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1.
Zhongguo Zhong Yao Za Zhi ; 46(20): 5304-5309, 2021 Oct.
Artigo em Chinês | MEDLINE | ID: mdl-34738433

RESUMO

Perennial herb Hymenocallis littoralis(Amaryllidaceae) boasts anti-tumor, anti-virus, and anti-inflammatory activities. As the representative constituents, alkaloids have attracted much attention, whereas the non-alkaloid constituents have been rarely reported. Therefore, this study investigated the non-alkaloid constituents of H. littoralis and their contribution to the various pharmacological activities of the herb. Thirteen non-alkaloid compounds were isolated from the 95% ethanol extract of dried whole plant of H. littoralis after a series of chromatographic separation steps and spectral analysis, and they were identified as 5,7-dihydroxy-6,8-dimethoxy-2-hydroxymethyl-4H-chromoen-4-one(1), undulatoside A(2),(2S)-7,4'-dihydroxyflavane(3), naringenin(4), 4',7-hydroxy-8-methylflavanone(5), 8-methylnaringenin(6), 8-demethylfarrerol(7), 6-methyl-aromadendrin(8), 4',5,7-trihydroxy-8-methylflavanone(9), syzalterin(10), 6-methylapigenin(11), isoliquiritigenin(12), and undatuside C(13) based on the spectroscopic data analysis. Among them, compound 1 was a new chromone derivative, and compounds 2 and 4-13 were isolated form this plant for the first time.


Assuntos
Alcaloides , Amaryllidaceae , Liliaceae , Cromonas
2.
Molecules ; 26(13)2021 Jun 30.
Artigo em Inglês | MEDLINE | ID: mdl-34208814

RESUMO

Parkinson's disease (PD) is one of the most common neurodegenerative diseases and affects approximately 6.3 million people worldwide. To date, the treatment of PD remains a challenge, as available treatment options are known to be associated with serious side effects; hence, the search for new treatment strategies is critical. Extracts from the Amaryllidaceae plant family as well as their alkaloids have been reported to have neuroprotective potentials. This study, therefore, investigated the biological activities of Crossyne flava and its isolated alkaloids in an in vitro MPP+ (1-methyl-4-phenylpyridinium) PD model using SH-SY5Y cells. The effects of the total extract as well as the four compounds isolated from Crossyne flava (i.e., pancratinine B (1), bufanidrine (2), buphanisine (3), and epibuphanisine (4)) were evaluated for cell viability, neuroprotection, levels of reactive oxygen species (ROS), adenosine triphosphate activity (ATP), and caspase 3/7 activity in SH-SY5Y cells. The results obtained showed that pre-treatment with both the extract and the isolated compounds was effective in protecting the SH-SY5Y cells from MPP+-induced neurotoxicity and inhibited ROS generation, ATP depletion as well as apoptosis induction in the SH-SY5Y cells. The results of this study show that the Amaryllidaceae plant family may be a source of novel compounds for the treatment of neurodegenerative diseases, which validates the reported traditional uses.


Assuntos
Alcaloides de Amaryllidaceae/farmacologia , Amaryllidaceae/química , Intoxicação por MPTP/tratamento farmacológico , Fármacos Neuroprotetores/farmacologia , Estresse Oxidativo/efeitos dos fármacos , Transdução de Sinais/efeitos dos fármacos , Alcaloides de Amaryllidaceae/química , Alcaloides de Amaryllidaceae/isolamento & purificação , Linhagem Celular Tumoral , Humanos , Intoxicação por MPTP/metabolismo , Intoxicação por MPTP/patologia , Neuroproteção/efeitos dos fármacos , Fármacos Neuroprotetores/química , Fármacos Neuroprotetores/isolamento & purificação
3.
Int J Mol Sci ; 22(13)2021 Jun 29.
Artigo em Inglês | MEDLINE | ID: mdl-34209868

RESUMO

Pancracine, a montanine-type Amaryllidaceae alkaloid (AA), is one of the most potent compounds among natural isoquinolines. In previous studies, pancracine exhibited cytotoxic activity against diverse human cancer cell lines in vitro. However, further insight into the molecular mechanisms that underlie the cytotoxic effect of pancracine have not been reported and remain unknown. To fill this void, the cell proliferation and viability of cancer cells was explored using the Trypan Blue assay or by using the xCELLigence system. The impact on the cell cycle was determined by flow cytometry. Apoptosis was evaluated by Annexin V/PI and by quantifying the activity of caspases (-3/7, -8, and -9). Proteins triggering growth arrest or apoptosis were detected by Western blotting. Pancracine has strong antiproliferative activity on A549 cells, lasting up to 96 h, and antiproliferative and cytotoxic effects on MOLT-4 cells. The apoptosis-inducing activity of pancracine in MOLT-4 cells was evidenced by the significantly higher activity of caspases. This was transmitted through the upregulation of p53 phosphorylated on Ser392, p38 MAPK phosphorylated on Thr180/Tyr182, and upregulation of p27. The pancracine treatment negatively altered the proliferation of A549 cells as a consequence of an increase in G1-phase accumulation, associated with the downregulation of Rb phosphorylated on Ser807/811 and with the concomitant upregulation of p27 and downregulation of Akt phosphorylated on Thr308. This was the first study to glean a deeper mechanistic understanding of pancracine activity in vitro. Perturbation of the cell cycle and induction of apoptotic cell death were considered key mechanisms of pancracine action.


Assuntos
Adenocarcinoma de Pulmão/patologia , Proliferação de Células/efeitos dos fármacos , Compostos Heterocíclicos de 4 ou mais Anéis/farmacologia , Leucemia/patologia , Neoplasias Pulmonares/patologia , Células A549 , Alcaloides/isolamento & purificação , Alcaloides/farmacologia , Amaryllidaceae/química , Antineoplásicos Fitogênicos/isolamento & purificação , Antineoplásicos Fitogênicos/farmacologia , Apoptose/efeitos dos fármacos , Linhagem Celular Tumoral , Células Hep G2 , Compostos Heterocíclicos de 4 ou mais Anéis/isolamento & purificação , Humanos , Células MCF-7
4.
Arch Virol ; 166(10): 2817-2823, 2021 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-34279720

RESUMO

Nineteen samples from members of the plant genera Agapanthus, Clivia, Hippeastrum, and Scadoxus were collected from gardens in the Gauteng and Western Cape provinces of South Africa. The plants displayed highly variable symptoms of viral disease, including chlorosis, necrosis, streaking, and ringspot. RNAtag-seq was used to characterize the associated viral populations. Plants of the genus Agapanthus were found to be associated with three novel viruses from the families Caulimoviridae, Closteroviridae, and Betaflexiviridae; plants of the genus Clivia were associated with novel members of the families Potyviridae and Betaflexiviridae; and plants of the genus Scadoxus were associated with a novel member of the family Tospoviridae. Nerine latent virus was associated with plants of the genera Agapanthus, Clivia, and Hippeastrum, while hippeastrum mosaic virus was associated exclusively with a Hippeastrum cultivar.


Assuntos
Amaryllidaceae/virologia , Vírus de Plantas/isolamento & purificação , Amaryllidaceae/classificação , Sequência de Aminoácidos , Genoma Viral/genética , Especificidade de Hospedeiro , Doenças das Plantas/virologia , Vírus de Plantas/classificação , Vírus de Plantas/genética , África do Sul , Proteínas Virais/genética
5.
Antimicrob Agents Chemother ; 65(9): e0039821, 2021 08 17.
Artigo em Inglês | MEDLINE | ID: mdl-34152811

RESUMO

Dengue fever, caused by dengue virus (DENV), is the most prevalent arthropod-borne viral disease and is endemic in many tropical and subtropical parts of the world, with an increasing incidence in temperate regions. The closely related flavivirus Zika virus (ZIKV) can be transmitted vertically in utero and causes congenital Zika syndrome and other birth defects. In adults, ZIKV is associated with Guillain-Barré syndrome. There are no approved antiviral therapies against either virus. Effective antiviral compounds are urgently needed. Amaryllidaceae alkaloids (AAs) are a specific class of nitrogen-containing compounds produced by plants of the Amaryllidaceae family with numerous biological activities. Recently, the AA lycorine was shown to present strong antiflaviviral properties. Previously, we demonstrated that Crinum jagus contained lycorine and several alkaloids of the cherylline, crinine, and galanthamine types with unknown antiviral potential. In this study, we explored their biological activities. We show that C. jagus crude alkaloid extract inhibited DENV infection. Among the purified AAs, cherylline efficiently inhibited both DENV (50% effective concentration [EC50], 8.8 µM) and ZIKV replication (EC50, 20.3 µM) but had no effect on HIV-1 infection. Time-of-drug-addition and -removal experiments identified a postentry step as the one targeted by cherylline. Consistently, using subgenomic replicons and replication-defective genomes, we demonstrate that cherylline specifically hinders the viral RNA synthesis step but not viral translation. In conclusion, AAs are an underestimated source of antiflavivirus compounds, including the effective inhibitor cherylline, which could be optimized for new therapeutic approaches.


Assuntos
Alcaloides , Alcaloides de Amaryllidaceae , Amaryllidaceae , Vírus da Dengue , Dengue , Infecção por Zika virus , Zika virus , Adulto , Alcaloides/farmacologia , Alcaloides de Amaryllidaceae/farmacologia , Humanos , Isoquinolinas , Replicação Viral , Infecção por Zika virus/tratamento farmacológico
6.
Parasit Vectors ; 14(1): 337, 2021 Jun 26.
Artigo em Inglês | MEDLINE | ID: mdl-34174959

RESUMO

BACKGROUND: Chagas disease is a neglected zoonosis caused by the parasite Trypanosoma cruzi. It affects over six million people, mostly in Latin America. Drugs available to treat T. cruzi infection have associated toxicity and questionable efficacy at the chronic stage. Hence, the discovery of more effective and safer drugs is an unmet medical need. For this, natural products represent a pool of unique chemical diversity that can serve as excellent templates for the synthesis of active molecules. METHODS: A collection of 79 extracts of Amaryllidaceae plants were screened against T. cruzi. Active extracts against the parasite were progressed through two cell toxicity assays based on Vero and HepG2 cells to determine their selectivity profile and discard those toxic to host cells. Anti-T. cruzi-specific extracts were further qualified by an anti-amastigote stage assay. RESULTS: Two extracts, respectively from Crinum erubescens and Rhodophiala andicola, were identified as highly active and specific against T. cruzi and its mammalian replicative form. CONCLUSIONS: The results retrieved in this study encourage further exploration of the chemical content of these extracts in search of new anti-T. cruzi drug development starting points.


Assuntos
Amaryllidaceae/química , Doença de Chagas/parasitologia , Extratos Vegetais/farmacologia , Tripanossomicidas/farmacologia , Doença de Chagas/tratamento farmacológico , Avaliação Pré-Clínica de Medicamentos , Humanos , Tripanossomicidas/química , Trypanosoma cruzi/efeitos dos fármacos , Trypanosoma cruzi/fisiologia
7.
Plant Sci ; 308: 110928, 2021 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-34034876

RESUMO

Cell death is an inevitably cryo-injury in cell and tissue cryopreservation. The research on programmed cell death (PCD) in plant cryopreservation is still in its infancy. In this study, the survival rate of Agapanthus praecox embryogenic callus was significantly improved when the vitrification solution was added with 20 µM E-64, which is an inhibitor of cathepsin B. For further investigating the relation between cathepsin B and cryo-injury, the coding gene of cathepsin B, ApCathB was isolated and characterized. A subcellular localization assay showed that ApCathB was located in cytomembrane. Heterologous overexpression of ApCathB reduced the recovery rate during Arabidopsis seedlings cryopreservation from 29.56 % to 16.46 %. Transgenic seedlings lost most of cell viability in hypocotyl after dehydration and lead to aggravated cryo-injury. The reduced survival rate of ApCathB-overexpressing embryogenic callus of A. praecox further confirmed its negatively function in cryo-injury tolerance. In addition, the survival of ApCathB-overexpressing lines was almost rescued by E-64. TUNEL detection showed intensified signal and ROS was burst, especially for H2O2. Furthermore, VPE, Metacaspase 1, Cyp15a and AIF genes related to cell death regulation were remarkably up-regulated in ApCathB-overexpressing embryogenic callus during cryopreservation. Additionally, the expression level of genes regulating cell degradation was also elevated, indicating accelerated cell death caused by ApCathB-overexpressing. Taken together, this work verified that ApCathB negatively regulated the cryo-injury tolerance and cell viability through mediating the PCD event in plant cryopreservation. Significantly, cathepsin B has potential to be a target to improve survival rate after cryopreservation.


Assuntos
Amaryllidaceae/fisiologia , Arabidopsis/fisiologia , Catepsina B/genética , Resposta ao Choque Frio , Proteínas de Plantas/genética , Amaryllidaceae/genética , Sequência de Aminoácidos , Arabidopsis/genética , Catepsina B/química , Catepsina B/metabolismo , Resposta ao Choque Frio/genética , Congelamento , Filogenia , Proteínas de Plantas/química , Proteínas de Plantas/metabolismo , Plantas Geneticamente Modificadas/genética , Plantas Geneticamente Modificadas/fisiologia , Alinhamento de Sequência
8.
J Pharm Biomed Anal ; 199: 114061, 2021 May 30.
Artigo em Inglês | MEDLINE | ID: mdl-33845386

RESUMO

Hippeastrum elegans is an Amaryllidaceae species producing alkaloids with pharmaceutical potential including lycorine and galanthamine. Herein, we developed a non-targeted metabolomic study associated to chemometrics and biological evaluations to identify the H. elegans constituents that were able to reduce the human neutrophils proinflammatory mechanisms. The alkaloid fractions were extracted from bulbs cultivated for 15 months (m) and harvested in six harvest periods (5, 7, 9, 11, 13, and 15 m). The GC-MS analysis allowed the detection of 41 alkaloids being 31 identified. All alkaloid components varied over the cultivation and most of them were lycorine-type skeletons. Principal Component Analysis (PCA) and Hierarchical Cluster Analysis (HCA) distinguished three groups according to the chemical profile (group I: 5, 7, and 9 m; group II: 11 m and group III: 13 and 15 m). Therefore, the biological assays were only performed with one of the representative samples of each group: 7 m, 11 m and 15 m. None of them was toxic to human neutrophils by LDH activity and MTT test. The 7 m and 15 m-alkaloid fractions showed anti-inflammatory effects by reducing human neutrophil degranulation. However, the former one was more effective in inhibiting the cell activation based on the reduction of myeloperoxidase (MPO) release and reactive oxygen species (ROS) production. Afterwards, Partial Least Squares analysis (PLS) indicated lycorine and 11,12-dehydro-2-methoxy-assoanine as the compounds responsible for the anti-inflammatory activity of the bioactive fraction. Thus, the 7 m-alkaloid fraction of H. elegans seems to be a promising anti-inflammatory drug that deserves additional research.


Assuntos
Alcaloides , Alcaloides de Amaryllidaceae , Amaryllidaceae , Alcaloides de Amaryllidaceae/farmacologia , Anti-Inflamatórios/farmacologia , Cromatografia Gasosa-Espectrometria de Massas , Humanos , Neutrófilos , Extratos Vegetais
9.
Planta Med ; 87(12-13): 916-936, 2021 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-33706400

RESUMO

Over 600 alkaloids have to date been identified in the plant family Amaryllidaceae. These have been arranged into as many as 15 different groups based on their characteristic structural features. The vast majority of studies on the biological properties of Amaryllidaceae alkaloids have probed their anticancer potential. While most efforts have focused on the major alkaloid groups, the volume and diversity afforded by the minor alkaloid groups have promoted their usefulness as targets for cancer cell line screening purposes. This survey is an in-depth review of such activities described for around 90 representatives from 10 minor alkaloid groups of the Amaryllidaceae. These have been evaluated against over 60 cell lines categorized into 18 different types of cancer. The montanine and cripowellin groups were identified as the most potent, with some in the latter demonstrating low nanomolar level antiproliferative activities. Despite their challenging molecular architectures, the minor alkaloid groups have allowed for facile adjustments to be made to their structures, thereby altering the size, geometry, and electronics of the targets available for structure-activity relationship studies. Nevertheless, it was seen with a regular frequency that the parent alkaloids were better cytotoxic agents than the corresponding semisynthetic derivatives. There has also been significant interest in how the minor alkaloid groups manifest their effects in cancer cells. Among the various targets and pathways in which they were seen to mediate, their ability to induce apoptosis in cancer cells is most appealing.


Assuntos
Alcaloides , Alcaloides de Amaryllidaceae , Amaryllidaceae , Alcaloides/farmacologia , Alcaloides de Amaryllidaceae/farmacologia , Apoptose , Citotoxinas
10.
Chem Biodivers ; 18(3): e2000834, 2021 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-33594810

RESUMO

The Libellus de Medicinalibus Indorum Herbis (Booklet of Indian Medicinal Plants) is the first book of medicinal plants written in the American continent. It was first published in 1939 as 'An Aztec Herbal'. One of the depicted plants is Huetzcanixochitl (laughing flower) interpreted as Zephyranthes fosteri (Amaryllidaceae). No chemical or pharmacological studies are reported for this species; so, we decide to investigate it. The GC/MS of the bulbs and aerial parts extracts indicated that they contain Amaryllidaceae alkaloids, among them: lycorine, 3-O-acetylpowelline, and norlycoramine. An unknown major alkaloid was isolated and identified by 1 H, 13 C-NMR and MS, as 3'-demethoxy-6-epimesembranol (1). The methanolic extract, the alkaloid fraction, and compound 1 inhibited acetylcholinesterase in vitro. Mesembrine alkaloids are found in Sceletium species (Aizoaceae). Several are known as serotonin recapture inhibitors and have been proposed as potential antidepressant drugs. The presence of 1 suggests that Z. fosteri was probably used in pre-Columbian times in Mexico as a 'stimulant and euphoriant', alike Sceletium tortuosum by several ethnic groups in South Africa.


Assuntos
Alcaloides/farmacologia , Amaryllidaceae/química , Inibidores da Colinesterase/farmacologia , Compostos Fitoquímicos/farmacologia , Plantas Medicinais/química , Acetilcolinesterase/metabolismo , Alcaloides/química , Alcaloides/isolamento & purificação , Animais , Inibidores da Colinesterase/química , Inibidores da Colinesterase/isolamento & purificação , Relação Dose-Resposta a Droga , Electrophorus , México , Estrutura Molecular , Compostos Fitoquímicos/química , Compostos Fitoquímicos/isolamento & purificação , Estereoisomerismo , Relação Estrutura-Atividade
11.
Molecules ; 26(3)2021 Jan 26.
Artigo em Inglês | MEDLINE | ID: mdl-33530604

RESUMO

The role and importance of the identification of natural products are discussed in the perspective of the study of secondary metabolites. The rapid identification of already reported compounds, or structural dereplication, is recognized as a key element in natural product chemistry. The biological taxonomy of metabolite producing organisms, the knowledge of metabolite molecular structures, and the availability of metabolite spectroscopic signatures are considered as the three pillars of structural dereplication. The role and the construction of databases is illustrated by references to the KNApSAcK, UNPD, CSEARCH, and COCONUT databases, and by the importance of calculated taxonomic and spectroscopic data as substitutes for missing or lost original ones. Two NMR-based tools, the PNMRNP database that derives from UNPD, and KnapsackSearch, a database generator that provides taxonomically focused libraries of compounds, are proposed to the community of natural product chemists. The study of the alkaloids from Urceolina peruviana, a plant from the Andes used in traditional medicine for antibacterial and anticancer actions, has given the opportunity to test different approaches to dereplication, favoring the use of publicly available data sources.


Assuntos
Alcaloides/química , Amaryllidaceae/química , Produtos Biológicos/química , Química Computacional , Bases de Dados de Produtos Farmacêuticos , Estrutura Molecular , Raízes de Plantas/química , Metabolismo Secundário
12.
Int J Mol Sci ; 22(4)2021 Feb 10.
Artigo em Inglês | MEDLINE | ID: mdl-33578992

RESUMO

In this study, endophytic bacteria belonging to the Bacillus genus were isolated from in vitro bulblets of Leucojum aestivum and their ability to produce Amaryllidaceae alkaloids was studied. Proton Nuclear Magnetic Resonance (1H NMR)-based metabolomics combined with multivariate data analysis was chosen to compare the metabolism of this plant (in vivo bulbs, in vitro bulblets) with those of the endophytic bacteria community. Primary metabolites were quantified by quantitative 1H NMR (qNMR) method. The results showed that tyrosine, one precursor of the Amaryllidaceae alkaloid biosynthesis pathway, was higher in endophytic extract compared to plant extract. In total, 22 compounds were identified including five molecules common to plant and endophyte extracts (tyrosine, isoleucine, valine, fatty acids and tyramine). In addition, endophytic extracts were analyzed using Liquid Chromatography-Mass Spectrometry (LC-MS) and Gas Chromatography-Mass Spectrometry (GC-MS) for the identification of compounds in very low concentrations. Five Amaryllidaceae alkaloids were detected in the extracts of endophytic bacteria. Lycorine, previously detected by 1H NMR, was confirmed with LC-MS analysis. Tazettine, pseudolycorine, acetylpseudolycorine, 1,2-dihydro-chlidanthine were also identified by LC-MS using the positive ionization mode or by GC-MS. In addition, 11 primary metabolites were identified in the endophytic extracts such as tyramine, which was obtained by decarboxylation of tyrosine. Thus, Bacillus sp. isolated from L. aestivum bulblets synthesized some primary and specialized metabolites in common with the L.aestivum plant. These endophytic bacteria are an interesting new approach for producing the Amaryllidaceae alkaloid such as lycorine.


Assuntos
Alcaloides de Amaryllidaceae/metabolismo , Amaryllidaceae/microbiologia , Bacillus/metabolismo , Endófitos/metabolismo , Alcaloides de Amaryllidaceae/análise , Bacillus/química , Bacillus/isolamento & purificação , Cromatografia Líquida , Endófitos/química , Endófitos/isolamento & purificação , Microbiologia Industrial/métodos , Espectroscopia de Ressonância Magnética , Espectrometria de Massas , Metabolômica
13.
Sci Rep ; 11(1): 3262, 2021 02 05.
Artigo em Inglês | MEDLINE | ID: mdl-33547390

RESUMO

Allioideae includes economically important bulb crops such as garlic, onion, leeks, and some ornamental plants in Amaryllidaceae. Here, we reported the complete chloroplast genome (cpDNA) sequences of 17 species of Allioideae, five of Amaryllidoideae, and one of Agapanthoideae. These cpDNA sequences represent 80 protein-coding, 30 tRNA, and four rRNA genes, and range from 151,808 to 159,998 bp in length. Loss and pseudogenization of multiple genes (i.e., rps2, infA, and rpl22) appear to have occurred multiple times during the evolution of Alloideae. Additionally, eight mutation hotspots, including rps15-ycf1, rps16-trnQ-UUG, petG-trnW-CCA, psbA upstream, rpl32-trnL-UAG, ycf1, rpl22, matK, and ndhF, were identified in the studied Allium species. Additionally, we present the first phylogenomic analysis among the four tribes of Allioideae based on 74 cpDNA coding regions of 21 species of Allioideae, five species of Amaryllidoideae, one species of Agapanthoideae, and five species representing selected members of Asparagales. Our molecular phylogenomic results strongly support the monophyly of Allioideae, which is sister to Amaryllioideae. Within Allioideae, Tulbaghieae was sister to Gilliesieae-Leucocoryneae whereas Allieae was sister to the clade of Tulbaghieae- Gilliesieae-Leucocoryneae. Molecular dating analyses revealed the crown age of Allioideae in the Eocene (40.1 mya) followed by differentiation of Allieae in the early Miocene (21.3 mya). The split of Gilliesieae from Leucocoryneae was estimated at 16.5 mya. Biogeographic reconstruction suggests an African origin for Allioideae and subsequent spread to Eurasia during the middle Eocene. Cool and arid conditions during the late Eocene led to isolation between African and Eurasian species. African Allioideae may have diverged to South American taxa in the late Oligocene. Rather than vicariance, long-distance dispersal is the most likely explanation for intercontinental distribution of African and South American Allioideae species.


Assuntos
Amaryllidaceae/genética , Genoma de Cloroplastos , DNA de Plantas/genética , Evolução Molecular , Filogenia , RNA de Plantas/genética
14.
PLoS One ; 16(1): e0244737, 2021.
Artigo em Inglês | MEDLINE | ID: mdl-33395438

RESUMO

The presented study evaluated effects of potassium nitrate (KNO3), ammonium nitrate (NH4 NO3) and ammonium chloride (NH4Cl) on the germination-related characteristics of 10 species from European dry acidic grasslands. Germination was studied under controlled laboratory conditions. The seeds were subjected to KNO3, NH4 NO3 and NH4Cl in four doses (1, 10, 50 and 100 mM) and to distilled water. Final germination percentage, index of germination velocity and index of germination synchrony were determined. Content of nitrogen in the soil probed from the site of seeds collection was also analyzed. Significant effects of type of the nitrogen compounds and their concentrations were observed. High concentrations of nitrogen-containing salts inhibited completion of germination in almost all species. Helichrysum arenarium and Hypericum perforatum showed preference for NH4+ over NO3‒, whereas Arnoseris minima, Alyssum montanum, Jasione montana and Spergula morisonii showed preference for NO3‒ over NH4+. Centaurea scabiosa, C. stoebe and Hypochaeris radicata had no preference and wide tolerance to the type of nitrogen-containing compound. Echium vulgare showed differential response hard for interpretation. A. montanum and J. montana showed stenotopic behavior in terms of nitrogen-related conditions. It is proposed that nitrogen-rich soil gaps favor establishment of more nitro-tolerant plant species (e.g. C. scabiosa, C. stoebe and H. radicata) as compared to nitrogen-poor ones.


Assuntos
Ácidos/química , Amaryllidaceae/crescimento & desenvolvimento , Ecologia , Germinação , Pradaria , Nitrogênio/metabolismo , Sementes/crescimento & desenvolvimento , Amaryllidaceae/metabolismo , Europa (Continente) , Sementes/metabolismo
15.
Molecules ; 26(1)2021 Jan 02.
Artigo em Inglês | MEDLINE | ID: mdl-33401696

RESUMO

Plants in the Amaryllidaceae family synthesize a diversity of bioactive alkaloids. Some of these plant species are not abundant and have a low natural multiplication rate. The aims of this work were the alkaloids analysis of a Habranthus cardenasianus bulbs extract, the evaluation of its inhibitory activity against cholinesterases, and to test several propagation strategies for biomass production. Eleven compounds were characterized by GC-MS in the alkaloid extract, which showed a relatively high proportion of tazettine. The known alkaloids tazettine, haemanthamine, and the epimer mixture haemanthidine/6-epi-haemanthidine were isolated and identified by spectroscopic methods. Inhibitory cholinesterases activity was not detected. Three forms of propagation were performed: bulb propagation from seed, cut-induced bulb division, and micropropagated bulbs. Finally, different imbibition and post-collection times were evaluated in seed germination assays. The best propagation method was cut-induced bulb division with longitudinal cuts into quarters (T1) while the best conditions for seed germination were 0-day of post-collection and two days of imbibition. The alkaloids analyses of the H. cardenasianus bulbs showed that they are a source of anti-tumoral alkaloids, especially pretazettine (tazettine) and T1 is a sustainable strategy for its propagation and domestication to produce bioactive alkaloids.


Assuntos
Alcaloides/análise , Alcaloides/farmacologia , Amaryllidaceae/química , Amaryllidaceae/crescimento & desenvolvimento , Inibidores da Colinesterase/farmacologia , Alcaloides/química , Alcaloides/isolamento & purificação , Alcaloides de Amaryllidaceae/análise , Biomassa , Butirilcolinesterase/metabolismo , Inibidores da Colinesterase/química , Cromatografia Gasosa-Espectrometria de Massas , Germinação , Estrutura Molecular , Fenantridinas/análise , Extratos Vegetais/química , Extratos Vegetais/farmacologia , Raízes de Plantas/crescimento & desenvolvimento , Sementes/crescimento & desenvolvimento , Fatores de Tempo
16.
Bioorg Chem ; 107: 104567, 2021 02.
Artigo em Inglês | MEDLINE | ID: mdl-33387730

RESUMO

Twenty known Amaryllidaceae alkaloids of various structural types, and one undescribed alkaloid of narcikachnine-type, named narcieliine (3), have been isolated from fresh bulbs of Zephyranthes citrina. The chemical structures of the isolated alkaloids were elucidated by a combination of MS, HRMS, 1D and 2D NMR, and CD spectroscopic techniques, and by comparison with literature data. The absolute configuration of narcieliine (3) has also been determined. Compounds isolated in a sufficient quantity 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 AChE/BuChE (hAChE/hBuChE) inhibitory activity was demonstrated by the newly described alkaloid narcieliine (3), with IC50 values of 18.7 ± 2.3 µM and 1.34 ± 0.31 µM, respectively. This compound is also predicted to cross the blood-brain barrier (BBB) through passive diffusion. The in vitro data were further supported by in silico studies of 3 in the active site of hAChE/hBuChE.


Assuntos
Alcaloides/química , Amaryllidaceae/química , Acetilcolinesterase/química , Acetilcolinesterase/metabolismo , Alcaloides/isolamento & purificação , Alcaloides/farmacologia , Alcaloides/uso terapêutico , Doença de Alzheimer/tratamento farmacológico , Doença de Alzheimer/patologia , Amaryllidaceae/metabolismo , Sítios de Ligação , Barreira Hematoencefálica/efeitos dos fármacos , Barreira Hematoencefálica/metabolismo , Butirilcolinesterase/química , Butirilcolinesterase/metabolismo , Domínio Catalítico , Inibidores da Colinesterase/química , Inibidores da Colinesterase/metabolismo , Inibidores da Colinesterase/farmacologia , Inibidores da Colinesterase/uso terapêutico , Humanos , Cinética , Espectroscopia de Ressonância Magnética , Conformação Molecular , Simulação de Acoplamento Molecular , Relação Estrutura-Atividade
17.
Gene ; 774: 145424, 2021 Mar 30.
Artigo em Inglês | MEDLINE | ID: mdl-33434626

RESUMO

The Narcissus pseudonarcissus cv. Carlton contains Amaryllidaceae alkaloids namely galanthamine, lycorine, homolycorine, narciclasine, which are noted for their pharmaceutical properties such as for the treatment of early to mid-stage Alzheimer's diseases, cancer, tumor etc. Alkaloid biosynthesis using plant in vitro systems has been considered as a tool for drug discovery and the pathways are starting to be understood but still far from complete. Therefore, the study was emphasized to observe the relative expressions of putative genes involved in the biosynthetic pathway leading to the Amaryllidaceae alkaloids in field grown bulbs and developing cell culture systems in Narcissus. MS media fortified with growth regulators were used for the development of tissue culture from Carlton twin-scale explants. MS medium with high auxin, 20 mg/l NAA was the best medium for callus growth and maintenance while media with low auxin, 4 mg/l NAA and MS basal media gave the maximum bulblets. Field tissues showed a higher amount of galanthamine content; i.e. basal plate (1050-1310 µg Gal/g FW) and bulb (980-1150 µg Gal/g FW) than the culture derived samples; callus (1.0-7.0 µg Gal/g FW) and bulblets (12-215 µg Gal/g FW) on a fresh weight (FW) basis. GC-MS chromatograms of samples under study also showed the presence of other important alkaloids i.e. lycorine, homolycorine, lycorenine, haemanthamine, crinamine, lycoramine and tazettine. RNA extracted from in vitro callus, bulblets and field grown bulb, basal plate were used for PCR to detect the relative expression of putative genes; P450, PAL, TYDC and NpO4OMT normalized to actin. The selected transcripts for P450s and TYDC were expressed in both field and in vitro tissues. Higher expressions of PAL were observed in calli than field samples. The expression of NpN4OMT was notably higher in field samples than in vitro tissues. Therefore, in vitro tissues could be a good source for the reproducible and easy extraction of alkaloids from plants.


Assuntos
Alcaloides de Amaryllidaceae/metabolismo , Amaryllidaceae/genética , Galantamina/genética , Genes de Plantas , Narcissus/genética , Amaryllidaceae/efeitos dos fármacos , Amaryllidaceae/metabolismo , Meios de Cultura , Galantamina/biossíntese , Perfilação da Expressão Gênica , Narcissus/efeitos dos fármacos , Narcissus/metabolismo , Reguladores de Crescimento de Plantas/farmacologia , Técnicas de Cultura de Tecidos
18.
Mol Biol Rep ; 48(1): 513-526, 2021 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-33442831

RESUMO

Genus Zephyranthes consists of economically important plant species due to their high ornamental value and presence of valuable bioactive compounds. However, this genus propagates by asexual division only which gives slow propagation rate. Plant tissue culture has the potential to provide efficient techniques for rapid multiplication and genetic improvement of the genus. In this work, a dual in vitro regeneration system through callus mediated shoot regeneration and direct shoot regeneration in species Zephyranthes candida, Zephyranthes grandiflora and Zephyranthes citrina was investigated. Bulb, leaf and root explants were cultured on Murashige and Skoog (MS) medium amended with different plant growth regulators (PGR's) viz. 2,4-dichlorophenoxyacetic acid (2,4-D), 1-Naphthalene acetic acid (NAA), 6-benzyl amino purine (BAP), N-phenyl-N'-1,2,3 -thiadiazol-5-ylurea (TDZ), 6-Furfuryl- aminopurine (KIN) alone or in combinations for callus induction and regeneration. Only bulb explants showed callus induction and regeneration response on different PGR combinations with a varied response in callus induction percentage, callus color and callus texture. Creamish compact callus (CC) was induced on 2 mg L[Formula: see text] 2,4-D, brown friable callus (BF) on 2 mg L[Formula: see text] NAA + 1 mg L[Formula: see text] BAP and green friable callus (GF) callus on 1 mg L[Formula: see text] KIN + 3 mg L[Formula: see text] NAA. The maximum shoot multiplication from different callus types (indirect organogenesis) was achieved on 2 mg L[Formula: see text] BAP alone without combinations. Bulb explants of Z. grandiflora induced maximum callus induction percentage (86.4%) and shoot regeneration percentage (83.5%) with the maximum 08 shoots per 150 mg callus mass. The induction and regeneration response was followed in the order of Z. grandiflora > Z. candida > Z. citrina. Similarly, maximum direct organogenesis from bulb explants was obtained in Z. grandiflora (93.3%) followed by Z. candida (91.5%) and Z. citrina (90.4%) on 3 mg L[Formula: see text] TDZ amended MS media. Adventitious root induction was achieved on 2 mg L[Formula: see text] IBA with a maximum of 8 roots per shoot. The in vitro raised plantlets were successfully acclimatized in the field with 85% survival efficiency. The genome size (2C DNA content) of the field-grown plants and in vitro regenerated plants, evaluated through flow cytometry technique, were similar and showed no ploidy changes. An efficient mass propagation protocol was established for obtaining plants with unaltered genome size in the three species of Zephyranthes.


Assuntos
Amaryllidaceae/genética , Organogênese/genética , Desenvolvimento Vegetal/genética , Regeneração/genética , Amaryllidaceae/crescimento & desenvolvimento , Calo Ósseo/crescimento & desenvolvimento , Citometria de Fluxo , Tamanho do Genoma/genética , Genoma de Planta/genética , Reguladores de Crescimento de Plantas/genética , Folhas de Planta/genética , Folhas de Planta/crescimento & desenvolvimento , Raízes de Plantas/genética , Raízes de Plantas/crescimento & desenvolvimento , Brotos de Planta/genética , Brotos de Planta/crescimento & desenvolvimento , Ploidias
19.
Nat Prod Res ; 35(5): 807-814, 2021 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-30990078

RESUMO

Acetylcholinesterase (AChE) inhibitors remain the class of drugs used for the treatment of Alzheimer disease (AD). For the aim of discovering new sources of potent AChE inhibitors, a combined AChE-inhibitory activity together with alkaloid profiles by GC-MS, combined with multivariate statistical analysis for biomarkers determination and in silico studies were attempted. Strategy was applied on leaves, roots and bulbs of six aquatic and terrestrial Amaryllidaceae species. Thirty alkaloids were identified and the AChE inhibitory activities of the extracts were tested by in-vitro Ellman method. Principal bioactive markers were discovered by correlating AChE inhibitory activity with chemical fingerprints via PLS and OPLS modeling which revealed that galanthamine, lycoramine, caranine, tazettine and N-demethylgalanthamine were the most bio-significant markers. Furthermore, the molecular docking was performed to illustrate binding orientations of the top scoring alkaloids in the active site of human acetylcholinesterase. Suggested strategy revealed that, beside galanthamine, caranine, N-demethylgalanthamine, and lycoramine are promising AChE inhibitors.


Assuntos
Alcaloides/farmacologia , Amaryllidaceae/química , Inibidores da Colinesterase/farmacologia , Simulação por Computador , Crinum/química , Cromatografia Gasosa-Espectrometria de Massas , Acetilcolinesterase/metabolismo , Alcaloides/química , Doença de Alzheimer , Alcaloides de Amaryllidaceae/química , Alcaloides de Amaryllidaceae/farmacologia , Domínio Catalítico , Inibidores da Colinesterase/química , Galantamina/química , Galantamina/farmacologia , Humanos , Simulação de Acoplamento Molecular , Análise Multivariada , Extratos Vegetais/química , Folhas de Planta/química , Raízes de Plantas/química
20.
Artigo em Inglês | MEDLINE | ID: mdl-33288640

RESUMO

Here, we report on the anti-influenza virus activity of the mannose-binding agents Hippeastrum hybrid agglutinin (HHA) and Galanthus nivalis agglutinin (GNA) and the (N-acetylglucosamine) n -specific Urtica dioica agglutinin (UDA). These carbohydrate-binding agents (CBA) strongly inhibited various influenza A(H1N1), A(H3N2), and B viruses in vitro, with 50% effective concentration values ranging from 0.016 to 83 nM, generating selectivity indexes up to 125,000. Somewhat less activity was observed against A/Puerto Rico/8/34 and an A(H1N1)pdm09 strain. In time-of-addition experiments, these CBA lost their inhibitory activity when added 30 min postinfection (p.i.). Interference with virus entry processes was also evident from strong inhibition of virus-induced hemolysis at low pH. However, a direct effect on acid-induced refolding of the viral hemagglutinin (HA) was excluded by the tryptic digestion assay. Instead, HHA treatment of HA-expressing cells led to a significant reduction of plasma membrane mobility. Crosslinking of membrane glycoproteins, through interaction with HA, could also explain the inhibitory effect on the release of newly formed virions when HHA was added at 6 h p.i. These CBA presumably interact with one or more N-glycans on the globular head of HA, since their absence led to reduced activity against mutant influenza B viruses and HHA-resistant A(H1N1) viruses. The latter condition emerged only after 33 cell culture passages in the continuous presence of HHA, and the A(H3N2) virus retained full sensitivity even after 50 passages. Thus, these CBA qualify as potent inhibitors of influenza A and B viruses in vitro with a pleiotropic mechanism of action and a high barrier for viral resistance.


Assuntos
Amaryllidaceae , Herpesvirus Cercopitecino 1 , Vírus da Influenza A Subtipo H1N1 , Influenza Humana , Aglutininas , Antivirais/farmacologia , Glicoproteínas de Hemaglutininação de Vírus da Influenza , Humanos , Vírus da Influenza A Subtipo H3N2 , Vírus da Influenza B , Manose , Lectinas de Ligação a Manose , Lectinas de Plantas , Replicação Viral
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