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1.
Phytochemistry ; 178: 112463, 2020 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-32888669

RESUMO

Ten undescribed alkaloids, named integerrines A-J, including one racemic heterodimer of carbazole and indole, two racemic, two scalemic, and one enantiomerically enriched biscarbazoles, two aldoximes, and one racemic pyrrolone, were isolated from the dried leaves and stems of Micromelum integerrimum. The racemic or scalemic compounds were resolved using chiral-phase HPLC and their configurations were determined by comparison of experimental and calculated ECD data. Four compounds exhibited moderate to weak cytotoxicities against HepG2, HTC-116, HeLa, and PANC-1 cell lines, with IC50 values of 14.1-67.5 µM.


Assuntos
Alcaloides , Antineoplásicos , Rutaceae , Linhagem Celular Tumoral , Humanos , Estrutura Molecular , Folhas de Planta
2.
Phytochemistry ; 178: 112459, 2020 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-32888673

RESUMO

Nine unprecedented diterpenoid alkaloid, including a diterpenoid alkaloid featuring a diterpenoid moiety, anthoroidine A; one bisditerpenoid alkaloid joined with a carbon-carbon single bond, anthoroidine B; three racemulosine-type C20-diterpenoid alkaloids, anthoroidines C-E; one hetidine-type C20-diterpenoid alkaloid, anthoroidine F; and three hetisine-type C20-diterpenoid alkaloids, anthoroidines G-I, together with ten known diterpenoid alkaloids were isolated from Aconitum anthoroideum DC. Their structures were established via detailed spectroscopic analyses. Most of the isolated compounds along with five known diterpenoid alkaloids obtained in a previous study were screened for neuroprotective activities and acetylcholinesterase inhibitory effects. Nominine showed potent protective activity against MPP+-induced apoptosis in SH-SY5Y cells, with a rescue rate of 34.4% (50 µM). Rotundifosine F showed a significant inhibitory activity against AChE (IC50 = 0.3 µM). The structure-activity relationship of these alkaloids is also briefly discussed.


Assuntos
Aconitum , Alcaloides , Diterpenos , Acetilcolinesterase , Apoptose , Estrutura Molecular , Raízes de Plantas
3.
Nat Commun ; 11(1): 3337, 2020 07 03.
Artigo em Inglês | MEDLINE | ID: mdl-32620756

RESUMO

The tetrahydroisoquinoline (THIQ) moiety is a privileged substructure of many bioactive natural products and semi-synthetic analogs. Plants manufacture more than 3,000 THIQ alkaloids, including the opioids morphine and codeine. While microbial species have been engineered to synthesize a few compounds from the benzylisoquinoline alkaloid (BIA) family of THIQs, low product titers impede industrial viability and limit access to the full chemical space. Here we report a yeast THIQ platform by increasing production of the central BIA intermediate (S)-reticuline to 4.6 g L-1, a 57,000-fold improvement over our first-generation strain. We show that gains in BIA output coincide with the formation of several substituted THIQs derived from amino acid catabolism. We use these insights to repurpose the Ehrlich pathway and synthesize an array of THIQ structures. This work provides a blueprint for building diverse alkaloid scaffolds and enables the targeted overproduction of thousands of THIQ products, including natural and semi-synthetic opioids.


Assuntos
Alcaloides/biossíntese , Benzilisoquinolinas/metabolismo , Saccharomyces cerevisiae/metabolismo , Tetra-Hidroisoquinolinas/metabolismo , Alcaloides/química , Analgésicos Opioides/química , Analgésicos Opioides/metabolismo , Benzilisoquinolinas/química , Produtos Biológicos/química , Produtos Biológicos/metabolismo , Vias Biossintéticas/genética , Engenharia Genética , Modelos Químicos , Estrutura Molecular , Saccharomyces cerevisiae/genética , Tetra-Hidroisoquinolinas/química
4.
Nat Commun ; 11(1): 3538, 2020 07 15.
Artigo em Inglês | MEDLINE | ID: mdl-32669587

RESUMO

Ever since Hirata's report of yuzurimine in 1966, nearly fifty yuzurimine-type alkaloids have been isolated, which formed the largest subfamily of the Daphniphyllum alkaloids. Despite extensive synthetic studies towards this synthetically challenging and biologically intriguing family, no total synthesis of any yuzurimine-type alkaloids has been achieved to date. Here, the first enantioselective total synthesis of (+)-caldaphnidine J, a highly complex yuzurimine-type Daphniphyllum alkaloid, is described. Key transformations of this approach include a highly regioselective Pd-catalyzed hydroformylation, a samarium(II)-mediated pinacol coupling, and a one-pot Swern oxidation/ketene dithioacetal Prins reaction. Our approach paves the way for the synthesis of other yuzurimine-type alkaloids and related natural products.


Assuntos
Alcaloides/síntese química , Daphniphyllum/química , Produtos Biológicos , Catálise , Desenho de Fármacos , Etilenos/química , Cetonas/química , Espectroscopia de Ressonância Magnética , Modelos Químicos , Estrutura Molecular , Oxirredução , Oxigênio/química , Samário/química , Estereoisomerismo
5.
J Chromatogr A ; 1625: 461286, 2020 Aug 16.
Artigo em Inglês | MEDLINE | ID: mdl-32709336

RESUMO

In the past two decades, supercritical fluid chromatography has evolved from a niche application to a comprehensive technology and a fully-fledged alternative to conventional high-performance liquid chromatography. In this study, we have focused on chiral separation of synthetic cathinones in gradient supercritical fluid chromatography coupled to mass spectrometry using an inverse gradient of a make-up solvent. Synthetic cathinones possess an amphetamine-like effect and, therefore, are frequently being offered on the Internet as a replacement for illicit drugs. Cathinones are chiral compounds, however, they are usually marketed and used as racemic mixtures. Since the effect of individual enantiomers can significantly vary, there is a need for the development of enantioseparation methods enabling to study the biological effects of individual enantiomers. Since cathinones are basic molecules, they are easily protonated (positively charged) under weakly acidic mobile phase conditions, which is a typical feature of supercritical mobile phases with an alcohol as an organic modifier. The positively charged species represent ideal analytes for ion exchangers, such as chiral zwitterion ion exchangers Chiralpak ZWIX (+) and Chiralpak ZWIX (-), which possess a positively and negatively charged unit in the molecular structure of the selectors. The presence of the positive charge in the selector's structure, functioning as a counter-ion for the positively charged analytes, significantly reduces the required amount of a buffer, which is plausible for hyphenation of such a separation system with mass spectrometry. For mass spectrometry hyphenated to supercritical fluid chromatography, the use of a make-up solvent is required to avoid analyte precipitation when using a low concentration of an organic co-solvent (modifier) in the super-/subcritical mobile phase. Hereby, we introduce a unique approach, which is based on the gradient introduction of the make-up to the post-column effluent. Using this approach, it is possible to keep constant the overall amount of the organic solvent (modifier and make-up) introduced into the mass spectrometer when using a gradient of the organic modifier. We show that the developed gradient elution method facilitates the chiral separation of all employed analytes, while the mobile-phase gradient compensation by the inverse make-up gradient enables their detection with high signal intensities.


Assuntos
Alcaloides/química , Alcaloides/isolamento & purificação , Cromatografia com Fluido Supercrítico/métodos , Espectrometria de Massas/métodos , Reologia , Solventes/química , Alcaloides/síntese química , Cromatografia Líquida de Alta Pressão , Pressão , Estereoisomerismo , Temperatura
6.
Rev Bras Parasitol Vet ; 29(2): e019819, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-32609242

RESUMO

We investigated the in vitro acaricide activity of the methanolic extract (ME) and alkaloid-rich fraction (AF) of Prosopis juliflora on Rhipicephalus microplus and correlated this effect with acetylcholinesterase (AChE) inhibition. The acaricide activity was evaluated using adult and larval immersion tests. Also, we studied the possible interaction mechanism of the major alkaloids present in this fraction via molecular docking at the active site of R. microplus AChE1 (RmAChE1). Higher reproductive inhibitory activity of the AF was recorded, with effective concentration (EC50) four times lower than that of the ME (31.6 versus 121 mg/mL). The AF caused mortality of tick larvae, with lethal concentration 50% (LC50) of 13.8 mg/mL. Both ME and AF were seen to have anticholinesterase activity on AChE of R. microplus larvae, while AF was more active with half-maximal inhibitory concentration (IC50) of 0.041 mg/mL. The LC-MS/MS analyses on the AF led to identification of three alkaloids: prosopine (1), juliprosinine (2) and juliprosopine (3). The molecular docking studies revealed that these alkaloids had interactions at the active site of the RmAChE1, mainly relating to hydrogen bonds and cation-pi interactions. We concluded that the alkaloids of P. juliflora showed acaricide activity on R. microplus and acted through an anticholinesterase mechanism.


Assuntos
Alcaloides , Colinesterases , Extratos Vegetais , Prosopis , Rhipicephalus , Acaricidas/farmacologia , Alcaloides/farmacologia , Animais , Colinesterases/metabolismo , Cromatografia Líquida , Ativação Enzimática/efeitos dos fármacos , Larva , Simulação de Acoplamento Molecular , Extratos Vegetais/farmacologia , Prosopis/química , Rhipicephalus/efeitos dos fármacos , Rhipicephalus/enzimologia , Espectrometria de Massas em Tandem
7.
Zhongguo Zhong Yao Za Zhi ; 45(10): 2221-2231, 2020 May.
Artigo em Chinês | MEDLINE | ID: covidwho-438384

RESUMO

In this paper, we analyzed medical records of 40 patients with coronavirus disease 2019(COVID-19), in order to explore the clinical efficacy of Matrine and Sodium Chloride Injection in the treatment of COVID-19. The investigation was based on the results of a previous animal test, which was aimed to investigate and confirme the clinical efficacy of Matrine and Sodium Chloride Injection in the treatment of COVID-19. The animal test demonstrated that Matrine and Sodium Chloride Injection has a significant therapeutic effect on the human coronavirus pneumonia for the model mice. The lung inhibition index reached up to 86.86%. The evaluation was conducted on 40 confirmed cases of COVID-19 treated at Jingzhou Hospital of Infectious Disease(Chest Hospital) of Hubei Pro-vince from January 30~(th) to March 21~(th), 2020. In these cases, patients were treated with other integrated Chinese and Western medicines regimens in the recommended Matrine and Sodium Chloride Injection diagnosis and treatment regimen. The clinical manifestations, laboratory data, nucleic acid clearance time, and imaging data were compared and analyzed before and after treatment. After administration with Matrine and Sodium Chloride Injection, the clinical symptoms of 40 cases were alleviated markedly, and their blood analysis and biochemical indexes returned to normal. The lung CT showed more than 50% of lesion absorption rate, and the viral nucleic acid test showed the average clearance time of patients was 16.6 days, and the average length of hospital stay was 25.9 days. After administration with Matrine and Sodium Chloride Injection, the symptoms of cough and fatigue were alleviated significantly, and the appetite was significantly improved compared with before, especially for patients with gastrointestinal symptoms. Additionally, laboratory indicators, especially absolute value and ratio of lymphocytes and CRP were significantly alleviated. According to the chest CT for short-term review, the absorption of lung lesions was faster than before, especially for grid-like and fibrotic lesions. Compared with antiviral drugs, such as Abidol and Kriging, the nucleic acid clearance time was significantly shorter than the cases treated with Matrine and Sodium Chloride Injection. The clinical effective rate of 40 cases was 100.0%. We believed that Matrine and Sodium Chloride Injection have a good clinical effect in the treatment of COVID-19, and suggested increasing the clinical application and further conducting large-sample-size cli-nical verification.


Assuntos
Betacoronavirus , Infecções por Coronavirus , Pandemias , Pneumonia Viral , Alcaloides , Animais , Modelos Animais de Doenças , Camundongos , Quinolizinas , Cloreto de Sódio , Resultado do Tratamento
8.
Plant Mol Biol ; 103(6): 705-718, 2020 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-32577984

RESUMO

Fritillariae Bulbus are the most commonly used antitussive and edible herbs in China. Based on UPLC-QTOF-MS and UPLC-QQQ-MS, the validated MRM-based non-targeted quantitative method was applied to determinate the contents of 48 Fritillaria alkaloids (FAs) in three Fritillaria species (F. thunbergii Miq., F. unibracteata and F. ussuriensis). The RNA-Seq results showed that gene transcript levels have different expression patterns in three Fritillaria species. Based on transcriptome data, the full-length cDNA sequences of squalene epoxidase gene were cloned and characterized. Natural evolution of squalene epoxidase genes resulted in four mutations (C236R, M489L, G510A and K517R) in three Fritillaria species. Molecular docking analysis showed that the 236 residue is located inside the pocket and the binding center while other three residues are located on the surface of the protein. Functional verification indicated the mutations of SQE (C236R) could effectively increase the activity of SQE and obtain higher yield of 2,3-oxidosqualene in recombinant yeast. And the mutations of SQE (M489L and G510A), which increased the hydrophobicity of the protein surface, could also enhance the activity of SQE. This study provides major insights into the metabolites differentiation of FAs biosynthesis, and a firm foundation for the quality control and metabolic engineering of Fritillariae bulbus.


Assuntos
Fritillaria/enzimologia , Esqualeno Mono-Oxigenase/metabolismo , Alcaloides/metabolismo , Cromatografia Líquida de Alta Pressão , DNA Complementar/genética , Simulação de Acoplamento Molecular , Mutação/genética , Filogenia , Alinhamento de Sequência , Esqualeno Mono-Oxigenase/genética
9.
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
10.
Zhongguo Zhong Yao Za Zhi ; 45(10): 2221-2231, 2020 May.
Artigo em Chinês | MEDLINE | ID: mdl-32495574

RESUMO

In this paper, we analyzed medical records of 40 patients with coronavirus disease 2019(COVID-19), in order to explore the clinical efficacy of Matrine and Sodium Chloride Injection in the treatment of COVID-19. The investigation was based on the results of a previous animal test, which was aimed to investigate and confirme the clinical efficacy of Matrine and Sodium Chloride Injection in the treatment of COVID-19. The animal test demonstrated that Matrine and Sodium Chloride Injection has a significant therapeutic effect on the human coronavirus pneumonia for the model mice. The lung inhibition index reached up to 86.86%. The evaluation was conducted on 40 confirmed cases of COVID-19 treated at Jingzhou Hospital of Infectious Disease(Chest Hospital) of Hubei Pro-vince from January 30~(th) to March 21~(th), 2020. In these cases, patients were treated with other integrated Chinese and Western medicines regimens in the recommended Matrine and Sodium Chloride Injection diagnosis and treatment regimen. The clinical manifestations, laboratory data, nucleic acid clearance time, and imaging data were compared and analyzed before and after treatment. After administration with Matrine and Sodium Chloride Injection, the clinical symptoms of 40 cases were alleviated markedly, and their blood analysis and biochemical indexes returned to normal. The lung CT showed more than 50% of lesion absorption rate, and the viral nucleic acid test showed the average clearance time of patients was 16.6 days, and the average length of hospital stay was 25.9 days. After administration with Matrine and Sodium Chloride Injection, the symptoms of cough and fatigue were alleviated significantly, and the appetite was significantly improved compared with before, especially for patients with gastrointestinal symptoms. Additionally, laboratory indicators, especially absolute value and ratio of lymphocytes and CRP were significantly alleviated. According to the chest CT for short-term review, the absorption of lung lesions was faster than before, especially for grid-like and fibrotic lesions. Compared with antiviral drugs, such as Abidol and Kriging, the nucleic acid clearance time was significantly shorter than the cases treated with Matrine and Sodium Chloride Injection. The clinical effective rate of 40 cases was 100.0%. We believed that Matrine and Sodium Chloride Injection have a good clinical effect in the treatment of COVID-19, and suggested increasing the clinical application and further conducting large-sample-size cli-nical verification.


Assuntos
Betacoronavirus , Infecções por Coronavirus , Pandemias , Pneumonia Viral , Alcaloides , Animais , Modelos Animais de Doenças , Camundongos , Quinolizinas , Cloreto de Sódio , Resultado do Tratamento
11.
Planta Med ; 86(11): 760-766, 2020 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-32512615

RESUMO

Higenamine is a natural benzyltetrahydroisoquinoline alkaloid produced by various plants. In the World Anti-Doping Agency report of 2020, higenamine is classified as a class S3 (selective and nonselective ß2-agonist) prohibited substance. To minimize the problems resulting from the misuse of higenamine-containing products as well as from the abuse of doping agents in sport, numerous higenamine-detection methods have been investigated. In the present study, a monoclonal antibody against the (S)-enantiomer of higenamine was successfully produced and applied in the indirect competitive ELISA to detect the content of (S)-higenamine in plant samples and related products. By immunizing BALB/c mice with higenamine-BSA, the aforementioned monoclonal antibody was produced even when the hapten number, which was the higenamine molecules conjugated to the BSA molecule, was relatively low (approximately 4). The MAb was characterized and utilized in the established icELISA assay with a detectable range of 7.81 - 125 ng/mL. The assay limit of detection (LOD) was 4.41 ng/mL, indicating higher sensitivity than the conventional HPLC-UV methods. Various validation processes demonstrated that icELISA was precise, with the maximum CV (%) of the intra- and inter-assays of 11.58% and 10.18%, respectively. Moreover, the assay was accurate, with the recovery rates of spiked (S)-higenamine ranging from 82% to 113%, and sufficiently reliable for the detection of (S)-higenamine in various kinds of samples. Notably, the present study describes the first immunoassay for (S)-higenamine.


Assuntos
Alcaloides , Doping nos Esportes , Animais , Ensaio de Imunoadsorção Enzimática , Camundongos , Camundongos Endogâmicos BALB C , Tetra-Hidroisoquinolinas
12.
Medicine (Baltimore) ; 99(23): e20181, 2020 Jun 05.
Artigo em Inglês | MEDLINE | ID: mdl-32501970

RESUMO

BACKGROUND: This study will examine the effects of oxymatrine on the proliferation of human liver cancer Bel-7404 cells (HLCBC). METHODS: This study will search electronic bibliographic databases available in PUBMED, EMBASE, Cochrane Library, Scopus, Cumulative Index to Nursing and Allied Health Literature, China Biology Medicine, and China National Knowledge Infrastructure. We attempt to search case-controlled studies (CCSs) or randomized controlled studies (RCSs) pertaining to HLCBC from their inception to the February 29, 2020 without limitations of language and publication time. We will include any CCSs or RCSs on exploring oxymatrine on the proliferation of HLCBC. We will assess the methodological quality of CCSs by Newcastle-Ottawa Scale, and RCSs by Cochrane risk of bias tool. Review Manager 5.3 software will be utilized for statistical analysis. RESULTS: The current study will summarize most recent eligible studies to investigate the effects of oxymatrine on the proliferation of HLCBC. CONCLUSION: Its results may provide reliable scientific evidence on effects of oxymatrine on the proliferation of HLCBC. SYSTEMATIC REVIEW REGISTRATION: INPLASY202040026.


Assuntos
Alcaloides/farmacologia , Neoplasias Hepáticas/tratamento farmacológico , Quinolizinas/farmacologia , Proliferação de Células/efeitos dos fármacos , Relação Dose-Resposta a Droga , Fator de Transcrição E2F1/biossíntese , Expressão Gênica , Genes myc/efeitos dos fármacos , Humanos , Reação em Cadeia da Polimerase em Tempo Real , Projetos de Pesquisa
13.
Chem Biol Interact ; 327: 109146, 2020 Aug 25.
Artigo em Inglês | MEDLINE | ID: mdl-32561335

RESUMO

Evodiae Fructus (EF), the dried nearly mature scented fruit of Tetradium ruticarpum (A.Juss.) T.G.Hartley, was typically used to treat headache, abdominal pain, hernias, and menorrhagia for thousands of years. It had been reported to be a mild toxic herb through metabolic activation mainly by CYP3A but was barely explained from pharmacokinetic interaction. The aim of the study was to investigate the role of CYP3A inducer/inhibitor in pharmacokinetics of five alkaloids (evodiamine (EVOD), rutaecarpine (RUTA), 1-methyl-2-undecyl-4(1H)-quinolone (MUDQ), 1-methyl-2-nonyl-4(1H)-quinolone (MNNQ) and evocarpine (EVOC)) associated with hepatotoxicity of EF in Sprague Dawley (SD) rats. The results demonstrated that the metabolism of the five alkaloids of EF were inhibited in presence of CYP3A inhibitor whereas the metabolism of the five alkaloids of EF were promoted in presence of CYP3A inducer. Therefore, the dose is required attention when EF is taken in conjunction with CYP3A inducer as there is an enhancement in drug metabolism, which might lead to toxicity.


Assuntos
Alcaloides/farmacocinética , Indutores do Citocromo P-450 CYP3A/farmacologia , Inibidores do Citocromo P-450 CYP3A/farmacologia , Evodia/química , Alcaloides/sangue , Alcaloides/isolamento & purificação , Animais , Cromatografia Líquida de Alta Pressão , Dexametasona/farmacologia , Meia-Vida , Cetoconazol/farmacologia , Masculino , Ratos , Ratos Sprague-Dawley , Espectrometria de Massas em Tandem
14.
Nat Commun ; 11(1): 3236, 2020 06 26.
Artigo em Inglês | MEDLINE | ID: mdl-32591543

RESUMO

The promotion of apoptosis in tumor cells is a popular strategy for developing anti-cancer drugs. Here, we demonstrate that the plant indole alkaloid natural product nauclefine induces apoptosis of diverse cancer cells via a PDE3A-SLFN12 dependent death pathway. Nauclefine binds PDE3A but does not inhibit the PDE3A's phosphodiesterase activity, thus representing a previously unknown type of PDE3A modulator that can initiate apoptosis without affecting PDE3A's canonical function. We demonstrate that PDE3A's H840, Q975, Q1001, and F1004 residues-as well as I105 in SLFN12-are essential for nauclefine-induced PDE3A-SLFN12 interaction and cell death. Extending these molecular insights, we show in vivo that nauclefine inhibits tumor xenograft growth, doing so in a PDE3A- and SLFN12-dependent manner. Thus, beyond demonstrating potent cytotoxic effects of an alkaloid natural product, our study illustrates a potentially side-effect-reducing strategy for targeting PDE3A for anti-cancer therapeutics without affecting its phosphodiesterase activity.


Assuntos
Alcaloides/farmacologia , Apoptose/efeitos dos fármacos , Nucleotídeo Cíclico Fosfodiesterase do Tipo 3/metabolismo , Peptídeos e Proteínas de Sinalização Intracelular/metabolismo , Alcaloides/química , Animais , Linhagem Celular Tumoral , Proliferação de Células/efeitos dos fármacos , Sobrevivência Celular/efeitos dos fármacos , Cilostazol/farmacologia , Feminino , Humanos , Camundongos Nus , Inibidores da Fosfodiesterase 3/farmacologia , Estabilidade Proteica/efeitos dos fármacos , Tetra-Hidroisoquinolinas/farmacologia , Ensaios Antitumorais Modelo de Xenoenxerto
15.
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
16.
PLoS One ; 15(6): e0234639, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-32525924

RESUMO

BACKGROUND AND AIM: Kratom, or Mitragyna speciosa Korth., is a tropical plant that has been reported to exhibit opioid-like effects. Although opioids have been demonstrated to alter the lipid profile of regular users, data on the lipid-altering effects of kratom are scarce. This study aimed to compare the fasting lipid profile of regular kratom users to that of healthy subjects who do not use kratom. It also determined the association between various characteristics of kratom users and the serum triglycerides, total cholesterol, low-density lipoprotein (LDL), and high-density lipoprotein (HDL) levels of regular kratom users. METHODS: A total of 200 participants (n = 100 kratom users and n = 100 healthy subjects who do not use kratom) were recruited for this analytical cross-sectional study. Data on sociodemographic status, kratom use characteristics, cigarette smoking, physical activity, body mass index (BMI), fasting serum lipid profile, and liver function were collected from all participants. RESULTS: The liver parameters of the study participants were within normal range. The serum total cholesterol and LDL of kratom users were significantly lower than those of healthy subjects who do not use kratom. There were no significant differences in the serum triglyceride and HDL levels. However, higher average daily frequency of kratom use and increasing age were associated with increased serum total cholesterol among kratom users. Other kratom use characteristics such as age of first kratom intake, duration of kratom use, and quantity of daily kratom intake were not associated with increased serum triglyceride, total cholesterol, LDL, and HDL levels. CONCLUSIONS: Our findings suggest regular kratom consumption was not linked to elevated serum lipids, except when there is a higher frequency of daily kratom intake. However, the study was limited by the small sample size, and hence a more comprehensive study with larger sample size is warranted to confirm the findings.


Assuntos
Alcaloides/farmacologia , Drogas Ilícitas/farmacologia , Metabolismo dos Lipídeos , Mitragyna/química , Extratos Vegetais/farmacologia , Adulto , Estudos de Casos e Controles , Colesterol/sangue , Feminino , Humanos , Vida Independente , Lipoproteínas LDL/sangue , Fígado/efeitos dos fármacos , Fígado/metabolismo , Masculino , Triglicerídeos/sangue
17.
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
18.
Phytochemistry ; 177: 112424, 2020 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-32526514

RESUMO

In this study, we determined the pyridine alkaloid content (nicotine, nornicotine, anabasine, anatabine, cotinine, and myosmine) of 58 species and 2 subspecies of the Nicotiana genus by ultra-high-performance liquid chromatography coupled with mass spectrometry. We observed clear correlation between Noctiflorae and Suaveolentes sections and their above average accumulation of anabasine in the genus. In addition, the results demonstrated the presence of not only trace amounts but quantifiable levels of myosmine, an alkaloid previously detected in only minute quantities, in the leaves and roots of 16 species. In this study, analysis of gene expression of 58 species and 2 subspecies from the Nicotiana genus by mRNA sequencing was performed for the first time. Sequencing reads were mapped against annotated genes of a Nicotiana tabacum reference genome and expression values were subsequently calculated. Hierarchical clustering of alkaloid biosynthesis pathway genes and alkaloid content composition revealed patterns clearly segregating Nicotiana sections. Correlation of gene expression with alkaloid accumulation phenotypes was evident, including low putrescine methyltransferase expression for all species in the Suaveolentes section or clear correlation of nicotine demethylase with conversion rates of nicotine to nornicotine in the majority of species. Multiple additional correlations between alkaloid accumulation and gene expression values were identified, which makes this study an important fundament toward future scientific exploration of the Nicotiana genus.


Assuntos
Alcaloides , Tabaco/genética , Anabasina , Folhas de Planta , Transcriptoma
19.
Phytochemistry ; 177: 112435, 2020 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-32562919

RESUMO

Two alkaloids were isolated and identified for the first time in the black tubers of Tropaeolum tuberosum, collected from the Titicani-Taca, Ingavi province in La Paz, Bolivia. Their structures were elucidated by extensive NMR and MS spectroscopic analyses. The isolated compounds were evaluated for their cytotoxicity and apoptotic capacity against four human cancer cell lines. 2-Benzyl-3-thioxohexahydropyrrolo[1,2-c]imidazole-1-one (1) showed slight cytotoxic activity against all the cancer cell lines which were tested, with IC50 values ranging from 27.45 ± 0.80 to 31.07 ± 0.87 µM. Moreover, N-(4-acetyl-5-methyl-5-phenyl-4,5-dihydro-1,3,4-thiadiazol-2-yl) acetamide (2) showed significant anti-cancer potential, with IC50 values between 1.26 ± 0.57 µM and 1.37 ± 0.09 µM against all human cancer cell lines which were tested. Treatment of tumour cell lines with the compounds caused an increase in the apoptotic rate of these cells, observing that compound 2 presented an apoptotic effect which was double with respect to the control (Dimethylenastron).


Assuntos
Alcaloides , Antineoplásicos Fitogênicos , Tropaeolum , Bolívia , Linhagem Celular Tumoral , Humanos
20.
Emerg Microbes Infect ; 9(1): 1170-1173, 2020 Dec.
Artigo em Inglês | MEDLINE | ID: covidwho-324574

RESUMO

The emerging SARS-CoV-2 infection associated with the outbreak of viral pneumonia in China is ongoing worldwide. There are no approved antiviral therapies to treat this viral disease. Here we examined the antiviral abilities of three broad-spectrum antiviral compounds gemcitabine, lycorine and oxysophoridine against SARS-CoV-2 in cell culture. We found that all three tested compounds inhibited viral replication in Vero-E6 cells at noncytotoxic concentrations. The antiviral effect of gemcitabine was suppressed efficiently by the cytidine nucleosides. Additionally, combination of gemcitabine with oxysophoridine had an additive antiviral effect against SARS-CoV-2. Our results demonstrate that broad-spectrum antiviral compounds may have a priority for the screening of antiviral compounds against newly emerging viruses to control viral infection.


Assuntos
Alcaloides/farmacologia , Alcaloides de Amaryllidaceae/farmacologia , Antivirais/farmacologia , Betacoronavirus/efeitos dos fármacos , Desoxicitidina/análogos & derivados , Fenantridinas/farmacologia , Replicação Viral/efeitos dos fármacos , Animais , Betacoronavirus/crescimento & desenvolvimento , Betacoronavirus/metabolismo , Sobrevivência Celular/efeitos dos fármacos , Chlorocebus aethiops , Cloroquina/farmacologia , Desoxicitidina/farmacologia , Relação Dose-Resposta a Droga , Combinação de Medicamentos , Sinergismo Farmacológico , Células Vero
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