overall ruggedness were attained. Good recovery was achieved for all phenolic compounds after extraction and cleanup. The method was applied to organic and conventional Pêra-Rio orange juices from beginning, middle and end of the 2016 harvest. Flavones rutin, nobiletin and tangeretin, and flavanones hesperidin, narirutin and eriocitrin were identified and quantified in all organic and conventional juices. Identity was confirmed by mass spectrometry. Nineteen non-identified phenolic compounds were quantified based on DAD spectra characteristic of the chemical class: 7 cinnamic acid derivatives, 6 flavanones and 6 flavones. The phenolic compounds profile of Pêra-Rio orange juices changed during the harvest; levels increased in organic orange juices, and decreased or were about the same in conventional orange juices. Phenolic compounds levels were higher in organic (0.5-1143.7mg·100g-1) than in conventional orange juices (0.5-689.7mg·100g-1). PCA differentiated organic from conventional FS and NFC juices, and conventional FCOJ from conventional FS and NFC juices, thus differentiating cultivation and processing.

Asunto(s)

Cromatografía Líquida de Alta Presión/métodos , Citrus sinensis/química , Flavonoides/análisis , Jugos de Frutas y Vegetales/análisis , Frutas/química , Fenoles/análisis , Disacáridos/análisis , Flavanonas/análisis , Flavonas/análisis , Análisis de los Alimentos/métodos , Hesperidina/análisis , Humanos , Reproducibilidad de los Resultados

RESUMEN

BACKGROUND: Thevetia peruviana (Pers.) K. Schum or Cascabela peruviana (L.) Lippold (commonly known as ayoyote, codo de fraile, lucky nut, or yellow oleander), native to Mexico and Central America, is a medicinal plant used traditionally to cure diseases like ulcers, scabies, hemorrhoids and dissolve tumors. The purpose of this study was to evaluate the cytotoxic, antiproliferative and apoptotic activity of methanolic extract of T. peruviana fruits on human cancer cell lines. METHODS: The cytotoxic activity of T. peruviana methanolic extract was carried out on human breast, colorectal, prostate and lung cancer cell lines and non-tumorigenic control cells (fibroblast and Vero), using the MTT assay. For proliferation and motility, clonogenic and wound-healing assays were performed. Morphological alterations were monitored by trypan blue exclusion, as well as DNA fragmentation and AO/EB double staining was performed to evaluate apoptosis. The extract was separated using flash chromatography, and the resulting fractions were evaluated on colorectal cancer cells for their cytotoxic activity. The active fractions were further analyzed through mass spectrometry. RESULTS: The T. peruviana methanolic extract exhibited cytotoxic activity on four human cancer cell lines: prostate, breast, colorectal and lung, with values of IC50 1.91 ± 0.76, 5.78 ± 2.12, 6.30 ± 4.45 and 12.04 ± 3.43 µg/mL, respectively. The extract caused a significant reduction of cell motility and colony formation on all evaluated cancer cell lines. In addition, morphological examination displayed cell size reduction, membrane blebbing and detachment of cells, compared to non-treated cancer cell lines. The T. peruviana extract induced apoptotic cell death, which was confirmed by DNA fragmentation and AO/EB double staining. Fractions 4 and 5 showed the most effective cytotoxic activity and their MS analysis revealed the presence of the secondary metabolites: thevetiaflavone and cardiac glycosides. CONCLUSION: T. peruviana extract has potential as natural anti-cancer product with critical effects in the proliferation, motility, and adhesion of human breast and colorectal cancer cells, and apoptosis induction in human prostate and lung cancer cell lines, with minimal effects on non-tumorigenic cell lines.

Asunto(s)

Antineoplásicos Fitogénicos/uso terapéutico , Glicósidos Cardíacos/uso terapéutico , Flavonas/uso terapéutico , Neoplasias/tratamiento farmacológico , Fitoterapia , Extractos Vegetales/uso terapéutico , Thevetia/química , Animales , Antineoplásicos Fitogénicos/farmacología , Apoptosis , Neoplasias de la Mama/tratamiento farmacológico , Glicósidos Cardíacos/análisis , Glicósidos Cardíacos/farmacología , Línea Celular Tumoral , Proliferación Celular , Neoplasias Colorrectales/tratamiento farmacológico , Fragmentación del ADN , Femenino , Flavonas/análisis , Flavonas/farmacología , Frutas , Humanos , Neoplasias Pulmonares/tratamiento farmacológico , Masculino , México , Extractos Vegetales/farmacología , Neoplasias de la Próstata/tratamiento farmacológico , Células Vero

RESUMEN

ETHNOPHARMACOLOGICAL RELEVANCE: Agastache mexicana has been used in traditional medicine for relief of abdominal pain and treatment of other diseases. Two subspecies have been identified: A. mexicana ssp. mexicana (AMM) and A. mexicana ssp. xolocotziana (AMX) and both are used traditionally without distinction or in combination. AIM OF THE STUDY: To determine the effect of methanol extracts of A. mexicana ssp. mexicana and A. mexicana ssp. xolocotziana on gut motility and their possible mechanism of action. MATERIALS AND METHODS: The effect of AMM and AMX methanol extracts were tested on the spontaneous activity in the isolated guinea pig ileum and on tissues pre-contracted with KCl, electrical field stimulation (EFS) or ACh. In addition, the possible mechanism of action of each subspecies on gut motility was analyzed in the presence of hexametonium, indomethacin, L-NAME, verapamil, atropine or pyrylamine. A comparative chromatographic profile of these extracts was also done to indicate the most abundant flavonoids presents in methanol extracts of both subspecies. RESULTS: AMM, but not AMX, induced a contractile effect in the guinea pig ileum. This spasmogenic effect was partially inhibited by atropine, antagonist of muscarinic receptors; and pyrilamine, antagonist of H1 receptors. In contrast, AMX, but not AMM, diminished the contractions induced by KCl, EFS or ACh. The spasmolytic activity of AMX was partially inhibited by hexamethonium, ganglionic blocker; and indomethacin, inhibitor of the synthesis of prostaglandins; but not by L-NAME, inhibitor of nitric oxide synthase. In addition, AMX diminished the maximal contraction induced by CaCl2 in a calcium-free medium. Chromatographic analyses of these methanol extracts showed the presence of acacetin and tilanin in both. CONCLUSIONS: These results suggest that in folk medicine only AMX should be used as spasmolytic, and not in combination with AMM as traditionally occurs, due to the spasmogenic effects of the latter. In addition, activation of nicotinic receptors, prostaglandins and calcium channels, but not nitric oxide mechanisms, could be responsible for the spasmolytic activity of AMX. On the other hand, release of ACh and histamine could be involved in the spasmogenic effect induced by AMM. Acacetin and tilanin are present in methanol extracts of both subspecies and both flavonoids were more abundant in AMX than AMM. Our findings contribute to the validation of the traditional use of Agastache mexicana in relieving gastrointestinal disorders, but indicate that the subspecie that should be used for this effect is A. mexicana ssp. xolocotziana.

Asunto(s)

Agastache , Íleon/efectos de los fármacos , Parasimpatolíticos/farmacología , Extractos Vegetales/farmacología , Animales , Flavonas/análisis , Flavonas/farmacología , Flavonoides/análisis , Flavonoides/farmacología , Flores , Glicósidos/análisis , Glicósidos/farmacología , Cobayas , Íleon/fisiología , Técnicas In Vitro , Masculino , Metanol/química , Contracción Muscular/efectos de los fármacos , Músculo Liso/efectos de los fármacos , Músculo Liso/fisiología , Parasimpatolíticos/análisis , Extractos Vegetales/análisis , Solventes/química

RESUMEN

Ageratum conyzoides L. is a plant widely used in traditional medicine of tropical and subtropical regions for its anti-inflammatory and antinociceptive properties. Nevertheless, the chemical composition of its medicinal preparation has not been yet accurately established. In this study, chromatographic methods were developed for the simultaneous identification and quantification of the main compounds in A. conyzoides aqueous extract, using UPLC-PDA-ESI-QToF-MS. The qualitative analyses defined by MS/MS analysis allowed the identification of 27 compounds in the aqueous extract, including the toxic pyrrolizidine alkaloids, phenolic acids, coumarin and polymethoxyflavones. Among the metabolites, twelve were detected for the first time in the species. The quantitative method was validated according to the official guidelines, demonstrating to be specific, linear, precise, accurate and sensitive for the quantification of chlorogenic acid, coumaric acid, coumarin (1,2-benzopyranone), 5,6,7,3',4',5'-hexamethoxyflavone, nobiletin, 5'-methoxynobiletin and eupalestin.

Asunto(s)

Ageratum/química , Cromatografía Líquida de Alta Presión/métodos , Cumarinas/análisis , Flavonas/análisis , Hidroxibenzoatos/análisis , Espectrometría de Masa por Ionización de Electrospray/métodos , Espectrometría de Masas en Tándem/métodos , Cromatografía Líquida de Alta Presión/instrumentación , Extractos Vegetales/análisis , Extractos Vegetales/química , Hojas de la Planta/química

RESUMEN

Overall phenolic content in plants is on average higher in organic farming, including when renewable resources such as composts are used as soil amendments. In most cases, however, the composting process needs to be optimized to reach the desired outcome. Using composts obtained from chestnut, red and white grapes, olive and broccoli wastes, the relative antioxidative abilities of lettuces cultivated in greenhouse were examined. Results clearly coupled high phenolic levels with high yield in lettuce grown on the chestnut-based compost. A huge accumulation of phenolics was observed with the white grape-based compost, but this coincided with low yield. Three compounds were identified as discriminating factors between treated samples, namely quercetin 3-O-glucoside, luteolin 7-O-glucoside, and cyanidin 3-O-(6″-malonyl)-ß-d-glucoside; these are also some of the compounds receiving health claims on lettuce consumption. On a negative note, all composts led to decreased vitamin C levels. Collectively, the data suggest that compost amendments can help add value to lettuce by increasing its antioxidant activity as compared to other organic resources.

Asunto(s)

Ácido Ascórbico/análisis , Fertilizantes , Residuos Industriales , Lactuca/crecimiento & desarrollo , Agricultura Orgánica/métodos , Fenoles/análisis , Suelo/química , Antocianinas/análisis , Antioxidantes/análisis , Flavonas/análisis , Flavonoides/análisis , Glucósidos/análisis , Lactuca/química , Olea/química , Quercetina/análogos & derivados , Vitis/química

RESUMEN

OBJECTIVE: To evaluate the phytochemical composition of hydroethanolic extracts from powdered aerial parts of Turnera diffusa Willd (Turneraceae; T. diffusa), as well as its toxicity in astrocytes. METHODS: Chemical analyses of hydroethanolic extract from powdered aerial parts ofT. diffusa were carried out using HPLC-DAD-ESI-MS/MS.In vitro assays using astrocytes culture were performed to evaluate cell death. RESULTS: Flavone-C, O-diglycosides, such as, luteolin-8-C-[6-deoxy-2-O-rhamnosyl]-xylo-hexos-3-uloside, apigenin-8-C-[6-deoxy-2-O-rhamnosyl]-xylo-hexos-3-uloside and apigenin-7-O-6"-p-coumaroylglucoside were the main compounds found in this hydroethanolic extract. Concentration time-effect demonstrated the toxicity of this extract at a concentration of 1,000µg/mL in astrocyte culture, after 6 and 24 hours of incubation. CONCLUSION: In phytochemical analyses, important antioxidants (mainly flavonoids) were observed. T. diffusa extracts presented cytotoxic effect in high concentrations, leading to increased cell death in astrocyte culture.

Asunto(s)

Antioxidantes/química , Astrocitos/efectos de los fármacos , Extractos Vegetales/química , Turnera/química , Animales , Astrocitos/química , Muerte Celular/efectos de los fármacos , Cromatografía Líquida de Alta Presión/métodos , Flavonas/análisis , Flavonas/toxicidad , Extractos Vegetales/toxicidad , Ratas , Espectrometría de Masa por Ionización de Electrospray/métodos

RESUMEN

ABSTRACT Objective To evaluate the phytochemical composition of hydroethanolic extracts from powdered aerial parts of Turnera diffusa Willd (Turneraceae; T. diffusa), as well as its toxicity in astrocytes. Methods Chemical analyses of hydroethanolic extract from powdered aerial parts ofT. diffusa were carried out using HPLC-DAD-ESI-MS/MS.In vitro assays using astrocytes culture were performed to evaluate cell death. Results Flavone-C, O-diglycosides, such as, luteolin-8-C-[6-deoxy-2-O-rhamnosyl]-xylo-hexos-3-uloside, apigenin-8-C-[6-deoxy-2-O-rhamnosyl]-xylo-hexos-3-uloside and apigenin-7-O-6”-p-coumaroylglucoside were the main compounds found in this hydroethanolic extract. Concentration time-effect demonstrated the toxicity of this extract at a concentration of 1,000µg/mL in astrocyte culture, after 6 and 24 hours of incubation. Conclusion In phytochemical analyses, important antioxidants (mainly flavonoids) were observed. T. diffusa extracts presented cytotoxic effect in high concentrations, leading to increased cell death in astrocyte culture.

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RESUMO Objetivo Avaliar a composição fitoquímica do extrato hidroetanólico das partes aéreas de Turnera diffusa Willd (Turneraceae; T. diffusa) e sua toxicidade em astrócitos. Métodos Análises químicas do extrato hidroetanólico de partes aéreas de T. diffusa foram feitas por HPLC-DAD-ESI-MS/MS. Os ensaiosin vitro utilizaram culturas de astrócitos para avaliar morte celular. Resultados Flavonas-C, O-diglicosídeos, como, luteolina-8-C-[6-deoxi-2-O-raminosil]-xilo-hexos-3-ulosideo, apigenina-8-C-[6-deoxi-2-O-raminosil]-xilo-hexos-3-ulosideo e apigenina-7-O-6”-p-cumaroilglucosídeo foram os principais constituintes encontrados neste extrato hidroetanólico. Uma curva tempo-concentração demonstrou toxicidade desse extrato na concentração de 1.000µg/mL, na cultura de astrócitos após 6 e 24 horas de incubação. Conclusão Nas análises fitoquímicas, importantes antioxidantes, sobretudo flavonoides, foram observados. Extratos de T. diffusa apresentaram efeitos citotóxicos em altas concentrações, ocasionando aumento de morte celular em cultura de astrócitos.

Asunto(s)

Animales , Ratas , Extractos Vegetales/química , Astrocitos/efectos de los fármacos , Turnera/química , Antioxidantes/química , Extractos Vegetales/toxicidad , Astrocitos/química , Cromatografía Líquida de Alta Presión/métodos , Muerte Celular/efectos de los fármacos , Espectrometría de Masa por Ionización de Electrospray/métodos , Flavonas/análisis , Flavonas/toxicidad

RESUMEN

Matrix assisted laser desorption ionization (MALDI) is a technique widely employed in the analysis of proteins and peptides, and nowadays it has also been applied to small molecules. There is little significant information regarding the in-source dissociation processes on MALDI for natural products. Twenty-six flavonoids (flavanones, flavones and flavonols) were analyzed by MALDI using different methods (with different matrices) and without matrix to comprehend the in-source reactions and establish good analysis methods for these compounds. Depending on the class, structure and the laser intensity applied, methoxylated flavonoid aglycones can eliminate methyl radicals (˙CH3) in the source, such as flavonols, but lithium 2,4-dihydroxybenzoate matrix suppresses the ˙CH3 eliminations and retro-Diels-Alder cleavages in the source. All of the flavonoid O-glycosides evaluated herein eliminated the sugar in source, even in the presence of the matrix, and its product radical ions ([M-H-sugar](-)˙) were observed in the negative mode. The flavone C-glycosides suffered intense dissociation, which was reduced by the addition of a matrix and the application of low laser intensity, mainly in the negative mode. Depending on the hydroxyl substituents, the [M-H-H](-)˙ ion was observed with variable relative intensity in the spectra.

Asunto(s)

Flavonoides/análisis , Espectrometría de Masa por Láser de Matriz Asistida de Ionización Desorción/métodos , Flavanonas/análisis , Flavanonas/química , Flavonas/análisis , Flavonas/química , Flavonoides/química , Flavonoles/análisis , Flavonoles/química , Glicósidos/química , Hidroxibenzoatos/química , Estructura Molecular

RESUMEN

This paper reports a comparison of four Phyllanthus species (P. amarus, P. stipulatus, P. niruri and P. tenellus), commonly known as stone breaker, by the characterization of the chemical profile of their aqueous extracts. Such characterization was carried out using liquid chromatography coupled to ion trap tandem mass spectrometry (LC-IT-MS(n)) under reversed-phase gradient elution mode. The results of MS/MS and MS(3) on-line experiments, using the electrospray ionization source in the positive and negative mode, are extensively discussed. Furthermore, quercetin-3-O-ß-d-glucuronopyranoside was isolated in multimilligram scale from the aqueous extract of P. stipulatus and characterized by mass spectrometry and NMR. Although it is an unusual flavonol in natural products, LC-IT-MS(n) experiments showed it to be present also in P. amarus.

Asunto(s)

Cromatografía Liquida/métodos , Phyllanthus/química , Phyllanthus/clasificación , Extractos Vegetales/química , Espectrometría de Masas en Tándem/métodos , Flavonas/análisis , Flavonas/química , Flavonoles/análisis , Flavonoles/química , Taninos Hidrolizables/análisis , Taninos Hidrolizables/química , Espectrometría de Masa por Ionización de Electrospray

RESUMEN

Tissue damage due to oxidative stress is directly linked to development of many, if not all, human morbidity factors and chronic diseases. In this context, the search for dietary natural occurring molecules with antioxidant activity, such as flavonoids, has become essential. In this study, we investigated a set of 41 flavonoids (23 flavones and 18 flavonols) analyzing their structures and biological antioxidant activity. The experimental data were submitted to a QSAR (quantitative structure-activity relationships) study. NMR 13C data were used to perform a Kohonen self-organizing map study, analyzing the weight that each carbon has in the activity. Additionally, we performed MLR (multilinear regression) using GA (genetic algorithms) and molecular descriptors to analyze the role that specific carbons and substitutions play in the activity.

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Danos aos tecidos devido ao estresse oxidativo estão diretamente ligados ao desenvolvimento de muitos, senão todos, os fatores de sedentarismo e de doenças crônicas. Neste contexto, a busca de moléculas naturais, que participam da nossa dieta e que possuam atividade antioxidante, flavonóides, torna-se de grande interesse. Neste estudo, nós investigamos um conjunto de 41 flavonóides (23 flavonas e 18 flavonóis), relacionando suas estruturas e atividade antioxidante. Os dados experimentais foram submetidos à análise de QSAR (relações quantitativas estrutura-atividade). Dados de RMN 13C foram utilizados para realizar um estudo do mapa auto-organizável de Kohonen, analisando o peso que cada carbono tem na atividade. Além disso, realizamos uma MLR (regressão múltipla) usando GA (algoritmos genéticos) e descritores moleculares para avaliar a influência de carbonos e substituições na atividade.

Asunto(s)

Antioxidantes/química , Espectroscopía de Resonancia Magnética/métodos , Flavonoides/análisis , Flavonoides/química , Relación Estructura-Actividad , Flavonas/análisis , Flavonas/química , Flavonoles/análisis , Flavonoles/química , Estructura Molecular

RESUMEN

Eriocaulaceae is a pantropical family that comprises about 1100 species distributed in 11 genera. The infrafamilial relationships are still unsatisfactorily resolved, because of the tiny flowers and generalized morphology, which makes the taxonomy very difficult. Flavonoid and naphthopyranone profiles have proved to be important in order to contribute to the alignment of genera into the family. We here present a survey of the chemical data of Eriocaulaceae with a discussion about their contribution to the taxonomy of Eriocaulaceae.

Asunto(s)

Eriocaulaceae/química , Flavonas/análisis , Eriocaulaceae/clasificación , Flavonas/química , Flavonoides/química , Flavonoides/aislamiento & purificación , Modelos Moleculares , Conformación Molecular , Relación Estructura-Actividad , Xantonas/análisis , Xantonas/química