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1.
Food Chem ; 336: 127701, 2021 Jan 30.
Artigo em Inglês | MEDLINE | ID: mdl-32781354

RESUMO

This study presents innovative research for comparison of the effect of the different dehydration techniques and methods of extraction on the antioxidant potential and bioactive compounds of Conilon and Arabica coffee flowers. The compounds were analyzed by high performance liquid chromatography and the antioxidant capacity evaluated by the 2,2'-azinobis (3-ethylbenzthiazoline-6-sulfonic acid) (ABTS), 2,2-diphenyl-1-picrylhydrazyl (DPPH) and nitric oxide assays. Among the compounds evaluated, trigonelline, gallic acid, chlorogenic acid, and caffeine were identified, with trigonelline and caffeine being those with the highest concentration. The investigated factors significantly influenced the profile of the bioactive compounds identified, and the antioxidant capacity. The 92 °C infusion of freeze-dried Conilon coffee flowers, in general, showed greater antioxidant capacity by ABTS and DPPH assays, as well as total phenolic content. Lyophilization had a positive influence on maintaining the content of phenolic compounds and antioxidant capacity of the samples. Coffee flowers proved to be a potential raw material for making tea-like drinks.


Assuntos
Antioxidantes/farmacologia , Coffea/química , Flores/química , Alcaloides/análise , Antioxidantes/química , Cafeína/análise , Ácido Clorogênico/análise , Cromatografia Líquida de Alta Pressão , Liofilização , Fenóis/análise , Extratos Vegetais/química
2.
Food Chem ; 334: 127552, 2021 Jan 01.
Artigo em Inglês | MEDLINE | ID: mdl-32795786

RESUMO

Extracts of Opuntia stricta var. dillenii fruits were fractionated by semi-preparative high-performance countercurrent chromatography (HPCCC) to study the secondary metabolite formation, whereby HPCCC showed a superior separation capacity to fractionate minor metabolites compared to HPLC. A family of new peptides was detected in semi-polar fractions when monitoring the HPCCC separation by off-line injections of fractions to ESI-MS/MS. Planar structures of the major compounds, two 14-ring-membered cyclopeptide alkaloids, which were named opuntisines A and B, were elucidated by 1D- and 2D-NMR spectroscopy and HR-ESI-MS/MS spectrometry, while a combination of chemical derivatisation and degradation revealed the stereo-configurations. Specifically, the methods of Marfey and Mosher indicated l-Glu, l-Ile, l-Phe and 1S-configurations, respectively; ROESY correlations revealed 8S, 9S. The novel opuntisine A showed moderate activity against the Gram-negative bacterium Escherichia coli, but no further antibacterial, antifungal nor cytotoxic effects. This bioactive natural product class is reported for the first time in the plant family Cactaceae.


Assuntos
Alcaloides/análise , Cromatografia Líquida de Alta Pressão/métodos , Opuntia/química , Peptídeos Cíclicos/química , Alcaloides/química , Alcaloides/farmacologia , Distribuição Contracorrente , Escherichia coli/efeitos dos fármacos , Frutas/química , Frutas/metabolismo , Espectroscopia de Ressonância Magnética , Conformação Molecular , Opuntia/metabolismo , Extratos Vegetais/química , Espectrometria de Massas em Tandem
3.
J Chromatogr A ; 1626: 461359, 2020 Aug 30.
Artigo em Inglês | MEDLINE | ID: mdl-32797838

RESUMO

The enantiomeric determination of chiral drugs in the environment is of emerging concern since their enantiomers often exhibit stereoselectivity in environmental occurrence, fate and toxicity. In this study a method based on solid-phase extraction followed by chiral liquid chromatography and high-resolution mass spectrometry has been developed for the enantiomeric determination of a group of cathinones in river water and effluent wastewater. The enantioseparation was carried out using a Chiralpak CBH column in reversed-phase mode, and optimised by evaluating the effects of flow rate, buffer concentration and organic modifier. Under optimal conditions, good enantioseparations (Rs ≥1.2) were achieved for all the analytes. Two mixed-mode cation-exchange sorbents (Oasis WCX and Oasis MCX) in solid-phase extraction were evaluated in river water. Oasis MCX sorbent showed better performance with apparent recoveries ranging from 57 to 91% and matrix effect ranging from -10 to 15%. It is worth noting that a shifting of retention times and loss of enantioresolutions in environmental water samples was observed for all the analytes when the Oasis WCX sorbent was used. The method was validated with river water and effluent wastewater samples and its overall performance was satisfactory. The method quantification limits for all the analyte enantiomers ranged from 1.0 to 2.9 ng/L in river water, and from 2.3 to 6.0 ng/L in effluent wastewater. The repeatability and reproducibility values, expressed as% relative standard deviation (n = 5) were less than 15%. The method was then applied to the analysis of river water and effluent wastewater. The racemic methylone and methedrone (EF=0.49 and 0.46, respectively) were detected at low ng/L in some of the river water samples.


Assuntos
Alcaloides/análise , Cromatografia Líquida/métodos , Espectrometria de Massas/métodos , Alcaloides/química , Alcaloides/isolamento & purificação , Reprodutibilidade dos Testes , Rios/química , Extração em Fase Sólida/métodos , Estereoisomerismo , Águas Residuárias/química , Poluentes Químicos da Água/análise , Poluentes Químicos da Água/química , Poluentes Químicos da Água/isolamento & purificação
4.
J Chromatogr A ; 1626: 461361, 2020 Aug 30.
Artigo em Inglês | MEDLINE | ID: mdl-32797840

RESUMO

The alkaloid enantiomers are well-known to have different physiological and pharmacological effects, and to play an important role in enantioselectivity metabolism with enzymes catalysis in tobacco plants. Here, we developed an improved method for simultaneous and high-precision determination of the individual enantiomers of nornicotine, anatabine and anabasine in four tobacco matrices, based on an achiral gas chromatography-nitrogen phosphorus detector (GCNPD) with commonly available Rtx-200 column using (1S)-(-)-camphanic chloride derivatization. The method development consists of the optimization of extraction and derivatization, screening of achiral column, analysis of the fragmentation mechanisms and evaluation of matrix effect (ME). Under the optimized experimental conditions, the current method exhibited excellent detection capability for the alkaloid enantiomers, with coefficients of determination (R2) > 0.9989 and normality test of residuals P > 0.05 in linear regression parameters. The ME can be neglected for the camphanic derivatives. The limit of detection (LOD) and limit of quantitation (LOQ) ranged from 0.087 to 0.24 µg g - 1 and 0.29 to 0.81 µg g - 1, respectively. The recoveries and within-laboratory relative standard deviations (RSDR) were 94.3%~104.2% and 0.51%~3.89%, respectively. The developed method was successfully applied to determine the enantiomeric profiling of cultivars and curing processes. Tobacco cultivars had a significant impact on the nornicotine, anatabine, anabasine concentration and enantiomeric fraction (EF) of (R)-nornicotine, whereas the only significant change induced by the curing processes was an increase in the EF of (R)-anabasine.


Assuntos
Alcaloides/análise , Anabasina/análise , Cromatografia Gasosa/métodos , Nicotina/análogos & derivados , Piridinas/análise , Tabaco/química , Alcaloides/química , Anabasina/química , Hidrocarbonetos Aromáticos com Pontes/química , Cloretos/química , Lactonas/química , Nicotina/análise , Nicotina/química , Piridinas/química , Estereoisomerismo
5.
Food Chem ; 332: 127412, 2020 Dec 01.
Artigo em Inglês | MEDLINE | ID: mdl-32623128

RESUMO

In this study, metabolomics and proteomics were employed to investigate the change mechanism of nonvolatile compounds during white tea processing. A total of 99 nonvolatile compounds were identified, among which the contents of 13 free amino acids, caffeine, theaflavins, 7 nucleosides and nucleotides, and 5 flavone glycosides increased significantly, while the contents of theanine, catechins, theasinesins, 3 proanthocyanidins, and phenolic acids decreased significantly during the withering period. The results of proteomics indicated that the degradation of proteins accounted for the increase in free amino acid levels; the weakened biosynthesis, in addition to oxidation, also contributed to the decrease in flavonoid levels; the degradation of ribonucleic acids contributed to the increase in nucleoside and nucleotide levels during the withering period. In addition, the drying process was found to slightly promote the formation of white tea taste. Our study provides a novel characterization of white tea taste formation during processing.


Assuntos
Camellia sinensis/química , Metabolômica/métodos , Chá/química , Alcaloides/análise , Alcaloides/metabolismo , Camellia sinensis/metabolismo , Catecóis/análise , Catecóis/metabolismo , Flavonoides/análise , Flavonoides/metabolismo , Folhas de Planta/química , Folhas de Planta/metabolismo , Proteínas de Plantas/metabolismo , Análise de Componente Principal , Proteômica , Chá/metabolismo
6.
Food Chem ; 331: 127260, 2020 Nov 30.
Artigo em Inglês | MEDLINE | ID: mdl-32653763

RESUMO

Monitoring of tropane alkaloids is regulated in the European Union in cereal-based foods for infants and young children, tea and herbal infusions. The European Commission's Joint Research Centre (JRC) developed an improved LC-MS/MS analytical method using a pentafluorophenyl column, validated it and conducted two proficiency tests targeting these food categories. A subset of the data gathered from laboratories that used the JRC method was additionally exploited to derive interlaboratory performance characteristics. The method showed fit-for-purpose figures of merit. The LOQs for atropine and scopolamine were around 0.4 and 1.2 µg/kg in cereal products, and in tea and herbal infusions, respectively. Uncertainties varied from 15 to 25%. The reproducibility varied from 11 to 38% for scopolamine and from 17 to 44% for atropine at levels ranging from 0.18 to 18.8 and 1.2-54.0 µg/kg, respectively. Recoveries ranged from 71 to 96%. These performance parameters render the method a good candidate for standardisation.


Assuntos
Alcaloides/análise , Grão Comestível/química , Chá/química , Tropanos/análise , Alcaloides/química , Atropina/análise , Cromatografia Líquida de Alta Pressão , Humanos , Limite de Detecção , Reprodutibilidade dos Testes , Escopolamina/análise , Espectrometria de Massas em Tandem/métodos , Tropanos/química
7.
J Chromatogr A ; 1624: 461215, 2020 Aug 02.
Artigo em Inglês | MEDLINE | ID: mdl-32540065

RESUMO

A method for the preparation of an on-column ESI emitter used as the sheathless interface for coupling capillary electrophoresis (CE) with mass spectrometry (MS) was developed. The emitter was directly fabricated at the outlet end of the separation capillary which was etched with HF solution to a symmetrical tip. The tip was covered with a small piece of gold foil which was fixed by epoxy resin glue for electrical contact. Such a prepared ESI emitter can produce a stable ESI signal over the wide range of flow rate from 50 nL/min to 800 nL/min. The performance of the CE-MS with the sheathless interface was evaluated by using the separation of four alkaloids. It was found that the strong electroosmotic flow produced by the multiple polyelectrolyte coating on the capillary is necessary for maintaining a stable MS signal. Effect of the running buffer composition, concentration and the CE separation voltages on the ESI signal strength were investigated. The absolute detection limits for the alkaloids was determined as fmol level. Moreover, the CE-MS was applied for the analyses of trypsin digestion of cytochrome C and small molecular organic anions. The emitter performed very stable with a lifetime of at least 180 h.


Assuntos
Ouro/química , Dióxido de Silício/química , Espectrometria de Massas por Ionização por Electrospray/métodos , Alcaloides/análise , Eletroforese Capilar , Limite de Detecção , Polieletrólitos/química
8.
PLoS One ; 15(6): e0233516, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-32479498

RESUMO

The Balkans endemic species Alkanna primuliflora Griseb., A. stribrnyi Velen., and A. graeca Boiss. & Spruner have limited distribution in the Balkan Peninsula and a large variation in the morphological characteristics. The populations of the three Alkanna species in the Bulgarian flora are small and fragmented. There are no previous reports on the chemical profile or on the embryology of these species. The hypothesis was that the limited distribution of A. primuliflora, A. stribrnyi, and A. graeca was due to their reproductive capacity and genetic diversity. Furthermore, we hypothesized that the three species will contain pyrrolizidine alkaloids (PAs), as other species of the genus Alkanna (Boraginaceae), but they would have differential alkaloids composition. The population genetic structure and differentiation showed a clear distinction between species and revealed average levels of genetic diversity among the natural populations of the three Alkanna species. The embryological investigation observed stability of the processes in the male and female generative spheres and high viability of mature pollen and embryo of the three species. The normal formation of male and female gametophytes without deviations or degenerative processes, and observed levels of genetic diversity between Alkanna individuals are important in maintaining the size and resilience of the Alkanna populations. Eight alkaloids were identified by GC-MS in A. primuliflora and A. graeca and six alkaloids in A. stribrnyi. The main pyrrolizidine alkaloids (PAs) in all investigated species was triangularine. A. primuliflora and A. graeca showed similar chemical composition that comprised 9-angeloylretronecine, 7-tigloylretronecine, 9-tigloylretronecine, triangularicine, dihydroxytriangularine, dihydroxytriangularicine, whereas, in A. stribrnyi 9-tigloylretronecine, triangularicine and dihydroxytriangularicine were not found. This is the first report on the presence of PAs in A. primuliflora, A. stribrnyi and A. graeca. Besides, this is the first report on the embryology of these endemic species. The results contribute to the knowledge of the three endemic Alkanna species and will facilitate policy-making and defining new strategies for their conservation.


Assuntos
Boraginaceae/química , Boraginaceae/genética , Alcaloides/análise , Península Balcânica , Boraginaceae/metabolismo , Bulgária , Cromatografia Líquida de Alta Pressão/métodos , Cromatografia Gasosa-Espectrometria de Massas/métodos , Variação Genética/genética , Extratos Vegetais/química , Alcaloides de Pirrolizidina/química , Reprodução/fisiologia , Especificidade da Espécie
9.
Food Chem ; 328: 127117, 2020 Oct 30.
Artigo em Inglês | MEDLINE | ID: mdl-32474240

RESUMO

This study was aimed to reduce the concentrations of benzopyrene (BaP) and acrylamide (ACR) in roasted coffee beans by corona discharge plasma jet (CDPJ). The initial concentrations of BaP and ACR in roasted beans were decreased by 53.6% and 32.0%, respectively, following CDPJ (powered by 20 kV DC/1.5 A) treatment for 60 min. The levels of total solid, total acid, chlorogenic acid, caffeine, trigonelline, and pH were insignificantly changed upon CDPJ treatment compared to controls. However, the concentration of total phenolic content and Agtron color values were altered significantly. The treatment of beans did not alter descriptive sensory properties of the corresponding coffee brews, except aroma and aftertaste characteristics. As the treatment time increased from 15 to 60 min, scores for aroma profiles in PCA plot were shifted from right to left, although overlapping was observed between 15- and 30-min-treated samples. Additionally, none of the treated samples were discriminated from the control by electronic tongue.


Assuntos
Acrilamida/química , Benzopirenos/química , Café/química , Alcaloides/análise , Fenômenos Bioquímicos , Cafeína/análise , Ácido Clorogênico/análise , Culinária , Nariz Eletrônico , Temperatura Alta
10.
J Anal Toxicol ; 44(7): 679-687, 2020 Oct 12.
Artigo em Inglês | MEDLINE | ID: mdl-32591789

RESUMO

Synthetic cathinones, commonly referred to as "bath salts," are powerful amphetamine-like psychostimulants, and new derivatives are constantly appearing in the illicit market to evade judicial consequences. To keep up with these new stimulant drugs, a low-sample-size liquid chromatography-tandem mass spectrometry method was validated to quantify 30 synthetic cathinones in postmortem blood including N-ethylpentylone and eutylone. Mixed mode cation exchange solid-phase extraction using 0.25 mL postmortem blood was performed followed by detection using a triple quadrupole mass spectrometer operating electrospray ionization in positive mode. The reversed-phase chromatographic separation was achieved in 16 min, resolving all isobaric compounds. The linear range of the calibration curve was 1-500 ng/mL (R  2 > 0.99) for all compounds. Limit of quantification (LOQ) and limit of detection were determined to be at 1 ng/mL. Both imprecision and bias were evaluated and had met all allowed criteria (CV and bias <20%). No matrix effect was observed with values ranging from -5.1 to 13.3% (CV 11.4-17.5%, n = 10). Extraction efficiency (84.9-91.5%) and process efficiency (86.1-102.6%) were satisfactory, except for 4-chloroethcathinone which was 63 and 64.9%, respectively. No carryover after the upper LOQ was detected. Neither endogenous nor exogenous interferences were observed. Both dilution integrity and stability (24 h) yielded acceptable results. This method was applied to 18 postmortem cases received between 2015 and 2019. Eight different synthetic cathinones were detected in selected postmortem cases within the past 5 years, showing a wide range of concentrations from 1.4 to >500 ng/mL. While ethylone and methylone were detected in 2015, cases between 2016 and 2017 were predominantly butylone, dibutylone, pentylone and N-ethylpentylone which had also exhibited a significant increase in 2018. To our knowledge, this method is the most comprehensive methodology for the determination of up-to-date synthetic cathinones currently available in whole blood.


Assuntos
Alcaloides/análise , Toxicologia Forense , Detecção do Abuso de Substâncias , Cromatografia Líquida , Humanos , Limite de Detecção , Espectrometria de Massas em Tandem
11.
Bol. latinoam. Caribe plantas med. aromát ; 19(3): 289-299, mayo 2020. ilus, tab
Artigo em Inglês | LILACS | ID: biblio-1116296

RESUMO

Piper kadsura (Choisy) Ohwi which belongs to the family Piperaceae, is a well-known medicinal plant possessing high medicinal and various therapeutic properties. It is widely used in traditional Chinese medicine for the treatment of asthma and rheumatic arthritis. Numerous studies on this species have also corroborated the significant anti-inflammatory potential of its extracts and secondary metabolites. The main chemical constituents which have been isolated and identified from P. kadsura are lignans and neolignans, which possess anti-inflammatory activities. The present article aims to provide a review of the studies done on the phytochemistry and antiinflammatory activities of P. kadsura. The scientific journals for this brief literature review were from electronic sources, such as Science Direct, PubMed, Google Scholar, Scopus, and Web of Science. This review is expected to draw the attention of the medical professionals and the general public towards P. kadsura and to open the door for detailed research in the future.


Piper kadsura (Choisy) Ohwi, perteneciente a la familia Piperaceae, es una planta medicinal conocida que posee importantes propiedades medicinales y diversas propiedades terapéuticas. Es ampliamente utilizada en la medicina tradicional china para el tratamiento del asma y la artritis reumática. Numerosos estudios sobre esta especie también han corroborado el destacado potencial antiinflamatorio de sus extractos y metabolitos secundarios. Los principales componentes químicos que se han aislado e identificado de P. kadsura son los lignanos y los neolignanos, que poseen actividades antiinflamatorias. El presente artículo tiene como objetivo proporcionar una revisión de los estudios realizados sobre las actividades fitoquímicas y antiinflamatorias de P. kadsura. Las revistas científicas para esta breve revisión de literatura fueron de fuentes electrónicas, como Science Direct, PubMed, Google Scholar, Scopus y Web of Science. Se espera que esta revisión atraiga la atención de los profesionales médicos y el público en general respecto de P. kadsura y abra la puerta a una investigación detallada en el futuro.


Assuntos
Piper/química , Anti-Inflamatórios/química , Plantas Medicinais , Óleos Voláteis/química , Lignanas/análise , Piperaceae/química , Kadsura , Alcaloides/análise , Compostos Fitoquímicos/análise , Medicina Tradicional Chinesa , Anti-Inflamatórios/farmacologia
12.
Bol. latinoam. Caribe plantas med. aromát ; 19(3): 247-288, mayo 2020. tab
Artigo em Inglês | LILACS | ID: biblio-1116290

RESUMO

Selaginella is the only genus from Selaginellaceae, and it is considered a key factor in studying evolution. The family managed to survive the many biotic and abiotic pressures during the last 400 million years. The purpose of this review is to provide an up-to-date overview of Selaginella in order to recognize their potential and evaluate future research opportunities. Carbohydrates, pigments, steroids, phenolic derivatives, mainly flavonoids, and alkaloids are the main natural products in Selaginella. A wide spectrum of in vitro and in vivo pharmacological activities, some of them pointed out by folk medicine, has been reported. Future studies should afford valuable new data on better explore the biological potential of the flavonoid amentoflavone and their derivatives as chemical bioactive entities; develop studies about toxicity and, finally, concentrate efforts on elucidate mechanisms of action for biological properties already reported.


Selaginella es el único género de Selaginellaceae, y se considera un factor clave en el estudio de la evolución. La familia logró sobrevivir a las muchas presiones bióticas y abióticas durante los últimos 400 millones de años. El propósito de esta revisión es proporcionar un resumen actualizado de Selaginella para reconocer su potencial y evaluar futuras oportunidades de investigación. Los hidratos de carbono, pigmentos, esteroides, derivados fenólicos, principalmente flavonoides, y alcaloides son los principales productos naturales en Selaginella. Se ha informado un amplio espectro de actividades farmacológicas in vitro e in vivo, algunas de ellas señaladas por la medicina popular. Los estudios futuros deberían proporcionar datos nuevos y valiosos para explorar mejor el potencial biológico de la amentoflavona flavonoide y sus derivados como entidades bioactivas químicas; desarrollar estudios sobre la toxicidad y, finalmente, concentrar los esfuerzos en dilucidar los mecanismos de acción para las propiedades biológicas ya informadas.


Assuntos
Extratos Vegetais/farmacologia , Extratos Vegetais/química , Selaginellaceae/química , Flavonoides/análise , Alcaloides/análise , Medicina Tradicional
13.
J Chromatogr A ; 1621: 461044, 2020 Jun 21.
Artigo em Inglês | MEDLINE | ID: mdl-32273090

RESUMO

The presented paper is the first to show thin layer chromatography (TLC) analysis based on eutectic mobile phases (Deep Eutectic Solvents - DES). During the experiment 25 eutectic mixtures were investigated for their chromatographic properties. Most of them belong to the natural deep eutectic solvents (NADES) group. Also, new eutectic liquids based on phenolics and terpenes, not previously employed in analytical practice, were tested. The eutectic liquids were investigated as pure or diluted with solvents used in chromatographic routine: methanol, water, acetone, chloroform or diethyl ether. The analyses were carried out using classic and high performance silica gel plates. The working solution was a mixture of five alkaloids found in genus Chelidonium, namely sanguinarine, coptisine, chelerythrine, chelidonine, and berberine, with UV light detection of 366 nm. This report proves that eutectic TLC is possible and that the eutectic interactions play a crucial role in the separation process. In most of the tested modifications at least partial separation was achieved. The most successful mobile phase, which enabled separation of all the tested alkaloids, was the equimolar mixture of menthol and phenol with a 35% addition of methanol. The system was also effective in separating alkaloids in the real Chelidonium maius extract sample.


Assuntos
Cromatografia em Camada Delgada/métodos , Alcaloides/análise , Chelidonium/química , Fenóis/química , Extratos Vegetais/química , Solventes/química , Terpenos/química
14.
Zhongguo Zhong Yao Za Zhi ; 45(5): 1082-1089, 2020 Mar.
Artigo em Chinês | MEDLINE | ID: mdl-32237450

RESUMO

Some Chinese herbal medicine needs to be processed before it can be used as medicine, especially toxic Chinese medicine. Highly toxic Aconti Kusnezoffii Radix(Caowu in Chinese) is widely used in traditional Chinese medicine and Mongolian medicine. In traditional Chinese medicine, Caowu is usually processed by boiling with water(CW) until no white part inside and being tasted without tongue-numbing. In Mongolian medicine, it is usually soaked in Chebulae Fructus(Hezi in Chinese) decoction for several days(CH). Both methods could reduce toxicity according to reports. The biggest difference between CW and CH is that CW needs to be heated for 4-6 h, while CH needs Hezi as processing adjuvants. To explore the toxicity reduction mechanism of CW and CH, we studied the contents of various compounds in Caowu processed by two methods by UPLC-Orbitrap-MS. The results indicated that CW had 14 new ingredients, such as 14-O-anisoylneoline and dehydro-mesaconitine, while N-demethyl-mesaconitine and aconitine disappeared. At the same time, it could significantly decrease the content of diester diterpenoid alkaloids and increase the contents of monoester diterpenoid alkaloids and amine-diterpenoid alkaloids. CH had 9 new ingredients from Hezi, like gallic acid, chebulic acid and shikimic acid. Neither the kinds nor the contents of compositions from Caowu in CH changed little. This suggested that the processing mechanism of CW reduced highly toxic components(diester diterpenoid alkaloids) and increased the content of lowly toxic components(monoester diterpenoid alkaloids and amine-diterpenoid alkaloids). Attenuated principle of CH may be related to the components of Hezi. In this experiment, the conclusion shows that the chemical constituents of CW and CH are essentially different, and the two methods have different toxicity reduction principles.


Assuntos
Aconitum/química , Alcaloides/análise , Medicamentos de Ervas Chinesas/análise , Aconitina , Química Farmacêutica/métodos , Cromatografia Líquida de Alta Pressão , Espectrometria de Massas , Medicina Tradicional Chinesa
15.
Zhongguo Zhong Yao Za Zhi ; 45(6): 1393-1398, 2020 Mar.
Artigo em Chinês | MEDLINE | ID: mdl-32281353

RESUMO

An UPLC method was established for the direct determination of six major bioactive isosteroidal alkaloids, namely peimisine, imperialine, sipeimine-3-D-glucoside, verticinone, verticine and hupehenine from the bulbus of Fritillaria(Beimu), a commonly used antitussive traditional Chinese medicinal(TCM) herb. An Acquity UPLC~(TM) CSH C_(18) column(2.1 mm×100 mm, 1.7 µm) was used for all analysis. The investigated six compounds were all separated with gradient mobile phase consisting of 0.02% diethylamine-water-methanol at a flow rate of 0.3 mL·min~(-1). The temperature of sample manager was set at 20 ℃. Drift tube temperature was 45 ℃, and spray parameter was 40% with injection volume of 1 µL. Then, the further quality assessment of Beimu was carried out by cluster analysis(CA) and principal component analysis(PCA). The investigated all had good linearity(r≥0.998 9) over the tested ranges. The method is simple, accurate and reproducible, and can be used for determining the content of six major bioactive isosteroidal alkaloids.


Assuntos
Alcaloides/análise , Medicamentos de Ervas Chinesas/química , Fritillaria/química , Alcaloides/isolamento & purificação , Cromatografia Líquida de Alta Pressão , Compostos Fitoquímicos/análise , Compostos Fitoquímicos/isolamento & purificação , Raízes de Plantas/química
16.
J Chromatogr A ; 1621: 461045, 2020 Jun 21.
Artigo em Inglês | MEDLINE | ID: mdl-32201036

RESUMO

New zwitterionic (ZIC) stationary phases (SPs) are synthesized with the click and conventional bonding of tyrosine to silica gel. Infrared spectra and elemental analysis demonstrate the successful click and conventional bonding of this ZIC group on silica particles by the surface coverage including 2.36 and 0.75 µm m-2, respectively. Given the above-mentioned explanation, the present study evaluated the retention mechanism and chromatographic manners of polar compounds on these new materials under hydrophilic interaction liquid chromatography (HILIC) conditions. Based on the results, the Click-Tyrosine Stationary Phase provided good HILIC characteristics when it was applied to separate phenolic compounds, amino acids, alkaloids, and nucleobases compared to bare silica gel SP and even conventional tyrosine SPs. Further, this new Click-Tyrosine-SP represented appropriate HILIC features and column efficiency (the theoretical plate number was up to 50,000 plates m-1 for thebaine). Furthermore, the study investigated the effect of solute polarity (the number of the hydroxyl group of phenolic compounds) and hydrophobicity (the number of the side chain of aliphatic amino acids) on retention behaviors. Finally, some important factors were studied as the potential variables for guiding the retention behavior of the polar compound in HILIC condition including solvent composition, salt concentration, and the buffer pH of the mobile phase.


Assuntos
Cromatografia Líquida/métodos , Tirosina/química , Alcaloides/análise , Alcaloides/isolamento & purificação , Aminoácidos/análise , Aminoácidos/isolamento & purificação , Química Click , Interações Hidrofóbicas e Hidrofílicas , Fenóis/análise , Fenóis/isolamento & purificação , Sílica Gel/química
17.
PLoS One ; 15(3): e0229589, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-32155163

RESUMO

Securinega suffruticosa (Pall.) Rehd is an excellent natural secondary shrub in the Shell Islands of Yellow River Delta. The roots of S. suffruticosa have high medicinal value and are used to treat diseases, such as neurasthenia and infant malnutrition. Any organism that is isolated from this species is of immense interest due to its potential novel bioactive compounds. In this research, the distribution and diversity of culturable endophytic fungi in S. suffruticosa were studied, and the endophytic fungi with antimicrobial activity were screened. A total of 420 endophytic fungi isolates were obtained from the S. suffruticosa grown in Shell Islands, from which 20 genera and 35 species were identified through morphological and internal transcribed spacer (ITS) sequence analyses. Chaetomium, Fusarium, Cladosporium, and Ceratobasidium were the dominant genera. The high species richness S (42), Margalef index D' (5.6289), Shannon-Wiener index H' (3.1000), Simpson diversity index Ds (0.9459), PIE index (0.8670), and evenness Pielou index J (0.8719) and a low dominant index λ (0.0541) indicated the high diversity of endophytic fungi in S. suffruticosa, the various species of endophytic fungi with obvious tissue specificity. The inhibition percentages of the 12 species of such endophytic fungi against Colletotrichum siamense were 3.6%-26.3%. C. globosum, Fusarium sp.3, and C. ramotenellum had a high antibacterial activity against Enterococcus faecalis, Escherichia coli, Pseudomonas aeruginosa, and Staphylococcus aureus. The Minimum Inhibitory Concentration (MIC) and the Minimum Bactericidal Concentration (MBC) were between 0.5 mg/mL and 2 mg/mL. Alkaloid content detection indicated that endophytic fungi had a high alkaloid content, whereas the alkaloid contents of C. globosum and Fusarium sp.3 reached 0.231% and 0.170%, respectively. Members belonging to the endophytic fungal community in the S. suffruticosa of Shell Islands that may be used as antagonists and antibacterial agents for future biotechnology applications were identified for the first time.


Assuntos
Endófitos/genética , Endófitos/fisiologia , Fungos/genética , Fungos/fisiologia , Plantas Medicinais/microbiologia , Securinega/microbiologia , Alcaloides/análise , Anti-Infecciosos/análise , Biodiversidade , China , DNA Fúngico/genética , DNA Fúngico/isolamento & purificação , Endófitos/isolamento & purificação , Fungos/classificação , Testes de Sensibilidade Microbiana , Filogenia , Rios
18.
Artigo em Inglês | MEDLINE | ID: mdl-32169797

RESUMO

Daodi medicinal material (DMM), which is traditional Chinese herbal medicine that has been used for long periods and have gained credibility in clinical practice, is part of the Chinese culture. However, Zhongning Goji berries (ZNG), a DMM, are illegally adulterated in the market by adding non Zhongning goji berries (NZNG). Consequently, the development of biomarker(s) is necessary for proper identification of ZNG and NZNG. In this study, a nontargeted metabolomics approach based on ultra high-performance liquid chromatography coupled with quadrupole time-of-flight mass spectrometry (UHPLC-Q-TOF-MS) was used to find the differential composition between ZNG and NZNG. Using a combination of single-factor and multivariate statistical analyses, seven compounds with significant differences were discovered and identified, one of which was an unreported compound (a glycoside of pyrrolidine alkaloid). These compounds could be used as single biomarkers for receiver operating characteristic (ROC) analysis. In particular, the binary logistic regression result showed that two sets of combinative biomarkers to distinguish ZNG from NZNG with good sensitivity and specificity. Moreover, there was a significant positive correlation between the two combinative biomarkers and the glycoside of pyrrolidine alkaloid. The results of this study provide new ideas on the developments of ZNG identification, authenticity control and against adulteration in the Chinese circulation market.


Assuntos
Biomarcadores/análise , Medicamentos de Ervas Chinesas/química , Lycium/química , Alcaloides/análise , Cromatografia Líquida de Alta Pressão , Glicosídeos/análise , Análise Multivariada , Análise de Componente Principal , Controle de Qualidade , Curva ROC , Espectrometria de Massas em Tandem
19.
J Chromatogr A ; 1620: 461036, 2020 Jun 07.
Artigo em Inglês | MEDLINE | ID: mdl-32201039

RESUMO

Leaves, flowers, fruits and stems (44 sample groups) were collected from mature Camptotheca acuminate during 2017.3-2018.3 and classified by ultra-high performance liquid chromatography coupled with quadrupole-time of flight-mass spectrometry based metabolomics. One hundred metabolites including forty-seven alkaloids, fifteen terpenes, thirty-two polyphenols and six other metabolites were rapidly identified through the in-house database alignment at first glance. Thirty-three alkaloids classified into five groups including camptothecin group (CG1-13), pumiloside group (PG1-5), strictosidinic acid group (SG1-3), vincosamide group (VG1-7), and a new hybrid group, vincosamide-camptothecin group (VC1-5) were mined and further characterized by MS/MS analyses. The identification of two untapped biosynthetic precursors, 2-hydroxypumiloside (PG2) and 16­hydroxy­15, 16-dihydrocamptothecoside (CG3), along with sixteen new alkaloids enables us for a better understanding of camptothecin biogenetic reasoning. The underlying enzymes involved in camptothecin biosynthesis were also proposed according to the guiding metabolic map, thus purposefully mining of enzymes involved in the downstream biosynthetic pathway of camptothecin could be initiated with the help of this map.


Assuntos
Alcaloides/análise , Vias Biossintéticas , Camptotheca/química , Cromatografia Líquida de Alta Pressão/métodos , Espectrometria de Massas em Tandem/métodos , Camptotecina/análogos & derivados , Camptotecina/análise , Camptotecina/química , Camptotecina/metabolismo , Carbolinas/análise , Carbolinas/química , Bases de Dados como Assunto , Análise Discriminante , Glicosídeos/análise , Glicosídeos/química , Alcaloides Indólicos/análise , Alcaloides Indólicos/química , Análise dos Mínimos Quadrados , Redes e Vias Metabólicas , Metaboloma , Metabolômica , Análise Multivariada , Análise de Componente Principal
20.
J Anal Toxicol ; 44(6): 601-609, 2020 Jul 31.
Artigo em Inglês | MEDLINE | ID: mdl-32103256

RESUMO

Ayahuasca, a hallucinogenic beverage used in religious rituals in South America, has become a global phenomenon. Its main active components are the ß-carbolines alkaloids, harmine (HRM) and harmaline (HRL), as well as the potent hallucinogen N,N-dimethyltryptamine (DMT). Despite its rising consumption, information regarding possible clinical applications and toxicological effects of ayahuasca is still limited. This study presents the first investigation of the use of sweat for the determination of DMT, HRM and HRL in ayahuasca users during a religious ritual. Sweat is an alternative matrix with advantages over many conventional biological samples, mainly because the collection procedure is non-invasive, easy and simple and samples can be collected without disturbing the religious ritual. In the study, solid-phase extraction was performed under basic conditions. Linearity was observed ranging from 20 to 1500 ng/patch with coefficients of determination (R2) higher than 0.99 for all analytes. The results indicated high selectivity for all investigated analytes, with extraction efficiency exceeding 70%, accuracy ranging from 87.5 to 102.4%, intra-assay precision of 1.85-9.44% and inter-assay precision between 3.34 and 9.85%. The limits of detection were 15 ng/patch for HRM and HRL and 10 ng/patch for DMT. The sweat proved to be a viable option to monitor ayahuasca use.


Assuntos
Alcaloides/análise , Banisteriopsis , Carbolinas/análise , Alucinógenos/análise , Detecção do Abuso de Substâncias/métodos , Suor/química , Triptaminas/análise , Cromatografia Gasosa-Espectrometria de Massas , Humanos , Religião
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