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1.
Nat Commun ; 15(1): 2084, 2024 Mar 07.
Artigo em Inglês | MEDLINE | ID: mdl-38453941

RESUMO

A major challenge to achieving industry-scale biomanufacturing of therapeutic alkaloids is the slow process of biocatalyst engineering. Amaryllidaceae alkaloids, such as the Alzheimer's medication galantamine, are complex plant secondary metabolites with recognized therapeutic value. Due to their difficult synthesis they are regularly sourced by extraction and purification from the low-yielding daffodil Narcissus pseudonarcissus. Here, we propose an efficient biosensor-machine learning technology stack for biocatalyst development, which we apply to engineer an Amaryllidaceae enzyme in Escherichia coli. Directed evolution is used to develop a highly sensitive (EC50 = 20 µM) and specific biosensor for the key Amaryllidaceae alkaloid branchpoint 4'-O-methylnorbelladine. A structure-based residual neural network (MutComputeX) is subsequently developed and used to generate activity-enriched variants of a plant methyltransferase, which are rapidly screened with the biosensor. Functional enzyme variants are identified that yield a 60% improvement in product titer, 2-fold higher catalytic activity, and 3-fold lower off-product regioisomer formation. A solved crystal structure elucidates the mechanism behind key beneficial mutations.


Assuntos
Alcaloides , Alcaloides de Amaryllidaceae , Amaryllidaceae , Narcissus , Amaryllidaceae/metabolismo , Alcaloides/química , Alcaloides de Amaryllidaceae/química , Alcaloides de Amaryllidaceae/metabolismo , Narcissus/química , Narcissus/genética , Narcissus/metabolismo , Metiltransferases/metabolismo , Plantas/metabolismo , Hidrolases/metabolismo
2.
Molecules ; 28(10)2023 May 12.
Artigo em Inglês | MEDLINE | ID: mdl-37241796

RESUMO

The alkaloids are one of the most represented family of natural occurring biological active compounds. Amaryllidaceae are also very well known for their beautiful flower and are thus used as ornamental plants in historic and public gardens. The Amaryllidacea alkaloids constitute an important group that is subdivided into different subfamilies with different carbon skeletons. They are well known from ancient times for their long application in folk medicine, and in particular, Narcissus poeticus L. was known to Hippocrates of Cos (ca. B.C. 460-370), who treated uterine tumors with a formulate prepared from narcissus oil. To date, more than 600 alkaloids of 15 chemical groups exhibiting various biological activities have been isolated from the Amaryllidaceae plants. This plant genus is diffused in regions of Southern Africa, Andean South America and the Mediterranean basin. Thus, this review describes the chemical and biological activity of the alkaloids collected in these regions in the last two decades as weel those of isocarbostyls isolated from Amaryllidaceae in the same regions and same period.


Assuntos
Alcaloides , Alcaloides de Amaryllidaceae , Amaryllidaceae , Narcissus , Extratos Vegetais/química , África do Sul , Narcissus/química , Alcaloides de Amaryllidaceae/química
3.
Molecules ; 28(3)2023 Jan 27.
Artigo em Inglês | MEDLINE | ID: mdl-36770905

RESUMO

Amaryllidaceae alkaloids are secondary metabolites with interesting medicinal properties. Almost every Narcissus species can synthesize them and constitute an excellent source for their isolation and study. Several Amaryllidaceae alkaloids have shown acetylcholinesterase inhibitory activities and are a promising tool for treating cholinergic disorders such as Alzheimer's disease (AD). Indeed, three of the four palliative treatments approved for AD are acetylcholinesterase (AChE) inhibitors and one of them, galanthamine, is an Amaryllidaceae alkaloid itself. This molecule is currently isolated from natural sources. However, its production is insufficient to supply the increasing demand for the active principle. Our main aim is to discover tools to improve galanthamine production and to prospect for potential new and more efficient drugs for AD treatment. Furthermore, we seek to broaden the knowledge of plants of the genus Narcissus from a chemotaxonomic perspective. Hence, in this study, we evaluate the alkaloid content through GC-MS and the AChE inhibitory activity of ten autumn-flowering Narcissus, which have been less studied than their spring-flowering counterparts. A total of thirty Amaryllidaceae alkaloids have been found, twenty-eight properly identified. Two Narcissus contained galanthamine, and seven were able to inhibit AChE.


Assuntos
Alcaloides de Amaryllidaceae , Amaryllidaceae , Narcissus , Acetilcolinesterase/metabolismo , Doença de Alzheimer/tratamento farmacológico , Amaryllidaceae/química , Alcaloides de Amaryllidaceae/farmacologia , Inibidores da Colinesterase , Galantamina/farmacologia , Narcissus/química
4.
Virus Res ; 315: 198768, 2022 07 02.
Artigo em Inglês | MEDLINE | ID: mdl-35398454

RESUMO

COVID-19 caused by SARS-CoV-2 virus has had profound impact on the world in the past two years. Intense research is going on to find effective drugs to combat the disease. Over the past year several vaccines were approved for immunization. But SARS-CoV-2 being an RNA virus is continuously mutating to generate new variants, some of which develop features of immune escape. This raised serious doubts over the long-term efficacy of the vaccines. We have identified a unique mannose binding plant lectin from Narcissus tazetta bulb, NTL-125, which effectively inhibits SARS-CoV-2 replication in Vero-E6 cell line. In silico docking studies revealed that NTL-125 has strong affinity to viral Spike RBD protein, preventing it from attaching to hACE2 receptor, the gateway to cellular entry. Binding analyses revealed that all the mutant variants of Spike protein also have stronger affinity for NTL-125 than hACE2. The unique α-helical tail of NTL-125 plays most important role in binding to RBD of Spike. NTL-125 also interacts effectively with some glycan moieties of S-protein in addition to amino acid residues adding to the binding strength. Thus, NTL-125 is a highly potential antiviral compound of natural origin against SARS-CoV-2 and may serve as an important therapeutic for management of COVID-19.


Assuntos
Enzima de Conversão de Angiotensina 2 , Lectinas de Plantas , SARS-CoV-2 , Glicoproteína da Espícula de Coronavírus , COVID-19 , Humanos , Narcissus/química , Lectinas de Plantas/farmacologia , Ligação Proteica , SARS-CoV-2/efeitos dos fármacos , Glicoproteína da Espícula de Coronavírus/antagonistas & inibidores , Glicoproteína da Espícula de Coronavírus/química
5.
Molecules ; 27(2)2022 Jan 06.
Artigo em Inglês | MEDLINE | ID: mdl-35056665

RESUMO

The flowers of Narcissus poeticus are used for the isolation of valuable fragrance substances. So far, as the majority of these substances consist of volatile and sensitive to heat compounds, there is a need of developing effective methods for their recovery. In this study, freeze-dried N. poeticus inflorescences were extracted with pure supercritical CO2 (SFE-CO2) and its mixture with 5% co-solvent ethanol (EtOH) at 40 °C. Extract yields varied from 1.63% (12 MPa) to 3.12% (48 MPa, 5% EtOH). In total, 116 volatile compounds were identified by GC-TOF/MS in the extracts, which were divided into 20 different groups. Benzyl benzoate (9.44-10.22%), benzyl linoleate (1.72-2.17%) and benzyl alcohol (0.18-1.00%) were the major volatiles among aromatic compounds. The amount of the recovered benzyl benzoate in N. poeticus SFE-CO2 extracts varied from 58.98 ± 2.61 (24 MPa) to 91.52 ± 1.36 (48 MPa) mg/kg plant dry weight (pdw). α-Terpineol dominated among oxygenated monoterpenes (1.08-3.42%); its yield was from 9.25 ± 0.63 (12 MPa) to 29.88 ± 1.25 (48 MPa/EtOH) mg/kg pdw. Limonene was the major monoterpene hydrocarbon; (3E)-hexenol and heneicosanol dominated among alcohols and phenols; dihydroactinidiolide and 4,8,12,16-tetramethyl heptadecan-4-olide were the most abundant lactones; heptanal, nonanal, (2E,4E)-decadienal and octadecanal were the most abundant aldehydes. The most important prenol lipids were triterpenoid squalene, from 0.86 ± 0.10 (24 MPa) to 7.73 ± 0.18 (48 MPa/EtOH) mg/kg pdw and D-α-tocopherol, from 1.20 ± 0.04 (12 MPa) to 15.39 ± 0.31 (48 MPa/EtOH) mg/kg pdw. Aliphatic hydrocarbons (waxes) constituted the main part (41.47 to 54.93%) in the extracts; while in case of a 5% EtOH the percentage of alkanes was the lowest. The fraction of waxes may be removed for the separation of higher value fragrance materials. In general, the results obtained are promising for a wider application of SFE-CO2 for the recovery of fragrance substances from N. poeticus flowers.


Assuntos
Dióxido de Carbono/química , Flores/química , Narcissus/química , Odorantes/análise , Óleos Voláteis/isolamento & purificação , Compostos Fitoquímicos/isolamento & purificação , Extratos Vegetais/isolamento & purificação , Perfumes/análise , Solventes/química
6.
Rapid Commun Mass Spectrom ; 35(14): e9116, 2021 Jul 31.
Artigo em Inglês | MEDLINE | ID: mdl-33928691

RESUMO

RATIONALE: Narcissus cv. Hawera has been found to biosynthesize some Sceletium-type alkaloids with antidepressant and anxiolytic activities. This ornamental plant has been poorly studied as a source of bioactive alkaloids including some contraversive reports on in vitro and intact plants. In this study, a detailed GC-MS characterization of its alkaloid fractions is presented. METHODS: GC-MS was used for the identification of compounds in the alkaloid fractions. Both underivatized and silylated samples were analyzed simultaneously. Elevated plus maze and tail suspension tests were used to assay the anxiolytic and antidepressant activities. Ellman's and MTT-dye reduction assays were used to evaluate the acetylcholinesterase (AChE) inhibitory and cytotoxicity activities, respectively. RESULTS: Of the 29 alkaloids, 13 of Sceletium-type were detected. Two new alkaloids were identified as 2-oxo-mesembrine and 2-oxo-epi-mesembrenol. Lycorine was found as a major compound (43.5%) in the crude silylated methanol extract. After the elimination of lycorine by pre-crystallization, the major alkaloids were 40.8% 6-epi-mesembranol, 16.2% 6-epi-mesembrenol, and 13.8% sanguinine. This fraction showed anxiolytic and antidepressant-like activities as well as potent AChE inhibitory and antineoplastic activities. CONCLUSIONS: Silylation of the alkaloid fractions from Narcissus cv. Hawera provides better separation, structural information, and improved sensitivity for compounds with two and more hydroxyl groups. The lycorine-free alkaloid fraction shows a great potential for further pharmacological studies.


Assuntos
Alcaloides , Cromatografia Gasosa-Espectrometria de Massas/métodos , Narcissus/química , Extratos Vegetais/química , Aizoaceae , Alcaloides/análise , Alcaloides/farmacologia , Alcaloides/toxicidade , Amaryllidaceae , Animais , Ansiolíticos/análise , Ansiolíticos/farmacologia , Ansiolíticos/toxicidade , Comportamento Animal/efeitos dos fármacos , Linhagem Celular Tumoral , Sobrevivência Celular/efeitos dos fármacos , Feminino , Humanos , Masculino , Camundongos , Camundongos Endogâmicos ICR
7.
Biointerphases ; 15(6): 061016, 2020 12 23.
Artigo em Inglês | MEDLINE | ID: mdl-33356336

RESUMO

There are many different types of surfaces found in nature which can increase or reduce friction, such as the well-studied frog toe or lotus leaf. However, methods for replicating these surfaces on a large scale for use in industrial applications are needed in order to take advantage of this natural friction engineering. Most replication processes rely on molding that requires an input surface size comparable to the desired output surface. We present a novel approach of replicating large-scale biosurfaces using a laser scanning confocal microscope for surface digitization and 3D two-photon lithography for the fabrication of the digitized surface. Two different natural surfaces (banana skin and daffodil petal) were replicated. An intermediary tiling process was used to cover a target area of arbitrary size independent of the input texture size. The surfaces were coated with a thin layer of ZnO, and the frictional and wettability characteristics of the replicated surfaces were then examined, demonstrating significant friction reduction up to 42% and increased hydrophobicity due to the presence of texture.


Assuntos
Materiais Biomiméticos/química , Fricção/fisiologia , Frutas/química , Microscopia Confocal , Musa/química , Narcissus/química , Propriedades de Superfície , Compostos de Estanho/química , Óxido de Zinco/química
8.
Biomolecules ; 10(5)2020 05 22.
Artigo em Inglês | MEDLINE | ID: mdl-32455879

RESUMO

Thirteen known (1-12 and 16) and three previously undescribed Amaryllidaceae alkaloids of belladine structural type, named carltonine A-C (13-15), were isolated from bulbs of Narcissus pseudonarcissus cv. Carlton (Amaryllidaceae) by standard chromatographic methods. Compounds isolated in sufficient amounts, and not tested previously, were evaluated for their in vitro acetylcholinesterase (AChE; E.C. 3.1.1.7), butyrylcholinesterase (BuChE; E.C. 3.1.1.8) and prolyl oligopeptidase (POP; E.C. 3.4.21.26) inhibition activities. Significant human BuChE (hBUChE) inhibitory activity was demonstrated by newly described alkaloids carltonine A (13) and carltonine B (14) with IC50 values of 913 ± 20 nM and 31 ± 1 nM, respectively. Both compounds displayed a selective inhibition pattern for hBuChE with an outstanding selectivity profile over AChE inhibition, higher than 100. The in vitro data were further supported by in silico studies of the active alkaloids 13 and 14 in the active site of hBuChE.


Assuntos
Alcaloides/farmacologia , Butirilcolinesterase/metabolismo , Inibidores da Colinesterase/farmacologia , Narcissus/química , Alcaloides/química , Sítios de Ligação , Butirilcolinesterase/química , Inibidores da Colinesterase/química , Humanos , Simulação de Acoplamento Molecular , Ligação Proteica
9.
BMC Cancer ; 20(1): 192, 2020 Mar 06.
Artigo em Inglês | MEDLINE | ID: mdl-32143591

RESUMO

BACKGROUND: Altered glycosylation associated with hepatocellular carcinoma (HCC) is well documented. However, few reports have investigated the association between dedifferentiation and glycosylation. Therefore, the aim of this study was to analyze glycosylation associated with dedifferentiation of HCC within the same nodule and to investigate glycosyltransferase related to the glycosylation. METHODS: We analyzed resected HCC specimens (n = 50) using lectin microarray to comprehensively and sensitively analyze glycan profiles, and identify changes to glycosylation between well- and moderately-differentiated components within the same nodule. Moreover, we performed immunohistochemical staining of mannosyl(α-1,3-)-glycoprotein ß-1,2-N-acetylglucosaminyltransferase (MGAT1), which is an essential glycosyltransferase that converts high-mannose glycans to complex- or hybrid-type N-glycans. RESULTS: Four lectins from Narcissus pseudonarcissus agglutinin (NPA), Concanavalin A, Galanthus nivalis agglutinin, and Calystegia sepium agglutinin were significantly elevated in moderately-differentiated components of HCC compared with well-differentiated components, and all lectins showed binding specificity to high-mannose glycans. Therefore, these structures were represented to a greater extent in moderately-differentiated components than in well-differentiated ones. Immunohistochemical staining revealed significantly increased NPA expression and decreased MGAT1 expression in moderately-differentiated components. Low MGAT1 expression in moderately-differentiated components of tumors was associated with intrahepatic metastasis and had tendency for poor prognosis. CONCLUSION: Dedifferentiation of well-differentiated HCC is associated with an increase in high-mannose glycans. MGAT1 may play a role in the dedifferentiation of HCC.


Assuntos
Carcinoma Hepatocelular/metabolismo , Concanavalina A/metabolismo , Neoplasias Hepáticas/metabolismo , Lectinas de Ligação a Manose/metabolismo , Lectinas de Plantas/metabolismo , Idoso , Calystegia/química , Carcinoma Hepatocelular/patologia , Carcinoma Hepatocelular/cirurgia , Intervalo Livre de Doença , Feminino , Glicosilação , Humanos , Imuno-Histoquímica/métodos , Neoplasias Hepáticas/patologia , Neoplasias Hepáticas/cirurgia , Masculino , N-Acetilglucosaminiltransferases/metabolismo , Narcissus/química , Imagem Óptica/métodos , Polissacarídeos/química , Coloração e Rotulagem/métodos
10.
Nat Prod Res ; 34(14): 2051-2058, 2020 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-30784301

RESUMO

A new N-oxide, Pseudolycorine N-oxide (1) was characterised along with eleven known alkaloids homolycorine (2), O-methylmaritidine (3), 8-O-demethylhomolycorine (4), homolycorine N-oxide (5), lycorine (6), narciclasine (7), pseudolycorine (8), ungeremine (9), 8-O-demethylmaritidine (10), zefbetaine (11) and lycorine N-oxide (12), from Narcissus tazetta. Their structures were established on the basis of spectroscopic data analysis. The extract, fractions and isolated compounds were screened for in vitro cytotoxicity against two human cancer cell lines, human cervical cancer (SiHa) and human epidermoid carcinoma (KB) cells. The study demonstrated the cytotoxic potential of extract and its chloroform and n-butanol fractions. Further, the results revealed the bioactive potential of narciclasine, pseudolycorine and homolycorine alkaloids. However, new N-oxide (1) was not active against these cell lines.


Assuntos
Alcaloides/isolamento & purificação , Alcaloides de Amaryllidaceae/isolamento & purificação , Antineoplásicos Fitogênicos/isolamento & purificação , Narcissus/química , Óxidos/isolamento & purificação , Fenantridinas/isolamento & purificação , Extratos Vegetais/química , Alcaloides/química , Alcaloides de Amaryllidaceae/análise , Alcaloides de Amaryllidaceae/química , Antineoplásicos Fitogênicos/química , Antineoplásicos Fitogênicos/farmacologia , Linhagem Celular Tumoral , Humanos , Indolizinas/análise , Óxidos/química , Fenantridinas/análise , Fenantridinas/química
11.
Biochim Biophys Acta Bioenerg ; 1861(2): 148117, 2020 02 01.
Artigo em Inglês | MEDLINE | ID: mdl-31734197

RESUMO

The xanthophyll cycle is a regulatory mechanism operating in the photosynthetic apparatus of plants. It consists of the conversion of the xanthophyll pigment violaxanthin to zeaxanthin, and vice versa, in response to light intensity. According to the current understanding, one of the modes of regulatory activity of the cycle is associated with the influence on a molecular organization of pigment-protein complexes. In the present work, we analyzed the effect of violaxanthin and zeaxanthin on the molecular organization of the LHCII complex, in the environment of membranes formed with chloroplast lipids. Nanoscale imaging based on atomic force microscopy (AFM) showed that the presence of exogenous xanthophylls promotes the formation of the protein supramolecular structures. Nanoscale infrared (IR) absorption analysis based on AFM-IR nanospectroscopy suggests that zeaxanthin promotes the formation of LHCII supramolecular structures by forming inter-molecular ß-structures. Meanwhile, the molecules of violaxanthin act as "molecular spacers" preventing self-aggregation of the protein, potentially leading to uncontrolled dissipation of excitation energy in the complex. This latter mechanism was demonstrated with the application of fluorescence lifetime imaging microscopy. The intensity-averaged chlorophyll a fluorescence lifetime determined in the LHCII samples without exogenous xanthophylls at the level of 0.72 ns was longer in the samples containing exogenous violaxanthin (2.14 ns), but shorter under the presence of zeaxanthin (0.49 ns) thus suggesting a role of this xanthophyll in promotion of the formation of structures characterized by effective excitation quenching. This mechanism can be considered as a representation of the overall photoprotective activity of the xanthophyll cycle.


Assuntos
Membranas Intracelulares/enzimologia , Complexos de Proteínas Captadores de Luz/química , Narcissus/química , Spinacia oleracea/enzimologia , Zeaxantinas/química , Clorofila A/química , Estrutura Secundária de Proteína , Xantofilas/química
12.
Phytochemistry ; 165: 112055, 2019 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-31261031

RESUMO

Twenty-one known Amaryllidaceae alkaloids of various structural types and one undescribed alkaloid, named narcimatuline, have been isolated from fresh bulbs of Narcissus pseudonarcissus L. cv. Dutch Master. The chemical structures were elucidated by combination of MS, HRMS, 1D and 2D NMR spectroscopic techniques, and by comparison with literature data. Narcimatuline amalgamates two basic scaffolds of Amaryllidaceae alkaloids in its core, namely galanthamine and galanthindole. All isolated compounds were evaluated for their in vitro acetylcholinesterase (AChE), butyrylcholinesterase (BuChE), prolyl oligopeptidase (POP), and glycogen synthase kinase-3ß (GSK-3ß) inhibitory activities. The most interesting biological profile was demonstrated by newly isolated alkaloid narcimatuline.


Assuntos
Doença de Alzheimer/tratamento farmacológico , Alcaloides de Amaryllidaceae/farmacologia , Inibidores da Colinesterase/farmacologia , Narcissus/química , Fármacos Neuroprotetores/farmacologia , Acetilcolinesterase/metabolismo , Doença de Alzheimer/metabolismo , Alcaloides de Amaryllidaceae/química , Alcaloides de Amaryllidaceae/isolamento & purificação , Butirilcolinesterase/metabolismo , Inibidores da Colinesterase/química , Inibidores da Colinesterase/isolamento & purificação , Relação Dose-Resposta a Droga , Glicogênio Sintase Quinase 3 beta/antagonistas & inibidores , Glicogênio Sintase Quinase 3 beta/metabolismo , Humanos , Estrutura Molecular , Fármacos Neuroprotetores/química , Fármacos Neuroprotetores/isolamento & purificação , Prolil Oligopeptidases , Serina Endopeptidases/metabolismo , Relação Estrutura-Atividade
13.
J Pharm Biomed Anal ; 175: 112750, 2019 Oct 25.
Artigo em Inglês | MEDLINE | ID: mdl-31330284

RESUMO

Narcissus tazetta is used traditionally for treatment of sores, wounds, skin diseases, cancer in different parts of world. Present study focus on the analysis of amaryllidaceae alkaloids in this plant using an ultra-performance liquid chromatography-diode array detection method. The method was developed for simultaneous quantification of eight Amaryllidaceae alkaloids i.e. pseudolycorine (1), lycorine (2), galanthamine (3), 8-O-demethylhomolycorine (4), N-methylhaemanthidine chloride (5), homolycorine (6), narciclasine (7) and zefbetaine (8) in Narcissus tazetta. The method was validated using a BEH C18 column with linear gradient. Standard calibration curve for the analytes showed good linearity ( r2≥0.999). The method was validated for intra-day (RSDs<0.91%) and inter-day (RSDs<0.65%) precisions and accuracy (recovery 92.2-112.5%). The developed method was successively applied for studying the variation of alkaloids in different parts of Narcissus tazetta, i.e. bulbs, roots, flowers, flower stalks and leaves. The study showed a significant variation of these alkaloids in different parts of the plant. Among the alkaloids under investigation, pseudolycorine had highest content in all the parts. Furthermore, application of the developed method to the identification of phytocomponents allowed the identification of sixteen alkaloids.


Assuntos
Alcaloides de Amaryllidaceae/química , Narcissus/química , Extratos Vegetais/química , Cromatografia Líquida de Alta Pressão/métodos , Flores/química , Galantamina/química , Fenantridinas/química , Folhas de Planta/química , Raízes de Plantas/química , Espectrometria de Massas por Ionização por Electrospray/métodos , Espectrometria de Massas em Tandem/métodos
14.
J Pharm Biomed Anal ; 172: 230-237, 2019 Aug 05.
Artigo em Inglês | MEDLINE | ID: mdl-31060036

RESUMO

Narcissus spp. are an economically important crop for medicines in relation with the alkaloids production, mainly galanthamine, an acetylcholinesterase inhibitor used for the treatment of Alzheimer's disease. In this article an extensively study of the phytochemistry of both bulbs of different species and varieties of Narcissus grown in Iran and in vitro culture of these plants was investigated. In particular, the Amaryllidaceae alkaloid profile and the galanthamine and lycorine contents in wild bulbs of Narcissus papyraceus (G5) and four varieties of Narcissus tazetta (N. tazetta var. Shahla (G4), N. tazetta var. Shastpar (G1), N. tazetta var. Meskin (G2), N. tazetta var. Panjehgorbei (G3)), growing in Iran are reported. The alkaloid profiles were investigated by GC-MS and LC-MS and the quantitative analysis was performed using GC-MS. In total, thirty alkaloids were identified among them nine alkaloids were observed with the both methods of analysis. The variety Meskin of N. tazetta (G2), showed the highest diversity of alkaloids and the highest content in galanthamine. On this last species (G2) and on N. tazetta var. Shahla (G4), the effects of auxins 2,4-dichlorophenoxyacetic acid (2,4-D), 4-amino-3,5,6-trichloropicolinic acid (Picloram) and naphthalene acetic acid (NAA) at concentrations of 25 and 50 µM were studied on the induction of callus and its capacity to induce organogenesis and alkaloid diversity. All auxins, at the concentrations of 25 and 50 µM, produced calli. Bulblets and roots were formed on calli grown only in the presence of 25 or 50 µM NAA. GC-MS analyses showed the presence of galanthamine and lycorine in calli, roots and bulblets, with all auxins whatever the concentration used while demethylmaritidine and tazettine were found in differentiated tissue cultures cultivated on the medium containing NAA (25 or 50 µM) or in calli initiated with Picloram (50 µM). Precursor 4'-O-methylnorbelladine (MN) of Amaryllidaceae alkaloids feeding was found to significantly improve the accumulation of both galanthamine (82 µg/g DW) and lycorine (1800 µg/g DW) in bulblets of N. tazetta var. Meskin (G2).


Assuntos
Alcaloides de Amaryllidaceae/química , Narcissus/química , Inibidores da Colinesterase/química , Galantamina/química , Cromatografia Gasosa-Espectrometria de Massas/métodos , Irã (Geográfico) , Fenantridinas/química , Extratos Vegetais/química , Raízes de Plantas/química
15.
Nat Prod Res ; 33(15): 2281-2284, 2019 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-30375245

RESUMO

Narcissus pseudonarcissus (daffodil) is a valuable plant for the cosmetic, pharmaceutical and therapeutical traits. The flower volatile compounds (FVCs) of ten Narcissus pseudonarcissus cultivars were analyzed by Headspace/Solid Phase Micro Extraction-Gas Chromatography Mass Spectrometry (HS/SPME- GC/MS). 69 and 73 FVCs were detected in perianth and corona of the ten cultivars. The compounds are largely comprised of monoterpenes, sesquiterpene, benzenoid compounds and other minor compounds classes. Monoterpenes were major component among the FVCs, with beta-ocimene and beta-myrcene as the two major compounds in most perianths and coronas. The composition and content of the FVCs of different cultivars are quite different from each other.


Assuntos
Narcissus/química , Compostos Orgânicos Voláteis/análise , Monoterpenos Acíclicos , Alcenos/análise , Cromatografia Gasosa-Espectrometria de Massas/métodos , Monoterpenos/análise , Sesquiterpenos/análise , Microextração em Fase Sólida/métodos
16.
Int J Mol Sci ; 19(11)2018 Oct 26.
Artigo em Inglês | MEDLINE | ID: mdl-30373163

RESUMO

Since the skin is the major protective barrier of the body, it is affected by intrinsic and extrinsic factors. Environmental influences such as ultraviolet (UV) irradiation, pollution or dry/cold air are involved in the generation of radical oxygen species (ROS) and impact skin aging and dermal health. Assessment of human skin gene expression and other biomarkers including epigenetic factors are used to evaluate the biological/molecular activities of key compounds in cosmetic formulas. The objective of this study was to quantify human gene expression when epidermal full-thickness skin equivalents were exposed to: (a) a mixture of betaine, pentylene glycol, Saccharomyces cerevisiae and Rhodiola rosea root extract (BlendE) for antioxidant, skin barrier function and oxidative stress (with hydrogen peroxide challenge); and (b) a mixture of Narcissus tazetta bulb extract and Schisandra chinensis fruit extract (BlendIP) for various biomarkers and microRNA analysis. For BlendE, several antioxidants, protective oxidative stress biomarkers and many skin barrier function parameters were significantly increased. When BlendE was evaluated, the negative impact of the hydrogen peroxide was significantly reduced for the matrix metalloproteinases (MMP 3 and MMP 12), the skin aging and oxidative stress biomarkers, namely FBN2, ANXA1 and HGF. When BlendIP was tested for cell proliferation and dermal structural components to enhance the integrity of the skin around the eyes: 8 growth factors, 7 signaling, 7 structural/barrier function and 7 oxidative stress biomarkers were significantly increased. Finally, when BlendIP was tested via real-time RT-PCR for microRNA expression: miR-146a, miR-22, miR155, miR16 and miR21 were all significantly increased over control levels. Therefore, human skin gene expression studies are important tools to assess active ingredient compounds such as plant extract blends to advance dermal hypotheses toward validating cosmetic formulations with botanical molecules.


Assuntos
Antioxidantes/farmacologia , Regulação da Expressão Gênica/efeitos dos fármacos , Extratos Vegetais/farmacologia , Plantas Medicinais , Envelhecimento da Pele/efeitos dos fármacos , Pele/efeitos dos fármacos , Antioxidantes/química , Epigênese Genética/efeitos dos fármacos , Humanos , MicroRNAs/genética , Narcissus/química , Estresse Oxidativo/efeitos dos fármacos , Extratos Vegetais/química , Plantas Medicinais/química , Rhodiola/química , Schisandra/química , Pele/metabolismo , Pele/efeitos da radiação , Envelhecimento da Pele/efeitos da radiação , Raios Ultravioleta/efeitos adversos
17.
Artigo em Inglês | MEDLINE | ID: mdl-29870924

RESUMO

Supercritical fluid chromatography hyphenated with high resolution mass spectrometry (SFC-HRMS) was developed for fingerprint analysis of different flower absolutes commonly used in cosmetics field, especially in perfumes. Supercritical fluid chromatography-atmospheric pressure photoionization-high resolution mass spectrometry (SFC-APPI-HRMS) technique was employed to identify the components of the fingerprint. The samples were separated with a porous graphitic carbon (PGC) Hypercarb™ column (100 mm × 2.1 mm, 3 µm) by gradient elution using supercritical CO2 and ethanol (0.0-20.0 min (2-30% B), 20.0-25.0 min (30% B), 25.0-26.0 min (30-2% B) and 26.0-30.0 min (2% B)) as mobile phase at a flow rate of 1.5 mL/min. In order to compare the SFC fingerprints between five different flower absolutes: Jasminum grandiflorum absolutes, Jasminum sambac absolutes, Narcissus jonquilla absolutes, Narcissus poeticus absolutes, Lavandula angustifolia absolutes from different suppliers and batches, the chemometric procedure including principal component analysis (PCA) was applied to classify the samples according to their genus and their species. Consistent results were obtained to show that samples could be successfully discriminated.


Assuntos
Cromatografia com Fluido Supercrítico/métodos , Flores/química , Espectrometria de Massas/métodos , Extratos Vegetais/análise , Cromatografia por Troca Iônica , Cosméticos , Flores/classificação , Jasminum/química , Lavandula/química , Narcissus/química , Extratos Vegetais/química , Análise de Componente Principal
18.
J Nat Prod ; 81(6): 1451-1459, 2018 06 22.
Artigo em Inglês | MEDLINE | ID: mdl-29787267

RESUMO

An efficient protocol for the isolation of narciclasine from common Amaryllidaceae bulbs, separation from haemanthamine, and the occurrence of a trace alkaloid, 2- epi-narciclasine, are reported. Attempts to convert natural narciclasine to its C-2 epimer by Mitsunobu inversion or oxidation/reduction sequences were compromised by rearrangement and aromatization processes, through which a synthesis of the alkaloid narciprimine was achieved. The methylation of the 7-hydroxy group of natural narciclasine followed by protection of the 3,4-diol function and oxidation/reduction sequence provided the target C-2 epimer. A de novo chemoenzymatic synthesis of 2- epi-narciclasine from m-dibromobenzene is also described. Haemanthamine and narciprimine were readily detected in the crude extracts of Narcissus and Galanthus bulbs containing narciclasine, and the occurrence of 2- epi-narciclasine as a trace natural product in Galanthus sp. is reported for the first time.


Assuntos
Alcaloides de Amaryllidaceae/química , Amaryllidaceae/química , Galanthus/química , Narcissus/química , Fenantridinas/química , Alcaloides/química , Oxirredução , Fenantrenos/química , Raízes de Plantas/química
19.
Glycobiology ; 27(12): 1134-1143, 2017 12 01.
Artigo em Inglês | MEDLINE | ID: mdl-28973355

RESUMO

Our understanding of muscle glycosylation to date has derived from studies in mouse models and a limited number of human lectin histochemistry studies. As various therapeutic approaches aimed at treating patients with muscular dystrophies are being translated from rodent models to human, it is critical to better understand human muscle glycosylation and relevant disease-specific differences between healthy and dystrophic muscle. Here, we report the first quantitative characterization of human muscle glycosylation, and identify differentiation- and disease-specific differences in human muscle glycosylation. Utilizing a panel of 13 lectins with varying glycan specificities, we surveyed lectin binding to primary and immortalized myoblasts and myotubes from healthy and dystrophic sources. Following differentiation of primary and immortalized healthy human muscle cells, we observed increased binding of Narcissus pseudonarcissus agglutinin (NPA), PNA, MAA-II and WFA to myotubes compared to myoblasts. Following differentiation of immortalized healthy and dystrophic human muscle cells, we observed disease-specific differences in binding of NPA, Jac and Tricosanthes japonica agglutinin-I (TJA-I) to differentiated myotubes. We also observed differentiation- and disease-specific differences in binding of NPA, Jac, PNA, TJA-I and WFA to glycoprotein receptors in muscle cells. Additionally, Jac, PNA and WFA precipitated functionally glycosylated α-DG, that bound laminin, while NPA and TJA-I did not. Lectin histochemistry of healthy and dystrophic human muscle sections identified disease-specific differences in binding of O-glycan and sialic acid-specific lectins between healthy and dystrophic muscle. These results indicate that specific and discrete changes in glycosylation occur following differentiation, and identify specific lectins as potential biomarkers sensitive to changes in healthy human muscle glycosylation.


Assuntos
Glicoproteínas/metabolismo , Proteínas Musculares/metabolismo , Distrofias Musculares/metabolismo , Mioblastos Esqueléticos/metabolismo , Narcissus/química , Lectinas de Plantas/farmacologia , Linhagem Celular Transformada , Glicoproteínas/química , Humanos , Proteínas Musculares/química , Distrofias Musculares/patologia , Mioblastos Esqueléticos/química , Mioblastos Esqueléticos/patologia , Lectinas de Plantas/química
20.
Nat Prod Commun ; 12(1): 15-18, 2017 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-30549814

RESUMO

Species of Narcissus (family Amaryllidaceae) are a potential source for large-scale extraction of alkaloids and fragrances. The bulbs typically accumulate a large number of alkaloids, including galantamine, a benzazepine alkaloid proven to be a cholinesterase inhibitor and which is used in the treatment of Alzheimer's disease. The presence of galantamine in N. poeticus L. collected in Abruzzo (Italy) was assessed and several levels of alkaloid were found in all parts of the plant (flower, stem, bulb and root) and not only in the bulb. The amount of galantamine obtained was tested by using two different extraction solvents. Extraction of N. poeticus absolute from the flowers was also performed, as this product is an important floral note in perfumery, and the distribution of allergenic compounds in the coronas and in the tepals was assessed. Moreover, the in vitro propagation of N.:Poeticus was tested as it may be a valuable resource from which to produce biomolecules, as an alternative to chemical synthetic processes.


Assuntos
Alérgenos/análise , Flores/química , Galantamina/análise , Narcissus/química , Cromatografia Gasosa-Espectrometria de Massas , Itália , Óleos Voláteis/análise , Perfumes , Extratos Vegetais/química , Raízes de Plantas/química
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